The water dynamics of cropping systems containing mixtures of Gliricidia sepium (Jacq.) Walp trees with maize (Zea mays L.) and/ or pigeonpea (Cajanus cajan L.) were examined during three consecutive cropping seasons. The trees were pruned before and during each cropping season, but were left unpruned after harvesting the maize; prunings were returned to the cropping area in all agroforestry systems to provide green leaf manure. The hypothesis was that regular severe pruning of the trees would minimise competition with crops for soil moisture and enhance their growth by providing additional nutrients. Neutron probe measurements were used to determine spatial and temporal changes in soil moisture content during the 1997/98, 1998/ 99 and 1999/00 cropping seasons for various cropping systems. These included gliricidia intercropped with maize, with and without pigeonpea, a maize + pigeonpea intercrop, sole maize, sole pigeonpea and sole gliricidia. Soil water content was measured to a depth of 150 cm in all treatments at 4-6 week intervals during the main cropping season and less frequently at other times. Competition for water was apparently not a critical factor in determining crop performance as rainfall exceeded potential evaporation during the cropping season in all years. The distribution of water in the soil profile was generally comparable in all cropping systems, implying there was no spatial complementarity in water abstraction by tree and crop roots. However, available soil water content at the beginning of the cropping season was generally lower in the tree-based systems, suggesting that the trees continued to deplete available soil water during the dry season. The results show that, under rainfall conditions typical of southern Malawi, the soil profile contains sufficient stored water during the dry season (ca. 75-125 mm) to support the growth of gliricidia and pigeonpea, and that gliricidia trees pruned before and during the cropping season did not deleteriously compete for water with associated crops. Water use efficiency also appeared to be higher in the tree-based systems than in the Ó Springer Science+Business Media B.V. 2006 sole maize and maize + pigeonpea treatments, subject to the proviso that the calculations were based on changes in soil water content rather than absolute measurements of water uptake by the trees and crops.

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Forests are vulnerable to climate change and are also major sources of livelihood for many rural households in Africa. This study examines rural people’s perceptions of climate change impacts on forest-based livelihoods using rural communities of Vhembe District in South Africa as a case study. The study was based on the principles of perceived impact-based assessment, and sustainable livelihoods framework. Using the stratified proportionate random sampling procedure in combination with weighted Enumeration Area for the selected communities, 366 households were chosen and interviewed. Data analysis involved computing frequencies and conducting the Chi-square, binomial tests and binary logistic regression analysis. The respondents identified erratic rainfall, extreme temperature, extreme drought and flooding as key climatic events in their community. But not all identified key climatic events were perceived to constitute risk to forest products and forest-based livelihood. Only extreme drought was indicated to constitute risk to availability of forest products. In addition, the binary logistic regression showed a significant difference (p < 0.05) in the perceived risk of climate change to the availability of essential forest products across the three municipalities. Hence the need for forest development initiatives that target vulnerable forest products per community as a means of enhancing resilience of forest-based livelihood to climate change impacts in rural community development in South Africa.