白洋淀底泥-水界面溶解性碳交换通量及驱动因素研究  

Study on exchange flux of dissolved carbon and it’s driving factors at the sediment-water interface of Baiyangdian Lake

作　　者：侯钰凡 王仕琴[1,3] 古丛珂 唐誉硕 HOU Yufan;WANG Shiqin;GU Congke;TANG Yushuo(Center for Agricultural Resources Research,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Key Laboratory of Agricultural Water Resources,Chinese Academy of Sciences,Hebei Key Laboratory of Water-Saving Agriculture,Shijiazhuang 050022;Sino-Danish College,University of Chinese Academy of Sciences,Beijing 101408;University of Chinese Academy of Sciences,Beijing 100049)

机构地区：[1]中国科学院遗传与发育生物学研究所农业资源研究中心,中国科学院农业水资源重点实验室,河北省节水农业重点实验室,石家庄050022 [2]中国科学院大学中丹学院,北京101408 [3]中国科学院大学,北京100049

出　　处：《环境科学学报》2024年第9期302-310,共9页Acta Scientiae Circumstantiae

基　　金：河北省创新能力提升计划项目(No.225A3902D);国家自然科学基金项目(No.42071053);河北省科技计划项目(No.215A9915D)。

摘　　要：白洋淀是华北平原最大的淡水湖泊型湿地,底泥和水界面碳的交换过程及通量直接影响白洋淀碳“源汇”功能和水质变化.近年来极端强降水频率增加改变了湿地水动力条件,对底泥-水界面碳交换的影响不明.因此,本文选择白洋淀及其主要入淀河流—府河为研究对象,结合原位箱式培养法与柱状芯样模拟法,分别在极端降雨前后设置芦苇区与非芦苇区原位静态培养对照实验,探究降水条件变化对不同生物区上覆水溶解性碳时空变化及碳通量的影响.结果表明,极端降雨前,芦苇区与非芦苇区相比,河道与淀区监测点的溶解性有机碳(DOC)分别增加了25.27%和36.15%,溶解性无机碳(DIC)分别增加了26.10%和32.48%,溶解性碳(DC)分别增加了25.67%和34.44%,且芦苇区底泥-水界面溶解性碳交换通量比非芦苇区均较高,占比均超过85%;入淀口芦苇区与非芦苇区无显著性差异.极端降雨对上覆水溶解性碳浓度产生了稀释作用,芦苇对底泥-水界面溶解性碳迁移交换过程的影响程度被削弱;DIC由极端降雨前底泥向上覆水的释放转变为向底泥沉积,即底泥由“源”转变为“汇”.该研究可为白洋淀湿地生态系统健康发展提供理论支撑.Baiyangdian Lake is the largest freshwater lake wetland in the North China Plain.The carbon exchange process and flux between sediment-water interface directly affect the function of carbon source and sink of the lake,and water quality change in Baiyangdian Lake.In recent years,the increasing frequency of extreme heavy rainfall has changed the hydrodynamic conditions of the lake,and its effect on carbon exchange at the sediment-water interface is unclear.Therefore,in order to explore the influence of precipitation conditions on the temporal and spatial changes of dissolved carbon in the overlying water and carbon flux of different biological regions,Baiyangdian Lake and its main inlet river,Fu River,were selected to study the exchange flux of dissolved carbon and it’s driving factors at the sediment-water interface.Combined with the in-situ chamber incubation method and the core sediment simulation method,the in-situ incubation control experiments were set in reeds area and non-reeds area before and after extreme rainfall,respectively.The results showed that before extreme rainfall,the concentration of DOC,DIC and DC of water at the sites in the reeds area of river channel and lake area increased by 25.27%and 36.15%,26.10%and 32.48%,25.67%and 34.44%,respectively,when compared with non-reeds area.And the dissolved carbon exchange flux at the sediment-water interface in the reeds area was higher than that in the non-reeds area,accounting for more than 85%.There was no significant difference between reeds area and non-reeds area at the sites of the entrance of lake.Extreme rainfall had a dilution effect on the DC concentration of overlying water,weakening the impact of reeds on the process of dissolved carbon migration and exchange at the sediment-water interface.DIC was released from sediment to overlying water(source)before the extreme rainfall while it was changed to sediment deposition(sink)after the extreme rainfall.This study can provide theoretical support for the healthy development of Baiyangdian Lake eco

关 键 词：溶解性碳 底泥-水界面 交换通量 白洋淀 

分 类 号：X171[环境科学与工程—环境科学]