ASSESSING THE IMPACTS OF LAND USE ON SOIL EROSION IN T/A CHIWALO, PHALOMBE DISTRICT

Soil erosion is one of the most common types of environmental hazards which leads to land degradation and affects countries worldwide. Soil erosion hits developing countries the hardest as it reduces their economies especially for nations whose economies are dependent on agriculture, such as Malawi. In Malawi, erosion ranks as the number one environmental problem. The phenomenon occurs naturally under all climatic conditions however it is often exacerbated by human activities such as land use changes which are often influenced by social and economic factors. Land use which relates to land cover is one of the most important factors that affect soil erosion (Wijitkosum, 2012). In this study remote sensing techniques, ArcGIS and RUSLE model were used to estimate the soil loss rate and assess the land use change between 1998 and 2020, and to analyze the effects of land use and land cover changes on soil erosion in the area of T/A Chiwalo situated in Phalombe district. The study results revealed that the average soil loss rate in 1998 and 2020 were 29ton/ha/yr and 13ton/ha/yr respectively, the soil loss rates were categorized into 5 classes based on the severity of soil loss. In both 1998 and 2020 low erosion (0- 4ton/ha/yr) dominated in the area accounting for about 97.42% and 97.45% respectively whilst very high erosion (17-29ton/ha/yr) account for 0.02% in 1998 whilst in 2020 it accounted for 0%. Within these years the land use had also changed, the area initially covered by forests and bare land in 1998 significantly decreased by 2020 whilst the settlement and agriculture increased. The analysis of land use changes revealed that the changes in terms of the pattern and area influenced the erosion risk in the 1998 and 2020 period. The areas having little or no land cover showed higher erosion risk as compared to areas that had larger land cover. Analysis of the spatial distribution of erosion and land use in the area is essential for an agriculture-dependent country like Malawi and can be applied for guiding the development of conservation plans and controlling erosion under different land cover conditions and aiding decision makers.

In this study remote sensing techniques, ArcGIS and RUSLE model were used to estimate the soil loss rate and assess the land use change between 1998 and 2020, and to analyze the effects of land use and land cover changes on soil erosion in the area of T/A Chiwalo situated in Phalombe district. The study results revealed that the average soil loss rate in 1998 and 2020 were 29ton/ha/yr and 13ton/ha/yr respectively, the soil loss rates were categorized into 5 classes based on the severity of soil loss. In both 1998 and 2020 low erosion (0- 4ton/ha/yr) dominated in the area accounting for about 97.42% and 97.45% respectively whilst very high erosion (17-29ton/ha/yr) account for 0.02% in 1998 whilst in 2020 it accounted for 0%. Analysis of the spatial distribution of erosion and land use in the area is essential for an agriculture-dependent country like Malawi and can be applied for guiding the development of conservation plans and controlling erosion under different land cover conditions and aiding decision makers.

Phalombe is located in the Southern part of Malawi and it is bordered by Mulanje in the south and west, Zomba in the north and also shares an international boundary with the Republic of Mozambique in the east. It lies at the latitude -15.8064 and longitude 35.6507. Phalombe is made up of six main Traditional Authorities namely Jenala, Mkhumba, Kaduya, Nazombe, Chiwalo and Nkhulambe.

Traditional authority: TA Mkhumba

District: Phalombe

Coordinates: -15.6721, 35.6289