雨滴击溅对耕作层土壤团聚体粒径分布的影响

发布时间：2018-03-31 09:35

本文选题：侵蚀　切入点：团聚体　出处：《农业工程学报》2017年03期

【摘要】：为研究不同雨滴直径的降雨对耕作层团聚体的破碎及其粒径分布特征的影响,该文选取4个雨滴直径(2.67~3.79 mm)对耕层土壤(0~20 cm)团聚体进行雨滴击溅试验,每次试验各滴5 000滴,每1 000滴收集1次溅蚀团聚体。结果表明:1)所有收集次序中雨滴直径3.79 mm溅蚀量最大,累积雨滴数为2 000、3 000和4 000时,溅蚀量与雨滴直径均呈显著的指数函数关系。2)各雨滴直径的溅蚀量随粒径减小呈增大-减小-增大趋势,2 mm粒径的溅蚀量几乎为0,0.053 mm粒径的溅蚀量随雨滴直径增大而增大。3)相同雨滴直径不同累积雨滴数之间平均重量直径值差异不显著,相同累积雨滴数不同雨滴直径之间平均重量直径值差异不显著(P0.05)。4)不同雨滴直径溅蚀团聚体富集率随粒径变化一致,1 mm粒径溅蚀量团聚体富集率值接近0,0.053~1 mm粒径团聚体富集,1 mm粒径团聚体主要破碎成0.053~1 mm粒径团聚体,且粒级越小,富集率越高。研究可为黄土高原地区水土保持提供理论依据。
[Abstract]:In order to study the effect of rainfall with different raindrop diameters on the fragmentation and particle size distribution characteristics of aggregates in tilling layer, four raindrop diameters (2.67 ~ 3.79 mm) were selected to carry out the raindrop splash test on the topsoil (20 cm) aggregates, each of which was 5 000 drops. The results show that the raindrop diameter of 3.79 mm is the largest in all the collection sequences, and the cumulative raindrop number is 2 000 ~ 3 000 and 4 000. Spatter amount and raindrop diameter have significant exponential function relationship. 2) the splash erosion amount of each raindrop diameter increases with the decrease of the diameter of the raindrop. The trend of splash erosion is increasing with the decrease of the diameter of the raindrop. The splash erosion amount of the diameter of 2 mm is almost 0 ~ 0.053 mm. The amount of splash erosion increases with the diameter of the raindrop. The difference of mean weight diameter between the same raindrop diameter and cumulative raindrop number is not significant. No significant difference in mean weight diameter between different raindrop diameters (P0.05 路4) the enrichment rate of splash erosion aggregates with different raindrop diameters is the same as the variation of particle size. The enrichment rate of aggregates is close to 0 ~ 0.0531mm in diameter. The aggregates with a diameter of 1 mm were mainly broken into 0. 053 ~ 1 mm aggregates. The smaller the grain size, the higher the enrichment rate. The study can provide a theoretical basis for soil and water conservation in the Loess Plateau.
【作者单位】：西北农林科技大学水土保持研究所;西北农林科技大学资源环境学院;绵阳市农业科学研究院;中国电建集团华东勘测设计研究院有限公司;
【基金】：国家自然科学基金(41571262)
【分类号】：S157.1

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