Spatial contrast in phytoplankton, bacteria and microzooplankton grazing between the eutrophic Yellow Sea and the oligotrophic South China Sea  

作　　者：张亚锋 王旭涛 殷克东 

机构地区：[1]School of Marine Sciences, Sun Yat-Sen University, Guangzhou 510006, China [2]Key Laboratory of Marine Resources and Coastal Engineering in Guangdong Province, Guangzhou 510006, China [3]Scientific Institute of Pearl River Water Resources Protection, Guangzhou 510000, China

出　　处：《Journal of Oceanology and Limnology》2018年第1期92-104,共13页海洋湖沼学报（英文）

基　　金：Supported by the Major State Basic Research Development Program of China(No.2012CB956004);the National Natural Science Foundation of China(No.91328203);the Guangdong Department of Science and Technology(No.2013B051000042);the Fundamental Research Funds for Sun Yat-Sen University(Nos.2013420003165005,20144200031680001);the Guangdong Bureau of Oceans and Fisheries(No.20134200042090011)

摘　　要：Three cruises were conducted to investigate the distributions of nutrients,chlorophyll a(Chla),new and regenerated primary production,bacterial abundance and production,and microzooplankton grazing rates in the Yellow Sea(YS)and the South China Sea(SCS)during March and May.As the water column moved from low to high temperature,weak to strong stratification and high to low nutrients from the YS to the SCS,Chl-a,primary production and bacterial biomass decreased.In contrast,bacterial production,microzooplankton grazing and size preference increased from the YS to the SCS.The increasing grazing activity and decreasing f-ratio from the YS to the SCS suggest roles of regenerated nutrients in the supporting the community increased and more bacteria played important roles in the carbon flow in the oligotrophic SCS than in the eutrophic YS.These variabilities force the classical food chain dominated community in the eutrophic waters into the microbial loop,which is dominant in oligotrophic waters.As nutrients decrease,temperature and grazing activity increase from the YS to the SCS.The increasing ratio of integrated bacterial production to integrated primary production indicates that communities change from autotrophy to heterotrophy and waters change from a carbon sink to a carbon source.Three cruises were conducted to investigate the distributions of nutrients, chlorophyll a （Chl- a）, new and regenerated primary production, bacterial abundance and production, and microzooplankton grazing rates in the Yellow Sea （YS） and the South China Sea （SCS） during March and May. As the water column moved from low to high temperature, weak to strong stratification and high to low nutrients from the YS to the SCS, Chl-a, primary production and bacterial biomass decreased. In contrast, bacterial production, microzooplankton grazing and size preference increased from the YS to the SCS. The increasing grazing activity and decreasingyZratio from the YS to the SCS suggest roles of regenerated nutrients in the supporting the community increased and more bacteria played important roles in the carbon flow in the oligotrophic SCS than in the eutrophic YS. These variabilities force the classical food chain dominated community in the eutrophic waters into the microbial loop, which is dominant in oligotrophic waters. As nutrients decrease, temperature and grazing activity increase from the YS to the SCS. The increasing ratio of integrated bacterial production to integrated primary production indicates that communities change from autotrophy to heterotrophy and waters change from a carbon sink to a carbon source.

关 键 词：bacterial production primary production nutrient supply grazing activity Yellow Sea South China Sea 

分 类 号：P[天文地球]