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تعیین آسیب‌پذیری بوم‌شناختی مجموعة حفاظت‌شدة توران با ترکیب روش‌های ماتریس آثار متقابل، فرایند تحلیل سلسله مراتبی و فرایند تحلیل توسعه‌ای | ||
| محیط شناسی | ||
| مقاله 4، دوره 39، شماره 4، اسفند 1392، صفحه 45-54 اصل مقاله (666.47 K) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22059/jes.2014.36461 | ||
| نویسندگان | ||
| شهرزاد فریادی1؛ حسین سپهر* 2؛ مجید رمضانی3 | ||
| 1دانشیار دانشکدة محیط‌زیست دانشگاه تهران | ||
| 2کارشناس ارشد رشتة برنامه‌ریزی، مدیریت و آموزش | ||
| 3دانشجوی دکتری رشتۀ برنامه‌ریزی، مدیریت و آموزش محیط‌زیست | ||
| چکیده | ||
| آسیب‌پذیری بوم‌شناسی اصطلاحی عمومی است که می‌تواند در سطوح سلسله مراتبی مختلفی (جانداران، جمعیت، اجتماع، اکوسیستم و سیمای سرزمین) به کار رود. ارزیابی آسیب‌پذیری بوم‌شناختی در علوم محیطی از جمله در ارزیابی آثار و ریسک و پایش محیط‌زیست کاربردهای فراوانی دارد و از این لحاظ حائز اهمیت است. همچنین، آسیب‌پذیری بوم‌شناختی می‌تواند به‌منزلة شاخصی برای ارزیابی کیفیت محیط‌زیست در نظر گرفته شود. ابتدا ماتریس آثار متقابل به منظور تحلیل سیستم ادراکی محیط‌زیست تشکیل شد. سپس، از طریق مقایسۀ درجۀ اهمیت عوامل اکولوژیکی با هم، جدول مربوط به فرایند تحلیل سلسله مراتبی لایه‌های عوامل اکولوژیکی برای تعیین ارجحیت لایه‌ها نسبت به هم تشکیل شد. بر اساس روش تحلیل توسعه‌ای نیز فرایند تحلیل سلسله مراتبی فازی برای وزن‌دهی به طبقات هر یک از لایه‌ها انجام گرفت. مهم‌ترین عاملی که در میزان آسیب‌پذیری اکولوژیک منطقه با استفاده از ماتریس اثر متقابل و روش AHP به دست آمد، فرسایش‌پذیری سنگ مادر بود که روی عوامل دیگر همچون عمق خاک، فرسایش بادی و آبی و عواملی از این قبیل، تأثیر بسزایی دارد. پس از استنتاج درجۀ ارجحیت طبقات و اهمیت لایه‌ها، امتیازات به‌دست‌آمده در نقشه‌های سامانة اطلاعات جغرافیایی اعمال و با استفاده از روش روی هم‌اندازی موزون نقشۀ آسیب‌پذیری بوم‌شناختی منطقه تهیه شد. با توجه به نقشة آسیب‌پذیری، نواحی غربی نسبت به دیگر قسمت‌های منطقه نقاط آسیب‌پذیری بیشتری دارند که لزوم توجه بیشتر به این مناطق را در طرح‌های مدیریتی نشان می‌دهد. | ||
| کلیدواژه‌ها | ||
| آسیب‌پذیری بوم‌شناختی؛ فرایند تحلیل توسعه‌ای؛ فرایند تحلیل سلسله مراتبی؛ ماتریس آثار متقابل؛ مجموعۀ حفاظت‌شدۀ توران | ||
| عنوان مقاله [English] | ||
| Identifying Ecological Vulnerability of Protected Complex of Touran via the Methods of Reciprocal Effects Matrix, AHP, and EA | ||
| نویسندگان [English] | ||
| Shahrzad Faryadi1؛ Hossein Sepehr2؛ Majid Ramezani3 | ||
| 1Associate. Prof. Faculty of Environment, University of Tehran, Tehran, Iran | ||
| 2Graduate student of Environmental Management and Planning, University of Tehran, Tehran, Iran | ||
| 3Post graduate student of Environmental Management and Planning, University of Tehran, Tehran, Iran | ||
| چکیده [English] | ||
| Introduction Ecological vulnerability is a common term that can be used in different hierarchical levels (animate, population, community, ecosystem, and landscape). Ecological vulnerability evaluation has lots of applications in environmental sciences such as EIA, risk assessment and environmental monitoring. This represents the importance of the evaluation. This paper aimed at assessing ecological vulnerability of the protected area of Touran (in East of Iran) using a combination of three methods of overlay, i.e., reciprocal effects matrix, AHP, and EA. So far, a large number of researches have been published about these methods around the world and Iran, as well. Some works in Iran are “Degradation Model” and Jabbarian's work which has innovations in objectifying ecological vulnerability assessment with reciprocal effects matrix approach. We can also point to zonation of environmental vulnerable and sensitive areas in west of Fars Province with method of fuzzy logic approach and AHP. Different methods have been used around the world to assess ecological vulnerability. Some of these methods are FAHP and compound the methods of AHP and GIS and also Multiway Data Analysis (MDA) for detecting relations between indicators, Reciprocal of Fractal Dimension (SPCA) and compounding ecosystem sensitivity and landscape pattern. More diverse indices have been used in the field of ecological vulnerability, so far. Some of these indices are ecological Sensitivity (ES), Natural and Social Pressure (NSP), Ecological Recovery Capacity (ERC) and the others related with landscape such as Reciprocal of Fractal Dimension (FD), Isolation (FI) and Fragmentation (FN). In this paper, indices of Ecological Sensitivity are used because these data are available in Iran. Materials & Methods Protected complex of Touran is in southeast of Shahroud City, southwest of Sabzevar City and in the north of great plain of Kavir in Semnan Province (from 55 to 57 E and from 34° 44' to 36° 22' latitude). For calculating ecological vulnerability, first of all the reciprocal effects m atrix must be prepared. In this method, a matrix of ecological factors in which if the points of an ecological factor effects on other factors they are given figure of one and otherwise figure of zero. In the next steps, the summation of rows and columns and the degree of importance of ecological factors is calculate based on following equation. n ij j i 1 S ( X X ) Where Sij is the degree of importance of ecological factor, Xi is the number of ones in the row of i and Xj is the number of ones in column of j. Then by comparing the degrees of importance of ecological factors, table of AHP of ecological layers was made for identifying the degree of preferences of layers. In fact, using reciprocal effects matrix, process of preferences turned into objective method in AHP. Extent Analysis Method used for calculating preferences degree of layers, the preferences for some of the layers would be negative; so simple AHP was used for calculating preferences degree of ecological factors. The Extent Analysis Method was used in FAHP for scaling classes of layers. In the Extent Analysis Method after supplying hierarchy decision tree, pairwise comparisons was accomplished; then, using Extent Analysis Method these qualities converted into quantitative values. Numbers used in this method is Triangular Fuzzy Numbers. In this method for each row of pairwise comparisons matrix, value of Sk which is Triangular Fuzzy Number, is calculated. n j m i n j k kj ij S M M 1 1 1 1 (1) Where k is the number of rows and i and j are alternatives and indices, respectively. After calculating S k s, magnitude degrees of them are obtained into each other. Generally if M1 and M2 are two Triangular Fuzzy Numbers, magnitude degree of M1 into M2 is calculated as: ( ) ( ) ( ) 1 1 2 1 2 1 2 1 2 V M M hgt M M otherwise V M M ifM M (2) Magnitude degree of a Triangular Fuzzy Number into K Triangular Fuzzy Numbers is calculated by this equation: V M M M V M M and and ( ,..., k ) ( ) ... 1 2 1 2 ( ) 1 k V M M (3) Also calculating weight of indices is obtained from pairwise comparisons matrix, thus: ( ) min 1 W x ( i k ) V S S (4) After scaling classes of layers and calculating preferences degree of layers, the obtained values are applied in maps by GIS and using weighted overlay. Ecological vulnerability map of the area was provided. Ecological layers used in this work are elevation and aspect with five classes and slope with eight classes gotten from 50 meter DEM, climatology with one class supplied by revised De Martonne, land use with seven classes, vegetation density eith six classes, soil depth with five classes, erodibility of soil with five classes, water erosion with three classes, and finally wind erosion also with five classes. Results and Discussion The most effective factor in ecological vulnerability that obtained through reciprocal effects matrix and AHP method (Fig. 1) was erodibility of soil.This factor affects extremely other factors such as soil depth, water erosion and wind erosion. The weight of this factor in AHP was obtained about 0.371. The climatology and elevation factors are lower than the erodibility of soil. They are with preference degrees of 0.161 and 0.137, respectively. In the end of the list both layers of soil depth and vegetation density are affected by other factors, with preferences degree of 0.16. Finally, the map of ecological vulnerability was obtained by weighted overlay of the layers and also by applying scales of classes for each layer. It is remarkable that location of the areas in sensitive geological zones, zones of deep soils, arid and warm climate, and wind erosion zones is determinant in vulnerability degree of those areas. These layers are converted into raster format and then overlaid by their weights; finally the map of ecological vulnerability was obtained as a result raster layer. For better land management, the area was classified by natural breaks method (Fig. 2) into four classes of resistant, subsensitive, sensitive, and vulnerable. Fig. 2. The map of ecological vulnerability for protected area of Touran Conclusions According to vulnerability map of the area, western parts are more vulnerable relative to other areas. Furthermore, most of the areas are placed in class of sensitive. Therefore, the protected area must be recognized in different managerial levels for more conservational acts. | ||
| کلیدواژه‌ها [English] | ||
| AHP, EA, Ecological Vulnerability, protected complex of Touran, reciprocal effects matrix | ||
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