摘要
针对水氮耦合的常规滴灌导致设施菜地氮素淋失比较严重的现状,提出水氮部分解耦滴灌方法(解耦滴灌),并在水多氮少(水多)根区土壤和水少氮多(水少)根区土壤滴灌位点距离、灌溉量比和施氮量比分别为15 cm、2和0.67的情况下验证其削减粉壤(深度28 cm)氮素淋失效果。结果表明:常规滴灌改成解耦滴灌,无植物影响、日均灌溉强度12.8 mm的条件下,土壤氮素淋失削减幅度小(<10%);密植黄瓜(株距25 cm)存在、日均灌溉强度22.2 mm的条件下,水分淋失平均仅降低10.8%,淋失液中硝态氮平均占比82.0%的水溶氮的浓度平均降低35.6%(P<0.05),氮素淋失显著降低42.8%(P<0.05),土壤硝态氮残留增加显著,黄瓜增产16.1%(P<0.05);解耦滴灌促进黄瓜从水多根区土壤多吸收水分,弱化水分和硝态氮在土壤中方向相反的横向扩散,降低主要来自于水多根区土壤的淋失液的水溶性氮浓度,水分淋失量变化不大情况下实现土壤氮素淋失削减。
Water⁃nitrogen partially decoupled drip fertigation(DF)was proposed to cut nitrate leaching loss often associated with conventional water⁃nitrogen coupled drip fertigation(CF)in greenhouse soils.To investigate the performance of DF in a silty loam soil(thickness 28 cm),the distance between drip irrigation loci,the relative ra⁃tio of irrigation or nitrogen fertilization on water⁃more⁃nitrogen⁃less(WM)and water⁃less⁃nitrogen⁃more(WL)root⁃zone soil were set at 15 cm,2,and 0.67,respectively.The reduction in soil nitrogen leaching without the presence of plants was small at an average daily irrigation intensity of 12.8 mm(<10%)after a switch from CF to DF.With an average daily irrigation intensity of 22.2 mm and the presence of densely planted cucumbers(plant spacing 25 cm),such switch slightly reduced water leaching intensity(10.8%)but significantly reduced the content of ni⁃trate⁃dominated(averagely 82.0%)dissolved nitrogen in leachate averagely by 35.6%(P<0.05),resulting in sig⁃nificant reduction in dissolved nitrogen leaching by 42.8%(P<0.05),significant increases in soil residual nitrate level and cucumber yield(16.1%;P<0.05).DF promoted water absorption from the WM rootzone soil to weaken the lateral diffusion of water and nitrate in opposite direction in soil,and subsequently reduced dissolved nitrogen content in leachate mainly derived from the WM rootzone soil to reduce the leaching loss of dissolved nitrogen with⁃out much change in water leaching.
作者
牛明芬
贺敬
马建
全智
迟光宇
鲁彩艳
黄斌
NIU Mingfen;HE Jing;MA Jian;QUAN Zhi;CHI Guangyu;LU Caiyan;HUANG Bin(College of Municipal and Environmental Engineering,Shenyang Jianzhu University,Shenyang 110168,China;Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China;Weifang Academy of Modern Agriculture and Ecological Environment,Weifang 261041,Shandong,China)
出处
《生态学杂志》
北大核心
2025年第7期2229-2239,共11页
Chinese Journal of Ecology
基金
国家自然科学基金项目(U2106214)
国家重点研发计划项目(2017YFD0800402)
山东省自然科学基金优秀青年基金(ZR2023YQ0301)
山东省泰山学者青年专家项目(202211306)资助。
关键词
根区土壤
横向扩散
硝态氮
rootzone soil
lateral diffusion
nitrate
