عنوان مقاله [English]
In recent years, planning efforts have focused on environmental issues, such as how to direct and manage development to minimize the damage to the environment. Decisions made at the planning stage, irrespective of the natural and physical environment, can move against the needs of proper land planning and planning. National planning should focus on the spatial tasks of each area, commensurate with its ecological potential and the allocation of physical development factors. Therefore, in designing strategies and policies for urban planning departments, one should consider the ecological potential of development and design the optimal model for it. Nowadays, research in the world of environmental modeling is of great importance. Environmental models represent the obvious aspects of complex and changing environments. In Iran, too, since the validity of ecological models has not been studied for urban development using GIS and landscape, despite decades of use, so with the advancement of technology, it is necessary to develop ecological modeling first. Complete the city and then conform to the landscape and its metrics.
It is a city that has an identity in terms of its role and appearance in environmental planning and its location in space is quite evident. It is therefore considered to be an ecological structure that is governed by a system. The task of environmental planners is to study and analyze the ecological structure in the form of a set of components that interact with each other in an environmental system, in the form of organizing forms and populations, so that the urban complex is in the process of development and evolution. Due to its spatial context, its historical context manifests itself as an ecosystem in which these relationships manifest themselves. Therefore, urbanization and urban development can undoubtedly be one of the deepest aspects of modern civilization, one of the most important factors in environmental change, and this is the reason that the ever-increasing need for land for natural resources and products and products is growing. It causes food. But overcrowding has resulted in the concentration of activities and abundance of construction, the physical growth and expansion of urban hubs and the destruction of natural ecosystems. Although urban development in industrialized countries has been slow in the last centuries, it has intensified in developing countries after World War II, and these cities are expanding more rapidly than industrialized cities. As cities are growing in all dimensions, the growth of metropolis in developing countries is more than in developed countries.
From an environmental point of view, the best location for a type of land use (urban, rural, industrial, conservation, agricultural, etc.) is the place where the least burden and pressure is put on the environment. Environmental assessment is a tool to help achieve sustainable development. The most important purpose of an environmental assessment is to ensure compliance with the policies and objectives set forth in the plans and activities of a plan or project in accordance with government environmental standards, criteria, laws and regulations Monvari, 2001). There are numerous methods to evaluate all of which attempt to standardize human use of nature on the basis of sustainable development. Common evaluation methods in the world are based on identifying the environmental resources that affect a region's power and suitability for given uses, integrating information, and ultimately using fitness models to determine the best use or uses. Land use models are useful tools for understanding land use process and supporting land planning and policy making (Verburg et al., 1999) and modeling is a valuable and useful method for understanding a process (Costanza and Ruth, 1998). ). In Iran, land evaluation and classification is done by comparing the ecological characteristics of environmental units and ecological models. The models presented for Iran are a general guide and, depending on the study site, the identified data and the purpose of the land use, it is appropriate to construct a specific model for the subject under evaluation in the framework of the Iranian Ecological Models and evaluate with the help of the model. Specifically reach the end (Makhdoom, 1999).
In this research, it has been tried to make changes in Shiraz city and its range based on land use changes between three time periods and two periods of 2010 and 2015 and second period 2015 and 2019 based on satellite images extracted from Landsat series. After studying the changes and extraction and comparing them, three periods of Landscape changes of the study area and its changes in different skips have been studied and finally modeling of Shiraz city development with regard to ecological conservation and optimal development of the area has been discussed.
Results and discussion
As mentioned, one of the land uses that has been very important for human habitation since long ago is urban land use (Moharramnejad, 2004). In Iran, an ecological model with three classes of power has been proposed to evaluate the ecological potential of urban development land use. This model includes basic information such as climate, geographic direction, sea level, slope percentage, texture and soil type, soil drainage conditions, soil depth, soil structure, vegetation density, geology, water quantity, Grounding power and quality (land classification) are used to carry out urban development land use. In this research, it is intended to test the degree of validity of existing ecological models and to improve the statistical-mathematical relationship. This survey will be a milestone in environmental planning and land use planning in Iran and will begin the fourth stage of environmental assessment, namely the use of GIS.
It can be said that the implementation of the environmental case analysis process is highly dependent on the case analysis information. But in general, the study-analytical process showed the lack of spatial expansion in zones which in the present conditions strongly witnessed unplanned development without a city plan. Physically located, 38 percent of the area is suitable, while only 23 percent of the city's area is in an appropriate physical development area in terms of environmental hazards and ecological zones.