Ling Zhang1, Lanlan Xiong2, Jinlong Li2, Xiaoping Huang3. 1. CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong laboratory (Guangzhou), Guangzhou 510301, China. 2. CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China. 3. CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong laboratory (Guangzhou), Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: xphuang@scsio.ac.cn.
Abstract
Long-term changes of nutrients, plankton and macrobenthos were studied to research the transformation of ecosystem in Jiaozhou Bay and Daya Bay in the past 30 years. Concentrations of dissolved inorganic nitrogen and phosphate increased with significant changes in nutrient compositions and ratios. Concentrations of Chl a slightly decreased in Jiaozhou Bay but increased in Daya Bay. Phytoplankton abundances increased and diatoms were dominant, however, dinoflagellate gradually had the competitive advantage under high N/P and N/Si in the two bays. Zooplankton biomass significantly increased in Jiaozhou Bay, but only increased slightly in Daya Bay over the past years. Polychaetes were dominant in macrobenthos in the bays, indicating their adaptation to the changing benthic environments. The long-time variations of biocenoses and nutrients reflected that the ecological environments have changed under the influence of anthropogenic activities in the two bays.
Long-term changes of nutrients, plankton and macrobenthos were studied to research the transformation of ecosystem in Jiaozhou Bay and Daya Bay in the past 30 years. Concentrations of dissolved inorganic pan class="Chemical">nitrogen and n>an class="Chemical">phosphate increased with significant changes in nutrient compositions and ratios. Concentrations of Chl a slightly decreased in Jiaozhou Bay but increased in Daya Bay. Phytoplankton abundances increased and diatoms were dominant, however, dinoflagellate gradually had the competitive advantage under high N/P and N/Si in the two bays. Zooplankton biomass significantly increased in Jiaozhou Bay, but only increased slightly in Daya Bay over the past years. Polychaetes were dominant in macrobenthos in the bays, indicating their adaptation to the changing benthic environments. The long-time variations of biocenoses and nutrients reflected that the ecological environments have changed under the influence of anthropogenic activities in the two bays.