Effects of micro-cathcment water harvesting technique on young pistachio trees growth, soil and water conservation in semi- arid areas

Water harvesting techniques provide collecting rainwater to reduce the effects of water shortage and drought as well as the added benefits of soil and water conservation in dry areas. In this study, The Negarim microcatchment water harvesting technique was used in the young pistachio orchards established in sloping areas under rainfed conditions in the Southeast Anatolia Region.In this study, in order to transport the rain water to the root zone of the plant, 45 micro-catchments with different surface treatments including plastic sheeting, surface compaction, stone cropping and straw mulching, and control were considered. Soil water, runoff, sediment losses were measured and plant water consumption was estimated for three water years. According to the results, the annual average rainfall ranged from 250 to 350 mm in the experimental area, the average maximum runoff was 7090 L/plot in plastic cover. The average minimum runoff was 756 L/plot in stone cropping during the experimental years. Average maximum sediment loss was measured as 2870 g/plot in plots of the surface compaction plots, and average minimum sediment loss was 590 g/plot in stone cropping plots. The best erosion control was observed for micro-catchment surface covered with plastic sheet. This treatment was followed by straw mulching, soil surface compacting and stone mulching.Finally, in pistachio orchards established in sloping areas without irrigation, Negarim micro-catchment water harvesting technique was found to be useful and feasible technique to increase tree growth and yield, as well as conserving soil and water.