鄱阳湖非淹水期薹草洲滩生态系统呼吸变化及不同观测方法比较  

Variations of ecosystem respiration in Carex meadow of Poyang Lake and comparison between different observation methods during non-flooded periods

作　　者：简正军 吴燕平[1] 方朝阳[1] 叶家飞 尧波[1] 黄琪[1] 胡启武[1] JIAN Zhengjun;WU Yanping;FANG Chaoyang;YE Jiafei;YAO Bo;HUANG Qi;HU Qiwu(School of Geography and Environment&Ministry of Education’s Key Laboratory of Poyang Lake Wetland and Watershed Research,Jiangxi Normal University,Nanchang 330022)

机构地区：[1]江西师范大学地理与环境学院,鄱阳湖湿地与流域研究教育部重点实验室,南昌330022

出　　处：《环境科学学报》2025年第3期441-450,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.32060275);江西省自然科学基金重点项目(No.20212ACB203006);江西师范大学研究生创新基金项目(No.YJS2023009)。

摘　　要：研究湿地生态系统呼吸(Reco,ecosystem respiration)变化特征对评价湿地生态系统碳汇功能具有重要意义.采用不同方法观测Reco,不仅有助于降低Reco评估的不确定性,也有助于观测方法之间的相互验证.本研究于2023年9月—2024年3月在鄱阳湖南矶湿地国家级自然保护区,采用箱式法和涡度相关法对比分析了东湖薹草洲滩Reco变化规律及影响因素.结果表明:①两种方法测定的Reco季节变化趋势一致,均表现为春秋季节高于冬季;箱式法与涡度相关法测定的Reco范围分别为84.94~718.05 mg·m^(-2)·h^(-1)和63.23~567.55 mg·m^(-2)·h^(-1).②箱式法观测的Reco平均值(309.07 mg·m^(-2)·h^(-1))显著高于涡度相关法观测的平均值(184.09 mg·m^(-2)·h^(-1)),产生这种差异的原因可能是静态箱盖入后,升高了箱内温度,从而高估了生态系统的释放量.③气温、地表温度、土壤5 cm温度和土壤含水量与两种方法观测的Reco均存在显著相关关系(p<0.01),其中气温与箱式法测定的Reco之间相关性最为显著(r=0.87),而地表温度与涡度相关法测定的Reco之间相关性最强(r=0.82).④箱式法与涡度相关法观测的Reco之间存在显著正相关关系(p<0.01),两种方法可以很好地相互验证,二者结合可以有效降低湿地碳通量评估的不确定性.Understanding the variation patterns of ecosystem respiration(R eco)is crucial for evaluating the carbon sequestration capacity of wetland ecosystems.Employing diverse methods to observe R eco not only mitigates uncertainties in its assessment,but also facilitates cross-validation among these observation techniques.This study,conducted in the Poyang Lake Nanji Wetland National Nature Reserve from September 2023 to March 2024,analyzed R eco variations and their influencing factors in a Carex meadow of Dong Lake using static chamber and eddy covariance methods.The results indicated that①both methods showed consistent seasonal trends in R eco,with higher rates in spring and autumn than in winter.R eco values ranged from 84.94 to 718.05 mg·m^(-2)·h^(-1)for the static chamber method,and from 63.23 to 567.55 mg·m^(-2)·h^(-1)for the eddy covariance method,respectively.②The mean value of R eco observed by the chamber method(309.07 mg·m^(-2)·h^(-1))was significantly higher than that by the eddy covariance method(184.09 mg·m^(-2)·h^(-1)).This discrepancy might be attributed to the elevated temperature within the chamber during measurements,potentially leading to overestimation of ecosystem CO_(2)efflux.③Air temperature,surface temperature,soil temperature at 5 cm depth,and soil water content were all significantly correlated with the R eco observed by both methods(p<0.01).The strongest correlation was observed between air temperature and R eco measured by the static chamber method(r=0.87).In contrast,surface temperature showed the strongest correlation with R eco measured by the eddy covariance method(r=0.82).④A highly significant positive correlation(p<0.01)exists between R eco observations by the chamber method and eddy covariance technique,indicating that these two methods can effectively validate each other.the combination of both methods can significantly reduce uncertainties in assessing wetland carbon fluxes.

关 键 词：鄱阳湖湿地 生态系统呼吸 涡度相关 箱式法 

分 类 号：X835[环境科学与工程—环境工程]