水耕年限对麦季土壤水-氮动态与小麦产量的影响  

Effects of Paddy Rice Cultivation History on Water and Nitrogen Dynamics During Wheat Growth Period and Wheat Yield

作　　者：段赫 刘目兴 张海林[1,2] 刘秀芸 张君[1] 易军 DUAN He;LIU Muxing;ZHANG Hailin;LIU Xiuyun;ZHANG Jun;YI Jun(Key Laboratory for Geographical Process Analysis&Simulation,Hubei Province,Wuhan 430079;College of Urban and Environmental Sciences,Central China Normal University,Wuhan 430079)

机构地区：[1]地理过程分析与模拟湖北省重点实验室,武汉430079 [2]华中师范大学可持续研究中心,武汉430079

出　　处：《水土保持学报》2020年第6期259-264,274,共7页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(41601215,41771261);湖北省自然科学基金项目(2019CFB766,2016CFA027);华中师范大学中央高校基本科研业务费项目(CCNU19TS005)。

摘　　要：为揭示水耕年限对小麦生产的影响,在江汉平原选取了3种水耕年限(2年、18年、>100年)稻-麦轮作农田,采集了小麦各生育期的土壤样品与成熟期的小麦植株样品,测定了土壤水分、硝态氮含量、铵态氮含量和小麦产量等指标,分析了土壤剖面水-氮动态分布与积累特征,及其对小麦产量的影响程度与机制。结果表明:(1)随水耕年限延长,土壤水分和氮素含量显著增加。水耕2年、18年和100年农田的0-100 cm深度剖面平均体积含水量分别为0.36,0.39,0.42 cm^3/cm^3。硝态氮和铵态氮在0-20 cm土层富集,水耕2年、18年和100年农田0-20 cm土层硝态氮含量分别为12.26,12.74,14.88 mg/kg,铵态氮含量分别为6.01,8.33,11.69 mg/kg。(2)小麦产量随着水耕年限的增加而降低,水耕2年、18年和100年农田小麦产量分别为4068,3080,2469 kg/hm 2,主要表现为降低小麦的有效穗数和单株穗粒数。(3)长年耕作稻田形成的犁底层造成耕作层土壤水分滞留,进而导致小麦产量降低,而氮素含量差异未显著影响小麦产量,需要通过改善农田排水状况以降低长水耕年限农田的小麦渍害风险。In order to identify the effects of paddy rice cultivation history on wheat production,three rice-wheat rotation fields with different paddy rice cultivation years(2 years,18 years,and>100 years)were selected for study in the Jianghan Plain.Soil samples and wheat plants were collected in different wheat growth periods to measure the moisture,nitrate nitrogen(NO 3^--N)and ammonium nitrogen(NH 4^+-N)contents in soils,and even the wheat yield.The results showed as follow:(1)With the increase of paddy rice cultivation years,soil moisture,NO 3^--N and NH 4^+-N contents increased significantly.The highest average soil water content was observed in the>100 years field(0.42 cm^3/cm^3),followed by the 18 years field(0.39 cm^3/cm^3)and the 2 years field(0.36 cm^3/cm^3).NO 3^--N and NH 4^+-N were enriched in the 0-20 cm soil layer,and the average NO 3^--N content and NH 4^+-N content in this soil layer was 12.26 and 6.01 mg/kg,12.74 and 8.33 mg/kg,and 14.88 and 11.69 mg/kg for the 2 years,18 years,and>100 years paddy fields,respectively.(2)The wheat yields decreased with the extending paddy rice cultivation years,which was 4068,3080 and 2469 kg/hm 2 for the 2 years,18 years,and>100 years paddy rice fields,respectively,and were characterized by the decreasing of number of available tillers and ears per plant.(3)Water logging in the plough layer was the main reason for the reduced wheat yield,rather than the differences in nitrogen content.It is necessary to enhance soil water drainage rate to reduce the risk of water logging on wheat growth in the fields with long paddy rice cultivation years.

关 键 词：土壤含水量 硝态氮 铵态氮 小麦 江汉平原 

分 类 号：S152[农业科学—土壤学] S512.1[农业科学—农业基础科学]