颗粒级配变化对黄三角盐碱土水分特征曲线参数的影响以VG模型和Gardner模型为例  

Effect of Particle Gradation on Water Characteristic Curve Parameters of Yellow Triangle Saline Alkali Soil:A Case Study of VG Model and Gardner Model

作　　者：郭同铠 毛伟兵[1] 孙玉霞[1] 孙池涛 贾文慧 GUO Tong-kai;MAO Wei-bing;SUN Yu-xia;SUN Chi-tao;JIA Wen-hui(College of Water Conservancy and Civil Engineering,Shandong Agricultural University,Tai'an 271018,Shandong Province,China)

机构地区：[1]山东农业大学水利土木工程学院,山东泰安271018

出　　处：《节水灌溉》2020年第1期29-33,共5页Water Saving Irrigation

基　　金：山东省重大科技创新项目“盐渍土快速改良与地力培肥产品的研发与应用”(2017CXGC0306)。

摘　　要：为研究颗粒级配变化对黄河三角洲盐碱土壤水分特征曲线方程参数的影响,进行了不同配沙量下的室内模拟试验,通过压力膜法测定了各处理不同水吸力下的土壤含水量,结合VG模型和Gardner模型,分析了两个模型对土壤水分特征曲线的适用性,以及土壤颗粒级配变化对模型参数的影响。结果表明:盐碱土配沙后,土壤颗粒组成发生明显变化。其中,0.05~0.1 mm的颗粒相对含量从3.6%增加到62.02%,<0.002 mm的颗粒相对含量从29.02%降低到3.89%,土壤颗粒级配发生明显改变;盐碱土配沙量较高(67.0%)的条件下,参数n随配沙量的增加呈增加趋势,α值随配沙量的增加呈降低趋势。Gardner模型中参数a仅与某段配沙量(28.8%~45.2%)处理呈线性负相关,参数b随配沙量的增加整体呈先增加再降低的趋势。VG模型与Gardner模型均可拟合黏质盐土不同配沙量条件下土壤水分特征曲线,VG模型对土壤水分特征曲线拟合度优于Gardner模型,但VG模型模拟精度低于Gardner模型。For the study of particle size distribution change on the Yellow River delta saline soil water characteristic curve equation parameters,laboratory simulation experiments were carried out under different sand distribution.The soil moisture content under different water suction of each treatment was measured by pressure film method.Combined with VG model and Gardner model,the applicability of the two models to the soil water characteristic curve was analyzed,as well as the influence of the change of soil particle gradation on the model parameters.The results showed that the composition of soil particles changed obviously after saline-alkali soil mixed with sand.Among them,the relative content of 0.05~0.1 mm particles increased from 3.6%to 62.02%,and the relative content of particles less than 0.002 mm decreased from 29.02%to 3.89%,indicating significant changes in soil particle gradation.Under the condition that the saline-alkali soil had a high amount of sand distribution(67.0%),the parameter n showed an increasing trend with the increase of the amount of sand distribution,while the ordinal value showed a decreasing trend with the increase of the amount of sand distribution.In the Gardner model,parameter a was only negatively correlated linearly with the treatment of sand allocation in a certain section(28.8%~45.2%),while parameter b showed an overall trend of first increasing and then decreasing with the increase of sand allocation.Both VG model and Gardner model can fit the soil water characteristic curve of clay saline soil with different sand distribution.The fitting degree of VG model to soil water characteristic curve was better than that of Gardner model,but the simulation accuracy of VG model was lower than that of Gardner model.

关 键 词：盐碱土 土壤水分特征曲线 模型 黄河三角洲 

分 类 号：S156.42[农业科学—土壤学]