不同控水下限对设施青梗菜田残留氮分布及再利用的影响  

Effects of Different Lower Water Control Limits on the Distribution and Reuse of Residual Nitrogen in Greenstem Vegetable Fields Under Facilities

作　　者：章二子 翟亚明[2] 钟凤林[3] 侯毛毛[3] ZHANG Er-zi;ZHAI Ya-ming;ZHONG Feng-lin;HOU Mao-mao(Jiangning District Water Affairs Bureau of Nanjing City,Nanjing 210000,China;College of Agricultural Science and Engineering,Hohai University,Nanjing 210098,China;College of Horticulture,Fujian Agriculture and Forest University,Fuzhou 350002,China)

机构地区：[1]南京市江宁区水务局,南京210000 [2]河海大学农业科学与工程学院,南京210098 [3]福建农林大学园艺学院,福州350002

出　　处：《节水灌溉》2024年第1期109-114,127,共7页Water Saving Irrigation

基　　金：福建省自然科学基金项目“水分调控对设施菜地土壤残留氮迁移转化及再利用的影响机制”(2023J01133579)。

摘　　要：设施栽培氮肥投入大、残留高,过量氮肥残留导致土壤环境恶化,然而,残留氮也是重要的土壤氮素资源。为研究不同水分调控方案对土壤残留氮分布和再利用的影响,采用15N同位素标记技术,种植2茬青梗菜,首茬青梗菜设N1、N2、N3共3种施氮水平,分别为150、225、300 kg/hm^(2)的(^(15)NH_(2)CO_(2)^(15)NH_(2)),二茬青梗菜设W1、W2、W3共3种水分下限方案(占田间持水量的百分数),分别为60%、70%和80%,观测不同处理下残留氮的分布、再利用和平衡规律。研究结果表明:N1-N3处理共有72.3、123.6和195.3 kg/hm^(2)的氮肥残留于0~60 cm土体中,主要以矿质态存在。在N1、N2和N3共3种残留氮场景下,均以W2处理根系鲜重最大,分别达到0.182、0.188和0.195 g/株。不同处理以W2N1处理青梗菜残留氮利用效率最高,达到5.4%。在相同土壤氮残留量条件下,W2处理残留氮利用效率显著(p<0.05)高于W1和W3。前茬施氮量越高,残留氮肥在后茬栽培过程中的损失风险越大;控水下限越高,残留氮更易向40 cm以下土层迁移,总损失量也越大,与W1相比,W3处理残留氮损失量增加了29.9%~66.7%(2.29~6.97kg/hm^(2))。推荐70%控水下限作为提升残留氮利用效率的最优水分调控方案。Facility cultivation requires high input of nitrogen fertilizer,which can lead to excess residue and soil degradation.However,residual nitrogen is also an important soil nitrogen resource.To study the effects of different water regulation schemes on soil residual nitrogen reuse and distribution,this study used 15N isotope labeling technology to plant two crops of green stem vegetables.The first crop of green stem vegetables was treated with three nitrogen application levels(N1:150 kg/hm^(2),N2:225 kg/hm^(2),300 kg/hm^(2),N_(3):^(15)NH_(2)CO_(2)^(15)NH_(2)),and the second crop of green stem vegetables was treated with three lower water limits schemes(accounting for W1:60%,W2:70%,and W3:80%of the field water capacity)to observe the distribution,reuse,and balance of residual nitrogen under different treatments.The research results indicate that a total of 72.3,123.6,and 195.3 kg/hm^(2) of nitrogen fertilizer remained in the 0~60 cm soil under N1-N3 treatment,mainly in the mineral form.When examining the residual nitrogen scenarios of N1,N2,and N3,it was observed that the W2 treatment had the highest fresh root weight,with values of 0.182,0.188,and 0.195 g/plant,respectively.The W2N1 treatment obtains the highest residual nitrogen utilization efficiency,reaching 5.4%,among different treatments.Under the same soil nitrogen residue conditions,the residual nitrogen utilization efficiency of W2 treatment was significantly higher(p<0.05)than that of W1 and W3.The higher the nitrogen application rate in the previous crop caused the greater the risk of residual nitrogen fertilizer loss during the subsequent crop cultivation process.The higher the lower limit of water control,the easier residual nitrogen is to migrate to the soil layer below 40 cm,leading to the greater the loss.Compared with W1,the loss of residual nitrogen in W3 treatment was increased by 22.9%~40.0%(2.29~6.97 kg/hm^(2)).In summary,this study recommends a 70%lower limit of water control as the optimal water regulation scheme to improve residual nitrogen ut

关 键 词：灌水下限 施氮量 残留氮分布 残留氮再利用 水分调控 青梗菜 

分 类 号：S274[农业科学—农业水土工程]