辽河口芦苇盐沼湿地生长季CO_(2)交换及其影响机制  

CO_(2)exchange and its influencing mechanisms in a reed salt marsh in the Liaohe River estuary during the growing season

作　　者：程浩 邢庆会 刘思琪 韩建波[1] 陈虹[1] 张传奇 CHENG Hao;XING Qinghui;LIU Siqi;HAN Jianbo;CHEN Hong;ZHANG Chuanqi(State Environmental Protection Key Laboratory of Marine Ecosystem Restoration,National Marine Environmental Monitoring Center,Dalian 116023,Liaoning,China;College of Marine Ecology and Environment,Shanghai Ocean University,Shanghai 201306,China;Liaoning Green Butler Environmental Technology Co.,Ltd.,Shenyang 110179,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 [3]辽宁绿管家环保科技有限公司,沈阳110179

出　　处：《生态学杂志》2024年第12期3763-3773,共11页Chinese Journal of Ecology

基　　金：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)资助。

摘　　要：为探究滨海盐沼湿地植被生长季生态系统CO_(2)交换特征和影响机制,以辽河口芦苇盐沼湿地为研究对象,采用涡度协方差技术观测净生态系统CO_(2)交换(NEE)特征,并分析了光合有效辐射(PAR)、气温(T_(a))等环境因子和生物量对CO_(2)交换的影响。结果表明:生长季内植被总初级生产力(GPP)、生态系统呼吸(R_(eco))和NEE各月日平均变化曲线分别呈倒“U”型、横向“S”型和“U”型。CO_(2)交换也表现出明显的季节变化规律,GPP和|NEE|在6月累计值最大(分别为273.5、210.5 g C·m^(-2)),R_(eco)在7月累计值最大(76.7 g C·m^(-2))。白天PAR是NEE的主控因子,NEE与PAR符合直角双曲线关系,PAR可解释NEE变异的37.7%~51.6%,且光曲线拟合参数在6月达到最大值。夜晚呼吸(R_(eco),night)受T_(a)、10 cm深土壤含水量(SWC_(10))的协同影响。在不同SWC_(10)范围下,R_(eco),night与T_(a)均呈指数相关关系。当SWC_(10)≤35%时,R_(eco),night值集中于生长季初期和末期,温度敏感性(Q_(10))为1.44;当SWC_(10)>35%时,R_(eco),night值集中于生长季中期(Q_(10)为1.97)和旺盛期(Q_(10)为2.03)。2020年生长季,辽河口芦苇盐沼湿地表现为CO_(2)汇,NEE为-693 g C·m^(-2),GPP为1043 g C·m^(-2),R_(eco)为350 g C·m^(-2)。To investigate the characteristics and influencing mechanisms of ecosystem CO_(2)exchange in salt marsh,we monitored net ecosystem CO_(2)exchange(NEE)using the eddy covariance technique,and analyzed the effects of photosynthetically active radiation(PAR),temperature(T_(a))and biomass on CO_(2)exchange in Liaohe River estuary during the growing season.The results showed that the daily average curves of gross primary productivity(GPP),ecosystem respiration(R_(eco))and NEE of each month showed inverted‘U’,horizontal‘S’and‘U’shape,re⁃spectively.There was seasonal variation for CO_(2)exchange.GPP and|NEE|reached the maximum cumulative values in June(273.5 and 210.5 g C·m^(-2),respectively)and R_(eco) reached the maximum cumulative value in July(76.7 g C·m^(-2)).PAR was the dominant factor of NEE in daytime,with a rectangular hyperbola relationship.PAR explained 37.7%to 51.6%variation of NEE.The parameter of light fitting curve reached a maximum in June.T_(a) and soil water content at 10 cm depth(SWC_(10))synergistically influenced nighttime respiration(R_(eco),night).R_(eco),night and T_(a) showed exponential correlations at different SWC_(10) levels.When SWC_(10)≤35%,R_(eco),night values were derived from early and late growing season,and the temperature sensitivity(Q_(10))was 1.44.When SWC_(10)>35%,R_(eco),night values were derived from middle(Q_(10)=1.97)and vigorous period(Q_(10)=2.03)of the growing season.In the grow⁃ing season of 2020,the reed salt marsh at the Liaohe River estuary acted as a CO_(2)sink,with the NEE,GPP,and R_(eco) being-693,1043,and 350 g C·m^(-2),respectively.

关 键 词：滨海湿地 碳汇 CO_(2)通量 涡度协方差 

分 类 号：X171.1[环境科学与工程—环境科学]