不同海拔茶园土壤N_(2)O排放的温度敏感性  

Temperature Sensitivity of Soil Nitrous Oxide Emissions in Tea Plantations at Different Elevations

作　　者：沈梦雪 王金阳[1,2] 李竹焘 林海燕 郭姝敏 邹建文 SHEN Meng-xue;WANG Jin-yang;LI Zhu-tao;LIN Hai-yan;GUO Shu-min;ZOU Jian-wen(Key Laboratory of Green and Low-carbon Agriculture in Southeastern China,Ministry of Agriculture and Rural Affairs,College of Resources and Environmental Sciences Nanjing Agricultural University,Nanjing 20095,China;Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation,College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学资源与环境科学学院,农业农村部东南沿海农业绿色低碳重点实验室,南京210095 [2]南京农业大学资源与环境科学学院,江苏省低碳农业与温室气体减排重点实验室,南京210095

出　　处：《环境科学》2024年第12期7401-7409,共9页Environmental Science

基　　金：国家自然科学基金项目(42177285,42007072)。

摘　　要：针对氧化亚氮(N_(2)O)排放对增温响应在不同生物群落中可能存在差异和茶园土壤高度异质性会加剧其对增温响应的不确定性的问题,以海拔分别为(E1)537、(E2)433、(E3)350、(E4)308和(E5)238 m的茶园土壤为对象,在3个温度(15、25和30℃)下进行了为期35 d的培养实验,探究不同海拔茶园土壤N_(2)O温度敏感性及其驱动因素.结果表明,增温会促进不同海拔茶园土壤N_(2)O排放,但对于不同海拔的影响并不一致.具体而言,增温降低了E1处理的N_(2)O累计排放量,但差异不显著;同时增加了E2~E5处理的N_(2)O累计排放量,其中E3~E5处理的排放量显著增加.不同海拔茶园土壤N_(2)O的Q_(10)值之间存在极显著差异,Q_(10)值的范围为0.90~4.98,其中:E4>E5>E3>E2>E1.多元回归模型分析表明,土壤理化和微生物共同解释了不同海拔茶园土壤N_(2)O温度敏感性变异的97.4%,其中N_(2)O温度敏感性与细菌beta多样性PCo A1显著正相关.研究结果认为,增温可促进不同海拔茶园土壤N_(2)O排放,但海拔与N_(2)O温度敏感性变化之间没有一致的变化规律,而N_(2)O温度敏感性主要受细菌beta多样性的影响.To solve the problems that the response of nitrous oxide(N_(2)O)emissions to warming may be different in different biological communities and the uncertainty of its response to warming may be aggravated by the high heterogeneity of tea plantation soils,an incubation experiment at five elevations of tea plantation soils[537 m(E1),433 m(E2),350 m(E3),308 m(E4),and 238 m(E5)]and three temperatures(15,25,and 30℃)was conducted for 35 days to explore the temperature sensitivity of N_(2)O in different tea plantation soils and the driving factors.The results showed that elevated temperature could promote soil N_(2)O emissions at different elevations,but the effect was inconsistent at different elevations.Specifically,elevated temperature decreased the cumulative N_(2)O emissions in the E1 treatment,but the difference was not significant.At the same time,the cumulative N_(2)O emissions in the E2-E5 treatments were increased,especially in the E3-E5 treatments.The Q_(10) values of N_(2)O in the tea plantation soils at different elevations were significantly different,ranging from 0.90 to 4.98,with E4>E5>E3>E2>E1.The multiple regression model analysis showed that 97.4%of the variation in N_(2)O temperature sensitivity was explained by soil physicochemistry and microorganisms,and N_(2)O temperature sensitivity was significantly positively correlated with bacterial beta diversity PCoA1.In conclusion,increasing temperature can promote the N_(2)O emissions in tea plantation soils at different elevations,but there is no consistent change rule between elevation and N_(2)O temperature sensitivity,and N_(2)O temperature sensitivity is mainly affected by the bacterial beta diversity.

关 键 词：氧化亚氮(N_(2)O) 温度敏感性(Q_(10)) 茶园 海拔 增温 

分 类 号：X16[环境科学与工程—环境科学]