[M-ZZ50] Studies of Geoscience : historical, philosophical and STS studies

[MZZ50-P01] Soil Erosion in Gandaki Province, Identifying The Most Sensitive Watersheds

*Ajaya Shrestha¹, Rabin Raj Niraula (1.Environment and Engineering Research Center Pvt. Ltd)

Keywords:Erosion, RUSLE, Watersheds, Gandaki Province

Gandaki Province is vulnerable to water erosion due to its topography, fragile geology, and high rainfall. On the other hand, Mustang and Manang districts are vulnerable to erosion due to highly fragile lithology. This study aims to evaluate the sensitive watersheds in Gandaki province based on the soil erosion estimation using the RUSLE method. The application of the RUSLE method is efficient in the estimation of Soil erosion based upon the predefined factors. The state-of-the-art data used in the study are Rainfall, Soil map 2020, SRTM 30m DEM, Sentinel 2 imageries for 2020, and land use map which improves the soil erosion estimation in the country compared to similar studies conducted in the past.


As per the RUSLE estimation method, the study estimates that from an area of 2.19 million hectares in Gandaki province, 14.24 million tonnes of soil is lost every year.

Watershed-wise erosion estimation suggests that Kaligandaki, Marsyangdi, Budhi Gandaki, and Seti watersheds are among the most sensitive watersheds in terms of soil erosion. The dissection of provinces into watersheds provides an important criterion to evaluate the sensitivity of watersheds based upon soil erosion estimation. This helps the policymakers and planners to execute effective soil conservation management interventions.