Influence Buffer Zone Regimes Area on the Protected Tree Species Richness and Density in Kakamega Forest, Kakamega County, Kenya

Abstract

Buffer zone regimes (BZRs) enhance protection of forests in the world. For instance, they influence protection of about 50% in Latin America 30% in Sub-Saharan Africa and 63% in temperate countries. In Kenya, Nyayo Tea Zone (NTZ) was established as a BZR around all gazetted forests in early 1980’s. In areas where soils were not ideal for tea, Exotic Tree Plantations (ETP) was established. In spite of BZR in Kakamega forest, some section of BZR remains Open Edge (OE) probably because TEA and ETP did not thrive or as a result of poor management. In the past the trees that were abundant in Kakamega forest currently, remained threatened and some species rare possibly due to exploitation. However, studies on the influence of BZR (OE, ETP, and NTZ) area on tree species richness remain unknown in Kakamega forest. Therefore, the objective of this study is to examine the influence of BZRs area on tree species richness. Study population was unknown. Cross- sectional descriptive research design was employed. Saturated sampling was used to sample at least 40 humanly accessible along a string placed 100m from forest edge area interior gradient as it was assumed to be most disturbed area. OE acted as a control site assuming all the forest conditions were similar. A tape measure was adjusted along the string for identified plots. Study sites were located using hand held GPS. Trees were identified visually and counted. There was assumption of sources of errors for failure to come up with regular squares. Simple linear regression was used to assess the influence of BZRs (OE, ETP, and NTZ) area and the protected tree species richness. Results showed that NTZ 93% (r 2 =0.93, p = 0.000), ETP 82% (r 2 =0.82, p = 0.000) as compared to those in OE 68 % (r2 = 0.68, p = 0.000). The results implied that both NTZ and ETP were better supporting protection of the higher number of tree species richness as compared to OE.The study concluded that BZRs (OE, ETP and NTZ) area influenced tree species richness as opposed to OE. The study recommends the investigation onto the impact of NTZ and ETP on the health of trees in order to compare the health condition of the forest or its deterioration.