增温和秸秆还田对黑土农田土壤氮素有效性和N_2O通量的影响  

Effects of warming and straw returning on soil nitrogen availability and nitrous oxide flux in a Mollisol cropland

作　　者：韩林 何朋 张志明[2] 杨雪辰 李禄军 HAN Lin;HE Peng;ZHANG Zhiming;YANG Xuechen;LI Lujun(School of Geographical Sciences and Tourism,Jilin Normal University,Siping 136000,China;Hailun National Observation and Research Station of Agroecosystems,Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Harbin 150081,China)

机构地区：[1]吉林师范大学地理科学与旅游学院,吉林四平136000 [2]中国科学院东北地理与农业生态研究所,海伦农田生态系统国家野外科学观测研究站,黑龙江哈尔滨150081

出　　处：《土壤与作物》2024年第2期154-164,共11页Soils and Crops

基　　金：国家重点研发计划项目(2022YFD1500305);中国科学院东北地理与农业生态研究所青年科学家小组项目(2023QNXZ04);国家自然科学基金项目(32101396,42277350,U23A6001);黑龙江省自然科学基金杰出青年项目(JQ2021C004)。

摘　　要：土壤氮转化速率决定着土壤供氮能力,除受到温度的影响,还受到底物有效性的影响。然而,在农田生态系统中,关于土壤氮素有效性和N_2O通量对气候变暖和秸秆还田耦合的响应研究仍不足。本研究在东北黑土区进行增温和秸秆还田试验,采用离子交换树脂膜和静态暗箱法,原位监测0~20 cm土层土壤铵态氮、硝态氮有效性和氧化亚氮(N_2O)通量,探究增温和秸秆还田对农田黑土氮转化的影响。结果表明:增温、秸秆还田没有显著影响土壤氮有效性,但其在不同时期存在显著差异。秸秆还田显著增加了N_2O通量,且7月增温和秸秆还田处理对N_2O通量具有显著交互作用。在不增温条件下,秸秆还田使N_2O显著提升了109%;在增温条件下,秸秆还田使N_2O显著下降了2%。增温、秸秆还田和取样月份对N_2O通量也具有显著交互作用。研究结果有利于评估全球气候变暖背景下秸秆还田对农田生态系统氮周转的调控作用,对研究黑土氮循环过程具有重要参考价值。Soil nitrogen(N)transformation processes determine the capacity of soil N supply to plant.The soil N transformation rates are affected by temperature and substrate availability.However,we are still far from understanding how soil N availability and nitrous oxide(N2O)flux respond to warming and straw returning.We conducted a field experiment in a Mollisol cropland in North-east China.We measured soil N availability and N2O flux in the 0-20 cm soil layer by using ion exchange resin membrane(IERM)in situ and static chamber-gas chromatography.Our results show that neither warming nor straw returning has significant effect on soil N availability,but the sampling time has a significant effect on soil N availability.Straw returning significantly increases N2O flux;in July,warming and straw returning has a significant interaction on N2O flux.Under the un-warming condition,straw returning significantly increases N2O flux by 109%;but under the warming condition,straw returning reduces N2O flux by 2%.Warming,straw returning,and sampling time has significant interactive effects on N2O flux.Overall,this study helps to evaluate the effect of straw returning on soil N transformation under global warming in cropland ecosystems,which is essential to future research on N cycling in Mollisols.

关 键 词：黑土 全球变暖 氮素有效性 N_2O通量 大豆秸秆 

分 类 号：S155.27[农业科学—土壤学]