蓄水坑灌体系温度对土壤氮素运移转化影响  

The Spatial Distribution Characteristics,Transportation and Transformation Mechanism of Soil Moisture as Well as Nitrogen in Different Temperature Conditions Under Water Storage Pit Irrigation

作　　者：史晓凯[1,2] 马娟娟[1] 冯晓波[1] 郑利剑 孙西欢[1,3] SHI Xiao-kai MA Juan-juan FENG Xiao-bo ZHENG Li-jian SUN Xi-huan(College of Water Conservancy Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China Shanxi Academy of Environmental Sciences, Taiynan 030027, China Shanxi Conservancy Technical College, Yuneheng 044004, Shanxi Province, China)

机构地区：[1]太原理工大学水利科学与工程学院,太原030024 [2]山西省环境科学研究院,太原030027 [3]山西水利职业技术学院,山西运城044004

出　　处：《节水灌溉》2017年第2期48-53,57,共7页Water Saving Irrigation

基　　金：国家自然科学基金项目(51109154;51249002);教育部博士点基金项目(20111402120006;20121402110009);山西省青年科技研究基金项目(2012021026-2);山西省科技攻关项目(20110311018-1;20140311016-6)

摘　　要：通过研究体系温度对蓄水坑灌施条件下土壤水分及氮素运移转化的影响,明确蓄水坑灌土壤水氮时空分布特征,探究土壤水氮运移迁移转化机理,以期为水肥合理灌施提供理论基础。通过模拟构建蓄水坑灌模型,以大型控温箱精确控制土壤温度,采用克里克空间插值法分析了蓄水坑灌条件不同体系温度下的水分、硝态氮、铵态氮时空分布特征,结果显示7 h左右土壤水分、养分完成入渗进入再分布阶段,土壤水分随着时间的推移其垂向和径向迁移距离均逐渐增大,同一时刻,温度越高其横向与径向迁移距离越大,且靠近蓄水坑壁区域的土壤含水率相对越低;土壤中铵态氮含量在不同温度下随时间推移均呈现先增后减的现象,低温下第15 d时土壤养分再分布核心区出现下降趋势,中、高温第10 d时已出现下降趋势,且其迁移距离远低于水分、硝态氮的迁移距离;土壤中硝态氮含量在10℃下第10 d时出现增高现象,而20、25、35℃下第5 d时已出现增高现象,由蓄水坑周边至湿润体边缘呈现"低-高-低"的分布态势。表明再分布阶段温度升高能提高水分的再分布速率,提高脲酶活性加快尿素水解转化为铵态氮,同时促进硝化反应进程抑制铵态氮在土壤中的积累,当土壤含水量过高时,会抑制土壤中氮素的硝化作用。Accurate description of the soil moisture and nitrogen transport and transformation is of great importance to establish an appropriate irrigation and fertilization scheme. In order to explore the spatial and temporal distribution characteristics, transportation and transformation mechanism of soil moisture as well as nitrogen in different system temperature conditions under water storage pit irrigation, a simulation model through controlling the soil temperature with the help of temperature control boxes was constructed and the Crick spatial interpolation method was applied to plot soil water content, nitrate and ammonium nitrogen contour maps under different time and system temperature conditions. The research results show that soil moisture and nutrient infiltration process were completed and redistribution was begun after about 7 hours ; with time going on, both the vertical and horizontal distance of water in the soil would increase ; at the same moment, with the temperature rising, the vertical and horizontal distance continued increasing, and soil moisture was relatively low near the part of water storage pit wall area ; the content of ammonium nitrogen in the soil was rising first and then declining under different temperatures ; under low temperatures, the fertilizer redistribution in the soil began to decline on the 15 th day, while for the middle and high temperatures, it began to decline on the 10th day and the migration distance was much smaller than the migration distance of water and nitrate nitrogen ; the content of nitrate nitrogen began to increase under ten degrees Celsius on the 10th day; while under twenty, twenty-five and thirty-five degrees Celsius, it began to rise on the 5th day. What＇s more, the content of nitrate nitrogen distributed near water storage pit and soil wetting pattern was curvilinear which was from low to high then to low. All of these indicated that during the redistribution period, along with the temperature rising, the velocity of water redistribution would also increas

关 键 词：蓄水坑灌 体系温度 氮素运移转化 时空分布 

分 类 号：S275[农业科学—农业水土工程] TV121.1[农业科学—农业工程]