负压灌溉下土壤水氮分布对黄瓜氮素吸收和干物质的影响  

Effects of soil water and nitrogen distribution on nitrogen absorption and dry matter of cucumber under negative pressure irrigation

作　　者：焦玲 武雪萍[2] 李晓秀[1] 李生平[2] 李嘉欣 JIAO Ling;WU Xue-ping;LI Xiao-xiu;LI Sheng-ping;LI Jia-xin(College of Resource Environment and Tourism,Capital Normal University,Beijing 100048;Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081)

机构地区：[1]首都师范大学资源环境与旅游学院,北京100048 [2]中国农业科学院农业资源与农业区划研究所,北京100081

出　　处：《中国土壤与肥料》2022年第9期75-84,共10页Soil and Fertilizer Sciences in China

基　　金：国家重点研发计划项目(2018YFE0112300)。

摘　　要：负压灌溉是一种新型地下渗灌技术,能有效提高作物产量、水分和氮肥利用效率。然而,负压灌溉高效增产的机制尚不明确。因此,试验采用基于“作物主动汲水(Crop initiate drawing water)”原理的负压灌溉系统,探讨了不同供水处理对土壤水氮时空分布特征及其对黄瓜氮素吸收和干物质量的影响。采用盆栽试验,以常规浇灌处理为对照(CK),观测4个供水负压(W1,0 kPa;W2,-5 kPa;W3,-10 kPa;W4,-15 kPa)下黄瓜生育期内土壤水分和氮素的分布特征、黄瓜氮素养分吸收利用、干物质量分布、黄瓜产量和氮素利用效率。结果表明,负压灌溉下黄瓜生育期内土壤水分分布较稳定,盆内土壤水分分布均匀系数比常规浇灌提高了28.00%~59.68%。各供水处理土壤硝态氮收获期比初果期增加40.60%~161.15%。土壤硝态氮在CK处理下随着土层深度的增加而增加,但在负压灌溉处理下0~7和14~21 cm土层的土壤硝态氮含量显著高于7~14 cm土层(P<0.05)。与CK处理相比,负压灌溉能显著降低14~21 cm土层土壤硝态氮含量,表明负压灌溉有助于降低土壤硝态氮的淋溶风险。负压灌溉能显著提高土壤垂直剖面硝态氮分布均匀性,且该分布均匀性在负压灌溉系统不同供水处理间差异不显著。土壤水氮分布均匀系数与黄瓜累积氮吸收量、产量和氮肥利用效率呈正相关关系,相比CK处理,W2和W3处理显著增加了黄瓜氮吸收量、干物质量和产量,提高了氮肥利用效率。综上所述,与传统灌溉相比,尽管负压灌溉各处理均能显著提高土壤水氮分布均匀性,但是过高或过低的供水负压均可能产生水分胁迫,不利于作物生长发育和产量的形成。Negative pressure irrigation is a new type of underground infiltration irrigation technology,which can effectively improve crop yield,water and nitrogen utilization efficiency,while the mechanism is still unclear.This study aimed to explore the effect of crop actively drawing water property of negative pressure irrigation for achieving efficient and high yield through the distribution characteristics of soil water and nitrogen and its effect on cucumber growth and yield.The experiment consisted of five water supply treatment:negative pressure treatment W1,0 kPa;W2,-5 kPa;W3,-10 kPa;W4,-15 kPa and conventional irrigation treatment CK.Soil vertical profile water and nitrogen distribution content during the whole growth period were investigated,the soil water and nitrogen distribution uniformity coefficient was calculated,and the effect of soil water and nitrogen distribution uniformity coefficient on cucumber nitrogen absorption,dry matter distribution,yield and nitrogen use efficiency were analyzed.The result showed that under negative pressure irrigation,the fluctuation of soil water in cucumber growth period was small,the soil water space distribution was uniform,with the uniformity coefficient of 28.00%~59.68%higher than that under conventional irrigation.With the increase of the growth period,soil nitrate accumulation was obvious.The soil nitrate accumulation in the whole soil profile increased by 40.60%~161.15%in the harvest period compared with the first fruit stage for each water supply treatment.The distribution uniformity coefficient of soil nitrate nitrogen under negative pressure irrigation was significantly higher than that under conventional irrigation,compared to CK treatment,negative pressure irrigation reduced the nitrate nitrogen content in the 14~21 cm soil layer,which helps to reduce the possibility of soil nitrate nitrogen leaching downward.The soil water and nitrogen distribution uniformity coefficient was positively correlated with the cumulative nitrogen uptake,yield and nitrogen use efficie

关 键 词：负压灌溉 水肥一体化 水氮分布均匀系数 黄瓜 氮素吸收 干物质量 

分 类 号：S642.2[农业科学—蔬菜学]