The land use changes study and precipitation-runoff modelling using HEC-HMS, Case Study: Babolrood basin

Change in land use pattern influenced hydrological processes in basin and disrupt the normal balance of water flow. In the present research, hydrological parameters change of Babul Rod watershed basin has been that investigated concluded of land use changes in 1988 and 2009. To determine land use changes of Babul Rod watershed basin we has recruited TM satellite images 1988(1367) year and ETM 2009(1388) year with factor of spatial resolution of 30 meters that using stratified classification classified into four types: urban, land of combined(urban, garden and garden spaces), agriculture-horticulture and bare land. According to the classification, forest and combined lands(agriculture, garden) of Babul Rod basin have encountered with area reduce and pasture and urban lands use have encountered with increase area. The HEC-HMS model is used for investigating the impact of land use changes of Babul Rod on hydrology cycle and factors quantify of hydrology Balance of the investigating watershed basin and analyzing relationship. The results of this model has shown clearly: reducing the precipitation losses, increasing elevation and runoff coefficient, increasing maximum rate of flow and increasing medium rate of flow, the impact of Babul Rod river morphologic changes and land use of its territory on flood factors.