河西走廊荒漠绿洲农田氮素吸收、残留与淋失特征  

Nitrogen uptake,surplus,and leaching in desert oasis fields in the Hexi Corridor in northwestern China

作　　者：王丽莎 陈龙飞 罗德伟 何志斌 何晓丽 WANG Lisha;CHEN Longfei;LUO Dewei;HE Zhibin;HE Xiaoli(College of Resource Environment and Tourism,Hubei University of Arts and Science,Xiangyang 441053,China;Linze Inland River Basin Research Station,CAS Key Laboratory of Ecohydrology of Inland River Basin,Northwest Institute of EcoEnvironment and Resource,Chinese Academy of Sciences,Lanzhou 730000,China;Xiangyang Ecological Environment Monitoring Center,Department of Ecology and Environment of Hubei Province,Xiangyang 441000,China)

机构地区：[1]湖北文理学院资源环境与旅游学院,襄阳441053 [2]中国科学院西北生态环境资源研究院临泽内陆河流域综合研究站,中国科学院内陆河流域生态水文重点实验室,兰州730000 [3]湖北省生态环境厅襄阳生态环境监测中心,襄阳441000

出　　处：《应用与环境生物学报》2024年第6期1115-1123,共9页Chinese Journal of Applied and Environmental Biology

基　　金：第二次青藏高原综合科学考察研究项目(2019QZKK0303);湖北省自然科学基金项目(2022CFB783)资助。

摘　　要：灌溉和施肥是保障干旱区绿洲农业高产的关键,由此导致荒漠绿洲农业区农业面源污染愈发严重.绿洲区农田耕作年限不同,土壤熟化程度各异,土壤质地异质性明显,导致不同开垦年限农田系统氮素吸收和利用效率差异明显.通过土柱模拟试验,定量研究连续开垦24年的新绿洲农田(砂壤土)和连续开垦56年的老绿洲农田(粉壤土)玉米生物量、氮素吸收、土壤累积氮、氮淋溶和氮肥利用效率变化特征,揭示不同开垦年限农田氮素回收、残留与淋失特征.结果显示,灌溉后,土壤溶液硝态氮(NO_(3)^(-)-N)浓度在表层迅速增加,后缓慢下降,在深层稳定增加,新绿洲农田土壤溶液NO_(3)^(-)-N浓度比老绿洲农田提前1-2 d到达峰值.老绿洲农田0-200 cm土层土壤NO_(3)^(-)-N净累积量为34.5 kg/hm^(2),显著高于新绿洲农田的17.6 kg/hm^(2)(P<0.01).新绿洲农田深层渗漏水量和NO_(3)^(-)-N淋失量分别比老绿洲农田高2.75和2.06倍(P<0.01).新绿洲农田和老绿洲农田玉米氮素回收量分别为198.2和255.5 kg/hm^(2),分别占氮肥投入总量的60.1%和77.4%,老绿洲农田的氮肥利用效率比新绿洲农田30.5%.本研究表明含沙量高的砂质农田不利于水分和氮的保持,导致新绿洲农田作物产量和氮肥利用效率低下;因此,干旱区砂质农田必须改善土壤结构,以减少农田氮素淋失,提高氮肥利用效率.Irrigation and fertilization are key to ensuring high-yield oasis agriculture in arid areas,which result in a high incidence of non-point-source pollution.Fields with different soil properties give rise to significant differences in nitrogen recovery efficiency,N surplus,and N leaching.In this study,changes in the levels of maize biomass,N uptake,soil NO_(3)^(-)-N accumulation,NO_(3)^(-)-N leaching,and N fertilizer-use efficiency(NFUE)in young oasis field(YOF),which was reclaimed for 24 years,and old oasis field(OOF),which was reclaimed for 56 years,were quantitatively examined using a soil column simulation test.The results showed that following irrigation,the concentration of NO_(3)^(-)-N in the soil solution rose quickly in the top layer,declined gradually in the middle layer,and climbed steadily in the lower layer.In newly reclaimed farmland,the concentration of NO_(3)^(-)-N in the soil solution peaked around two days earlier than in the older oasis farmland.The net NO_(3)^(-)-N accumulation in the 0-200 cm soil layer of OOF was 34.5 kg/hm^(2),which was significantly higher than that in YOF(17.6 kg/hm^(2))(P<0.01).The deep leaching water and NO_(3)^(-)-N leaching loss of YOF were 2.75-and 2.06-times higher than those of OOF,respectively(P<0.01).Maize recovered 198.2 and 255.5 kg/hm^(2)of N in YOF and OOF,respectively,which accounted for 60.1%and 77.4%of the total N input.Compared to YOF,the NFUE of OOF was 30.5%greater.Sandy farmland with a high sand content was not conducive to the retention of water and nitrogen,which led to a low crop yield and NFUE in YOF.These findings indicate that improvements in soil structure are necessary to decrease nitrogen leaching and boost NFUE in dry sandy farmland.

关 键 词：绿洲农田 土柱 硝酸盐淋失 氮素吸收 氮素残留 氮肥利用效率 

分 类 号：S51[农业科学—作物学]