نوع مقاله : مقاله پژوهشی

نویسنده

گروه جغرافیا، دانشگاه زنجان، زنجان، ایران

چکیده

آنتروپوژئومورفولوژی، شاخه تقریباً جدیدی از علم ژئومورفولوژی است که به بررسی نقش انسان در تغییر چهره­ لندفرم­ها و اصلاح عملکرد فرایندهای ژئومورفولوژیکی مانند هوازدگی، فرسایش، حمل و نهشته­گذاری می­پردازد. افزایش میزان فرسایش خاک در نتیجه تغییر کاربری اراضی، نمونه­ایی از تاثیرات غیر مستقیم انسان بر فرایندها و لندفرم­ها است. با­توجه به اینکه نرخ رشد جمعیت، شاخص مناسبی برای ارزیابی کیفی و کمی فرایندهای متاثر از عملکرد انسان، نخواهد بود، معادله­ پتانسیل آنتروپوژئومورفولوژیکی معرفی شده که دو عنصر اساسی آن درجه­ توسعه­یافتگی(میزان دخالت در محیط) و میزان­ درک و آگاهی مردم) فرسایش ناشی از­ عملکرد انسان) است. بر این اساس، هرچه درجه توسعه یافتگی و میزان آگاهی­های زیست­محیطی مردم کمتر باشد، پتانسیل فرسایش ناشی از عملکرد انسان، افزایش خواهد یافت. برای ارزیابی پتانسیل آنتروپوژئومورفولوژیکی با استفاده از روش نیر، 31 کشور از قاره­های متفاوت انتخاب و مورد بررسی قرار گرفت و شاخص آن­ها بین 0-1، محاسبه شد. بر­اساس نتایج به دست آمده، کشورها در سه گروه با پتانسیل آنتروپوژئومورفولوژیکی کم(I<0.30)، متوسط (0.30 ≤ ≤ 0.49) و زیاد(≥ 0.50) تقسیم­بندی شدند. کشورهای مجارستان، ایران و شیلی به ­ترتیب در گروه پتانسیل آنتروپوژئومورفولوژیکی کم، متوسط و زیاد، قرار می­گیرند. بر همین اساس، اقدامات مقتضی مدیریتی و مهندسی باید انجام شود.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Antropogeomorphology: The Role of Human in Modifying the Face of the Earth

نویسنده [English]

  • Reza Khoshraftar

Department of Geography, Zanjan University, Zanjan, Iran

چکیده [English]

Antropogeomorphology is a new branch of geomorphology which investigates the role of human in changing landforms and the process of geomorphologic modification such as weathering, transport and deposition. Management and engineering related activities result in widespread changes in landscapes. Some landscapes such as terraces in arable lands, which are formed in farmlands and have completely different shapes, are the direct result of anthropogenic processes. Landforms produced by indirect anthropogenic process are not easily recognizable unless they are involved in the formation of natural processes. Such landforms are the result of environmental changes, which are brought about by human activities. One of the examples of such activities is the escalation in the rate of soil erosion due to over exploitation from forests. The main works done in this area include: Man and Nature(physical geography as modified by human action) by Marsh(1864), Man as a Geological Agent(1922), by Sherlock, The Human Impact(1981) by Goudie and Man as a Geological Agent by Nir(1983). Based on many studies about antropogeomorphology, the main fields are: mining, agriculture, settlements, water management, traffic, tourism, sports and industrial impacts on landforms.  
 
Material and Methods
The methods used in antropogeomorphology include: historical, socioeconomic and geomorphological approaches. In this paper socioeconomic behavior, Degree of Development (DD) and Degree of Perception (DP) on rate of geomorphological process investigated. On this basis, in Index of Potential Anthropic Geomorphology (I), the percentage of urban population and percentage of illiteracies indicates degree of development and perception of people resp. The required data can be obtained from international statistical yearbooks. To calculate of effects of climate and topography, the constants Kc and Kr are used. Values of these constants may range from 0.4 to 0.8, (climate) and from 0.2 to 0.8, (topography). (Table 2). According to equation 3, I index 31 selected countries calculated and presented in table 3.Then, I index of selected countries divided into three groups. The final map (fig 5) was drowning on this basis and finally analyzed. Easy of access to data is one of the benefits of Nir method.
 
Results and Discussions
Considering the fact that the rate of population growth is not a suitable factor in quantitative and qualitative assessments of human activities; therefore, antropo-geomorphologic potential equation (eq, 3) is introduced. Two important factors such as the degree of development (rate of human interface in environment) and human perception (human induced erosion) form this equation. Based on this formula, there is a direct relationship between the degree of development and environmental perception on the one hand and the rate of erosion on the other. For assessing the potentiality of antropogeomorphology, 31 countries from different continents were analyzed. The I index have a values between 0-1(Table 3).
 
Conclusions
Based on Nir (1983), classification of Index of Potential Anthropic Geomorphology (I), the results of calculations are presented in table 3. The potentiality of antropogeomorphology in developed and poor countries are different. Moreover, these calculations indicate in three interval times. In some countries for example Iran, Turkey, India and Greece, trend of I index were regressive.
- In countries such as Hungary, Thailand and Poland, I<0.30, the risk of human geomorphologic activities is low.
- In some countries for example USA, South Korea, Philippines, Bulgaria, United Kingdom and Iran, 0.30 ≤ I ≤ 0.49, the risk is not negligible and some management activities should be taken.
- Countries such as Algeria, Morocco, Chile and Nepal  have the highest I index, (I ≥ 0.50), considerable damage followed by antropogeomorphological process. Engineering appropriate and immediate should be taken in these countries.

کلیدواژه‌ها [English]

  • Antropogeomorphology
  • Degree of Development
  • Soil erosion
  • Degree of Perception