具有水窖设施的梯田苹果地抗暴雨侵蚀研究

Study on Anti-erosion in Apple Orchard Terrace with Water Cellar

针对2013年延安地区极端暴雨径流侵蚀条件下土壤侵蚀严重、水土资源利用效率低等问题,通过对陕北安塞县方塔村带有水沙调控措施的梯田—水窖—苹果水土流失状况进行定位监测,基于收集的降雨资料,研究该梯田内水沙调控措施在抗御暴雨条件下的防蚀作用和土壤侵蚀规律,结果表明:该梯田能够抗御暴雨的冲刷,各阶梯田土壤侵蚀都在中度侵蚀以下,平均土壤侵蚀模数仅为该区多年平均的1/7。集中性的高强度降雨对黄土高原土壤侵蚀起决定性作用,本文基于安塞水土保持试验站坡面土壤侵蚀预测预报模型,给出了适宜该区具有水沙调控措施的梯田土壤侵蚀预测预报模型,得到在I30=0.24mm/min前提下,当年降雨量小于191.1mm时,土壤能够维持较高的生产力;当年降雨量小于997.13mm时,该区土壤侵蚀模数可控制在多年平均水平以内。梯田内修建的水窖、梯壁植草、地表枯枝落叶以及梯田质量等因素的综合作用在抗御暴雨侵蚀过程中起到了重要作用。

In order to solve the problem of severe soil erosion and low use efficiency of water and soil re- sources, based on the collected rainfall data and field soil erosion monitoring in terraces with water and sedi- ment regulation measures in Ansai County, north Shannxi Province, we analyzed the anti-erosion effect and mechanism of soil erosion in terraces with water and sediment regulation measures in the process of resisting the rainstorm disaster. The results showed that the terraces had the ability to resist rainstorm erosion with the degree of all the levels of terraces with middle erosion, and the average soil erosion modulus was one-sev- enth of annual mean value. Concentrated and high intensive rain played an important role in contributing to soil erosion modulus. Based on the corrected soil erosion forecasting model that is fit for the terraces in this region, when /30 is 0. 24 mm/min, soil can maintain high productivity if annual precipitation is less than 191.1 mm,and soil erosion modulus can be controlled within annual mean value if annual precipitation is less than 997.13 mm. The comprehensive effects of cellar constructed in the terrace, planting grass on the side slope of terrace,the litter mulch on the terrace and terrace quality played the important role in resisting the rainstorm-induced disaster in the terrace.