夜间增温下施硅对稻田CH_(4)好氧氧化及其氮响应的影响  

Effects of applying silicon on aerobic CH_(4) oxidation in paddy field under nighttime warming and its response to nitrogen

作　　者：周聪 谢晴 薛梦琪 张耀鸿[1] 娄运生[1] 贾仲君[3] 高霄鹏 ZHOU Cong;XIE Qing;XUE Meng-qi;ZHANG Yao-hong;LOU Yun-sheng;JIA Zhong-jun;GAO Xiao-peng(Collaborative Innovation Center for Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science and Technology/Jiangsu Provincial Key Laboratory of Agricultural Meteorology,Nanjing,Jiangsu 210044,China;Hunan Key Laboratory of Meteorological Disaster Prevention and Reduction,Changsha,Hunan 410118,China;State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing,Jiangsu 210008,China;University of Manitoba,Winnipeg,Manitoba R3T2N2,Canada)

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心/江苏省农业气象重点实验室,江苏南京210044 [2]气象防灾减灾湖南省重点实验室,湖南长沙410118 [3]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,江苏南京210008 [4]曼尼托巴大学,加拿大温尼伯R3T2N2

出　　处：《南方农业学报》2022年第8期2133-2141,共9页Journal of Southern Agriculture

基　　金：国家自然科学基金项目(42175138,91751204,41875177);江苏省研究生科研创新计划项目(KYCX22_1222)。

摘　　要：【目的】研究硅肥对增温稻田甲烷(CH_(4))好氧氧化速率的影响效应,为探索未来全球变暖背景下稻田温室气体减排措施提供科学依据。【方法】采用田间开放式增温系统对稻田土壤进行夜间增温,共设4个处理:夜间常温不施硅(CK)、夜间增温不施硅(NW)、夜间常温施硅(Si)和夜间增温施硅(NW+Si)。采集上述处理4年后的耕层根际土和非根际土,在无氮添加和氮添加(NH_(4)^(+)、NO_(3)^(-)和尿素)条件下进行室内培养,采用^(13)CH_(4)标记方法,研究稻田CH_(4)好氧氧化速率和固碳特征及其对氮肥的响应。【结果】Si处理稻田土壤的总有机碳和水溶性有机碳含量分别为23.2 g/kg和216.7 mg/kg,较CK稻田提高10.5%和26.7%;而NW处理的总有机碳和水溶性有机碳则分别较CK稻田降低11.9%和9.9%。施硅处理(Si和NW+Si)根际土的CH_(4)好氧氧化速率显著高于不施硅处理(CK和NW)(P<0.05),其中Si处理的氧化速率最高,为10.9μg/(g·d),较NW处理提高45.3%。施硅处理(Si和NW+Si)非根际土壤中CH_(4)氧化驱动的^(13)C有机碳(^(13)C-SOC)净增量为12.5~13.2μmol/g,固碳效率达61%~66%,均高于不施硅处理(CK和NW)。添加氮条件下4个处理的CH_(4)氧化速率总体上大幅增加,其中以NW+Si处理的非根际土最明显。相反,氮添加对稻田的^(13)C-SOC净增量无明显影响,从而降低了稻田土壤CH_(4)氧化驱动的固碳效率。【结论】施硅可缓解夜间增温对稻田CH_(4)氧化过程的抑制作用,同时也提高其固碳效率。【Objective】To study effects of silicon fertilizer on aerobic CH_(4) oxidation rate in paddy field under warming condition,so as to provide scientific basis for exploring measures of greenhouse gas emission reduction under the background of global warming in the future.【Method】Open field warming system was used to warm the paddy soils at night.Four field treatments were set up:no silicon application at ambient nighttime temperature(CK),no silicon application at nighttime warming(NW),silicon application at ambient nighttime temperature(Si) and silicon application at nighttime warming(NW+Si).The rhizosphere and non-rhizosphere surface soils were collected after four years of abovementioned treatments.Soil under the conditions of no nitrogen and nitrogen addition(NH_(4)^(+),NO_(3)^(-),urea)was used to study the aerobic CH_(4) oxidation rate,and its carbon sequestration characteristics and its response to nitrogen(N)fertilization.【Result】Total organic carbon content and water-soluble organic carbon content in paddy field under Si treatment were 23.2 g/kg and 216.7 mg/kg,which were 10.5% and 26.7% higher than those in CK paddy field,respectively.However,organic carbon and water-soluble organic carbon in paddy field under NW treatment were 11.9% and 9.9% lower than that in CK paddy field.Aerobic CH_(4) oxidation rates in rhizosphere soil under silicon application(Si and NW+Si treatments)were significantly higher than that under no silicon application(CK and NW treatments),and oxidation rate of paddy soils under Si treatment was 10.9 μg/(g·d),which was 45.3% higher than paddy field under NW treatment.Net increment of ^(13)C soil organic carbon(^(13)C-SOC) driven by CH_(4) oxidation in non-rhizosphere soils under silicon treatment(Si and NW+Si)were 12.5-13.2 μmol/g,and carbon sequestration efficiency was 61%-66%,significantly higher than those in paddy field under no-silicon treatment(CK and NW).This indicated that silicon application was in favor of more ^(13)C-CH_(4) carbon sequestration into SOC during a

关 键 词：CH_(4)好氧氧化 夜间增温 施硅 固碳效率 

分 类 号：S154.1[农业科学—土壤学]