Effect of Human Settlement and Altitude on Rangeland Browse Woody Species Biodiversity and Productivity in Kafta-Humera Woreda, Tigray, Ethiopia

Abstract

A research was conducted in Kafta-Humera districts of the Northern Ethiopia with the objective to determine the effect of human settlement on rangeland wood species productivity and biodiversity under three altitudinal ranges (600-1000, >1000-1400 and >1400-1800 m.a.s.l.) and along three distance intervals near (0-2 km), middle (2-4 km) and far (4-6 km) from settlement. The Statistical Package for Social Sciences (SPSS, version 16.0, 2013) was used to analyze the soil and vegetation data. In the study districts, a total of 46 woody species were identified. Browse biomass of woody species in the low, middle and upper altitude categories were, 180.47, 225.97 and 243.72 kg ha-1, respectively. Browse biomass of woody species near, middle and far distance from settlement were, 145.30, 228.03 and 276.824 kg ha-1 respectively. Woody species diversity was increased with increasing altitude, and was significantly lower near to settlement than middle and far distance. Far distance from settlement had significantly higher in organic carbon, available phosphorus and available potassium than middle and near distance from settlement. The upper altitude had significantly higher organic carbon, organic matter, available phosphorus and available potassium than the lower and middle altitude. In conclusion, the study area was highly dominated by the thorny shrubs woody species. This implies that there is undergoing reduction biodiversity and productivity degradation. Therefore, appropriate plan of biodiversity conservation such as establishing, designing and implementations of watershed management for physical and biological conservation should be planned to minimize loss of biodiversity. Keywords: Settlement, plant Species composition, plant species abundance, plant Species diversity, biomass production