Investigation and Estimation of Hydrological Effects of Caused by Land use Changes in the Ojan Chay basin (Sahand mountain range, northwest of Iran)

Type of land use and changes in the type of land use are related to the amount of runoff and changes in it. The type of land use with direct effects on runoff velocity, permeability and flood concentration control is controlled; in this case, a change in type of farming or pasture Urban use has a large impact on reducing water quality and increasing runoff from rainfall. Increased runoff due to user change can be a good indicator of the probability of increasing the flood in a basin. Land use change and land cover, in turn, have hydrological results at local, regional and global scales. The hydrological effects of land use and vegetation management are evident in the form of changes in runoff depth, minimum discharge, maximum discharge, soil moisture and evapotranspiration.Due to the type of soil and topographical and climatic characteristics of the Ojan Tea (from the sub-basins located on the eastern slopes of the Sahand Mountains), changes due to man's loss to slopes and land use changes have been high. Considering the inducements caused by Erosion erosion and general ablation in the range of Ojan tea, it seems that variations in runoff rates are very significant due to changes in the range of the desired range.