Rainwater Harvesting On Slope Land In Hilly Semi-arid Area And Water Saving Irrigation Technology

Atmospheric precipitation are various forms of water resources on land total supply source.Increasing the utilization of rainwater resource in arid is one of the effective measures to relieve the contradictions of agricultural water.this paper take Songshan Chengzi Township as the research unitand analyzed the amount of available rainwater in this district.Through the greenhouce water cellar experiments.the main results are as follows:1. Average annual rainfall is374mm in the Test area and preripitanon assurance stated in25%,50%.75%of rainfall of about460mm,374mm and2817mm,,available store rainwater resource potential is between165.16×104～269.71m3, Including farmland, roads and towns, as easier to implement the land type of rainwater harvesting project, the regulation of rainwater resources is150.69×104m3,2.The average runoff coefficient of sloping harvesting greenhouse roof surface is0.8443,the rain available amount of the single greenhouse is between in141.15m3～230.49m3.The rate of meeting the amount of water needed for two kinds of vegetables is58.8-96.4%.3.Compared with the low-pressure subsurface irrigation and irrigation.soil environment.air temperature and humidity were significantly improved in greenhouse, morphological index and yield were significantly improved.Under subsurface irrigation conditions, the best irrigation system of tomato in the whole growth. irrigation quota is2700m3/hm2,12times irrigation totally, watering quota is225m3/hm2.cucumber best irrigation system is irrigation quota3300m3/hm2. irrigation cycle10days, watering quota253.8m3/hm2.4. Annual investment is331.2yuan per Slope greenhouse With rainwater harvesting system. The net output value and the nilateral water of slope-field harvesting greenhouse ingle-crop cucumber and tomato was365838yuan/hm2.369840yuan/hm2,110.86yuan,136.97yuan respectively; counting by2520sloping greenhouse in demonstration area, it can reduce47.74×104m3of ground water extraction per year. In addition.iavoiding the surface subsidence and water erosion desertification.