辽河口“退塘还湿”修复区生态系统CO_(2)交换及其环境调控  

Ecosystem CO_(2) Exchange and Its Environmental Regulation of a Restored Wetland in the Liaohe River Estuary

作　　者：刘思琪 陈虹[2] 邢庆会 程浩 韩建波[2] 徐雪梅[2] LIU Si-qi;CHEN Hong;XING Qing-hui;CHENG Hao;HAN Jian-bo;XU Xue-mei(College of Marine Ecology and Environment,Shanghai Ocean University,Shanghai 201306,China;State Environmental Protection Key Laboratory of Marine Ecosystem Restoration,National Marine Environmental Monitoring Center,Dalian 116023,China)

机构地区：[1]上海海洋大学海洋生态与环境学院,上海201306 [2]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,大连116023

出　　处：《环境科学》2024年第2期920-928,共9页Environmental Science

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);国家重点研发计划项目(2022YFE0209300)。

摘　　要：滨海湿地因其碳汇功能强大,在减缓全球气候变化中发挥着重要作用,“退塘还湿”作为近几年我国滨海湿地生态修复开展的主要形式之一,对其碳源/汇功能的研究较为匮乏.基于涡度相关技术,观测了2021年辽河口“退塘还湿”修复区CO_(2)通量,研究了修复区内盐沼湿地生态系统CO_(2)交换特征及其环境调控.结果表明,修复区净生态系统CO_(2)交换(NEE)平均日变化曲线在春季和秋季呈“U”型,在夏季呈“V”型,在冬季呈“一”型,其春、夏、秋和冬季的效率(以C计)分别为-40.06、-63.62、2.33和34.43 g·m^(-2).修复区NEE日累积年内变化整体呈“V”型,NEE、生态系统呼吸(Reco)和总的初级生产力(GPP)月累积差异明显.2021年修复区内光合有效辐射(PAR)是白天NEE的重要调控因子,二者呈直角双曲线关系,PAR可以解释白天NEE变化的53%;空气温度(T_(a))是夜晚生态系统呼吸(R_(eco,night))的主控因子,二者呈指数关系,T_(a)<5.5℃时生态系统呼吸的温度敏感性(Q_(10))为2.19,T_(a)可以解释R_(eco,night)变化的42%,T_(a)≥5.5℃时Q_(10)为1.81,T_(a)可以解释R_(eco,night)变化的51%.另外,2021年生长季辽河口湿地修复区NEE与土壤含水量(SWC)和饱和水汽压差(VPD)均呈显著的线性负相关,而NEE与土壤温度(Ts)和相对湿度(RH)无显著相关.2021年辽河口“退塘还湿”修复区盐沼湿地表现为碳汇,总净固碳量(以C计)为-66.89 g·m^(-2),其具有长期的碳增汇潜力.Coastal wetlands are important carbon sinks,and they contribute to reducing the effects of global warming.This study used the eddy covariance method to detect the CO_(2) flux in the restoration wetland of the Liaohe River estuary in 2021 and investigate the characteristics of ecosystem CO_(2) exchange and its environmental control factors.The aim was to assess the carbon source/sink capacity of salt marshes in the restored area and to provide data support and theoretical basis for evaluating the effectiveness of ecological restoration projects.The study revealed"U"curves in spring and autumn,"V"curves in summer,and horizontal lines in winter for the average daily variation curve of net ecosystem CO_(2) exchange(NEE)in the restored area.Its carbon sink efficiencies were -40.06,-63.62,2.33,and 34.43 g·m^(-2) in the spring,summer,autumn,and winter,respectively.In the restored area,the daily cumulative variation in NEE was"V"shaped,and the monthly cumulative changes in NEE,ecosystem respiration(R_(eco)),and gross primary productivity(GPP)were obviously different.Photosynthetically active radiation(PAR)was an important regulation factor of daytime NEE in the restored area in 2021,and they displayed a rectangular hyperbolic relationship.PAR could explain 53% of the variation in the daytime NEE.Air temperature(T_(a))was the main control factor of Reco,night,and there was an exponential relationship between them.When T_(a)<5.5℃,the temperature sensitivity of ecosystem respiration(Q_(10))was 2.19,and T_(a) could explain 42% of the variation in the R_(eco,night);when T_(a)≥5.5℃,the Q10 was 1.81,and T_(a) could explain 51% of the variation in the R_(eco,night).Additionally,there were significant linear negative correlations between NEE and both soil water content(SWC)and vapor pressure deficit(VPD),whereas NEE was not significantly correlated with soil temperature(Ts)or relative humidity(RH).In 2021,the restored wetland in the Liaohe River estuary acted as a CO_(2) sink,and the total net carbon sequestration was -66.

关 键 词：盐沼湿地 滨海蓝碳 湿地修复 涡度相关(EC) CO_(2)通量 净生态系统CO_(2)交换 

分 类 号：X16[环境科学与工程—环境科学]