عنوان مقاله [English]
Urban open spaces are invaluable assets in maintaining ecological health in a highly developed urban matrix. Unfortunately, habitat values and ecological quality of these areas are often challenged by consecutive urbanization. The assessment of changing structure and function of an urban space system is crucial in maintaining livable cities. General characteristics and type of open spaces are investigated in case study – Mashhad city. The possible impacts of urban landscape change on the ecological qualities of natural open space patches are explored by using a landscape structure indicator. Even though various conceptual and analytical approaches exist in measuring the ecological integrity of natural systems, in this paper specifically deals with isolation issues. Because an isolated open space system loses its ecological integrity, isolation index yields meaningful result for anticipating the possible threats generated by urban structure. Isolation trends of urban open spaces are displayed. Also, numbers yielded by the isolation index presented. GIS seems to be an appropriate tool to evaluate the intricate attributes involved in the phenomenon. Black- white and colored aerial photographs of the city of Mashhad in various date and other data are available are used for the analysis in GIS environment. The results show some eye-opening facts with regards to the planning and management of urban open spaces, and possible threats to the ecological viability of theses precious areas in the future.