黑钙土不同土层在两种材质负压渗水器下的吸渗特性

发布时间：2018-03-07 14:45

本文选题：土壤层次　切入点：渗水器　出处：《土壤》2017年04期 　论文类型：期刊论文

【摘要】：基于 5 k Pa负压灌水条件下的一维垂直水分吸渗试验,分析了陶土和聚乙烯醇缩甲醛泡沫塑料(PVFM)两种材质负压渗水器在黑钙土A、B层的渗水性能,测定累计吸渗量、吸渗率、湿润峰及土壤含水率等指标,并利用它们考察了Kostiakov,Horton、Philip 3种常用的土壤水分吸渗模型及垂直一维非饱和土壤水分运动代数模式描述负压吸渗过程的适用性,进一步比较了不同处理下的模型参数。结果表明:(1) 5 k Pa灌水条件下,PVFM渗水器和陶土渗水器的累计吸渗量没有明显差异,前者能有效替代后者作为负压渗水器;(2)黑钙土B层土壤水分吸渗特性比A层差,同时间内累计吸渗量较少,吸渗率降低速度更快;(3)短时间负压灌溉条件下,不同土层的累计吸渗量与湿润峰、吸渗率与湿润峰倒数、湿润峰平方与时间均存在明显的线性关系;(4)负压灌溉后距离渗水器上下各15 cm范围内,土壤含水率维持于20%~33%范围内,变异系数均在10%左右;(5)拟合结果表明,Kostiakov与Philip模型能很好地描述 5 k Pa负压灌溉下不同处理的水分吸渗特性,而Horton模型描述黑钙土A、B层较长时间的吸渗效果较差。
[Abstract]:Based on the one-dimensional vertical water absorption test under 5 KPA negative pressure irrigation, the water permeability of two kinds of negative pressure water infiltrators, ceramic soil and polyvinyl formaldehyde-foamed plastic (PVFM), in layer B of calcareous soil, were analyzed, and the cumulative amount of water absorption and the absorption rate were measured. The moisture peak and soil moisture content were used to investigate the applicability of three commonly used soil moisture absorption models and vertical one-dimensional unsaturated soil moisture motion algebraic model to describe the process of negative pressure infiltration. The model parameters under different treatments were further compared. The results showed that there was no significant difference in the accumulative permeation capacity between PVFM water infiltrator and clay percolator under 5 KPA irrigation. The former can effectively replace the latter as a negative pressure percolator.) under the condition of short time negative pressure irrigation, the soil water absorption characteristics of the B layer of the calcareous soil are worse than that of the A layer, and the accumulative amount of water absorption in the same time is less, and the rate of absorption decreases faster. There was an obvious linear relationship between the cumulative infiltration capacity and the wetting peak, the reciprocal of the infiltration rate and the wetting peak, the square of the wetting peak and the time. After negative pressure irrigation, there was a range of 15 cm between the top and the bottom of the percolator, and the soil moisture content was maintained in the range of 20% or 33%. The fitting results showed that the Kostiakov model and Philip model could well describe the water absorption characteristics of different treatments under 5 KPA negative pressure irrigation, while the Horton model was less effective in describing the permeability of calcareous soil AB layer for a long time.
【作者单位】：中国农业科学院农业资源与农业区划研究所;黑龙江八一农垦大学;长江大学生命科学院;
【基金】：国家高技术研究发展计划项目(2013AA102901)资助
【分类号】：S152.7

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