土地整理工程对丘陵山区土壤持水特性的影响  

The Influence of Land Consolidation Project on Soil Water Holding Capacity in the Hilly Area

作　　者：钟茫[1] 任镇江[1] 刘涓[1] 黄晶晶[1] 魏朝富[1] 

机构地区：[1]农业部西南耕地保育重点实验室/西南大学资源环境学院,重庆400716

出　　处：《湖北农业科学》2014年第6期1271-1276,共6页Hubei Agricultural Sciences

基　　金：国家科技支撑计划项目(2012BAD05B06)

摘　　要：通过测定土地整理前后Ⅰ区（由水田改成的旱地）、Ⅱ区（平缓旱地）和Ⅲ区（坡度较大区的旱地）土壤水分特征曲线,计算了比水容量,探讨了水分含量与土壤颗粒之间的关系.结果表明,①土地整理后,土壤水力参数残余含水量（θr）、饱和含水量（θs）、进气吸力的倒数（α）、孔隙大小分布指数（n）在不同质地间的大小排序略有差异,表现出θr基本不受地质影响,而θs、α和n则大致符合质地越粗值越大的规律;②土壤比水容量在低土壤水势段较高,随着土壤水势的增加水分含量明显降低直到基本不变;③在低压力段.土壤容重显著影响土壤的持水性,二者呈极显著正相关,0.020～0.050 mm沙粒和黏粒含量与土壤水分含量呈负相关.其他粒径土壤含量与土壤水分含量呈正相关,但相关性均不显著,田间持水性主要受土壤容重的影响;随着压力的增大土壤水分含量与粉粒含量的正相关性增强,与土壤容重的正相关性减弱.土地整理显著改变土壤的持水性能,影响程度的大小与土地整理工程的扰动程度密切相关.Based on determing of soil water capacity curve in Ⅰ （reclaim paddy to dryland）,Ⅱ （traditional gentle dryland） and Ⅲ （traditional steep dryland）,fitted by Van Genuchten equation and calculated the water unit weight,the relationship between the moisture content and soil particle was studied.The results showed that after arrangement,Hydraulic parameter of soil θr、θs、α、n had slight differences in sorting of different soil texture.θr was not received by soil texture.The lighter soil texture was,the lighter θs、α and n value would be.The water capacity curve showed that the soil in low pressure section had high moisture content.With increasing of pressure,the moisture content decreased.The trend of pressure change would decrease until basically unchanged.It was the same as the trend of moisture content.Analysis of water holding capacity and physical property showed that in low pressure section,the relativity between particle and water unit weight was distinctively positive,and the relativity between 0.020～0.050 mm sand and cosmid was negative.Because of the water holding capacity influenced by water unit weight,the relativity between 0.020～0.250 mm sand and moisture content was not obviously.With the increasing of pressure,the positive correlation between the moisture content and particle enhances.The positive correlation between moisture content and water unit weight was weak.The land consolidation could obviously improve the soil ability of water holding capacity closely related with detail steps.

关 键 词：土地整理工程 土壤持水特性 VAN GENUCHTEN模型 

分 类 号：S15[农业科学—土壤学]