容重对土壤水氮垂直运移特性的影响  

Effects of soil bulk density on vertical migration of soil water and nitrogen

作　　者：刘乐 费良军[1] 曾健 陈琳[1] 傅渝亮[1] 钟韵[1] LIU Le;FEI Liangjun;ZENG Jian;CHEN Lin;FU Yuliang;ZHONG Yun(Institute of Water Resources,Xi′an University of Technology,Xi′an,Shaanxi 710048,China)

机构地区：[1]西安理工大学水资源研究所

出　　处：《排灌机械工程学报》2020年第2期200-205,共6页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家973计划项目(2016YFC0400204);国家自然科学基金资助项目(51479161,51779205)

摘　　要：为研究不同土壤容重下红壤土与黄土中水分与硝态氮垂直一维入渗运移特性差异,提高红壤与黄土地区水肥利用效率,以江西壤黏土与西安粉壤土为研究对象,采用垂直一维入渗方式模拟土壤容重对2种土壤中水分及硝态氮垂直运动规律的影响.结果表明:江西壤黏土与西安粉壤土的湿润锋运移距离及入渗速度均与土壤容重呈负相关;灌水结束时与再分布1 d后,2种土壤的含水率均与土壤容重呈负相关,西安粉壤土的含水率略大于江西壤黏土;土壤容重越大,硝态氮越集中于深层土壤中且其峰值越高,再分布过程中峰值下降,其中容重为1.25,1.35,1.40 g/cm 3的峰值下降较大.灌水结束时土壤容重对40~50 cm土层内的硝态氮质量比在0.05水平下均具有统计学意义;再分布1 d后,2种土壤在0~30 cm土层内的硝态氮质量比相差甚小,在30~60 cm土层内的硝态氮质量比均较高,但西安粉壤土的硝态氮质量比更高.故江西壤黏土中硝态氮更容易淋溶,而西安粉壤土的持水持肥性较好.To study the difference of vertical one-dimensional infiltration migration characteristics of soil water and nitrate-nitrogen in red soil and loess under various soil bulk densities,and to improve the water and fertilizer utilization efficiency in red soil and loess area,the Jiangxi loam clay and the Xi′an silty loam were taken as the study objects.The vertical one-dimensional infiltration mode was used to simulate the effect of soil bulk density on the vertical migration of water and nitrate-nitrogen in the two soils.The results show that the wetting front migration distance and infiltration rate of the Jiangxi loam clay and the Xi′an silty loam are both negatively correlated with soil bulk density.Whether at the end of irrigation or after the redistribution of 1 day,the moisture content of the two soils is negatively correlated with soil bulk density,and the moisture content of the Xi′an silty loam is slightly larger than that of the Jiangxi loam clay.The greater the soil bulk density is,the more the nitrate-nitrogen is concentrated in the deep soil and the higher its peak value.In the redistribution process,the peak value decreases,and that of the bulk density of 1.25,1.35 and 1.40 g/cm 3 decreases greatly.At the end of irrigation,soil bulk density has a significant effect on the nitrate-nitrogen concentration in the 40-50 cm soil layer(P<0.05).After the redistribution of 1 day,there is little difference between the concentration of nitrate-nitrogen in 0-30 cm soil layer of the two soils,the concentration of nitrate-nitrogen in 30-60 cm soil layer is higher,but the concentration of nitrate-nitrogen in Xi′an silty loam soil is higher.Therefore,the nitrate-nitrogen of the Jiangxi loam clay is more easily leached,while soil moisture and fertility retention properties of the Xi′an silty loam are better.

关 键 词：硝态氮 含水率 江西壤黏土 西安粉壤土 土壤容重 

分 类 号：S271[农业科学—农业水土工程]