Quaternary Journal of Iran

Abstract Introduction Urban green spaces, particularly public parks, play a vital role in enhancing environmental quality and improving public health in rapidly expanding cities. However, these areas are increasingly exposed to contamination from anthropogenic sources, with heavy metal pollution being one of the most concerning threats. Urban soils, especially in parks, can accumulate potentially toxic elements (PTEs) due to vehicular emissions, industrial activities, atmospheric deposition, and inappropriate use of fertilizers and pesticides. Monitoring heavy metal concentrations in park soils is therefore essential to evaluate potential environmental risks and inform urban environmental management strategies. This study focuses on the spatial assessment of heavy metal contamination in soils of selected urban parks using pollution indices and Geographic Information Systems (GIS). Heavy metals such as lead (Pb), cadmium (Cd), arsenic (As), chromium (Cr), copper (Cu), zinc (Zn), and nickel (Ni) are selected based on their toxicity, persistence in the environment, and potential health impacts on urban populations. Sampling and Analytical Methods Soil samples were systematically collected from different locations within each urban park to capture spatial variability. The topsoil layer (0–20 cm) was targeted, as it is most susceptible to anthropogenic contamination. Samples were air-dried, sieved, and subjected to acid digestion based on USEPA standard protocols. Heavy metal concentrations were then measured using atomic absorption spectrometry (AAS) or inductively coupled plasma mass spectrometry (ICP-MS), depending on the element and required detection limits. Application of Pollution Indices To assess contamination levels, multiple pollution indices were employed: 1. Geoaccumulation Index (Igeo) – developed by Müller, this index compares current concentrations with background values to determine pollution levels. Values are classified into seven categories, ranging from unpolluted to extremely polluted. 2. Contamination Factor (CF) – this index is the ratio of metal concentration in soil to the background concentration, indicating the degree of contamination. 3. Enrichment Factor (EF) – used to differentiate between anthropogenic and natural sources, calculated using a reference element such as Fe or Al. 4. Pollution Load Index (PLI) – provides a cumulative indication of overall pollution status across multiple metals. 5. Ecological Risk Index (RI) – developed by Hakanson, this index combines toxic response factors with contamination levels to quantify ecological risk posed by each heavy metal. These indices offer a comprehensive view of the contamination status and help prioritize elements of greatest concern. GIS-Based Spatial Analysis GIS tools were applied to interpolate the spatial distribution of heavy metals across the park areas using kriging or inverse distance weighting (IDW) methods. This spatial analysis helps identify pollution hotspots and understand the influence of surrounding urban land use on soil contamination. In addition, land use maps, traffic density data, and proximity to pollution sources (e.g., highways, industrial zones) were integrated to explore potential sources of contamination. Layered visualization through GIS enhances interpretation and supports urban planning decisions. Results and Interpretation The results revealed considerable variations in heavy metal concentrations across different parks, with some areas exceeding international soil quality guidelines, particularly for Pb, Cd, and As. The Igeo values indicated moderate to high pollution levels in parks adjacent to high-traffic roads and industrial areas. CF and EF values confirmed anthropogenic contributions, with significant enrichment for Cu, Zn, and Pb. The ecological risk assessment highlighted Cd as the primary element posing considerable risk, followed by As and Pb. Some park locations fell into the "considerable risk" category according to the RI values, underscoring the need for targeted mitigation measures. Spatial distribution maps generated by GIS clearly identified pollution hotspots and indicated a correlation between metal accumulation and nearby anthropogenic activities. Parks located in city centers or near transportation corridors showed higher contamination levels, emphasizing the importance of buffer zones and soil remediation interventions. Environmental and Public Health Implications Heavy metal accumulation in urban park soils not only degrades soil quality and ecological health but also poses direct and indirect risks to human health. Children are particularly vulnerable due to frequent contact with park soils through play. Chronic exposure to heavy metals can lead to neurological disorders, kidney damage, and developmental delays.   Therefore, understanding spatial patterns and ecological risks associated with heavy metal contamination in urban parks is critical for environmental risk management. The application of pollution indices and GIS supports evidence-based decision-making and enhances public awareness. Recommendations 1. Regular Monitoring: Establish long-term monitoring programs in urban parks, especially in high-risk zones. 2. Remediation Strategies: Use phytoremediation or soil amendments to reduce bioavailability of heavy metals. 3. Urban Planning: Design green spaces with buffer zones and low-exposure zones for children. 4. Public Education: Raise awareness about contamination risks and promote safe park usage practices. 5. Policy Development: Implement regulations to limit urban emissions and manage land use near green spaces. Conclusion This study underscores the significance of combining pollution indices and GIS tools to assess heavy metal contamination in urban park soils. The findings reveal spatially heterogeneous contamination patterns and identify ecological and health risks, particularly in parks located in densely populated or industrialized zones. An integrated approach to monitoring, remediation, and urban design is essential for safeguarding environmental quality and ensuring the safe use of urban green spaces.

Abstract 1- Introduction

Lake basins have spatially and temporally index patterns and represent valuable maps of physical and chemical history. According to this point, that direct survey of climate changes has only been available as machinery in the past few decades, so paleo climatic changes indexes can give a better understanding of climate changes in the past era and its causes. Lake sediments have an extraordinary potantial to record climatic and environmental events with high sensitivity and resolution amounts. Therefore, lake sediments can be considered as regions for detecting paleo environments. Chegarman Lake formed in the northeast of Khuzestan province on the hillsides of folded Zagros and under the Izeh unit in a pit. This study has been tried to by Sedimentary geochemistry analyze, Elemental ratios, identification of sedimentary facies, and identification of sedimentary environments and changes of these environments set to the reformation the climatic and environmental conditions of Chegarman wetland in the Late Holocene.



2- Methods and Findings

The steps of this research include book studies, field works, laboratory works, statistical data processing and then interpretation and conclusion. To investigate the paleoclimate and conditions of the sedimentary environment, one intact sediment cores with a maximum depth of 7.2 m collected with using Auger corer. 21sediment samples were selected for elemental analysis with ICP-OES and XRF (X-Ray fluorescence). Statistical parameters, histogram diagrams of element frequency and cluster analysis were performed to determine the relationships between the elements in SPSS software. In this study, elemental ratios of V/Cr, Mn/Al, K/Al, Rb/Al, Si/Fe, Ti/K were used to reconstruction of the paleo climatic and environmental conditions. Which led to the study of the amount of detrital material, the severity of weathering and erosion in the catchment and fluctuations in the water level of the lake.



3- Results and discussion

In the studied core, 5 major sedimentary facies identified. Facies often contains clay, silt, gravel, and interstitial sediments along with vegetation and shell fossils which in most cases frequency and interference in the mentioned sediments are often seen. Changes were in particle size between clay to gravel due to process type changes, environment's energy and river input's amounts and sediment color variations concerning sedimentation conditions, presence of organic matter, pH amount, salinity and temperature variations, and drought occurrence, throughout the cores. Two wetland sedimentary and alluvial environments identified. According to the Chronology, the average sedimentation rate in the Chegarman wetland is 1.4 mm / year, which this amount is different for various depths (Darvishi et al., 2022). Due to the type of sediments, the high level water period of the Chegarman wetland has been established between 1250 and 150 years ago. The study of the facies sediments of the wetland bed shows that climate change occurred gradually (not suddenly) about 1250 years ago and this trend has taken at least 300 years. The relatively dry and cold period lasted about 1850 years from 3100 years to 1250 years ago and is confirmed with the reported dry periods in the Maharlou Lake about 1800 years ago, in the Mir Abad Lake about 1500 years ago and in the Urmia Lake between 2500 and 1500 years ago. From 4000 years ago to about 3100 years ago, stable and slow wetland conditions was prevailed. The conditions for creating a peatland environment have been provided in the wetland and were associated with increasing the amount of organic matter, vegetation and shell fossils and consequently increasing sedimentation rate. This period which lasted for about 900 years, has been accompanied by extremely humid conditions, high groundwater level and activity of springs in the region. The existence of light brown mud which has the age ranges from 4900 to 4000 years ago, indicates a dry period (900 years). This dry period shows suitable approximate conformity with a dry event of 4200 years ago in the northern hemisphere. This period in the studied region appeared with at least 100 years of temporal delay. After this dry period, we see again a gray sequence with plant and shell fossils that continue to a depth of 7 meters (about 5000 years ago). At depths of 7 to 7.2 m, the existence of brown-muddy sediments along with coarse-grained sediment in size of gravel, pebble and rubble, strengthen the possibility of very strong flood in the region that sent the coarse-grained sediments of around formation to bed of the wetland or maybe has hit to the area of wetland sediments bed in the region.



4. Conclusion

According to the results of surveys in the Chegarman wetland, at least 2 high water periods with humid climate and at least 2 dry periods during the Late Holocene were identified. Dry periods appear more suddenly and with more intensity and shorter duration than humid periods in the region and gradually lead to from very dry periods to semi-arid, semi-humid, and eventually humid periods.

Abstract Calcareous nannoplanktons are present in today's oceans significantly (Young & Bown, 1997, Thibault et al., 2012). As Coccolithophores, they are among the calcareous marine phytoplankton that live in oceanic waters and light seawater. Many have thought that the function of Coccolithus is light for photosynthesis for Coccolithophores (Gartner & Bukry, 1969). Coccolithophores, due to having chlorophyll, make the necessary food by themselves. Coccolithophores are involved in the preparation of biochemical limestones. Calcareous nannoplanktons emerged from the Norian and Rhaetian ages, during the Triassic as very primitive and simple organisms. These organisms spread in all seas and oceans during the Jurassic and Cretaceous periods and reached their development in the Cenozoic. Calcareous nannoplanktons found from the current Triassic period to the recent era and the benefits of their study in the fields of paleontology, paleoecology, and biogeochemistry are of great importance.
Researchers such as Jalili and Hadavi (1399); Hadavi (1387); Martini (1971); Kassler (1971) and Hilbert et al. (1981) conducted studies on the sediments of the Persian Gulf. Bioluminescence properties in seawater from bacteria that live in seawater. These bacteria are Photorhabdus, Shewanella, Vibrio, and Aliivibrio, which produce luciferase enzyme and live in the body of nannoplankton. The accumulation of nannoplankton near the shores at night causes the waters to glow. By presenting detailed studies in the fields of biology, paleontology, and microbiology, this research clarifies the role of nannoplankton in the current and past ecosystems. The purpose of this study is to investigate and understand the spread of calcareous micro-organisms in four strategic regions of the Persian Gulf and the relationship with their bioluminescence characteristics in this region.
Materials and Methods
This study was carried out in the identification of Holocene calcareous nannoplankton (Megaline) in four regions of the Persian Gulf. Eight samples were collected and studied from the surface waters of the western and southern Hormuz Island in Feb. 2018 and Feb. 2023, the beaches of Bushehr in, April 2017; the coral beaches of Kish Feb. 2018, and the west of Lawan Island in August 2021. These studies are carried out based on the determination of the species based on systematics and a series of PCR tests to investigate the bioluminescence characteristics of bacteria in BHI agar and BHI broth to determine the volume of the luciferase enzyme that causes bioluminescence.
Results and discussion
Analysis and samples of eight areas indicate that this nannoplankton can withstand high temperatures (more than 17 degrees Celsius), characteristics that were expected to be achieved due to the special weather conditions and high evaporation in the Persian Gulf.
Studies also show that many species of tropical limestones such as Coccolithus palgicus, Gephyrocapsa oceanica، Helicosphaera carteri ، Reticulofenestra minutula ،Cyclicargolithus abisectus، Syracosphaera pulchra ،Pseudoemiliania ovata، Gephyrocapsa ericsonii ،Retecapsa angustiforata و Emiliania huxleyi are present in these areas. These species help regulate carbon in marine ecosystems and play a significant role in the environmental cycle.
Among the available nannoplankton from Nannoliths, Diatomite, Heterococcoliths, and Holococcolithes, in total, 41 species from 14 genera were identified. You can also see diatoms that live in marine environments.
Microbiology and biology studies on Persian Gulf water samples have shown the presence of a group of light-producing bacteria including Photorhabdus, Shewanella, Vibrio, and Aliivibrio that live in the seas. These bacteria produce luciferase enzyme and thus produce light in the visible range. In this study, only in one of the samples related to the waters of Lawan Island, very little of the optical characteristics of these samples can be seen, and the reason for this is the inappropriate storage of the waters for the test sample.
Conclusions
This study has been conducted on the biological diversity of calcareous nannoplankton from the seawaters of four regions and eight samples of the Persian Gulf, from the western and southern Hormuz Island in February 2018 and February 2023, the beaches of Bushehr in, April 2017; the coral beaches of Kish February 2018, and the west of Lawan Island in August 2021. In this research, 41 species of 14 genera of calcareous nannoplanktons were identified, which shows the richness and biological diversity in these areas.
Species with high abundance such as Gephyrocapsa oceanica, Helicosphaera carteri, Coccolithus plagicus, and Emiliania huxleyi, Holococcolithes were observed. These findings are very important because some of these species that originated from the Paleocene or Cretaceous periods such as Coccolithus plagicus, Retecapsa angustiforata, and Braarudosphaera bigelowii are still present in the seas of the present era. They can provide valuable information on the environmental history of the Persian Gulf. Also, PCR tests were performed to determine the presence of bioluminescence agents in the samples. Despite the evidence of a small presence of light-producing bacteria such as Vibrio and Aliivibrio that produce luciferase enzyme, they exist in seawater. According to the richness of nannoplankton observed, it can be concluded that Persian Gulf waters have the highest level of primary productivity and nutrients are sufficient to support different microbial and planktonic populations

Abstract Paleosols consist of soils formed under climate conditions different from the present day, consequently their physical properties are regarded as an indicator for past climate condition. Loess investigation have received considerable attention in twenty century. Loess- Paleosol sequences in Central Aia have attracted the attention of loess researchers. Major loess areas in Central Asia are located in the southern Tajikistan. The paleosols sequences in the loess sediments in the southern Tajikistan, which can reach thicknesses of 200 m- is a key area of environmental changes of Central Asia. Loess-paleosols sequences of the southern Tajikistan prove the cold and dry climate through loess deposition and the warm and humid climate during the formation of the paleosols. Tajikistan is a mountainous country which is surrounded by mountains to the north, east and south and the desert of central Asia to the west. The climate of Tajikistan is continental, subtropical and Semiarid, with drastic changes according to elevation. The Khonako II sedimentary section studied (latitude 38.35959 N, longitude 70.04552 E) is situated in southern Tajikistan. Present-day climate in southern Tajikistan is Mediterranean, with dry summers and seasonal precipitation spanning from early winter to spring. Recently micromorplological studies have not been published from this regin. The purpose of this study were to investigate the micromorphology of loess-paleosol sequences in the southern Tajikistan as well as compare the weathering and evolution of th loess and paleosol sequences of Tajikistan and Iran. The loess-paleosol section was described and undisturbed samples were collected from thin section analyses. Thin section study of paleosols is a uniqe method to study pedological changes in the past and paleoenvironmental reconstruction. The micromorphological index of soil development (MISECA), in which several micropedological feature (microstructure, b-fabric, the presence of clay coating, decalcified zons, Fe/Mn oxides and degree of alteration of mineral grains) explain accurate infoemation of the degree of soil development in the past in different horizons. Based on increasing grade of soil Evolution, the MISECA index ranges from 0 to 24. In the studied section, a modern soil (MS) including an ochric epipedon, and cambic and calcic subsurface horizons as well as twelve loess sequences(L) and sixteen pedocomplexes (PC), which are covered by thick (∼12000 cm) loess deposits and different types of interstadial and interglacial paleosols were identified. The micromorphological investigations indicate that the accumulation of clay illuviation, pedogenic calcium carbonate and depletion of the soil carbonate are the predominant processes in these soils. Various types of calcitic pedofeatures are recognized in the modern soil which imply that coating and hypocoating of secondary carbonates around channels result from later recalcification processes. The observed voids contain of planes, vughs, channel and chamber. Channels and chambers in the modern soil, some loess units and paleosols are attributed to biological activity. The dominant microstructure of modern soil is crumb due to organic matter. The microstructure differ from waekly-separated angular (subangular) blocky in the pedocomplexes with a lower degree of development to well-separates angular (subangular) blocky in the pedocomplexes with a higger degree of development. In PC10 clay coatings super imposed on carbonate coatings, and in turn covered by calcite, demonstrates recalcification. a crystallitic b-fabric were seen in soils with a higher amount of calcium carbonate. However, the part of argillic horizons was mostly dominated by spckled b-fabric, which demonstrates the process of translocation and subsequent accumulation of clay as a result of water percolation. Clay pedofeatures were recognize as clay coating along the channels. Disruption by swelling and shrinking in soil is the main factor responsible for the lower amount or lack of clay coatings in PC1. The appearance of numerous redoximorphic features in PC7 and PC8 in comparison to the other pedocomplexes indicate periodical saturation due to higher precipitation. Generally, large amounts of clay coatings, iron and manganese oxides pedofeatures, and biological activities features indicated the high development of paleosols compared to the loess layers. Investigation of micromorphological soil development index (MISECA Index) as a measure of soil development showed weak development for modern soil, in contrast of moderately to well-developed of paleosols due to having oriented clay coatings and iron and manganese oxides on soil grains or channels. Variations of MISECA index values of modern soil compared to paleosols demonstrates that paleosols were formed in the more humid conditions.

Abstract Introduction

Mangrove forests are dynamic coastal environments where climatic conditions and water levels lead to diverse chemical, physical and biological environmental changes in different time frames, which are recorded in their sediments. In this study, physicochemical (grain size, magnetic susceptibility, total organic carbon, colour, bulk density and porosity) and biological (diversity and abundance of benthic foraminifera) data from a radiocarbon-dated sedimentary core from Azini Creek were used to reconstruct palaeoenvironmental and the relative sea level change in Sirik mangrove during the last 2700 years.



Materials and Methods

The estuaries of the Sirik region are located between 26°15' to 26°25' N and 57°4' to 57°8' E with an area of 3500 km2 in Hormozgan province, at the boundary between the Oman Sea and the Strait of Hormuz. This area is the only estuary with two mangrove trees containing Avicennia marina (Hara) and Rhizophora mucronata (Chandal). Core Az (1.5 m long) was collected within the mangrove of the Azini Creek, using a 7 cm diameter Russian peat sampler. Physiochemical and biological analysis of sediments (magnetic susceptibility, grain size, total organic carbon %, colour, porosity bulk density and foraminiferal assemblage) were performed. One radiocarbon age was determined in the Poznan laboratory by the AMS radiocarbon method.



Results and discussion

The radiocarbon age of depth 144-146 cm shows that the base of the core ages about 2700 cal. yr BP. Based on physiochemical and biological parameters the core Az was subdivided into five units of A-E. In core Az, a total of 66 foraminifera species were identified, encompassing 24 genera and 20 families. Among these species, 44 are characterized by hyaline tests, 20 by porcelaneous tests, and 9 by agglutinated tests. Sediments of core AZ are not very diverse and are all composed of sandy silt and sandy mud. Unit A is composed of olive green (5Y-5/2) sandy silt with the highest magnetic susceptibility (6.3×10-5 SI) and foraminiferal diversity (mean 17 species in 10 cm3) belonging to three groups (shallow marine environment). In unit B, sand content decreases by 50% and sediments turn to sandy mud. In this unit frequency and diversity of foraminifera decrease and porcelaneous taxa disappear (playa-lagoon). In unit C sand content (mean: 38%) and frequency of foraminifera increases again (4600). This unit represents a low mangrove adjacent to the tidal channel. In units D and E sand content decreases gradually and organic carbon and plant remains increase dramatically. Concurrence of agglutinate and opportunistic hyaline taxa suggest the provenance of mangroves in the area.

The results showed that from 2700 to 1800 years ago, the relative sea level was about 1m higher than that of today and fluvial input to the area was higher than the present. At the end of this period, the decreasing trend in the relative sea level and humidity caused the relatively humid marginal coastal environment to become a shallow playa environment. From 1400 to 1800 years ago, stabilizing the relative sea level led to the expansion of tidal channels, which provided a suitable environment for the initiation of mangroves. At this time, the gradual decrease in temperature caused a relative increase in Mediterranean winter precipitation. This climatic optimum period is traceable in other parts of the Iranian Plateau and the Near East. During the last 1400 years, the development of the mangroves began in the region. This mangrove evolution matches to the mangrove growth in the Gowatr (SE extreme of Iran) and Khuran (west of Hormuz Strait). This period coincides with the relative dryness with high climatic fluctuations. In this period gradual increase in winter temperature caused the northward migration of winter westerlies and therefore reduction in winter precipitation. This climatic deterioration is observed in other parts of the Iranian Plateau.



Conclusion

With an age of about 4000 years, the Gowatr mangrove is the oldest in Iran. 2500 years later, mangroves entered the Strait of Hormoz in Sirik and Khuran. During the last 3000 years changes in the earth's orbit around the sun caused the mean annual sea surface temperature in the Oman Sea and the Persian Gulf has increase between 2-3 degrees Celsius, which is the result of an increase in the average winter air temperature. This study shows that during warmer periods, the northward movement of winter westerly winds causes a decrease in winter precipitation in the area.





Keywords: Azini, Mediterranean winter precipitation, Chandal, Harra, Foraminifera



Acknowledgements

This investigation evolved from a research project entitled: "The history of appearance and evolution of Iranian mangroves since the Mid-Holocene and its link to the climate and sea level change", being supported by a grant from the Iran National Science Foundation (INSF) (No. 99017678).

Abstract Introduction

The subject of paleoclimatology has various aspects of study importance, one of these aspects is in the field of archaeological studies. Archaeologists need accurate and clear information about the environmental and climatic conditions of that region in the past to understand the development of cultures and the rise and fall of civilizations. Lakes provide high-sensitivity and high-resolution documents and evidence, which are required for studying climatic changes and sedimentary environments at the global level. Furthermore, aeolian deposits in lacustrine environments, because of recording drought periods and dust storms, are valuable archives of paleoenvironmental conditions. In this research, to investigate Hamoun as an important water source in the southeast region of Iran, to discover the relationship between climate conditions and several thousand years old civilization in the Shahre-sokhte.



Meterials and Methods

In the present study, besides collecting the previous data, it was attempted to sample three intact sedimentary cores with the maximum depth of 7.3 m and total depth of above 20 m, from the sediments of the lakebed by auger. Sedimentary facies were separated based on their color, grain size; sedimentary composition, grain shape, and type of evaporate minerals.



Results

Regarding the percentage of the particles existing in the sediments of Hamun's bed (depth of up to 7 m), the sediment types were determined in accordance with their frequencies as follows: slightly gravelly sandy mud, sandy mud, sand, slightly gravelly sand, muddy sand, mud, gravelly mud, muddy sandy gravel, sandy silt, silty clay, and clay. Sorting the aeolian sediments was obtained through IGSD equal to 0.75, which was located in the moderate-to-good range. The average skewness in sediments of the taken cores was 0.15, which indicated skewness toward very fine particles. Also, the average kurtosis for the sample taken from pneumatic sand zones was equal to 1.3 (kurtic). The variations in the values of the parameters of some of the samples were due to the combination of different aquatic and aeolian processes in some parts of the sandy zones. Furthermore, the presence of the sediments with moderate to good sorting as well as kurtosis and skewness toward the very fine-grained particles indicated the supply of sediments mainly with aeolian origin and, in some cases, with fluvial origin.



Discussion

As previously mentioned, activity of the dominant winds of the region is from north toward northwest. Existence of the heights in the west of Hamun, which sometimes reaches 1700m, acts as an obstacle against the dominant winds. In this regard, existence of Rudbandan Valley can act as a channel for the passage of the winds, and reinforce and channelize the winds. This factor can also justify the high thickness of the aeolian sediments at the crater of Rudbandan delta (core H-2). Another effective factor is the feeding of Helmand and Sabari hamuns by rivers of the drainage basin (Helmand and Farah rivers). The sediments of Hamun's lakebed demonstrate the dominance of the aquatic facies; however, such conditions are more prominent for Hamun-e-Helmand due to the great area of the drainage basin and high water volume of Helmand River. Therefore, we can see the alternation of the lacustrine facies (with dominant thickness), fluvial facies (sediments of river channel), and aeolian facies in the core H-3, which are reduced along the sediments toward the cores H-1 and H-2 and is gradually converted into the marginal lacustrine and fluvial (mainly floodplain) as well as aeolian environments (especially in the core H-2). In the core H-2, due to the low area of the drainage basin of Rudbandan, low sedimentary input, and high intensity of the dominant winds, the aeolian sediments are dominant. It seems that the sedimentation rate in the late-Holocene drought period has been very high due to the high volume of the aeolian sediments, or probably no intense erosion has occurred after the sedimentation. In other words, after the drought 4.5 ka BP in Hamun, no intense drought with severe erosion has occurred. The windiness conditions of the region in the late-Holocene have been comparable to the current 120-day winds. However, the case is different for the aeolian sediments found at the depth of 4.5 m, which is equivalent to the drought event of 800 BP and has coarser grains and less thickness. It seems that, due to the high intensity, the power of carrying has been very high, and probably again influenced by erosion after the sedimentation so that a part of the sediments has been re-carried while leaving slight thickness (40 cm). The presence of the sequence of aeolian sediments and lack of plant and animal relicts imply the complete drying of the lakebed in a certain period so that, in this period, sedimentation of the aeolian deposits has been catastrophically concordant with the sedimentation of the silty and muddy deposits of the floodplain sediments.

The existence of brown-colored coarse-grained pneumatic sand particles during the early to mid-Holocene period (8.2 ka BP) indicated the occurrence of intense storms in Sistan Basin. Sequence of the fine- and very fine-grained pneumatic sands at the depth of 2.5 m represented the presence of the winds similar to the current "120-day winds" in Sistan plain. Moreover, in this study, two major drought periods (8.2 and 4.5 ka BP) were identified in Holocene sediments of the lakebeds of Hamun-e-Helmand and Hamun-e-Sabari, which indicated drying and expansion of the aeolian sediments on Hamun's lakebed. The subject of paleoclimatology has various aspects of study importance, one of these aspects is in the field of archaeological studies. Archaeologists need accurate and clear information about the environmental and climatic conditions of that region in the past in order to better understand the development of cultures and the rise and fall of civilizations. One of the important issues in this regard is the role of environmental changes over time and its impact on human livelihood and settlement. The decline of the ancient civilization of the burnt city, it shows a good correspondence with the dry period 4500 years ago. Which lasted about 500 to 700 years.

Abstract 1-Introduction
Global warming refers to the recent and ongoing rise in global average temperature near Earth's surface. It is caused mostly by increasing concentrations of greenhouse gases in the atmosphere. Global warming is causing climate patterns to change. However, global warming itself represents only one aspect of climate change. (Nakicenovic et al., 2000; Bytnerowicz et al., 2007).
Over the past century, human activities have released large amounts of carbon dioxide and other greenhouse gases into the atmosphere. The majority of greenhouse gases come from burning fossil fuels to produce energy, although deforestation, industrial processes, and some agricultural practices also emit gases into the atmosphere.
Greenhouse gases act like a blanket around Earth, trapping energy in the atmosphere and causing it to warm. This phenomenon is called the greenhouse effect and is natural and necessary to support life on Earth. However, the buildup of greenhouse gases can change Earth's climate and result in dangerous effects to human health and welfare and to ecosystems. 

2-Materials and methods
In this study, daily precipitation and daily maximum (Tmax) and daily minimum (Tmin) temperatures in the Kahnuj synoptic station, southeastern Iran were predicted for the future (2061-2080) by statistical downscaling outputs of 5 GCM models (EC-EARTH, GFDL-CM3, HadGEM2-ES, MIROC5, MPI-ESM-MR) under RCP 4.5 and RCP 8.5 emission scenarios.

3-Results and discussion
The results of statistical downscaling outputs of 5 GCM models by LARS-WG model under RCP 8.5 emission scenarios (the business-as-usual) in Kahnuj station was modeled from 2061–2080. During this period the mean temperature will increase between 3.2 to 4.6 °C compared to the base period.
At The Paris Agreement, the average increase in temperature was set at below 2 °C by the end of the 21st century, which includes the 0.9 °C increase Since the Industrial Revolution, to avoid adverse and unpredictable weather effects (IPCC, 2021; Millar et al., 2017; Rogelj et al., 2018). However, the results of this study show that southeastern Iran is firmly set on the path by increasing the current temperature by several degrees more by 2080. Based on the two modeled scenarios, the change in temperature will have an increasing trend in the coming years and is in good agreement with the recent assessments of future temperature changes in southwest Asia (Babar et al., 2016; Hamidianpour et al., 2016; Pal et al., 2016; Evans, 2009). Therefore, if greenhouse gas emissions continue at their present rate, earth's surface temperature in this region will pass the temperature threshold of 2 °C.

4- Conclusion
We compare simulated future precipitation based on RCP 4.5 and RCP 8.5 scenarios of global warming with real paleoclimatic changes that happened in the region. In this respect, the maximum and minimum temperatures and precipitation projection in the southeastern Iran is derived from the downscaling of the CMIP5 GCMs (EC-EARTH, GFDL-CM3, HadGEM2-ES, MIROC5, and MPI-ESM-MR) under RCP 4.5 and RCP 8.5 using the Lars WG model. Paleoenvironmental records from southeastern Iran is used to examine whether the predicted changes in precipitation and variability in MLW output based on the two scenarios of global warming are valid.
GCMs predicted a considerable decrease in MLW precipitation in Kahnuj station. Similarly, HadGEM2-ES and GFDL-CM3 indicate a weak decline in precipitation compared to other GCMs at the Kahnuj station for RCP 8.5.
The current study indicates that in the Jazmurian playa, MLW precipitation will decrease, and temperature will increase in future simulations. Infact, Consistent with several GCM studies and real paleoclimatic changes that happened during past warm/wet periods in the region, results emerging from the Jazmurian playa also show a weakening of the MLW under the RCP 8.5.

Abstract Introduction
Climate, as the average temperature or precipitation over a long period of time, has been constantl  fluctuating and changing, and there is no simple relationship between climate change and human biological and cultural reactions.Understanding the environmental characteristics of the past is important to understand climate changes.Climate changes are reflected in the physical and chemical characteristics of sediments, which can be used to understand sedimentary processes and ancient sedimentary environments.In the meantime, the sediments of playa lakes are sensitive indicators of local climates And due to the influx of large volumes of sediments during floods and as a result of the high rate of sedimentation, it is possible to record climatic and environmental changes with high resolution. Jazmurian playa in the southeast of Iran consists of sand, mud and salt flats. Over time, under the influence of water and wind processes, Jazmurian has left various deposits in deltaic, lake, playa and wind environments.

Materials and methods
Jazmourian plateau between latitudes 58˚-40' to 59 ˚-14' and latitudes 27˚,10' to 27 ˚, 41' in southeastern Iran and west of Sistan and Baluchestan province and east of Kerman province. It is located at an altitude of about 360-500 meters above sea level. The catchment area is about 69,600 square kilometers, of which about 34,160 square kilometers are mountainous areas, 32,440 square kilometers are plains and foothills, and the remaining 3,000 kilometers are swamps and salt marshes. For this study, intact sediment cores were used to reconstruct the Paleo climate. Five sedimentary cores with a maximum depth of 7 m and a total depth of about 30 m were collected and investigated from the sediments under of different areas of Jazmourian Playa using a hand-held core. Sedimentary facies were identified and distinguished based on sediment texture and composition, composition of destructive sediments and organic matter, color, presence of plant and shell residues, and other macroscopic components. According to sedimentological studies and changes in sedimentary facies, eight separable sedimentary facies belonging to river, playa, lake, delta and wind environments were identified. To estimate the time of climatic events in the region, the results of the survey of Vaezi et al. (2019) were used.

Results and Discussion
In order to reconstruct the environmental and climatic conditions of Jazmurian playa by using the geochemistry of sediments, 5 sediment cores were taken from the inner part of the playa. Coring was done by manual auger to a depth of about 7 meters. In taking the cores, the changes of sedimentary facies were recorded based on macroscopic evidence such as the type of layering surfaces, the geometric shape of sediments, sedimentary structures, animal remains and contents, plant remains, the presence of evaporite minerals, the relative degree of hardness, color and its changes. Reconstruction of the spatial distribution of different sedimentary environments and their displacement and conversion to each other was done based on the data of sedimentary cores in different areas and finally the stratigraphic column of the studied cores was drawn. Half of the collected samples were taken to the laboratory for preparation and chemical analysis, and the other half was archived at 4°C. A total of 19 sediment samples from a core (comprehensive core) were sent to the laboratory of the Geological and Mineral Exploration Organization of the country for chemical analysis. Varian 735-ES model ICP-OES (ICP Optical Emission Spectroscopy) device was used for elemental analysis and the results of the anomaly level of 54 other elements in terms of ppm were identified by the ICP device. In the studied cores, the relative changes of elements in different time periods are very high, this situation indicates the presence of severe changes in the sedimentary sequence of Jazmurian playa bed. This study provides a breakdown of environmental and climatic changes in the southeastern region of Iran during at least the last 20 thousand years. In this research, climatic and environmental events have been identified in the sedimentary sequence taken from Jazmurian playa according to elemental anomalies and 8 elemental ratios. The elemental ratios of Mn/Al and K/Al as an indicator of chemical weathering changes in the watershed in the period of 20 thousand years are changing between 0.0154 to 0.0135 and 0.226 to 0.252, respectively. An increase in these ratios indicates the existence of favorable conditions for increasing the amount of chemical weathering in the watershed and a corresponding increase in humidity and temperature, and its decrease indicates the presence of dry conditions in the basin.

Conclusion
Sedimentological investigations, statistical parameters of sedimentology and sedimentary facies of the cores taken from Jazmurian playa led to the identification of five sedimentary environments including wind, fluvial, deltaic, lake and playa sediments in Jazmurian basin. The sedimentation rate in Jazmurian playa is different in different depths, this rate reaches 0.01 mm per year in the surface parts. The average sedimentation rate in Jazmurian playa is about 0.4 mm per year. V/Cr, Mn/Al, K/Al, Fe/Ca, Ti/K, Ca/Mn, Ca/Sr, Fe/Al element ratios to reconstruct the climatic and environmental conditions, the amount of debris (clay sediments and wind deposits) The input to the basin, the severity of weathering and erosion in the catchment basin and the fluctuations of the lake water level indicate the climatic condition of Jazmurian region in two time periods. The time period of the late Pleistocene when suitable humid conditions prevailed. During this period, the amount of chemical weathering in the catchment area and sediment load to the playa has been significantly high. Since the beginning of the Holocene, climatic and environmental fluctuations have increased in the basin, and until the beginning of the middle Holocene, there has been a gradual decrease in humidity, with the beginning of the middle Holocene, this process has accelerated, and wind-blown sands have entered the northern and western parts of Jazmurian playa. From the beginning of the middle Holocene until now, according to the investigation of sedimentary facies and elemental ratios, at least two dry periods in 8200 and 4200 years ago can be identified and traced.
 

Abstract Introduction

Lake basins have spatially and temporally index patterns and represent valuable maps of physical and chemical history. According to this point, that direct survey of climate changes has only been available as machinery in the past few decades, so past’s climate changes indexes can give a better understanding of climate changes in the past era and its causes. Of these, lake sediments have an extraordinary ability to record climatic and environmental events with high sensitivity and resolution and very high- resolution amounts. Therefore, lake sediments can be considered as regions for detecting paleontological environments. Abzalou lake formed in the northeast of Khuzestan province on the hillsides of folded Zagros and under the Izeh unit in a pit. This study has been tried to by Sedimentary geochemistry examination, Elemental ratios, identification of sedimentary facies, identification of sedimentary environments and changes of these environments set to the reformation the climatic and environmental conditions of Abzalou wetland in the end Holocene.

Methods and Findings

The steps of this research include book studies, field works, laboratory works, data processing and then interpretation and conclusion. To investigate the paleontological climate and conditions of the sedimentary environment, 8 intact sediment cores with a maximum depth of 7.5 m and total of 35 m collected with using Auger corer. 36 sediment samples from 2 cores were selected for elemental analysis with ICP-OES and XRF (X-Ray fluorescence). Also, 3 samples were analyzed by C14-AMS isotopic method. Statistical parameters, histogram diagrams of element frequency and cluster analysis were performed to determine the relationship between the elements in SPSS software. In this study, according to the studies, elemental ratios of V/Cr, Mn/Al, K/Al, Rb/Al, Si/Fe, Ti/K were used to reconstruct the climatic and environmental conditions. Which led to the study of the amount of detrital material, the severity of weathering and erosion in the catchment and fluctuations in the water level of the lake.

Results and discussion

In the studied cores, 8 major sedimentary facies identified. Facies often contains clay, silt, sand, gravel, and interstitial sediments along with vegetation and shell fossils which in most cases frequency and interference in the mentioned sediments are often seen. Changes were in particle size between clay to gravel due to process type changes, environment's energy and river input's amounts and sediment color variations concerning sedimentation conditions, presence of organic matter, pH amount, salinity and temperature variations, and drought occurrence, throughout the cores. Three wetland sedimentary, river and alluvial environments identified. According to the age measurement, the average sedimentation rate in the Abzalou wetland is 1.22 mm / year, which this amount is different for various depths. Due to the type of sediments, the Abzalou wetland has undergone human changes for about 600 - 500 years ago. The high water period of the Abzalou wetland has been established between 1800 and 500 years ago. The study of the facies sediments of the wetland bed shows that climate change occurred gradually (not suddenly) about 1800 years ago and this trend has taken at least 200 years. The relatively dry period lasted about 700 years from 2500 years to 1800 years ago and is confirmed with the reported dry periods in the Maharlou lake about 1800 years ago, in the Mir Abad lake about 1500 years ago and in the Urmia lake between 2500 and 1500 years ago. From 4400 years ago to about 2500 years ago, stable and slow wetland conditions prevailed. The conditions for creating a peatland environment have been provided in the wetland and were associated with increasing the amount of organic matter, vegetation and shell fossils and consequently increasing sedimentation rate. This period which lasted for about 1900 years, has been accompanied by extremely humid conditions, high groundwater level and activity of springs feeder in the region. The existence of light brown mud which has the age ranges from 4400 to 4700 years ago, indicates a dry period (300 years). This dry period shows suitable approximate conformity with a dry event of 4200 years ago in the northern hemisphere. This period in the studied region appeared with at least 200 years of temporal delay. After this dry period, we see again a gray sequence with plant and shell fossils that continue to a depth of 7 meters (about 5300 years ago). At depths of 7 to 7.5 m, the existence of brown-muddy sediments along with coarse-grained sediment in size of gravel, pebble and rubble, strengthen the possibility of very strong flood in the region that sent the coarse-grained sediments of around formation to bed of the wetland or maybe has hit to the area of wetland sediments bed in the region.

Conclusion

According to the results of surveys in the Abzalou wetland, at least 3 high water periods with humid climate and at least 2 dry periods during the Late Holocene were identified.  Dry periods appear more suddenly and with more intensity and shorter duration than humid periods in the region and gradually lead to from very dry periods to semi-arid, semi-humid, and eventually humid periods.
 

Abstract Introduction
Paleoclimate is a new branch of science that investigates the climate changes of the past by using different sciences. Carbonates are a type of rocks that have been studied a lot in the geochemistry of stable isotopes and are found in all time intervals. A common type of carbonate rock is speleothem, which is capable of providing reliable records of climate change over many years. The studies conducted in the last decade show that the past climate can be understood by δ¹⁸O and δ¹³C. One of the common forms of speleothem is stalagmites, whose layers are known as a potential source of high-quality climatic information. By using speleothem, it is possible to reconstruct the climatic conditions up to about 600 thousand years ago. Comprehensive and complete information is not available about the climatic and environmental conditions of Iran during the Holocene period. Meanwhile, Iran's location as a transition zone between Europe, Asia and Africa is of great importance for study the past climate; However, compared to other regions, it has been less studied, which has provided a special position for this research. In the present research, it is intended to be analyzed with the help of the information received from a cave in the Zagros region of the past climate of Iran.

2-Materials and methods
For paleoclimate analysis in central Zagros, Maghar cave in Khorramabad (located in Lorestan province and in Karkheh watershed) was selected. The condition of this cave is such that it has little connection with the environment outside the cave and is not affected by the wind and other meteorological parameters outside the cave. After evaluating inside the cave, a stalagmite with a length of about 18 cm and a diameter of 8 cm was selected. After cutting it, it was transferred to the soil mechanics laboratory of Lorestan University, where its surface was polished in order to observe the layers. Since the primary core of the stalagmite is not located right in the center, it can be concluded that the primary bed of stalagmite formation is located on a sloping surface, which caused the drop of water to move on the sloping surface after hitting the surface of the cave. As the limit has increased in length, it has grown in width. For dating, three points were considered, including the stalagmite primary core (D1), middle (D2) and on top of it (D3). Age measurement was done by Multi-Collector Inductively Coupled Plasma-Mass Spectrometer (MC-ICP-M) located in the laboratory of the University of Queensland, Australia. For stable isotope analysis, 34 samples were sent to Arak laboratory for δ¹³C and δ¹⁸O analysis, and the analysis was done by Isotope Ratio Mass Spectrometer (IRMS) (30 samples in the direction of stalagmite growth length and 4 other samples for Hendy test). According to the standard of this device, 50 mg of powder was prepared for each sample. This was done with the help of a dental drill and movement on the stalagmite layers. To determine the percentage of calcite and aragonite, 4 samples (50 grams each) were sent to the laboratory of Lorestan University for XRD testing.

3-Results and discussion
According to the XRD results, the percentage of aragonite was considered zero for all four samples. According to the Hendy test, stalagmites are formed in isotopic equilibrium conditions. The age of three samples was estimated to be 550, 368 and 8.6 thousand years respectively. The analysis of δ¹⁸O isotopic results over time showed that the isotopic data is increasing with a relatively large slope, which indicates that the conditions of the studied area during the last 550 thousand years are becoming drier and reducing precipitation.

4- Conclusion
Climatic periods are always changing and dry and wet periods have occurred on a larger scale in the form of glacial and interglacial periods. In the past, these changes happened very slowly, but in the last 5 thousand years, the changes are fast. These changes intensify over time. So that there have been sudden changes in the last hundred years. Today, climate change is not hidden from anyone, but unfortunately, it has not been found in a suitable solution. Many countries use different methods to prevent the damages of climate change in the future. It is clear that disturbing the order of nature disturbs the balance. Further research similar to the present research can tell the past climate in more detail.

 

Abstract 1-Introduction
Climate change refers to any significant change in the existing mean climatic conditions within a certain time period (Jana and Majumder, 2010; Giorgi, 2006). Earth's climate change through history has happened (Nakicenovic et al., 2000; Bytnerowicz et al., 2007).

2-Materials and methods
In this study, daily precipitation and daily maximum (Tmax) and daily minimum (Tmin) temperatures in the Iranshar synoptic station, southeastern Iran were predicted for the future (2061-2080) by statistical downscaling outputs of 5 GCM models (EC-EARTH, GFDL-CM3, HadGEM2-ES, MIROC5, MPI-ESM-MR) under RCP 4.5 and RCP 8.5 emission scenarios.



Figure 1: Major climate systems over West Asia (Gurjazkaite et al., 2018; Sharifi et al., 2015; Vaezi et al., 2019). and location of the Iranshahr station (marked as a red box). A) . Dotted lines indicate the approximate current location of the Intertropical Convergence Zone (ITCZ), Mediterranean winter precipitation zone lying between the dashed lines, and the Siberian Anticyclone; IOSM refers to the Indian Ocean Summer Monsoon, and a 30 years average of minimum and maximum monthly mean air temperature (°C) and mean monthly rainfall (mm) as recorded at Iranshahr.

3-Results and discussion
The results of statistical downscaling outputs of 5 GCM models by LARS-WG model under RCP 8.5 emission scenarios (the business-as-usual) in Iranshahr station was modeled from 2061–2080. During this period the mean temperature will increase between 3.2 to 4.6 °C compared to the base period.
At The Paris Agreement, the average increase in temperature was set at below 2 °C by the end of the 21st century, which includes the 0.9 °C increase since the industrial revolution, to avoid adverse and unpredictable weather effects (IPCC, 2021; Millar et al., 2017; Rogelj et al., 2018). However, the results of this study show that southeastern Iran is firmly set on the path by increasing the current temperature by several degrees more by 2080. Based on the two modeled scenarios, the change in temperature will have an increasing trend in the coming years and is in good agreement with the recent assessments of future temperature changes in southwest Asia (Babar et al., 2016; Hamidianpour et al., 2016; Pal et al., 2016; Evans, 2009). Therefore, if greenhouse gas emissions continue at their present rate, earth's surface temperature in this region will pass the temperature threshold of 2 °C.
One of the mechanisms contributing to the poor monsoon rainfall simulation in CMIP5 and HadGEM3 models may be the Arabian Sea cold sea surface temperature biases that persist until summer and reduce moisture fluxes over the Arabian Sea (Levine et al. 2013; Levine and Turner 2012). In modern times, IOSM induced upwelling of cold water leads to reduce sea surface temperatures in western Arabian Sea in summer that in turn cause reduced evaporation over a cooler Sea and less moisture in the low-level monsoon jet (Levine et al. 2013; Saher et al. 2007). In order to evaluate this hypothesis, paleoclimate changes discussed in the southeastern Iran is useful. The multi-proxy climate record from southeastern Iran reveals that the regional hydrology of southeastern Iran since ca. 14.7 cal kyr BP is primarily governed by IOSM strength, which is linked to the position of the ITCZ in response to the orbital-scale changes in summer insolation (Fleitmann et al., 2007; Gupta et al., 2003; Overpeck et al., 1996).

4- Conclusion
As the first comprehensive (both future and paleo) climatic change study in the arid region of southeastern Iran on the north most border of IOSM, we compare simulated future precipitation based on different scenarios of global warming with real paleoclimatic changes that happened since ca. 14.7 cal kyr BP in the region. In this respect, the maximum and minimum temperatures and precipitation projection in the southeastern Iran is derived from the downscaling of the CMIP5 GCMs (EC-EARTH, GFDL-CM3, HadGEM2-ES, MIROC5, and MPI-ESM-MR) under RCP 4.5 and RCP 8.5 using the LARS- WG model. Paleoenvironmental records since 14.7 cal kyr BP from southeastern Iran is used to examine whether the predicted changes in precipitation (variability in IOSM and MLW output) based on the two scenarios of global warming are valid.
we postulate that results of statistical downscaling outputs of the GCMs by LARS-WG model in Iranshar synoptic station did not have a sensitivity to simulate monsoon precipitation in this complicated region with various factors impacting climate change. Because the results dose not match the paleohydrological changes and Intensify of IOSM during past warm periods. We suggest, in the new generation of climate models, the effect of a consistent increase in seasonal mean precipitation during the summer monsoon under warming scenarios must be considered more for north most monsoonal domain area like southeastern Iran.
 

Abstract Introduction
Paleoclimatology studies attempt to detect climate change over time and fill meteorological data gaps in a variety of ways. One of the most widely used methods in Paleoclimatology and the reconstruction of climate data for decades and centuries is the use of tree rings. Trees, by forming annual growth rings, store past climate information, and dendroclimatological studies reveal this valuable information to us. One of the suitable species for these studies is the Juniperus tree, of which there are significant habitats in the study area - northern elevation of Kerman province. Considering the simultaneous effect of short-term and long-term water sources on annual tree growth, the aim of this study is to investigate the effect of different water sources on tree growth in the study region and then reconstruct rainfall conditions using annual growth rings of Juniperus trees in the habitat that is called "Tangal Ravar" in the north of Kerman province.

Materials and methods
 "Tangal Ravar" Juniperus habitat is located in the northern highlands of Kerman province, at the 31°25' of North and 56° 50' of East. The highest peak of this mountain is 3515 meters above sea level, Juniperus trees in these heights are mostly distributed on the southern, southwestern and western slopes from 2700 to 3100 meters. Examination the data of climatic stations close to this habitat showed that the annual rainfall is about 200 mm and the average temperature is 20 degrees, which emphasizes the location of the habitat in semi-arid regions. The Precipitation regime in habitat is at cold season from November to April, and the habitat growing season lasts from about mid-March to late September.
Sampling was performed in spring 2018. For this purpose, an increment borer with a diameter of 5.5 mm for hardwood was used. About 200 samples were taken from 96 trees that were as healthy and undamaged as possible. The rings were counted and their width was measured with LINTAB desktop and TSAPWin software with an accuracy of 0.01 mm. The cross dating between the growth curves of the trees was done with TSAP software and the results of GLK, CDI, GSL, CC and Tv statistics showed the desired quality of the that for most of the trees. Chronologies were created in ARSTAN software by BiweightRobust averaging method, and then de trending and standardized by negative exponential curve method and 20-year spline, and finally STANDARD chronology was selected for studies. The quality of chronology was measured by the mean correlation statistics of all habitat trees (Rbt), Expressed population signal (EPS), signal-to-error or anomaly ratio (SNR), mean sensitivity (MS), and Autocorrelation (AC1). Then, the relationship between climate and ring width was measured using station data from Kerman province and CRU TS4.01 climate data for the last 116 years in Iran by Pearson correlation coefficient and precipitation reconstruction was performed using simple linear regression.
Result and discussion
  The quality studies of chronologies results showed that the longest chronologies prepared are 680 years (1338-2017 AD) with a confidence reconstruction period of 252 years and the chronologies have desirable values of quality measurement statistics. The average chronology of the region shows a relative decrease in the width of growth rings in the last two decades with a decreasing trend in the last century along with increasing fluctuations in the 1950s and 1980s. In general, we can see a decreasing trend in the width of the rings from 1500 to 1650 AD, an increasing trend from 1650 to 1750 AD, a decreasing trend from 1750 to 1800 AD, an increasing trend from 1800 to 1900 AD with an obvious decline in the 1850s and the trend Observed a decline from 1900 to the present. The study of the correlation between rainfall and the width of growth rings of juniper trees in "Tangal Ravar" habitat, which is a mountainous region with semi-arid climate, showed that rainfall before the growing season and the beginning of the growing season, or in other words, total annual rainfall is the most important and effective factor in the width of the rings. Also, the total rainfall of the coldest months (November, December and January) shows a high correlation with the width of the rings. The results of rainfall reconstruction also showed several droughts and wetlands along with fluctuations in ring width.
Conclusion
The results showed that precipitation in general has a direct relationship with the width of the growth rings of juniper trees in the region. Meanwhile, December-January precipitation due to snowfall and total precipitation of the rainy season, ie October-May, shows a high correlation with the width of the rings. Due to the high slope in the topography of the habitat, the rocky location of most trees, shallow soil and consequently low groundwater storage, juniper trees of "Tangal Ravar" habitat depend on the amount of rainfall before the growing season and the beginning of the growing season in the region. Due to the mountainous nature, most of the winter precipitation in the region is snow. Considering the high positive correlation between December-January and for some stations December-January-February, it can be said that snow storage before the start of the growing season plays an important role in the width of the growing rings of all habitat trees. Considering the reconstructed precipitation, the significant periods of drought and wet years in the region can be summarized as follows: Droughts of the last two decades, especially from 2007-2006 to 2017. Drought of 1980s, Drought of 1965-1975. Wet period of the 1950s, droughts of the 1940s, droughts of 1916-1919, wet period of the second half of the nineteenth century with a severe drought in the 1870s, a decrease in precipitation over a century from 1850 to 1750 with multiple droughts, increased precipitation in the period 1750-1700 AD with continuous wetlands. An obvious and continuous decline for 170 years from 1700 to 1520 AD. Among these, the important droughts of 1916-1919 and 1870-1871, which were accompanied by severe famines in Iran, have been mentioned in the results of other researchers.
 

Abstract Gastropoda and Bivalvia as Mollusks are invertebrates which have a layer made of calcium carbonate for protecting their soft bodies known as shell. One layer is added to the shell in each stage of growth, like annual rings in a tree. These circles are formed dark or light as well as strong and weak layers. Researchers are trying to find out reasons and conditions of improvement and acceleration or stopple of growth. This field of science known as sclerochronology, can be used to analyze the growth bands of shells. Materials for producing the shell have been absorbed from environment. Therefore, information of environmental and growth conditions have been saved on these layers.The information is resulted from the data in the shells through sclerochronological studies. Therefore, sclerochronological methods are one of the best scientific methods with high accuracy that allows the study of animal growth conditions as well as environmental and climatic changes. These studies as one of sclerochronological methods are known as sclerochemistry. In the last few decades, sclerochronological methods have been considered by researchers in other fields, including paleontologists and archaeologists, in addition to biologists. Contrary to its importance and precision for study of environmental conditions and climatic variation in the past, it is unknown to many researchers. On the other hand, even after the 1940s and the invention of the term sclerochronology, many researchers who had previously used this method to evaluate their hypotheses, especially in oceanography and marine biology, to determine age, growth pattern, and aquatic conditions, have not used the term sclerochronology in their reports. This is the most important reason why sclerochronology remains unknown among researchers. In addition, in sclerochronology we encounter different species of organisms. It makes challenging differences in the study process of growth pattern or sampling for isotopic analysis and access to environmental information. Also, some Species that can be examined are not suitable for answering all the questions. Although, this capability may be lost in some approved species over time and therefore they are no longer suitable for analysis.There are even species that only certain parts of them can be examined. Some cases have made it difficult for new researchers to study related methods, and have limited their studies. This article tries to characterize an important part of these problems by reviewing the background and literature of sclerochronology and sclerochemical methods for reconstruction climatic conditions through library studies.
 

Abstract Introduction
The study of tree rings is one of the most widely used methods of climate reconstruction for centuries and millennia, but the occurrence of climatic anomalies such as global warming in recent decades has caused divergence problem in the series of tree rings in some areas. Which challenges the ability of this proxy to regenerate the climate. The “divergence problem” is the difference between the recorded temperatures and the regenerated temperatures using tree rings in the forests of the northern high latitudes. While the data recorded by thermometers show a significant warming trend in the late twentieth century, many of the chronologies obtained from the sites mentioned do not show a similar change in ring width. Reconstruction of past temperatures in divergent chronologies overestimates past reconstructed temperatures. The present study tries to investigate the occurrence of "divergence problem" in low latitudes using juniper growth rings in the north of Kerman province in Iran and provide a solution for temperature reconstruction according to the chronologies with this problem.
Materials and methods
The study area of this study is one of the lesser-known habitats called “Tangal Ravar”, located in the northern highlands of Kerman province in Iran at the 31°25' of North and 56° 50' of East. In the spring of 2018, more than 200 tree ring samples taken of juniperus trees. Chronologies created in ARSTAN software by BiweightRobust averaging method, and then de trending and standardized by negative exponential curve method and 20-year spline, Climatic data were prepared from two synoptic stations of Kerman and Zarand to investigate the relationship and correlation of climatic factors with the ring width index and reconstructions. For better comparison of these two stations, CRU TS4.01 data with the statistical period of 1901- 2016 for Iran, also used. In this study, two methods used to reconstruct the annual temperature. In the first method, first the temperature threshold (according to CRU temperature data) is determined and then by dividing the years, from data above the threshold to construct a regression relationship of the divergence period with inverse correlation and from data below Thresholds were used to construct the regression relationship of the pre-divergence period with direct correlation. In the second method, multivariate regression used between temperature data, ring width and precipitation for the statistical period of 1901-1995. The reconstructed precipitation used for multivariate reconstruction until the end of the chronology.
Result and discussion
The results of comparison between temperature data and tree rings chronology index of the studied habitat showed that the trees of this habitat have been suffering from divergence since the mid-1990s. Initially, the results of correlation between station temperature data and average chronology of the region showed a generally negative relationship and it concluded that air temperature throughout the year has a negative correlation with the growth of juniper trees in the region and in general, this factor is a limiting factor. , But this is not consistent with most research on the subject. Temperature reconstruction in this case showed an inverse function of the chronology chart trend due to the negative relationship. Therefore, using a negative relationship to reconstruction temperature over a long period led to meaningless estimation during periods of severe reduction in rings width. However, with the removal of the 1996-2016 period from the data series, the correlation results underwent extensive changes to positive. The results showed that in years with an average temperature between 17 to 17.5 degrees and sometimes from 16.8 to 17.8 degrees, there is no significant relationship between the width of the rings and the temperature, and this temperature range can be considered without regard to taking the role of precipitation, the optimal growth temperature. At temperatures below 17 or possibly 16.8 degrees there is a direct correlation and at temperatures above 17.5 or possibly 17.8 degrees there is an inverse relationship between growth and temperature. In addition, comparison of chronology with climatic trends showed that precipitation has a more decisive role in the radial growth of juniper trees. In this regard, the reconstruction results showed that the use of bivariate regression and the application of precipitation for the second variable, despite the smoother data estimation than the real data, in general show better results than data segmentation based on temperature threshold.
Conclusion
Examination of station temperature data with chronology obtained from the region showed that due to the increase in temperature along with the relative decrease in precipitation in recent decades, temperature data with the chronology of ring width have diverged. Therefore, in order to reconstruct the temperature and study the climate / growth relations in the region, it is necessary to carefully study the relationship between This divergence for the study area has clearly started in 1996 and has continued until the end of chronology in 2017, for more than the last 2 decades. The time difference between the occurrence of the "divergence issue" in the study area and the northern areas is about 40 years. This issue can be related to the occurrence of later increase in temperature averages in the study area compared to high latitudes and the greater impact of juniper trees in arid regions such as the north of Kerman province from moisture. So that the increase in air temperature alone is not able to limit the radial growth of juniper trees and the creation of moisture stress is necessary for this issue, this stress has obviously occurred since 1996 with successive droughts in the region. The results showed that due to the location of the study site in a dry area, the use of precipitation as a second variable gives better results for temperature reconstruction. Finally, the regenerated temperature shows an increase of about 1.5 degrees in global warming in recent decades. In addition, except for an increase in the decades 1740-1750-1760, a decrease of 0.5 to 1.5 degrees of temperature compared to the long-term average from about 1820 to 1520 AD can be considered the reaction of juniper trees in the region to the Little Ice Age.
 

Abstract Introduction
Reconstruction of past climate change can provide us valuable information about the time, scale, and details of climate changes. For reconstruction of late quaternary climatic conditions, various methods are used, as well as the use of losses, paleomagnetism, paleontology, etc.One of these methods is to use stable isotopes of carbon and oxygen, which is particularly valuable information on the temperature of the depositional environment, digenesis temperature, the temperature changes in different digenesis environments, separating different areas carbonates offers Considering the importance of Gorgan Bay from different aspects and the fact that not many studies have been done in this region regarding long-term climate change, in this research we have tried to use different data obtained from sedimentary cores harvested from the southeastern part. Caspian Sea (Gorgan Bay) Temperature changes and environmental conditions of the region in the late Quaternary to be studied and reconstructed.
Gorgan Bay with an area of more than 400 km is located in the southeastern part of the Caspian Sea (36°48’N, 53°35’E and 36°55’N, 54°03’E, 60 km ×12 km, maximum depth of 4 m ). Gorgan Bay formed during the Holocene period by a sandy spit which is named Miankaleh coastal barrier system. It is connected to the Caspian Sea through the inlet of Ashoradeh-Bandar Torkaman (Chapaghli) which is located in the northeastern part of the Bay This bay is mainly influenced by processes that are operating within the basin. Water balance in the Gorgan Bay is influenced by freshwater inflow from a number of small rivers and streams, including Gorgan-roud from the north and QarehSu from the east. These two rivers drain runoffs from residential and agricultural areas into the bay.
 
Materials and methods
In this for reconstruction of late Quaternary climatic conditions a sedimentary core (N1) were collected from Gorgan Bay using a gravity corer. The core was first examined for magnetic susceptibility (MS). After slicing the core and subsampling with certain distances, Laser particle size analyzer used (Horbia LA-950) for grain size analysis. Also to specify total organic matter content (TOM), loss of ignition method (L.O.I) was used. For this purposes, a portion of each sample (about 3 gr) was placed inside a crucible and heated at 550 ° C for 5 hours and after that the weighing percentage of the organic material was reported. For measurement of carbonate content (CaCO₃%), coarser grain particles were manually removed and remaining sediments were placed in a muffle furnace (Excitation, EX.1200-12L) for 1 hour at 950 °C . For ¹⁴C dating, totally 3 organic matter samples were sent to the Poznan Laboratory, Poland, The oxygen and carbon stable isotope analysis was carried out on the non-digenetic and negligible digenetic benthic foraminifera (Ammonia Beccari) by mass spectrometer in the Winsor Laboratory, Canada. Paleotempreture of the seawater estimated based on δ¹⁸O values for seawater and its counterpart in aragonite.
 
Results and discussion
Grain size, was very variable from sand to clay. N1 core consists of 39 sandy silt facies, 28 silty facies, 9 silty sand facies, 9 facies of gravelly sandy mud , 3 facies gravelly muddy sand and 1 facies gravelly sand. The maximum and minimum ​​of sand were abstained at 617 and 690 cm (80.27% and 0%), respectively, while the highest content of silt and clay were at depth 138 and 416 cm (99.45% and 8.95%), respectively. The lowest amount of silt content was observed at 626 cm (7.23%). The average of sand, silt and clay in this core was 25.13%, 72.52% and 1.56%, respectively.
Result of magnetic susceptibility showed a close relationship between particle size distribution and MS magnitude due to variation in terrestrial influx, which is caused by sea-level fluctuations in different times. This process increases with particle size and ranges of MS simultaneously with sea level fall and decreases during sea-level rise.
The range of oxygen (δ18O) and carbon isotope (δ13C) was between -4.22 to -1.17‰ and 2.66 to‌‏ -0.94‰ with a mean of 3.34 and -2.11 ‰ correspondingly. According to the results of carbon dating (14C Dating), age of sediment in the N1 achieved 22070 cal. The rate of sedimentation in the cores varied from 0.57 to 3 mm. Reconstruction of paleotemperature with stable isotopes showed that the maximum temperature recorded in the core was acquired at 144 and 686 cm (27.4 and 27.1°C) and the minimum temperature was 450 cm (13.7°C). The mean temperature in this core was 22.2°C.
 
Conclusion
1-Caspian sea sediments as one of the best region in the world ,record Quaternary climate change in northern IRAN.
2- Accordingly, seven warm and cold periods were identified, which the coldest period being the last glacial maximum (Wurm) with a temperature of 13.7 °C. Furthermore, the highest temperatures related to the pre-glacial and the present periods (about 27°C). Moreover the sedimentology and magnetic susceptibility data confirmed the above results.
 
3-The degree of magnetic susceptibility in different core subsamples indicates environment conditions and low sediment rate.
4 - The rate of sedimentation in the cores varied from 0.57 to 3 mm.
5 - Reconstruction of paleotemperature with stable isotopes showed that the maximum temperature recorded in the core was acquired at 144 and 686 cm (27.4 and 27.1°C) and the minimum temperature was 450 cm (13.7°C). The mean temperature in this core was 22.2°C.
6 - Based on the results of 14C age and stable isotopes 15 centigrade changes in temperature have occurred during about 22,000 years.

Abstract 1-Introduction
The location of shorelines and the state of their changes in the past, present and over time are important for scientists, engineers and managers. For example, analyzing shoreline information for coastal protection design, policy development, updating and reviewing numerical models, assessing sea level rise, developing risk areas for coastal development, achieving the definition of legal property boundary, research and Coastal monitoring is essential. In this article, first the rate of progress and regression of the coastline of southern Khuzestan during the years 1990 to 2020 is examined and then the issue of which part of the coastline of Khuzestan has the most variability is discussed. In this regard, the research hypotheses of variability above the coastline of southern Khuzestan due to the presence of sand masses and most variability of the western parts of the coast of Khuzestan due to the composition of sand masses is the management of coastal areas and implementation Engineering projects in these areas require information such as the current location of the shoreline, its location in the past, and forecasting its location in the future.
 
2-Materials and methods
 Khuzestan province, with 927 km of land border and 975 km of water border, has 136 and 632% of the total land and water borders of the country, respectively (Report of the Geological Survey of Iran, 2016). These figures are equivalent to 635% of the total land and water borders of the country and Khuzestan province is in the sixth place among the border provinces of the country in this regard. The tools used in this study include 1: 50,000 topographic maps, 1: 100,000 geological maps to study the topographic and geological status of the area, the most important of which are Arc GIS, ENVI, IDRISI, SPSS. In this research, achieving the intended goals has been done in several stages, which are described in the following steps. The first stage includes gathering the desired information about the region as well as theoretical foundations on the subject under study. The second stage includes collecting information and layers needed to study the natural state of Khuzestan province. In the third stage, in order to prepare land use maps, Landsat satellite images have been downloaded from the relevant site. After preparing the images, the necessary pre-processing has been done on the images, and finally the land use maps of the area related to the years 1990, 2000, 2010 and 2020 have been prepared. Finally, after preparing land use maps, using the LCM model, the changes made have been studied and analyzed, and using it, the trend of shoreline changes during the study periods has been evaluated.
 
3-Results and discussion
In this study, in order to evaluate the changes in the coastline of the south of Khuzestan province, multi-time satellite images were used. The study of land cover during different periods indicates that the coastlines of Khuzestan province are associated with high variability. In fact, due to the fact that a large part of the coasts of Khuzestan province is covered by low-slope and low-altitude sand strips, these coasts have a high potential for erosion and are affected by the retreat and advance of the sea. The study of the coastline in the study area indicates that the coastline of the south of Khuzestan province is facing a lot of fluctuations and during different periods under the influence of hydro-climatic factors, erosion and sedimentation, has been faced with many changes so that during the year Between 1990 and 2000, much of the coastal sand strip was submerged and actually turned into a blue zone. Most of the changes made during this period were on the southern coast of Bandar emam Khomeini. Between 2000 and 2010, sand strips advanced into the sea and shrinked due to sea retreat and sedimentation. Between 2010 and 2000, it was again faced with the advance of the sea and the increase of the water area, which, like the previous periods, had the most changes in the southern shores of Imam Khomeini port.
 
4- Conclusion
In this study, according to the objectives, the changes of coastlines in the southern coasts of Khuzestan province have been investigated using Landsat satellite images. In this study, first the land cover map related to the years 1990, 2000, 2010 and 2020 was prepared and then the temporal and spatial analysis of changes was performed and then the trend of changes in the coastlines of the study area was evaluated. The results of the evaluation of shoreline changes during the years 1990 to 2020 also indicate that in this 30-year period, due to the fact that the shorelines of the study area are mainly composed of sand strips, it faces many fluctuations and changes. According to the results, during the years 1990 to 2020, about 707 square kilometers of land in the study area has been converted into a water zone, which is mainly related to the erosion of sand belts as well as the advance of the sea. In addition, during this period, 1.6 square kilometers of vegetation and 1.1 square kilometers of man-made areas have been converted into water. Also, the results of the assessment of land cover changes during the years 1990 to 2020 indicate that during this period, about 14.5 square kilometers of water has been converted to land. According to the results, the amount of about 12.3 square kilometers was related to the conversion of water zone to sand zone, the main reason for which is sedimentation and movement of sand masses towards the iodine water zone.

Abstract Introduction

Instrumental records span only a tiny fraction (<10⁷) of the Earth’s climatic history. Therefore, indirect source of climate data must be used. Subfossil pollen and plant macrofossil data derived from sediment profiles can provide quantitative information on past climate. Recognizing the relationship between pollen assemblages and climatic variables and then interpreting fossil pollens base on relationships between them is required to quantitative reconstructions in different regions. Despite pollen-based quantitative reconstruction has begun several decades ago; studies on Iran's past climate have been mainly qualitative and comparative. In this study we used a modern pollen dataset consisting of 119 modern surface samples along significant ecological and climatic gradients over the Zagros Mountains and west of Iran to develop transfer functions and quantitative reconstruction of climatic variables.
 

Materials and methods

In this study collected 59 samples, also 60 samples were collected by wright (1967) were used. Five subsamples of 15*15 cm² within an area of 100 m² were mixed into on sample at each site. Their geographic locations and altitude were determined using GPS. The altitude gradient of these samples is 150 to 4130 m ASL where mean annual temperature ranges from 25.94 to 2.1 C and mean annual precipitation ranges from 203 to 748 mm. Samples were prepared using combination standard techniques of Fægri and Iversen (1975) and Erdtman (1951). A Hund WETZLAR microscope at a magnification of 400 was used for pollens identification and counting. 300 pollen grains were counted for each sample.
A total of 58 pollen taxa were recognized from the surface samples of the 119 study sites. Modern climatic data of 195 meteorological stations of western Iran were used for spatial interpolation. Eight environmental variables were chosen: altitude, mean annual precipitation, mean annual temperature, mean summer temperature, mean winter temperature, mean winter precipitation, mean summer precipitation, mean spring precipitation. Modern Analog Technique (MAT) method was used to reconstruct climatic variables in this study. The MAT is a calibration method for reconstructing a past environmental variable (e.g. temperature) from faunal assosications. It works by finding modern sites with faunal associations close to those in fossil samples. Environmental data from the modern sites are then used to estimate the environment fossil. In order to remove the effects of high collinearity among environmental variables in the process of analyses, we examined the Variance Inflation Factors (VIFs) for each environmental variable. If the VIF value of a variable was larger than 10, the variable was assumed to be almost perfectly correlated with the other variables and it captures little variance. A sediment core that used in this study, (63-J) of Zaribar lake with 25 meters long from the western shore of the lake, were taken by Wright in 1963 and pollinated and published. All radiocarbon dates obtained from Lake Zaribar sediments and published by authors show that this core covers 22500 years before present.
 

Results and discussion

Transfer functions, based on Modern analog technic (MAT), were developed for mean annual temperature (R²=0.6, RMSEP=3.74), mean annual precipitation (R²=0.79, RMSEP=82.74 mm) and mean precipitation of spring season (R²=0.62, RMSEP=21.1 mm). Our results confirm that pollens assemblages can provide reliable estimates of the climatic parameters. The results of quantitative reconstructions of the temperature of the last glaciation of the Earth showed that the air temperature in western Iran was on average 4 to 5 degrees lower than the current period. Also, the mean annual precipitation has been on average 20% less than the current period. At the beginning of the Holocene, the temperature rises significantly, so that the temperature was 1 to 2 degrees higher than the current period. In the Middle Holocene, the temperature dropped by about two degrees, and this situation with low fluctuations has remained almost constant until today. Prediction errors of pollen-climate transfer functions that were calculated in this study is MAP_RMSEP=82.7 mm, ca. 15.1% of the MAP range; MAT_RMSEP=3.74 C, ca. 15.5% of MAT range. A number of factors can influence the prediction error of the calibration dataset such as topographical variation that affected temperature and precipitation variations. Moreover, human impact on vegetation may be another important factor that complicates many pollen-based climate reconstructions. It is important to note that the small number of samples also increased the amount of prediction error.
 

Conclusion

For pollen base quantitative reconstruction in different regions, a reliable number of samples should be collected in different regions, especially drier or wetter regions, as well as colder or warmer regions. Among the climatic variables, the mean annual precipitation has a more significant relationship with the pollen assemblages of the samples and has a better ability for quantitative reconstruction than other variables. Researchs in the Middle and South Zagros shows that during the last glacial period, the vegetation type characterized by high values of chenopodium and Artemisia. This type of vegetation indicates the prevalence of cold and dry weather conditions in this area. The results of quantitative reconstruction of this study showed that in the last glacial period, the air temperature in this region was 4 to 5 degrees colder and the amount of precipitation was 20% less than the current period.

Abstract Introduction
Calcareous soils are widely distributed in arid and semi-arid regions of the world and the presence of carbonates in the soils affects both physicochemical properties and the pedogenic evolution. In addition, soil carbon plays a critical role in the global carbon cycle, and pedogenic carbonates are an important sink for atmospheric carbon. Pedogenic carbonates are also the proxy of past climatic variations which are frequently used in geomorphological and paleoclimatological studies. The aim of this paper was to provide a comprehensive review for formation and accumulation of the pedogenic carbonates in arid and semi-arid regions.
 
Methodology
We reviewed the published studies on carbonates formation and accumulation in the soils. Dynamic and processes of carbonate accumulation were explained. Accordin to the literatures, 15 conceptual modeles and 15 numerical and computer modeles of pedogenic carbonares formation were identified.
    
Results
Numerous models and classification systems have been proposed for the formation and evolution of pedogenic carbonates, including conceptual models and numerical and computer models. Indeed, conceptual models are qualitative descriptions of events and changes in the systems, while numerical models are quantitative descriptions of events and processes and can be very challenging due to the very complex nature of the soil system.
Generally, conceptual models of calcrete development can be divided into two categories of conceptual models without considering landscape processes (pedon scale models) and conceptual models with considering landscape processes (landscape scale models). At the pedon scale, three types of conceptual models have been defined for the development of calcic horizons: (1) the model of progressive changes, (2) the model of in-situ alteration and (3) the rhizogenic model. On the other hand, five conceptual models have been proposed for the evolution of calcareous soils with considering the processes of erosion, sedimentation and degradation of calcretes.
Numerical and computer models of carbonate accumulation in soils can be used to study the influences of late Quaternary climatic changes on the carbonate accumulation in soils. In general, mathematical, compartment and hydrological models have applied in the modeling of calcite accumulation in soils. However, although theses models may be internally correct, they may represent incomplete phenomena due to the lack of enough knowledge of the system or incorrect assumptions.
 
Discussion
In the conceptual models, the process of carbonate formation is considered as crystallization of calcite from soil solution, calcification of plant tissue or recrystallization of calcite crystals in the parent rock. Because conceptual models study the evolution of carbonates over time, chronosequences (e.g. the geomorphic surfaces of alluvial fans) have been used as a tool in the development of these models. Overall, despite the widespread application of conceptual models at the pedon scale by geoscientists, there are some disadvantages:
 
(1) Many of these models do not consider the role of landscape processes such as erosion and sedimentation in the process of carbonate accumulation.
(2) Conceptual models assume the development calcic horizons as evolution from one stage to another in the range of 4 to 8 major evolutionary stages with a linear trend. However, micromorphic analyses have been demonstrated the polygenetic and nonlinear nature of mature calcretes.
(3) Many conceptual models have assumptions that may not be appropriate for many parts of the world. Some models consider the presence of interbedded limestone, the presence of clayey sediments or the presence of a natric horizon in the early stages of development. Therefore, these models may have only regional implications.
(4) In some models, different formation mechanisms are suggested for similar phenomena. For example the evolution of a laminar layer on the surface of mature calcretes are attributed to the accumulation of moisture and plants roots or the accumulation of aeolian silt by lichens.
(5) Recent studies and the application of micromorphological techniques have shown that conceptual models are over simplifications and do not take into account many processes.
Despite the issues of conceptual models, these models are still valid and are widely used to describe the morphology of pedogenic carbonates due to their simplicity of application and high efficiency.
Computer models have been developed since the early and mid-1980s and have been used primarily to study the effect of Quaternary climatic indicators on the accumulation of carbonates in the soil. Initially, models were developed with an emphasis on physical and chemical processes of calcite deposition in soils and soil system was considered only in the CaCO₃-H₂O-CO₂ system without considering the role of biochemical reactions. Recently, biological factors and the effect of plant roots as well as weathering of aluminosilicates on calcite formation have also been considered.
In addition, the assumptions of these modeles to simplify calculations which have a great impact on the results:
(1) Rainfall infiltrates into the soil fully and in one dimension and there is no horizontal flow or surface runoff.
(2) Soil temperature is assumed to be constant and seasonal variations are not considered. In addition, the use of modern temperature as a long-term variable is incorrect due to Quaternary climatic changes.
(3) Water movement through the pedon is assumed as a saturated flow and unsaturated flow, which is important in coarse textured and dry soils, is ignored. In addition, the effects of matric potential changes and upward movement of water in the soil by plant roots, are not considered.
(4) Changes in the amount of hydraulic conductivity and soil water holding capacity during the accumulation of carbonates in soils are of important. For example, plugging the soil matrix with carbonates increases the water holding capacity of soils. Furthermore, the formation of carbonate nodules causes changes in the physical properties of the soil, as well as changes in the path and velocity of water in the soil and may result in the preferential dissolution of calcite.
(5) In many numerical models, carbonate transport is assumed to be a mass flow and the diffusion of carbonates in the soil is ignored.
(6) The origin of calcium ions in many models is considered as a constant rate of dust input and/or a constant concentration of calcium ions in rainwater, which is not reasonable in the long-term due to late Quaternary climate shifts.
(7) The amount of present rainfall in many models is considered as long term precipitation, which is not a correct assumption owing to climatic change in the Quaternary. In addition, the models are not able to estimate the effects of rainstorms on the formation of carbonates in arid regions. Studies have shown that heavy rainfalls in arid lands can be very effective in formation of calcic horizons.
(8) Information on the partial pressure of carbon dioxide in soils is in many cases inaccurate and also the average annual application of this index is not correct due to seasonal fluctuations and ecological changes during the Quaternary.
(9) Many models consider only calcite mineral as soil carbonate mineral and ignore other minerals, especially dolomite. Studies have proven that the secondary calcite that precipitates from the soil solution is richer in magnesium than pure calcite. The mineralogical analysis of pedogenic carbonates of soils demonstrated the occurrence of low-Mg calcite.
(10) Numerical models assume that the processes of dissolution and deposition of calcite occur instantaneously and very rapid relative to water movement in soil, which may not be a correct assumption in all soils.
(11) Many models do not consider the role of erosion and sedimentation processes in carbonate accumulation and assume that soil thickness is constant during the evolution.
 
Conclusion
Despite the problems of both conceptual numerical models, they are very valuable tools for testing past climatic scenarios on soil development.
Finally, a review of conceptual models shows that these models are mainly based on the soils of the arid regions of the southwestern United States, the Mediterranean, and Australia. Although calcareous soils cover most of Iranian lands, there is no modeling for carbonate accumulation processes in these soils. Therefore, there is a very strong potential to test the above models and provide new conceptual models based on the conditions of Iranian soils.

Abstract Introduction
The study of lake sediments has been widely used in recent decades to identify past climate and environmental changes. Lake basins have significant spatial and temporal patterns and provide valuable evidences of physical and chemical changes. However, in general, the climate of the Holocene period has been more stable and uniform than previous glacial and interglacial periods. However, there have been many sudden climate events that have affected the lifestyles and activities of human groups. In this study, using the results of geological, climatological and archaeological studies, climate change and the environment of the Central Zagros from the Late Pleistocene to the present have been studied and reconstructed.
Methods
In this research, multi-proxy method has been used. The results of geochemical analyzes, magnetic susceptibility, chronology and palynology of sedimentary cores has taken from Hashilan wetland in Kermanshah were studied and analyzed.
Results
The results of the analysis showed that most of the identified Holocene climatic events in the world have also occurred in Central Zagros. In the last period of glaciation, the climatic conditions of this region were cold and dry with the predominance of physical erosion and the dominant vegetation of the region was steppe and Chenopodiceae. Before the onset of Younger Dryas event, there was a warm and humid period in the region that coincided with the hot and humid period of Boling Allerod in Europe. After the end of Younger Dryas cold event, the Early Holocene period began 11,000 years ago in the region. The Early Holocene's humidity in the Central Zagros region was not enough to grow Quercus trees, and compared to Jordan and Turkey, the climate was drier. Due to changes in insolation (the amount of radiation received by the sun within 60 degrees north: (Milankovic cycle) and its increase in the northern hemisphere, the amount of radiation received by the northern hemisphere increased in the summer, which led to the expansion of Inter Tropical Convergence zone belts and Subtropical high pressures and the summer monsoons of the Indian Ocean zones became wider. In the Late Holocaust, the Zagros region was dominated by STHPs and received very little spring and summer rainfall due to the influx of high-pressure tropics. As the insolation reducing in the middle Holocene and the STHPs retreat to lower latitudes, the humidity entry from Atlantic Ocean and Mediterranean into the region increased, and quercus trees grew in the area during the wet period of 7,500 years ago. In Late Holocene, the intensity of dry climatic events has increased so much that the driest period was 3,200 years ago.

Abstract Introduction
 
One of the processes of the Quaternary era is the glacial and interglacial periods. In the glacial period, loesses deposited and in the interglacial period, Paleosoils were formed. The northern part of Iran is geographically the same as countries such as China, a large part of which has been covered with loess sediments during the Pleistocene glacial period. Loess sediments in northern Iran reflect several cycles of climate changes and the evolution of the earth's appearance for the middle to late Quaternary period. In this region, the Loes-Paleosoil sequences are one of the most important terrestrial archives of climate change and provide a bridge between Southeast European and Central Asian loess sediments. To reconstruct paleoclimate changes, magnetic susceptibility is used as a climate proxy. The high magnitude of the magnetic susceptibility indicates the large volume of magnetic minerals. Chemical weathering causes the formation of magnetic minerals such as magnetite and maghemitite. These minerals are abundant in Paleosoils and can be determined by analyzing the magnetic susceptibility of Loess and Paleosoils. The magnetic properties of the Loess-Paleosoil sequence are considered to be evidence of paleo precipitation and weathering.
Study area
Geographical location of Saadabad sedimentary section in the northern region is 36° 49' N and 54° 22' E, at an altitude of 140 m a.s.l. Saadabad sedimentary section is located in the construction zone of Alborz and in terms of the main sedimentary-structural zones of Iran is part of the southern Caspian coast. This zone includes areas, which are located in the north of Alborz fault and block the Caspian Sea coast on the coast of Iran and are covered to the east with thick layers of loess.
Methods
In the field work that was carried out in May 2017, after determining the exact location of the sedimentary section, sampling was performed. Before sampling, aerated sedimentary layers are dug up and removed to reveal fresh deposits. Then, using the meter, the layers were divided into 10 cm intervals. 92 samples were prepared at 10 cm intervals from the sequence. Measurement of natural residue magnetic (NRM), by the model rotating magnetometer (JR-6A), and measurement of magnetic susceptibility by magnetic intensity measuring device, in the magnetometry laboratory of the Geological Survey of Iran.
Results
Table 1 shows the measured values of the magnetic parameters. Due to the length of the table, only a few examples are given in the table.
Since high magnetic susceptibility can indicate a greater concentration of magnetic minerals in the sample, it can be concluded that the paleosils of the sequence studied have more magnetic materials than the loesses, which are inside the soils. They can be the result of podogenesis processes. Because rising temperatures and humidity cause soil erosion processes and increase oxidation and thus increase the amount of magnetic materials, it can be concluded that in paleosoils with higher magnetic susceptibility, warm and humid climates dominate in the environment. Micromorphological studies of directional clay layers, Fe-Mn hydroxide, show that the palaeosoil of section 5 is moderate to well developed. As the climate changes to higher temperatures and higher humidity, weathering and pedogenesis also increase, leading to the development of a pedogenic oxidation environment as a result this produce the formation of tiny magnetic grains such as maghemite and magnetite in this oxidizer environment and thus increases the magnetic susceptibility. In Saadabad, the high amount of xlf along with the high percentage of xfd suggests that many of the ultra-fine maghemite and magentite grains may have been formed during pedogenesis under a long, humid, warm climate. The findings show that the different behaviors of magnetic susceptibility between the loess of the drier and wetter areas are mainly caused by their different pathogenic environments, which in turn are related to local topography and climatic conditions.
Conclusions
High levels of xlf and xfd indicate high precipitation during the formation of Paleosoils. Post-sedimentation processes may increase the amount of MS by producing new ferromagnetic minerals during the oxidation of wheathered soils, and may also reduce the amount of MS by reducing the processes. The clay material in which the soil is made is the main factor influencing the change in magnetic mineralogy and magnetic susceptibility. This study also shows that magnetic susceptibility is a complex parameter and its use as a precipitation control has certain limitations and conditions, and when the magnetic properties of the loesses are used for paleo climate reconstruction, more attention should be paid to topography, environment. Sediment and weather factors.

Abstract Introduction
Research on ancient and recent global environmental change has mainly been based on natural records, such as those preserved in ice cores, loess deposits, tree rings, corals, stalagmites, and deep-sea and lake sediments (Li et al, 2014). These records have been used to reconstruct the Earth’s past climate, environment, and ecological history (Zhou, 2006). However, in the arid and semi-arid desert regions that are an important part of Earth’s system, the difficulty in finding highresolution natural records has made research on environmental changes in these regions lag behind research in other areas (Xia, 2005). Nebkhas are fixed aeolian landform which are formed around Shrubs and trees in dry and semiarid areas as a result of the aggregation of aeolian sediments (Cooke et al, 1993). The unique developmental and depositional characteristics of nebkhas make them ideal carriers of proxies that can be used to study late-Holocene regional aeolian activity, the alternation between dry and wet conditions, hydrological characteristics, the ecological environment, and their evolution in arid and semi-arid desert regions (Wang et al, 2004; Hesp and Mclachlan, 2000; Wolf et al, 2000 )
 
Materials and methods
In the first step, according to satellite google earth images and field observations an area with a dimension of 400 * 400 meters was specified. In the next step, the existing Nebkhas near the specified area whose vegetation was at least covering between 85 to 95 percent of the deposits were numbered. Then, through MATLAB and Random order, four Nebkhas were randomly selected. In the following stage morphometric parameters such as the height, width, Length, and the height of the Shrubs was measured. Afterwards, using field instruments, the nebkha selected for intensive analysis was excavated from its crest to its base, and sediments were sampled at 5-cm intervals throughout the profile. Overall, 79 samples from 4 Nebkhas were taken and transferred to the geomorphology laboratory for the purpose of determining organic matter and geain size of the sediments. To determine the grain size of the sediments hydrometric and granulometric methods were employed. The geain size results were analyzed in GRADISTAT4.0 and RockWorks software with Folk (1954) method. The measurement of organic matter in this study was done according to loss on ignition (LOI) method when the samples were heated at 550 °C for 2 h (Qiang et al, 2013).
 
Results and discussion
The results of analyzing the organic matter of the Nebkhas’ sediments show that despite the fact the content of the organic matter during the formation of Nebkhas showed a significant change, the content of the organic matter of lower layers’ Nebkhas was higher compared to other layers, indicating a drier environmental condition after the formation of Nebkhas. The findings of the geain size of sediments show that although the threshold speed of past winds had some fluctuations in the studied area, in the upper layers of all Nebkahs a significant aggregation of higher than 250 micron sediments was observed. The findings obtained from the fluctuations of the relative speed of wind threshold based on the diameter of sediment particles in the studied area demonstrated that the size of different particles in the layers of Nebkhas of the studied area show the fluctuation of wind energy when the Nebkhas were formed.
 
Conclusion
The results of organic matter showed that in the initial stages of the formation of Nebkhas, the studied area had a suitable condition regarding the amount of water for the growth  Shrubs which cover Nebkhas but in the course of time the aridity level of the area increased. Moreover, the findings of geain size of the sediments suggested that the aggregation particles which were larger than 250 microns in the upper layers of the nebkhas was the result of human activities such as abandoning farm lands and withering of palm trees. As a result, the threshold speed decrease of wind erosion and deflation of larger particles has occurred in the studied area. In sum, the findings showed that the studied Nebkhas are relatively exact proxies which can provide us with significant insights with regard to environmental changes in the area.

Abstract Introduction: Seismicity is closely related to active Quaternary faults.This attracts many researchers to investigate the quantitative relationships between them. As a new parameter, FMP is defined to quantify earthquake risk.Iran is one of the most active areas of the world in terms of tectonic activities in the Alps-Himalayan belt. One of the characteristics of this belt includes the presence of thrust faults and associated folds along with the general trend of the belt - northwest - southeast as well as transverse faults with north, northwest - south southeast trend . Folded - Thrust Zagros as a part of the Alpine - Himalayan orogenic belt and one of the youngest and most active continental collision zones on earth, with a length of about 1500 km extending from the Tarsus Mountains in northeast Turkey to Minab fault in the northeast of Hormoz Island in southern Iran.the earthquake risk in Iran, especially in populated cities, is high and the high risk areas are located near Iran's active faults in terms of earthquake events. earthquake is one of the natural disasters and has been a major threat to human being, over the past history. for this reason, man is always seeking a solution to reduce earthquake risk in earthquake-prone areas. The 180-km-long Glabaf fault system and the NNW-SSE overall Trend comprise several fault-stepped fault sections that have steep slopes (60 to 90 degrees) on both the east and west sides. The Gelbaf fault itself is part of a larger fault system, called the Neyband-Golbaf fault. It is a strike-slip fault system and forms the western margin of the Lut desert. In this paper, The Movement Potential Evaluation of the Active Faults of the Golbaf area is investigated based on the relationship between the geometric properties of the fault and the Regional tectonic stress field region. The parameters examined for the active faults and the ratio of the range of possible movement has been obtained. The results of this method show high compatibility with past seismic records, therefore, this theoretical model is based on the relations between the geometrical properties of faults and the Regional tectonic stress field of dominant dominance, to assess the activity of a seismic fault in terms of different criteria have been proposed. In the empirical investigations, there are various estimates for the longitudinal selection of the part of the fault that the movement recovers for each tectonic seismic zone. The problem with these estimates is the lack of sufficient data available for different states tectonic in Iran. There are also various empirical equations for the relationship between seismic fault length and fault length. One drawback of these empirical equations is the failure to pay attention to the mechanism of the faults, Therefore, the relationship created is for the large region, which will cause an error in seismic power calculation. These points have been applied in some equations, and factors such as cumulative fault accumulation, morph faults geometrical , location tectonic region and seismic features of each area should not be overlooked. In this study, the possibility of faults future movement based on the relationship between the maximum axis of tectonic stress and fault geometry and then the estimation of FMP variable for seismic probability in the surrounding of major and active faults in the studied area was evaluated.
Materials and Methods: How to calculate the maximum calculated stress is that it draws calculation to the seams conjugate harvested and Schmidt network, the maximum stress in the region studied was calculated and after the structural impressions at  18 Section, the equations of this model were used. Using the inversion method, the main maximum stress is calculated as the regional stress in each section and is embedded in the equations.
Research findings: In order to properly analyze the study area, The Movement Potential Evaluation of each active fault was calculated in these sections.
Discussion and Conclusion: According to the Movement Potential Evaluation of the Active Faults  values of Golbaf and Shahdad faults, the Golbaf fault is introduced as a young fault in the study area. Regarding the obtained values, it can be analyzed that, in view of the high epicenters of earthquakes occurring in the northwest and southwest of the area, a tension aggregation in a large area in a perpendicular direction to the north-east-south-east trend of not expecting.

Abstract Extended Abstract:
1-Introduction
There is a direct relationship in evaporative deposit with the changes in the depth of the lake. Therefore?, valuable information is gained regarding the causation of changes in environment over time. Evaporite minerals formation is a natural phenomenon accruing in water-bodies containing deferent mineral Since sulfate is abundant in seawater and saline lakes, it is main component in evaporative minerals (Lewis and Mc Conchie,1994). Playa lake deposits even in small precipitation rates may cause major changes in lake-level, salinity and sedimentary records (Battarbee 1999). The sediments generated in present saline lakes and playas have been studied by numerous researchers in order to determine the paleoclimate (Spencer et al. 1984; Holliday et al. 1996; Crowley and Hook 1996; Li et al. 1996; Enzel and Wells 1997; Menking et al. 1997; Lowenstein et al. 1999; Sinha et al. 2006; Chao et al. 2009).
Playas are found in many parts of the world including Western US (Rosen 1991), Australia (Bowler 1986) and Iran (Krinsley 1970). In Iran, the ancient evaporites are present in sedimentary records of the Tertiary evaporites are found mainly in the Zagros Basin and in the Central Iran (Rahimpour-Bonab and Kalantarzadeh 2005, Rahimpour-Bonab et al. 2007a, b). In addition, Holocene evaporite deposits are widespread in numerous playas and lake/playas in various parts of Iran with different characteristics (e.g., Krinsley 1972; Shahrabi 1995; Farpoor and Krouse 2008; Farpoor et al. 2012). In his pioneering work, Krinsley (1970) studied morphology of surficial features of 60 playas within the interior of Iran. He determined characteristics, distribution, and development of the available playas. According to his findings, because the form and bedrock permeability of most of the Iranian basins have remained essentially stable since the late Pleistocene (Würm), subsequent hydrologic changes can be attributed to climatic changes.
Rahimpour-Bonab and Abdi (2012) with study on the lake/playa Meyghan Flowing water with low percentage of ions and Na–(Ca)–(Mg)–SO4–Cl–(CO3) types evolve, into a brine with high ions concentration during the geochemical evolution and mineral deposition. The geochemical evolution yields a Na–SO4–Cl type brine.
While clastic components (calcite, quartz etc.) show on increasing trend in relation to depth, evaporites abundances show opposite trends. Furthermore, the average grain size of sediments increases with depth indicating higher energy in the past. This study evaluated clastic sediments and evaporite deposits’ changes in the sedimentary core Maharlou lake by using physical and geochemical methods.
 
1-2- Study site (Physical setting)
The hypersaline Lake, Maharlou is located in SW Iran with an area of 24910 km² and 1.5 m depth. The lake lies about 20 km east of Shiraz at 1,455 m above sea level (masl) [Fig. 1]. This lake is fed by direct precipitation and water inflow from surface run-offs, a few seasonal rivers and several karstic springs which compensate for the strong evaporation in a semi-arid climatic context (Dumas et al. 2003). The Maharlou catchment area consist of sedimentary rocks, mainly Precambrian diapiric evaporites associated with Mesozoic and Cenozoic limestone, sandstone, shale and dolomite formations. The formation of this lake goes back to the beginning of the Pleistocene because of its hydrogeological properties, past higher lake level stands and the survival of Pleistocene relict fish species (Krinsley 1970; Dumas et al. 2003).
2-Materials and methods
Lakes are accurate intercontinental ambiences to record past environmental changes. After theorical researches, vibracorer machine took 533cm core sample from the north west of the lake near Kaftarak village. Magnetic susceptibility tool measured the magnetic sensibilities. Sequences identified and analysed after cutting sedimental core. Then, 150 samples with high resolution checked to apply combination method, however only 84 items selected. SEM method and LOI analysing system used for geo-chemistry studies. After particle size analyses, sediments are studied to identify life remains of animal and plant as well as lithologic study by using polarizing and binocular microscopes.
 
3-Results and discussion
Lakes are accurate intercontinental ambiences to record past environmental changes. After theorical researches, vibracorer machine took 533cm core sample from the north west of the lake near Kaftarak village. Magnetic susceptibility tool measured the magnetic sensibilities. Sequences identified and analysed after cutting sedimental core. Then, 150 samples with high resolution checked to apply combination method, however only 84 items selected. SEM method and LOI analysing system used for geo-chemistry studies (Sabokkhiz et all 2015). After particle size analyses, sediments are studied to identify life remains of animal and plant as well as lithologic study by using polarizing and binocular microscopes (Sabokkhiz et al 2014). Finally, the age of the core measured by δ14c ageing technique and calculation methods. The age of the sedimental core bottom is 10813 ±60 years BP that presents the time period before Holocene. Existence of los like and lack of biological matters in 521 cm depth show the dominance of the last part the Younger drays (late Glacial). This event has the horizon of the fine grain sediments without life remains. Therefore younger dryas phase of the lake Maharlou is cold and dry. Early Holocene ages, 10200±60 years BP were cold and dry. There were evaporates with fine grains and without biological matters. Afterwards evaporate and siliciclastic particles increased, calcium carbonates decreased and fluvial environment dominance appeared followed by warm and dry age. Middle Holocene ages, 4000±60 years BP came to light by the activity of the springs when pleasant warm and wet weather controlled lakes. There were some fluctuating dry weather conditions until late Holocene age. A Hiatus and detached surface appeared in 3062±45 years BP that showed water offgoing from the lake along with surface weathering. Late Holocene starts from 2000±45 years BP. First demonstrated dry fluctuations then raining increase and then core surface which indicated drying trend of playa basin.
 
4- Conclusion,
4-1- The age of the sedimental core bottom is 10813 ±60 years BP
4-2- Therefore younger dryas phase of the lake Maharlou is cold and dry.
 Early Holocene ages, 10200±60 years BP were cold and dry weather and fluvial environment dominance appeared followed by warm and dry age.
4-3- Middle Holocene ages, 4000±60 years BP came to light by warm and wet weather controlled lakes. There were some fluctuating dry weather conditions until late Holocene age 3062±45 years BP that showed water offgoing from the lake along with surface weathering.
4-4- Late Holocene starts from 2000±45 years BP. First demonstrated dry fluctuations then raining increase and then core surface which indicated drying trend of playa basin.
4-5- These changes are similar to other studies for different lakes in North-West of Zagros mountains such as Parishan lake, Hashilan wetland, Neuor lake in Alborz mountains in late glacial. Recent researches about the time of the early Holocene on Oroumiyeh lake and north Atlantic sea showed lowering in monsoon currents and increase of extreme dryness in middle east, which have similar conclusions to our research on Maharlou lake.

Abstract Introduction
Paleoclimatics studies can respond the many uncertainties about past climate change; an issue that is being studied seriously in the world but less attention has been paid in Iran. The Late Quaternary can be considered as Holocene. Holocene, which spans over 11,000 years ago; In general, it is considered as a period with relatively warm and stable climatic conditions. However, recent studies have shown that the Holocene climate is relatively unstable and characterized by several short-term climate fluctuations. The present study attempts to investigate the events of the late quaternary climate change in Iran. Hence, by studying various internal and external sources, first major climatic changes were identified at the late quaternary, and then these changes were detected in Iran. Then, based on the results of a case study, the results of the studies were tested.
This research seeks to answer the following questions:
- Is it possible to detect the major events of the Holocene climate change in Iran?
- Is there a difference between the time of occurrence of major Holocene climate changes in Iran and other parts of the world?
- How has moisture changes been in cold and hot periods?
 
Method and Materials
This research consists of two sections. In the first, a review has been conducted. In this section, first, using studies in relation to the late Quaternary climate change in the world, major climatic changes were identified in the Late Quaternary. Then, by studying and reviewing existing theories and resources, including books and articles, it has been attempted to determine the overall framework for climate change in Iran at the Late Quaternary. In the second part, the results of a case study were used to confirm the review studies. This case study includes a core length of 8.5 m, taken from the Parishan lake floor. In this section, two proxies were used to carry out analyzes and identify climate changes of late Quaternary, which include the use of palynology and magnetism susceptibility methods. The magnetism susceptibility technique was used to determine the warm-cold periods and the reconstruction of paleo-vegetation was used to determine wet-dry periods. To calculate the AP/NAP index, samples were taken in 10 cm interval from the sedimentary cores and pollens extracted and identified by the method of Moore et al., 1991 (with slightly change). Samples were also used to measure the magnetism susceptibility by use the Bartington Susceptibility Meter with a 1 cm interval.
 
Results The studies on climate change in this period show a number of significant fluctuations, including four cold events: The Younger Dryas, The 8.2 ka cooling event, The Cold period of Migration time and The Little Ica Age (LIA), and 4 warm events: The climatic optimum, The Roman warm period, The Medieval Warm Period (MWP) and The Modern warming period. In the Parishan Lake, 6 major cold and warm periods in Holocene can be identified, for the four of them, it can be found that there is an approximate correspondence with the temperature changes occurring on the planet, but these courses have been delayed.
Discussion
The results indicate a reverse relationship between the moisture index and the magnetism susceptibility; in fact, during warm periods humidity has increased, and humidity has decreased during cold periods. The rate of moisture index has also decreased with increasing cold intensity; in the Younger Dryas and The 8.2 ka cooling events have lowest temperatures in the region and the lowest moisture index has been recorded in these two periods. The highest moisture content was recorded in The Climatic Optimum.
 
Conclusion
The results of this study showed that there is a good correlation between cold and warm periods in other parts of the world with Iran, although between these periods in Iran and North Europe and the United States there is a time lag of approximately 200 to 300 years. Also, the existence of cold-dry and warm-wet periods was confirmed in the past of Iran. In the studied region, at the Younger Dryas and The 8.2 ka cooling events, with the lowest temperatures in the area, the amount of tree species has reached almost zero, which indicates the dryness of the area during cold periods. In all warm periods, the moisture index of AP/NAP was higher than the cold periods. It can be concluded that warm periods were generally more humid than cold periods.

Abstract Abstract
 Sediments provide a continuous, sensitive record of changing conditions of environment and processes within plain and in the surrounding plain, thus they contain significant archives of past environmental change on the continents. Valuable informations on regional and global scale patterns of past climate
variability in the Azarbayjan region have been documented by numerous paleoclimate studies, but some of these may partly explain the contradictory palaeoclimate histories. Although paleoclimate changes in the eastern Azarbayjan during the late Pleistocene to Holocene are well constrained in terms of proxy-climate data. In this study the data were collected, the sub-bottom profilers. In this study with aim of monitoring of past environmental changing of Tabriz plain, widely used indicators of Quaternary paleoclimates. In particular, the geochemical ”archives” contained in sediments provide long and high-resolution proxies of terrestrial records. However, such geochemical proxies especially those gathered from the holes , can only be indirect indicators of past climates and may be influenced, to different degrees, by several independent factors. In order to overcome this indirectness, multi-proxy methods are widely used. Spt methods ,Granolometry,and textural methods are these used method. Also used Ph analyzing for explain of Quaternary history of Tabriz plain. The result of this study suggested of the Tabriz plain hade very different paleoclimate conditions. The amount of clay and soft grain sediment in depth of ground is high. Our results indicate that the region was relatively cold and wet during the late glacial, and some times were dry. During the beginning of the Holocene, while precipitation values were high, the temperature gradually increased than , the region was warm but extremely dry.
 
1-Introdution
Sediments are sensitive to climatic (global and local)and tectonic, and sedimentological changes,providing clear sedimentary records about them. Shore deposits are generally composed of loose, unconsolidated sediments, ranging from very fine sand up to pebbles and cobbles in terms of sediment size. They receive their sediments from rivers draining a catchment area and the erosion of nearby cliffs and foreshore outcrops. fluvial sediment capacity transported to the coastal area. Shore systems deal with the nteractions between depositional and erosional processes as waves, currents, rivers, tides, and winds). The Tabriz plain undergone significant modification associated with water level changes related to climatic conditions and tectonism since its formation
The East Azarbayjan plain is situated on basement rocks consisting of Mesozoic metamorphic rocks,
Triassic limestones, Upper Cretaceous ophiolites, and Miocene turbidites. These rocks are unconformably overlain by Quaternary volcanics and coeval lacustrine sediments. The basin infilling ends with Late Quaternary travertines and recent unconsolidated fluvial sediments. To restructure the past climate and environmental conditions is crucial in terms of understanding the living conditions of previous communities. On the other hand, the accurate interpretation of human impact on past environmental conditions is very important in terms of fully understanding the dimensions of man's pressure on nature and the changes in land use. Human impact emerges as an important and constant factor that regulates the vegetation dynamics in the lands occupied especially in the Late Holocene. In general, the climatic changes experienced in the Eastern Azarbayjan region and Tabriz plain are consistent with the hole layer data. This is impoErtant in terms of reflecting effects of global
climatic changes in the study area.
 
2-Materials and methods.
To restructure the past climate and environmental conditions in the Eastern Ayjan region in the Late Pleistocene and Holocene investigated by grianology analysis. In this study ,used of Geocronology data ,sediment layer and pedology property for experting of environmental changes in Tabriz plain. In field study is measured and is analysed grain of sediment in laboratory. Also used spt method for investigation on soft grains in sediment. Investigation on PH of sediment and deposits were other methods for understanding of past environment condition.
 
3-Results and discussion
Extensive paleoclimatic studies have provided evidence that the Holocene is characterized by wet and dry climatic fluctuations and rapid shifts worldwide. We propose that, the sedimentary record of Tabriz plain
provides a suitable geological archive for understanding the changes in this climate sensitive coastal area. The work reported here is predominantly focused on lithological observations, inorganic parameters and basic organic matter characteristics. The field work were collected from of the sediment cores. The latter technique has been used to obtain geochemical profiles, which are interpreted to identify local climate signals, distinguish internal and external effects on the environment such as physical dynamics, chemical
characteristics of the soil column. This study also aims to analyse the effect of main global climate trends on the environment of plain such as the Early Holocene humid phase, the Middle Holocene dry conditions and various Late Holocene events including organic matter rich sedimentation. Investigation on sediment layer show that from 15 to 35 meter is formed by clay ,sandy –silt and silt. This composition is suggested of low energy in past environment. Changes of sediment property is show that climate changed. Investigation on soil sampels and analysied by spt method show that most of grains is soft in deep of layers. In between of layer can see wind sands. Percent of Clay grain is decrease in eastern part of plain.
 
4-Conclusion ,Keywords
The study of distribution of soft grain materials in Tabriz plain show that most part of area in 20 meter of deep is formed by soft grains. 50 percent of this soft grains are clay and silt. Northern part of plain is formed by red soils that sources of his soil is Quaternary sediment. Thick layer of clay suggested of dry condition continued length time . Yellow soil is evidence of cold and dry condition in Tabriz plain. Old landslides in between layer show that in plain wet condition some time were governed. Especially the signal of the Early Holocene humidity is documented in sedimentary record. Such investigations which are now in progress will provide further insight into climate-induced changes in the sediment.
Thick of wind sand layer suggested that the warm period is governed 400 year in plain. This period marked by color layer in around of Tabriz.