乌江流域颗粒态有机碳的时空分布特征  

Spatial and seasonal variability of particulate organic carbon in the Wujiang River

作　　者：张金华 黄佳琦 林昕 汪福顺[1] 马静[1] ZHANG Jinhua;HUANG Jiaqi;LIN Xin;WANG Fushun;MA Jing(School of Environmental and Chemical Engineering,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海大学环境与化学工程学院,上海200444

出　　处：《上海大学学报（自然科学版）》2021年第2期250-259,共10页Journal of Shanghai University:Natural Science Edition

基　　金：国家重点研发计划资助项目(2016YFA0601003)。

摘　　要：以乌江为研究对象,采集了乌江干流7座大型水库及猫跳河支流红枫水库的表层水体悬浮颗粒物(total suspended matter,TSM)样品,测定了其表层颗粒态有机碳(particulate organic carbon,POC)和稳定碳同位素(δ13C),并以木质素作为陆源有机质的生物标志物,分析了乌江流域水库有机碳的空间和季节分布特征.结果表明:表层水体TSM质量浓度受季节影响显著,呈现出春夏季高于秋冬季的趋势;POC和木质素含量(∑8和Λ8)差异受季节影响较大,其中秋冬季上游POC含量显著高于下游,体现出梯级筑坝拦截效应;∑8与Λ8呈显著线性相关,都表现出明显的秋冬季高丁春夏季的趋势.表层水体TSM的δ13C值明显偏负,可能是由于陆源植物碎屑和淡水浮游生物更容易存在于表层水体.木质素参数信息反映出流域内的优势植被种群为被了植物,TSM样品的陆源有机质是由多种类型植物共同混合、降解、运输至河流的.TSM样品的降解水平不高,7月、10月个别采样点出现了较高的降解水平.Surface water samples were collected from seven cascade reservoirs across the mainstream Wujiang River and Hongfeng Reservoir on the tributary of Maotiao River,to measure the concentration of total suspended matter(TSM).Samples were analysed for elemental and stable carbon isotopic(δ13C) composition and lignin phenols to investigate the variability in the spatial and seasonal distribution of particulate organic carbon(POC).The TSM in surface water varied greatly across the seasons.It was higher in the spring and summer than in autumn and winter.POC and lignin content(E8 and A8,respectively)in surface water showed high variability that were greatly influenced by season.POC in upstream waters was higher than in downstream waters in the autumn and winter,reflecting dam interception.E8 and A8 in the TSM samples exhibited a significant linear relationship,stronger in autumn and winter than in spring and summer.The δ13C of TSM was significantly negative.This was potentially due to the more depleted δ13C of terrestrial plant debris and freshwater plankton,that was likely to exist in surface water.Angiosperms were the dominant vegetation species reflected by lignin.There was a high diversity in the plant sources of terrestrial organic matter in surface particulate matter samples.The extent of degradation of TSM samples was relatively low,and aggravated degradation was observed in July and October,likely related to vigorous microbial activity.

关 键 词：乌江流域 颗粒态有机碳 水库 时空分布 木质素 梯级筑坝 

分 类 号：X820[环境科学与工程—环境工程]