Association between Forest Area Disturbed and Invasive Plant Species Abundance in Kakamega Forest, Kakamega County, Western, Kenya

Ecological disturbances are increasingly recognized as key drivers of biological invasions in tropical forests. Kakamega Forest, Kenya’s only remnant of the Guineo-Congolian rainforest, faces mounting human pressures that may facilitate invasive plant spread. This study examined the association between the area of forest disturbed by human activities and invasive plant species abundance, addressing the problem of rising invasions amidst limited spatial assessments of disturbance impacts. The study was conducted in Kakamega Forest, where sixty rectangular plots (10 m × 50 m) were systematically distributed along transects across different forest strata to ensure representative sampling of disturbance gradients and habitat heterogeneity. Primary data collection involved measuring areas (m²) disturbed by activities such as fruit gathering, footpaths, cultivation, fuel-wood collection, hunting, charcoal burning, medicinal herb extraction, and gold extraction, coupled with direct counts of invasive plant individuals. The research adopted a descriptive cross-sectional design, employed systematic sampling, utilized quadrat surveys, GPS mapping, and relied on direct visual enumeration as the primary data collection method. Data were analyzed using descriptive statistics, simple linear regression, and multiple linear regression. Simple regression revealed a significant positive relationship between total disturbed area and invasive abundance (β=0.48, t=5.33, p<0.001), explaining 52.5% of the variation (Adjusted R²=0.525). Multiple regression incorporating specific disturbance types improved prediction (Adjusted R²=0.673, F=19.2, p<0.001), highlighting cultivation (β=0.48, p=0.001), hunting (β=0.45, p<0.001), footpaths, and fuel-wood collection as leading contributors. The regression equation y=8.11+0.33x indicated that each additional m² of disturbance corresponds to an average increase of 0.33 invasive individuals. The study concludes that the spatial extent of human-induce