增温条件下施硅对稻田CH4厌氧氧化过程的影响  

Effects of silicon application on anaerobic CH4 oxidation in a paddy field under nighttime warming

作　　者：谢晴 薛梦琪 周聪 张耀鸿[1] 娄运生[1] 高霄鹏 贾仲君[2] XIE Qing;XUE Mengqi;ZHOU Cong;ZHANG Yaohong;LOU Yunsheng;GAO Xiaopeng;JIA Zhongjun(Collaborative Innovation Center for Forecast and Evaluation of Meteorological Disasters/Jiangsu Provincial Key Laboratory of Agricultural Meteorology,Nanjing University of Information Science and Technology,Nanjing 210044,China;State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;Department of Soil Science,University of Manitoba,Winnipeg 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,南京210044 [2]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,南京210008 [3]加拿大曼尼托巴大学土壤科学系,加拿大温尼伯R3T2N2

出　　处：《农业环境科学学报》2023年第2期472-480,共9页Journal of Agro-Environment Science

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：硅是水稻生长的有益元素,为研究施硅对稻田CH_(4)厌氧氧化过程的影响以及是否会改变夜间增温对该过程的影响效应,本试验设置夜间常温不施硅(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)4个处理。采集上述田间处理4 a后的耕层土壤,采用13CH_(4)同位素标记法研究稻田土壤CH_(4)厌氧氧化速率和固碳特征及其对氮输入的响应。结果表明:NW处理的CH_(4)厌氧氧化速率为6.23 nmol·g^(-1)·d^(-1)(以^(13)CO_(2)计),显著低于CK处理;与NW处理相比,NW+Si处理的CH_(4)厌氧氧化速率提高了22%。NW处理土壤中CH_(4)氧化驱动的13C有机碳净增量(13C-SOC)为0.31μmol·g^(-1),与NW+Si无明显差异,这表明增温条件下施硅对稻田土壤CH_(4)厌氧氧化的固碳量无明显影响。添加N条件下4个稻田土壤的CH_(4)厌氧氧化速率总体上明显减小,其中以Si处理土壤最为突出,下降29%~50%。相反,N添加提高了CH_(4)厌氧氧化的固碳效率[13C-SOC(/13C-SOC+^(13)CO_(2))]。研究表明,施硅可缓解夜间增温对稻田CH_(4)氧化速率的抑制作用,但对其固碳量无明显影响;外源N可提高增温/施硅稻田土壤CH_(4)厌氧氧化的固碳效率,有利于将较高比例的13C-CH_(4)碳源固定到土壤有机碳中。Si is a beneficial element for rice growth.The effects of Si application on the CH_(4)oxidation process in paddy fields and whether it will change the effect of nighttime warming on this process are still unclear.In this study,the four treatments included no Si application at ambient nighttime temperature(CK)and at nighttime warming(NW),and silicon application at ambient nighttime temperature(Si)and at nighttime warming(NW+Si).The surface soils were collected after four years of the above-mentioned treatments,and the 13CH_(4)isotope labeling method was used to study the anaerobic CH_(4)oxidation rates,its 13C sequestration,and its response to nitrogen(N)fertilization.The results showed that the anaerobic CH_(4)oxidation rate under NW treatment,which was 6.23 nmol·g^(-1)·d^(-1)(in terms of^(13)CO_(2)),was significantly lower than that under CK treatment.The rate of NW treatment significantly increased by 22%under NW+Si treatment.The net increment of 13C soil organic carbon(13C-SOC)driven by 13CH_(4)oxidation under NW treatment,which was 0.31μmol·g^(-1)and significantly lower than that in CK paddy soils,was not significantly different than that in NW+Si paddy field.This indicated that Si application had no significant effect on the carbon sequestration of CH_(4)anaerobic oxidation in the nighttime warming paddy field.The anaerobic CH_(4)oxidation rates of paddy fields substantially decreased 29%-50%under N fertilization,especially in paddy soils under Si treatment.In contrast,N fertilization remarkably increased the carbon sequestration efficiency[13C-SOC(/13C-SOC+^(13)CO_(2))]of CH_(4)anaerobic oxidation.In conclusion,silicon application could alleviate the inhibitory effect of nighttime warming on the CH_(4)oxidation process in paddy fields but had no significant effect on carbon sequestration.N fertilization could improve the carbon sequestration efficiency of CH_(4)anaerobic oxidation in paddy fields,which favored fixing a higher proportion of 13C-CH_(4)into soil organic carbon in the process of CH_(4)oxida

关 键 词：甲烷 厌氧氧化 夜间增温 施硅 固碳效率 稻田 土壤 

分 类 号：X71[环境科学与工程—环境工程] S154.1[农业科学—土壤学]