تحليل مناسبت محيطي GIS پايه براي حفاظت از نواحي طبيعي باارزش در چارچوب برنامه‌ريزي محيطي

GIS-based Environmental Suitability Analysis for Conservation of Valuable Natural Areas in the Context of Environmental Planning

شهر رشت و محيط پيرامون آن با انواع مشكلات مرتبط با اُفت مرتبه محيط طبيعي دربرگيرنده تخريب زمين‌هاي كشاورزي و جنگلي واقع در محيط پيرامون شهر، نابودي اكوسيستم‌هاي طبيعي باارزشي چون رودخانه‌ها و تالاب‌ها، انتشار آلاينده‌هاي محيطي و انباشت آنها در زيستگاه‌هاي طبيعي و رشد افقي و گسترش كالبدي شهر به‌ سوي نواحي طبيعي باارزش روياروست. در پاسخ به ناكارآمدي رويكردها و رهيافت‌هاي سنتي برنامه‌ريزي شهري در رويارويي با انواع مشكلات اُفت مرتبه محيط طبيعي، به كارگيري رهيافت جديد "برنامه‌ريزي محيطي" و لزوم برنامه‌ريزي به جهت حفاظت از محيط و نگهداشت منابع طبيعي مورد نظر و تاكيد بسياري از صاحبنظران برنامه‌ريزي قرار گرفته است. يكي از مهم‌ترين زمينه‌هاي عمل برنامه‌ريزي محيطي تشخيص نواحي است كه از نظر محيطي منحصر به فرد يا در وضعيت بحراني‌اند. از مهم‌ترين فنون مورد استفاده توسط برنامه‌ريزان محيطي براي شناسايي نواحي طبيعي باارزش و نواحي كه از نظر بوم‌شناختي حساس هستند، "فن تحليل مناسبت محيطي" است. هدف از اين مقاله معرفي رهيافتي است كه براي پرداختن به موضوع تحليل مناسبت محيطي براي شناسايي نواحي طبيعي باارزش و مناسب‌ترين نواحي براي حفاظت محيطي، "فنون تصميم‌گيري چندمعياري" و به طور خاص "روش تركيب خطي وزني" را با فناوري GIS يكپارچه مي‌كند. مطالعه حاضر بر اين فرضيه مقدم استوار است كه تحليل مناسبت حفاظت محيطي مي‌تواند به عنوان پايه و اساسي براي تصميم‌گيري و تدوين سياست‌ها در چارچوب رهيافت برنامه‌ريزي محيطي به كار رود. براي دستيابي به اين هدف ابتدا با استفاده از روش‌هاي تحقيق ميداني و اسنادي، مشكلات مرتبط با اُفت مرتبه محيط طبيعي شهر رشت و محيط پيرامون آن شناسايي مي‌شوند. سپس بر پايه روش تحقيق توصيفي و با طراحي و تكميل پرسشنامه، نظرات شهروندان درباره اهميت و وخامت مشكلات مرتبط با تخريب محيط طبيعي بررسي و تحليل و در نهايت با به كارگيري فن تحليل مناسبت محيطي جي آي اس-پايه، نواحي داراي مناسبت بالا براي حفاظت محيطي و نواحي مناسب توسعه شهري تعيين مي‌شوند. نتايج پژوهش مزيت تلفيق فنون تصميم‌گيري چندمعياري و GIS را در شناسايي نواحي طبيعي باارزش و سپس تدوين سياست‌هاي محيطي كارا در چارچوب رهيافت برنامه‌ريزي محيطي براي هدايت گسترش كالبدي شهر و جلوگيري از افزايش و انباشته شدن مشكلات مرتبط با تخريب محيط طبيعي شهر رشت و محيط پيرامون آن نشان مي‌دهد. برآمد رهيافت توسعه يافته مي‌تواند به عنوان پايه‌اي براي برنامه‌ريزان و تصميم‌گيرندگاني مورد استفاده قرار گيرد كه با توسعه شهرها و محيط پيرامون آنها در نواحي سروكار دارند كه از نظر بوم‌شناختي بسيار حساس هستند.

The city of Rasht and its surrounding as a result of the growing trend of physical expansion of the city and urban sprawl into its surroundings have been encountered with environmental problems associated with degradation of natural environment including problems such as destruction of farmlands and forestlands around the city, destroying valuable natural ecosystems such as rivers and wetlands, environmental pollutants emission and municipal solid wastes accumulation in natural habitats as well as horizontal growth and physical expansion of city into natural areas which are precious that these problems altogether have led to environmental degradation of this city. Due to inefficiency of traditional urban planning approaches in dealing with the problems associated with degradation of natural environment, applying the new approach of environmental planning and necessity of planning for environmental protection and natural resources conservation has been emphasized by some of the urban planning scholars. One of the most important action fields of environmental planning is identification of areas that are environmentally unique or are in critical conditions. Environmental suitability analysis is one of the main techniques used by environmental planners to identify valuable natural areas and ecologically sensitive areas. Land suitability analysis is the process of determining the suitability of a tract of land for some specific uses, as well as determining the level of suitability. Suitability techniques can enable decision-makers in a variety of ways to analyze the interaction between three factors: location, development measures and environmental elements. Suitability analysis may show land-uses that have the least detrimental effects on environmental processes, predict environmental impacts of the proposed developments or find the most suitable and the most unsuitable locations for specific development projects. Government officials and private sector developers can use suitability maps for formulating policies and decision-making about land uses. Suitability techniques are necessary to make informed decisions. Environmental suitability analysis can be used to identify areas that have important resources that must be protected and areas that are not environmentally sensitive and development will not have serious effects on their values.Land suitability analysis is a complex task due to the tension between the need to develop residential and industrial areas, and the desire to maintain biodiversity and heterogeneous landscapes. It is essential that conservation of biodiversity be the aim of efforts of policy-makers, ecologists and resource managers to maintain and rebuild communities, ecosystems and landscapes. The extent of the problem of destruction of natural environment is worldwide. However in areas of high ecological sensitivity has been increased. The case study of this research- the city of Rasht and its surroundings- is located in an ecosystem that have high ecological sensitivity and faced with problems of destruction of natural environment and horizontal growth and physical expansion of the city into the valuable natural areas.The main purpose of this paper is to introduce an approach that integrates multi-criteria decision-making techniques and in particular the weighted linear combination method with GIS technology to address the issue of environmental suitability analysis for identifying areas which are naturally valuable and the most suitable areas for environmental conservation. This study in based on the premise that successful environmental suitability analysis can be used as a basis for decision-making and formulating policies in the framework of environmental planning approach. To achieve the purpose of this paper, the following process will be followed: First- Theoretical and Technical foundations related to environmental suitability analysis are reviewed. Second- The environmental problems associated with degradation of natural environment of the city of Rasht and its surroundings will be identified, analyzed and discussed by combining the results of two parallel paths: a) Field observations and applying documentary method of research for determining problems which can be found from analysis of the planning documents and b) using descriptive method of research, preparing and completing the questionnaires and analyzing them with the assistance of SPSS software to detect environmental problems in Rasht based on citizens’ views. 119 questionnaires were filled out by citizens about issues querying and surveying environmental problems. Third- valuable natural areas and the most suitable areas for environmental conservation will be identified by applying GIS-based environmental suitability analysis and considering environmental criteria for this analysis which could be considered as a basis for decision-making and formulating effective environmental policies in the context of substantive and procedural principles of environmental planning approach to guide physical expansion of the city and prevent increasing and accumulating problems associated with destruction of natural environment of this city. Achievement/ Value: The final achievement is to use the advantage of integrating multi-criteria decision-making techniques with GIS technology to identify valuable natural areas and then developing effective environmental policies in the context of environmental planning approach to direct physical expansion of Rasht and prevent from increasing and accumulating problems regarding degradation of natural environment of the city of Rasht and its surrounding. This framework can be helpful for natural resource management and urban planning in the areas which are ecologically sensitive.