Influences of land use land cover change and topography on selected physicochemical properties of soils developed from sandstone dominated area of Abrha-We-Atsbeha watershed in Northern Ethiopia

The study was conducted to investigate the influence of LULCC and topography on selected physicochemical properties and soil quality index (SQI) of soils developed from sandstone-dominated areas in the AWA watershed, Northern Ethiopia. Eight representative soil profile pits were opened; from those, 46 total soil samples were collected and analyzed for physicochemical properties and SQI using descriptive statistics. Plot-level surveys through questionnaires and focus group discussions were used to assess management options of land use and SQI. The study showed that from 1990-2019, cultivated and bare land decreased by 4.34% and 3.8%, whereas settlement, bush, and grazing lands increased by 2.04, 5.44, and 0.66%, respectively. Soil color showed that (5YR ¾), (7.5 YR4/3), and (3.5YR 5/6) were wet at the surfaces and (7.5 YR ¾), (7.5 YR4/3), and (10YR 2.5/n) were wet at the subsurface in pits 1, 2, and 3, respectively. Sand, clay, and moisture content were significantly varied in land use type at P < 0.05, and clay significantly differed on slope gradient at F (2, 19) = 4.39, p < 0.05. Almost all selected chemical properties have no interaction effect of land use type and slope except K+. The study area's soil reference group was divided into the following categories: fluvisols, regosols, arenosols, cambisols, and leptosols. The result of principal component analysis indicated that the overall average SQI was low, i.e., 0.53. Generally, LULCC is more highly influenced than the slope of the selected physicochemical properties and SQI. Using appropriate management of land is good for developing SQI instruments and services.