Lithological and Topographic Impact on Soil Nutrient Distributions in Tectonic Landscapes: Implications for Pleistocene Human-Landscape Interactions in the Southern Kenya Rift

Tectonically active regions are characterized by complex landscapes comprising soils with heterogeneous physicochemical properties. Spatial variability of nutrient sources enhances landscape biodiversity and creates habitats potentially attractive for animals humans. In this study, we analyze the role geological processes in distributions soil nutrients southern Kenya Rift, a key region interpretation early human-landscape interactions. Our aim is to determine how spatial variations rock chemistry, as well topographic gradients localized zones fracturing from tectonic faulting plant-available soils. We hypothesize that present-day levels reflect long-term chemical geomorphological characteristics underlying parent material, high availability occur along pathways correlating locations hominin fossil sites. Analyses 91 topsoil samples main units show Calcium (Ca) deficiencies predominately shallow developed on trachytic volcanic rocks granitic gneisses, while Ca associated basaltic material sedimentary deposits mixed sources. XRF analysis confirms CaO trachyte significantly lower than those basalts, mobilization basalt more effective trachyte. Along two toposequences densely faulted rocks, observed slope dependent nutritional systematic increase concentrations Ca, Mg SOC topsoils colluvial sediments downslope normal faults. Known sites located either corridors or at short-term hotspots related CO 2 degassing fault zones. This implies strategic advantage Ca-rich subsistence strategies, such provision predictable constraints distribution mobility grazing landscapes. study impact Rift. Results have further implications understanding hominin-landscape interactions stages human evolution.