The effect of altitude and Soil-Adjusted Vegetation Index on soil organic carbon and other soil properties across the mountainous landscape in West Usambara, Tanzania

Abstract

This study was conducted in West Usambara to assess the effects of altitude and SAVI (Soil-Adjusted Vegetation Index) on soil organic carbon (SOC) and other soil properties within the plateaued mountainous landscape. Soil sampling, laboratory, and statistical analyses were undertaken. The correlation analysis results demonstrated an increase in SOC and Total Nitrogen (TN) with altitude. Altitude exhibited a negative correlation with available phosphorus, soil pH, exchangeable bases (Ca, K, and Na), and cation exchange capacity (CEC). The SOC and various soil properties, such as TN, exchangeable bases (Ca, K, and Na), and cation exchange capacity (CEC), exhibited an increase in correlation with the SAVI. Soil pH exhibited a decline as SAVI levels increased. The study's results are significant for land management practices, highlighting the importance of considering altitude and SAVI in optimizing SOC and nutrient content to enhance soil fertility and productivity in the study area.