XML Persian Abstract Print


Abstract:  
Materials and methods: To assess the impact of land use changes on the hydrological behavior of the Khorramabad watershed, land use map using Landsat satellite imagery, CN and the runoff coefficient maps was prepared of the 1985, 2000 and 2016. The computer model for rainfall-runoff modeling HEC HMS has expectation methods to do research.
Result: The results showed the change land use has taken place in the region, especially deration of forestlands and increases in urban areas, which has resulted in an increase in peak discharge, runoff volume, runoff coefficient and the reduction of time of concentration, lag time and time to peak. So that the peak flow decreased for 1985-2000, 54.195 to 150 percent, for 1985-2016, 82.867 to 210.714 percent and in the period 2000-2016,18.594 to 24.285 percent and also time to concentration and time to peak, - 6.99 and- 5.02 in the period 1985-2016 has been changed, respectively. The results of running the model for return periods indicated with increasing returning time of rain, the amount discharge changes decreased. For example, in the period 1985- 2016 the rate of increase return times 2 and 100 years, 22.55 and 16.87, respectively.
Discussion and Conclusion: Land use changes vary in different parts of the land, including conversion of forestland to agricultural land, ranch and agricultural land to residential and urban areas and conversion of agricultural land into abandoned land. In the north and northwestern part of the basin, severe destruction of forests and its conversion to agricultural lands, and in the south and southwestern part of the basin, the conversion of agricultural and rangeland lands into residential and urban areas is observed; Particularly affected in these areas and causes CN increase.
     
Type of Study: Research | Subject: Sciences and Watershed Engineering
Received: 2019/11/16 | Accepted: 2020/04/26 | Published: 2020/06/30

Send email to the article author


© 2021 All Rights Reserved | Desert Ecosystem Engineering Journal

Designed & Developed by : Yektaweb