施氮对还田秸秆腐解及养分释放、土壤肥力与玉米产量的影响  

Effects of nitrogen application on decomposition and nutrient release of returning straw,soil fertility,and maize yield

作　　者：李荣[1] 勉有明 侯贤清[1] 李培富[1] 王西娜[1] LI Rong;MIAN You-Ming;HOU Xian-Qing;LI Pei-Fu;WANG Xi-Na(School of Agriculture,Ningxia University,Yinchuan 750021,Ningxia,China;Guyuan Branch of Ningxia Academy of Agriculture and Forestry Sciences,Guyuan 756000,Ningxia,China)

机构地区：[1]宁夏大学农学院,宁夏银川750021 [2]宁夏农林科学院固原分院,宁夏固原756000

出　　处：《作物学报》2023年第7期2012-2022,共11页Acta Agronomica Sinica

基　　金：宁夏自然科学基金项目(2021AAC03003,2022AAC03061);国家自然科学基金项目(31860362,32160515);国家科技支撑计划项目(2015BAD22B05-03)资助。

摘　　要：基于2年秸秆还田定位试验,为了解析宁夏扬黄灌区连续施氮对第3年还田后秸秆腐解及养分释放、土壤肥力特征与玉米产量的影响,采用尼龙网袋法和大田试验相结合的方法,研究连续施用不同纯氮量(0、150、300和450 kg hm^(-2))对第3年还田后秸秆腐解、养分释放和土壤理化性质及玉米产量的影响。结果表明,施氮可在玉米播后50~170d促进秸秆腐解,以施氮300kghm^(-2)处理最为显著,平均秸秆累积腐解率与腐解速率分别较不施氮肥(对照)处理提高25.6%和20.3%;施氮可促进秸秆养分释放,其各养分元素释放率均表现为钾>碳>氮>磷,且均随施氮量的增加呈先增加后降低,以施氮300 kg hm^(-2)处理效果最佳。施氮可使0~40 cm层土壤容重降低,总孔隙度增加,以施氮300~450kghm^(-2)处理效果最为显著;施氮可提高玉米播后20d土壤温度和播后80~170d土壤贮水量,均以施氮300 kg hm^(-2)处理效果最佳。施氮可改善0~40 cm层土壤肥力,以施氮300 kg hm^(-2)处理对提高土壤有机碳、全氮、碱解氮、有效磷和速效钾含量效果最佳。施氮300kghm^(-2)处理能通过影响产量构成来提高玉米产量,较对照增产63.7%。综合分析认为,施氮300 kg hm^(-2)可显著改善土壤肥力特征,促进还田秸秆的腐解和养分元素的释放,从而有利于宁夏扬黄灌区土壤培肥和玉米产量的提高。Based on the two-year located straw returning experiment,to explore the effects of continuous nitrogen application on the decomposition and nutrient release of returning straw in the third year,soil fertility characteristics and maize yield in Yanghuang irrigation area of Ningxia,the effects of continual application rates of different pure nitrogen(0,150,300,and 450 kg hm^(-2))on decomposition,nutrient release of returning straw in the third year,soil physical and chemical properties,and maize yield were studied by nylon mesh bag method and field experiment.The results showed that nitrogen application could promote straw decomposition at 50–170 DAS(days after maize sowing),and the nitrogen application rate at 300 kg hm^(-2) was the best.The cumulative decomposition ratio and decomposition rate of straw under nitrogen application rate at 300 kg hm^(-2) compared with that no nitrogen application treatment(the control),were significantly increased by 25.6%and 20.3%,respectively.Nitrogen application could promote the nutrient release of straw,and the cumulative nutrient release rates of returning straw was ranked:potassium>carbon>nitrogen>phosphorus.The cumulative release rate of each element in all treatments increased first and then decreased with the increase of nitrogen application rate,and the effect of nitrogen application rate at 300 kg hm^(-2) was the best.Nitrogen application made the soil bulk density in 0–40 cm layer decrease,while the soil total porosity increased,and nitrogen application rate at 300–450 kg hm^(-2) was the most significant.Nitrogen application could increase the soil temperature at 20 DAS and soil water storage at 80–170 DAS,and the effect of the nitrogen application rate at 300 kg hm^(-2) was the best.Nitrogen application could improve soil fertility in 0–40 cm layer,and nitrogen application rate at 300 kg hm^(-2) had the best effect on increasing soil organic carbon,total nitrogen,alkali-hydrolyzed nitrogen,available phosphorus,and available potassium contents.Compared with th

关 键 词：施氮 秸秆腐解 养分释放 土壤肥力 玉米产量 

分 类 号：S513[农业科学—作物学] S158