中国近海区域浮游植物生态对气候变化的响应

Response of phytoplankton in offshore China seas to climate change

我国近海区域对气候变化高度敏感,浮游植物生态的变化关系到我国近海生态安全.采用重构的遥感数据等资料,分析并综述我国近海区域浮游植物叶绿素a浓度、初级生产力和浮游植物群落结构对气候变化背景下海水升温、风场等环境因子的响应.结果表明,东(南)中国海叶绿素a浓度略有上升(下降)的趋势,但浮游植物群落结构和生物量有明显的变化;其中,微微型浮游植物和甲藻占比增加,小型浮游植物物种成为海区优势种,暖水性种分布区北扩,而这与气候变化背景下海洋热动力环境的长期变化及其对营养盐供给的影响关系密切.分析还指出了气候变化对我国近海区域海洋生态影响研究迫切需要开展的若干工作.

As important marginal seas of western North Pacific Ocean,the East China Seas( ECS,including the Yellow Sea and Bohai Sea,here) and the South China Sea( SCS) has been subject to the impacts of global climate change in terms of primary production and fishery production. Thus,it is important to analyze and review the phytoplankton response to global climate change. This paper uses the reconstructed remote sensing data and references to analyze and review the interannual and interdecadal effects of Sea Surface Temperature( SST) and some other factors such as wind field on chl-a,primary production,abundance and biomass. This paper also analyze phytoplankton community structures in recent decades,and discusses the causes of dominance of nanophytoplankton and picophytoplankton and dinoflagellates,and the appearance of warm water phytoplankton species in offshore China seas and adjacent sea areas. The result shows that phytoplankton community structure and biomass has changed significantly with dominating picophytoplankton and dinoflagellates and northward distribution of warm water species. In addition,the chl-a biomass increase( decrease) slightly in the ECS( the SCS) and it shows much complicated relations with SST warming though there may have shown positive( negative) correlations. We also find that SST warming has less effects on chl-a and primary productivity in the ECS compared with the SCS because of interactions of East Asia monsoon,near shore circulation and the supply of terrigenous nutrients to the sea. Picophytoplankton and dinoflagellates trend to dominate in poor nutrient waters due to SST warming and nutrient structure variation,which becomes complicated due to overlapping effects of environment factors. At last,imperative studies are proposed for the impact of global climate change on the marine ecosystem of the offshore China seas and adjacent sea areas.