Long-term changes in sedimentary diatom assemblages and their environmental implications in the Changjiang(Yangtze) River estuary, China  

作　　者：程芳晋 俞志明 宋秀贤 

机构地区：[1]Key Laboratory of Marine Ecology and Environmental Sciences,Institute of Oceanology,Chinese Academy of Sciences [2]University of Chinese Academy of Sciences

出　　处：《Chinese Journal of Oceanology and Limnology》2014年第1期155-161,共7页中国海洋湖沼学报（英文版）

基　　金：Supported by the National Basic Research Program of China(973 Program)(No.2010CB428706);the Funds for Creative Research Groups of China(No.41121064)

摘　　要：Long-term data on diatom assemblages in a sediment core （60 cm） obtained from the Changjiang （Yangtze） River estuary were analyzed in order to assess the environmental changes that took place in the approximately 38 years （as determined by 210pb measurements）, i.e., between 1974 and 2012, of sediment accumulation. From the sediment core, 62 diatom taxa and genera were identified. The diatom biomass in the core generally increased beginning in the mid-1990s （core depth： 35 cm）, accompanied by a shift in the dominant species from Podosira stelliger and two species of Cyclotella （C. stylorum and C. striata） to Paralia sulcata, three species of Thalassiosira （ T. eccentria, I＂. oestrupii, and T. excentrica）, Actinoptychus undulates, and Thalassionema nitzschioides. The changes in both species diversity and abundance suggested that since the 1980s the estuary has undergone extensive eutrophication. This conclusion was supported by the increased proportion of planktonic species, another indicator of high nutrients inputs, in the Changjiang River estuary.Long-term data on diatom assemblages in a sediment core(60 cm) obtained from the Changjiang(Yangtze) River estuary were analyzed in order to assess the environmental changes that took place in the approximately 38 years(as determined by 210 Pb measurements), i.e., between 1974 and 2012, of sediment accumulation. From the sediment core, 62 diatom taxa and genera were identifi ed. The diatom biomass in the core generally increased beginning in the mid-1990s(core depth: 35 cm), accompanied by a shift in the dominant species from Podosira stelliger and two species of Cyclotella( C. stylorum and C. striata) to Paralia sulcata, three species of Thalassiosira( T. eccentria, T. oestrupii, and T. excentrica), Actinoptychus undulates, and Thalassionema nitzschioides. The changes in both species diversity and abundance suggested that since the 1980s the estuary has undergone extensive eutrophication. This conclusion was supported by the increased proportion of planktonic species, another indicator of high nutrients inputs, in the Changjiang River estuary.

关 键 词：diatom assemblages Changjiang River estuary East China Sea environmental implications 

分 类 号：X52[环境科学与工程—环境工程]