Analysis of Morphological Factors in the Changes of Spatial Patterns of Alvand River

Alvand is a vital River in western Iran that forms Iran’s border for the length of 27 km. Recent droughts and special morphological infrastructure, have provided a possibility for variability in the geometric pattern and spatial distribution. Understanding and extracting such changes and the morphological factors behind them is the important subject of current research. For this purpose, the pattern of spatial changes of the river in the past half century (1334-1394), has been analyzed, using remote sensing images. In this regard, the length of the river was divided into 26 segments based on the current pattern, and geometric changes were analyzed based on vector maps derived from images taken from each of this parts. Finally, the important factors in these changes were mentioned. The findings represent a change in the geometric pattern of most parts of the river; so that in all the parts that were studied, the axis of the river has undergone a variability between 12 to 51 degrees. Changes in the spatial pattern of the river have been the consequence of geometric changes, the surface of the river has been reduced from 3,748,044 square meters in 1334 to 3,319,433 square meters in 1394. Research findings regarding the causes of these changes in the spatial and geometric pattern of the river, emphasize environmental factors, as well as the recent drought and human activities around the river as central factor influencing this change.