辽河口生态修复区CH_(4)排放通量季节变化研究  

Seasonal characteristics of CH_(4) flux in a restored salt marsh wetland at Liao River estuary

作　　者：邢庆会 程浩 刘思琪 徐雪梅[1] 陈虹[1] 韩建波[1] 杜金秋[1] XING Qing-hui;CHENG Hao;LIU Si-qi;XU Xue-mei;CHEN Hong;HAN Jian-bo;DU Jin-qiu(State Environmental Protection Key Laboratory of Marine Ecosystem Restoration,National Marine Environmental Monitoring Center,Dalian 116023,China;College of Marine Ecology and Environment,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]国家海洋环境监测中心,国家环境保护海洋生态环境整治修复重点实验室,辽宁大连116023 [2]上海海洋大学海洋生态与环境学院,上海201306

出　　处：《中国环境科学》2023年第11期6123-6131,共9页China Environmental Science

基　　金：国家重点研发计划项目(2022YFE0209300);国家自然科学基金项目(41876128);山东省海洋生态修复重点实验室开放基金项目(201914)。

摘　　要：为探究盐沼湿地生态修复区生态系统−大气界面CH_(4)排放通量季节变化特征及其主要影响因子,采用涡度相关法,利用2016~2021年辽河口“退塘还湿”修复区的CH_(4)通量观测数据,分析了区域CH_(4)通量四季平均日变化特点及其主要气象影响因子.结果表明,辽河口“退塘还湿”生态修复区域,不同季节CH_(4)通量值的平均日变化波动趋势和范围不同.夏、秋和冬季白天CH_(4)通量值在零左右波动,四季CH_(4)排放平均日变化峰值分别出现在05:30、01:30、02:30和09:00,整体上表现为12:00之前为CH_(4)源,12:00之后为弱CH_(4)汇或CH_(4)源/汇功能不明显.辽河口“退塘还湿”修复区,四季CH_(4)通量平均日变化振幅大小和日平均值均表现为冬季>春季>夏季>秋季.修复区CH_(4)排放的主要影响因素为空气温度(Ta)、光合有效辐射(PAR)和风速(WS).其中,春季Ta与CH_(4)通量显著负相关,WS与CH_(4)通量显著正相关,两变量共解释43.8%的CH_(4)通量变动;夏季PAR与CH_(4)通量显著负相关;冬季,Ta与CH_(4)通量显著负相关,PAR与CH_(4)通量显著正相关.辽河口“退塘还湿”修复区多年不同季节生态系统−大气界面的CH_(4)通量范围为−60.9~155nmol/(m^(2)·s),CH_(4)通量平均值为14.05nmol/(m^(2)·s),多年CH_(4)平均净释放量为5.32gC/(m^(2)·a),即辽河口“退塘还湿”修复区表现为CH_(4)的源,单位面积百年增温潜势为198.46g CO_(2)-eq/m^(2).本研究对充分认识滨海盐沼湿地碳源/汇功能和合理评估湿地修复效果具有重要意义.Using the Eddy Covariance(EC)technique,the seasonal characteristics of CH_(4) flux between a restored salt marsh and atmosphere were analyzed and its main influencing factors during the period between 2016~2021 in the Liao River estuary were determined.The results showed that the average diurnal fluctuation trend and range of CH_(4) flux values were different in four seasons in the restored salt marsh.The CH_(4) flux fluctuates around zero during the daytime in summer,autumn and winter.The peak CH_(4) emission occurred at 05:30,01:30,02:30 and 09:00 respectively in four seasons.On the whole,the salt marsh was usually shown as a CH_(4) source before 12:00 and a weak CH_(4) sink or an insignificant CH_(4) source/sink after 12:00.Both the amplitudes and average values of the diurnal variation of CH_(4) fluxes were winter,spring,summer and autumn in descending order in the restored salt marsh.The main influencing factors of CH_(4) release in the restored area were Ta,PAR and WS.In spring,Ta and CH_(4) flux were negatively correlated,while WS and CH_(4) flux were positively correlated,Ta and WS accounting for 43.8%of the CH_(4) flux variation.In summer,PAR and CH_(4) flux were negatively correlated,while PAR was significantly positively correlated with CH_(4) flux.In the restored salt marsh of the Liao River estuary,during the year of 2016~2021,the CH_(4)flux values ranged from−60.9 to 155nmol/(m^(2)·s)in different seasons,the average CH_(4) flux value was 14.05nmol/(m^(2)·s).In general,the restored salt marsh acted as a CH_(4) source(5.32gC/(m^(2)·a)),with a global warming potential(GWP)of 198.46g CO_(2)-eq/m^(2).

关 键 词：涡度相关 CH_(4)通量 池塘养殖 退塘还湿 滨海蓝碳 

分 类 号：X52[环境科学与工程—环境工程]