SWAT模拟耕作方式与盐分对区域土壤氮运移及作物产量影响  

Effects of tillage modes and soil salinity on regional nitrate nitrogen transport and crop yields using a SWAT model

作　　者：王维刚 史海滨[1,2] 李仙岳 孙亚楠[1,2] 郑倩 张文聪 王国帅[1,2] 周慧 闫妍 窦旭 Wang Weigang;Shi Haibin;Li Xianyue;Sun Yanan;Zheng Qian;Zhang Wencong;Wang Guoshuai;Zhou Hui;Yan Yan;Dou Xu(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;High Efficiency Water-saving Technology and Equipment and Soil and Water Environment Effect in Engineering Research Center of Inner Mongolia Autonomous Region,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学水利与土木建筑工程学院,呼和浩特010018 [2]高效节水技术装备与水土环境效应内蒙古自治区工程研究中心,呼和浩特010018

出　　处：《农业工程学报》2022年第3期55-65,共11页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(51769024);内蒙古自治区水利科技重大专项(213-03-99-303002-NSK2017-M1)。

摘　　要：耕作方式与土壤盐渍化是影响河套灌区氮素流失及作物产量的重要因素。明确不同耕作方式与盐渍化水平下硝态氮运移量及作物产量的变化,可为制定合理的灌区耕作措施及盐渍化治理方案提供理论依据,对于揭示灌区氮素流失控制及不同作物增产潜力具有重要意义。该研究基于验证后的SWAT(Soil and Water Assessment Tool)模型,以河套灌区2种主要土壤类型为研究对象,设置不耕作(指不添加耕作管理,CK)、免耕(T1)、少耕(T2)、常规春耕(T3)和模板犁(T4)5种耕作处理,非盐化土(S1)、轻度(S2)、中度(S3)、重度(S4)4种盐分水平,研究耕作方式与土壤盐分对灌区产水量、作物吸氮量、硝态氮淋溶量及运移量、作物产量的影响。结果表明:耕作方式与土壤盐分对区域总产水量、作物吸氮量、硝态氮淋溶量、硝态氮运移及作物产量均有显著影响(P<0.05)。其中,区域产水量、硝态氮淋溶量、不同水文路径(地表、侧向和地下径流)硝态氮运移量及小麦产量均随耕作混合深度与混合效率的增加逐渐减少;作物吸氮量、玉米与葵花产量均随耕作混合深度与混合效率的增加逐渐增加。与CK相比,模板犁耕作作物吸氮量平均增加11.78%,硝态氮淋溶量平均减少16.5%,有效降低了土壤养分流失和地下水污染。增加土壤盐分通过降低土壤层有效持水量,显著增加了区域总产水量、硝态氮淋溶量(草甸盐土除外)及硝态氮地下运移量,减少了作物吸氮量和作物产量。与非盐化土相比,重度盐化土处理小麦、玉米、葵花产量平均显著减少19.15%、27.31%、26%(P<0.05)。增加土壤盐分相比转变耕作方式更能影响区域产水量、土壤养分和作物产量。因此,为更好解决灌区污染严重和作物产量下降等问题,仍需将区域土壤盐渍化防控与治理放在首要位置。A Soil and Water Assessment Tool(SWAT)model was selected to simulate the dynamic changes of water and fertilizer migration,and crop yields under different tillage modes and soil salinization levels.The Hetao Irrigation District with the complex spatial variability of soil salinity were taken as the research object,where three areas were divided:Jiefangzha,Yongji,and Yichang irrigation area.Some parameters were utilized for the simulation and verification of the model,including eight runoff and seven nitrate-nitrogen variables.At the same time,five parameters of crop growth were selected using the existing research.Finally,the specific values of each variable were measured at the outlets of irrigation areas.The soil types were also the cumulic anthrosols and mollic solonchaks in the study area.Four salinity levels were set under the two soil types,according to the grades of non-salinized soil(S1),lightly salinized soil(S2),moderately salinized soil(S3),and heavily salinized soil(S4).At the same time,five farming treatments were selected in the long-term farming mode:no-tillage management(CK),no tillage(T1),less tillage(T2),conventional spring tillage(T3),and template plowing(T4).A systematic investigation was then made on the effects of tillage modes and soil salinization on water production,crop nitrogen uptake,nitrate-nitrogen leaching and transportation,as well as the crop yields in the irrigation areas.As such,the salinized soil was be adjusted to reduce environmental pollution,while promoting the grain production,and the sustainable development of agriculture.The results show that the SWAT model with the calibrated parameters performed better than before to directly verify the runoff and nitrate nitrogen,where the determination coefficient R;,and the efficiency coefficient were not less than 0.69 and 0.58,respectively,while the absolute value of the Relative Error(RE)was less than 10%.The simulated and measured crop yields were basically distributed near the 1:1 line,where the efficiency coefficient and R;val

关 键 词：土壤 盐分 氮 SWAT模型 河套灌区 耕作方式 硝态氮运移 作物产量 

分 类 号：S274[农业科学—农业水土工程] S19[农业科学—农业工程]