Human-induced changes to natural landscapes have been identified as some
of the greatest threats to
freshwater resources. The change from natural forest cover to agricultural and
pastoral activities is rampant especially in the upper Mara River catchment (water
tower), as well as along the course of the Mara River. The objective of this
study was to determine the effect of land use change on the physico-chemical
properties of soil (bulk density, carbon, nitrogen, phosphorus and pH) along the course of the Mara River. Five major land
uses (agricultural lands, livestock/pastoral lands, forested lands,
conservancy/game reserves, and natural wetland) were explored. Results revealed
that the mean soil bulk density was 0.956 g/cm3 and differed
significantly between sites (p < 0.001). Live
biomass values differed significantly between sampling sites (land use types) within
the Mara River Basin (F(4, 147) = 8.57, p < 0.001). The mean
infiltration over a period of 150 minutes differed, not only among sampling
sites, but also between different sides of the river (left and right) within
the same sampling site. Soil pH was generally acidic across the five sites and
varied significantly (F(4, 63) = 19.26, p < 0.0001) between sites along the Mara River Basin. The mean
percentage soil nitrogen across all sampling blocks was 4.87%, with
significant differences observed in percentage soil nitrogen (F (4, 63) = 3.26, p < 0.006) between sampling sites. The results indicated that the
five land use types affected land degradation differently along the Mara River,
while adjacent land degradation affected water physico-chemical properties. These results point to the need to
have focused policies on integrated land and water resource management
strategies in the Mara River Basin.