Management of windbreaks in the Sahel: the strategic implications of tree water use |
| |
| Authors: | D M Smith P G Jarvis J C W Odongo |
| |
| Institution: | (1) Institute of Ecology and Resource Management, University of Edinburgh, Mayfield Road, Edinburgh, EH9 3JU, United Kingdom;(2) Institute of Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire, OXIO 8BB, United Kingdom;(3) ICRISAT Sahelian Centre, B.P. 12404 Niamey, Niger |
| |
| Abstract: | At sites in the Sahel where windbreaks are used to control wind erosion, management strategies are required to minimise competition for water between trees and crops. Uptake of water by windbreak trees was therefore studied in experiments designed to compare water use among tree species, assess which variables exert most control over transpiration and determine the source of water transpired by windbreak trees. Transpiration and soil-water extraction by Acacia nilotica, Acacia holosericea and Azadirachta indica trees in windbreaks were measured at the ICRISAT Sahelian Centre, Niger. Coupling of windbreaks to the atmosphere was evaluated and a stable isotope technique was used to compare utilisation of groundwater by windbreaks and crops at two sites in Niger with different water table levels. Azadirachta indica used least water, probably as a result of lower stomatal conductances, since windbreaks exhibited good physiological control over transpiration. The potential for competition for water was most severe with Acacia nilotica and Acacia holosericea, as they extracted large quantities of water through lateral roots, and at the location where trees could not access groundwater. At such sites, the effects of competition on crop productivity should be minimised by planting tree species with low water requirements and by using pruning to limit tree transpiration.This revised version was published online in November 2005 with corrections to the Cover Date. |
| |
| Keywords: | competition complementarity groundwater transpiration |
| 本文献已被 SpringerLink 等数据库收录！ |
|
