Effects of micro-catchment rain water-harvesting on survival and growth of multipurpose trees and Shrubs in Nyando District, Western Kenya

Abstract

The productivity potential of dry lands is usually low hence normal crop production is usually next to impossible. This places greater value on the perennial vegetation, especially multipurpose trees and shrubs which too require some form of water management. Sesbania sesban, Gliricidia sepium, Casuarina equisetifolia, Grevillea robusta and Eucalyptus grandis seedlings were planted on micro-basins, semi-circular bunds, V-shaped bunds, sunken pits and a control pit at the beginning of the rainy season in March 2007. The experiment was replicated three times. Survival rate, height and root collar diameter measurements were taken during planting and subsequent data collected after every two months throughout the study period of nine months. Data was analyzed by use of GENSTAT 5.0 and the significant means were separated using LSD at P ≤ 0.05. Use of micro-catchments improved seedling survival by between 32.1% and 85.7% while Individual trees species survival varied from 68.3% to 89.2% with Grevillea robusta being the best performer. The different species depicted significantly (P ˂ 0.05) better growth in height and Root collar Diameter (RCD) at different levels in micro-catchments as compared to the control. Micro-basins posted comparatively higher growth in both height and growth for all the tree species. The use of micro-catchments can improve the survival and growth of adaptable trees in semi-arid environments