Application of GIS and Remote Sensing Techniques for the Estimation of Soil Erosion- Case Study: Soan River Catchment

Abstract

Soil erosion has seriously endangered the agricultural and water resource projects. As a result, the environmental issues are also increased due to the considerable amount of soil erosion at the catchment along with the agricultural land. Poor land management, deforestation, and overgrazing have reduced the natural vegetation, triggering overflow and soil loss. Soil loss data is critical for managing natural resources and boosting agricultural productivity. The majority of Pakistan is classified as having an arid climate which receives little to no rain and semi-arid climate which receives slightly higher rain than the arid climate. Before entering the Indus Basin System, nearly all hilly nullahs and hill torrents that originate from these regions' mountains receive non-perennial flows and go through substantial stretches of levelled and fertile land. These steep torrents provide flashy floods that are more intense and last for a shorter time. Flood flows travel quickly due to steep gradients, causing damage to standing crops, irrigation systems, homes, roads, and etc., as well as occasionally human life. In fact, if managed properly, these hill torrents have a great deal of potential for agriculture product to make up for the lack of food and raw materials for agro-based industries. One of Punjab Province's most significant hill torrents is the Pothowar Hill stream. Since the Pothowar area's geography is categorized as plateau and contains sporadic gulleys and deep valleys throughout, no substantial canal system can be constructed there. The provision of a local irrigation system for a solitary, tiny parcel of land with a uniform topography is mandated by the region's physical characteristics. However, unless storage systems have been made, most of the hill torrent flood flows are wasted. Punjab's Barani (rain fed) Tract (PBT), which includes the districts of Rawalpindi, Attock, Jhelum, and Chakwal, makes up around 40% of the plateau (PBT). Performing a soil erosion investigation requires a lot of effort and money. To predict soil erosion at drainage basins, several parametric models have been created. In this study, the proposed model used the methods described by Revised Morgan-Morgan-Finney model encapsulated with GIS (Geographic Information Systems) and RS (Remote Sensing). Based on the soil erosion rate in the watershed, this study also covered the effects of topography, soil erodibility, and drainage density. For rainfall intensity, LU/LC change, soil erosion, kinetic energy, and surface overflow, GIS maps have also been created. To map and estimate the annual soil loss of the study area, analysis of the Morgan parameters has been done in ArcGIS using raster calculator from the geo-processing tools. In the watershed, the annual soil loss in 1990 was 54.04 kg/m2 as there was most of the area consist of barren land, while in 2020, it is 41.09 kg/m2 as the barren land is converted in to Agricultural as well as built up land. Keywords: Soil Erosion, Remote Sensing, GIS Application, Revised Morgan-Morgan-Finney model, LU/LC, Soan River.