Recognition of Perimeter Border Fluctuations and Draw-up Suspended Materials Scattering Map of Urmia Lake, Using Satellite data (ETM, TM and LISSIII Sensors)

Abstract
Identification & supervision of fluctuations in physical ecosystems have a special place in optimum using of natural resources. Urmia lake is the largest interior natural lake of Iran which its potentials and ecosystem & environmental characteristics attracted researchers and environmental planners attention. Fluctuations in area and perimeter of the lake attracted many attentions in recent years and some reasons presented for that, but there is not a documentary research in the matter, yet.
We used satellite Landsat TM, ETM images and LISS? all together with time resolutions of 1987, 1998, 2001, and 2002 to determine area fluctuations and providing distribution of suspended material map of the lake. Also, we used on screen digitizing for extracting perimeter borders of the lake in time periods after processing and detecting of images and then for providing distribution of suspended material in the lake, we used clustering method. The results of research shows that, maximum area of the lake was in 1998 and minimum attributed to 2002. Also the research shows that suspended material pattern, which indicated the amount of deposited, and concentration of material, in margins of martyr kalantary expressway, is recognable and their distribution pattern has remarkable fluctuations in periods of time. This shows that environmental changes are happening in the region. In this paper someprobable affecting factors in the fluctuations considered and some suggestions for further studies presented, also.

Keywords: Urmia Lake, Suspended material, Border fluctuations, Satellite data, Remote Sensing