Due to the further intense human urbanization and industrialization,the environmental problems and climate changes became global issues that we have to face today.Like increasing environmental pollutants,ocean eutroph...Due to the further intense human urbanization and industrialization,the environmental problems and climate changes became global issues that we have to face today.Like increasing environmental pollutants,ocean eutrophication,red-tide and acidification are causing irrevocably damages to the marine ecological environment.As an important part of marine ecosystem,macrobenthos plays an essential role in energy flow and substance circulation in the marine ecosystem.Therefore,the study of macrobenthic community structures and diversities were necessary,meanwhile the protection of macrobenthic diversity was also a tough problem.In recent years,many researches were mainly focus on Jiaozhou Bay of the Yellow Sea,the Yangtze Estuary,the coastal of Zhejiang and Fujian Provinces,while seldom on benthic organisms in the Bohai Sea.In this paper,the community structures and diversities of the common macrobenthos in the Bohai Sea were introduced and the macrobenthic response to environmental changes and environmental pollution caused by the construction of the Bohai Sea were also mentioned.The results showed that the large benthic fauna in th Bohai Sea was relatively simple compared to other China seas.There were about 400 species of large benthic organisms.The dominant species were low temperature and wide salt warm water.In the last five years,the annual average biomass was 23.82 g/m^2 and the annual average density was 1498 ind/m^2.The seasonal variation of average habitat density was usually summer autumn spring winter,and the average biomass was usually autumn spring summer winter.Original communities were destroyed and the dominant species appeared to be miniaturized caused by abuse of marine resources.Since the 21st century,the number of crustacean arthropods,bivalve molluscs,and echinoderms have decreased rapidly,but the number of polychaetes and small molluscs increased gradually.With the development of the comprehensive ecological management of the Bohai Sea,the ecological environment and habitat status in the studied area were remedied and improved.Afterwards,the trend of miniaturization was also suppressed.The results of this study presented some existed problems about marine ecological survey and provided some reasonable suggestions for the rational utilization and protection of marine resources.展开更多
Seasonal cycle is the most significant signals of topography and circulation in the Bohai Sea (BS)and Yellow Sea (YS) forced by prevailing monsoon and is still poorly understood due to lack of data in their interiors....Seasonal cycle is the most significant signals of topography and circulation in the Bohai Sea (BS)and Yellow Sea (YS) forced by prevailing monsoon and is still poorly understood due to lack of data in their interiors. In the present study, seasonal cycles of topography in the BS and YS and its relationship with atmospheric forcing and oceanic adjustment were examined and discussed using TOPEX/Poseidon and ERS-1/2 Sea Level Anomalies (SLA) data. Analyses revealed complicated seasonal cycles of topography composed mainly of2 REOF modes, the winter-summer mode (WIM) and spring-autumn mode (SAM). The WIM with action center in the BS displayed peak and southward pressure gradient in July, and valley and northward pressure gradient in January, which is obviously the direct response to monsoon with about 1-month response time. The SAM with action center in the western south YS displayed peak and northward pressure gradient in October and valley and southward pressure gradient in April. After the mature period of monsoon, the action center in the BS became weakened while that in the western south YS became strengthened because of regional convergence or divergence induced by seasonal variations of the Taiwan Warm Current and Yellow Sea Coastal Current. The direct response of topography to monsoon resulted in the WIM, while oceanic adjustment of topography played an important role in the forming of the SAM.展开更多
文摘Due to the further intense human urbanization and industrialization,the environmental problems and climate changes became global issues that we have to face today.Like increasing environmental pollutants,ocean eutrophication,red-tide and acidification are causing irrevocably damages to the marine ecological environment.As an important part of marine ecosystem,macrobenthos plays an essential role in energy flow and substance circulation in the marine ecosystem.Therefore,the study of macrobenthic community structures and diversities were necessary,meanwhile the protection of macrobenthic diversity was also a tough problem.In recent years,many researches were mainly focus on Jiaozhou Bay of the Yellow Sea,the Yangtze Estuary,the coastal of Zhejiang and Fujian Provinces,while seldom on benthic organisms in the Bohai Sea.In this paper,the community structures and diversities of the common macrobenthos in the Bohai Sea were introduced and the macrobenthic response to environmental changes and environmental pollution caused by the construction of the Bohai Sea were also mentioned.The results showed that the large benthic fauna in th Bohai Sea was relatively simple compared to other China seas.There were about 400 species of large benthic organisms.The dominant species were low temperature and wide salt warm water.In the last five years,the annual average biomass was 23.82 g/m^2 and the annual average density was 1498 ind/m^2.The seasonal variation of average habitat density was usually summer autumn spring winter,and the average biomass was usually autumn spring summer winter.Original communities were destroyed and the dominant species appeared to be miniaturized caused by abuse of marine resources.Since the 21st century,the number of crustacean arthropods,bivalve molluscs,and echinoderms have decreased rapidly,but the number of polychaetes and small molluscs increased gradually.With the development of the comprehensive ecological management of the Bohai Sea,the ecological environment and habitat status in the studied area were remedied and improved.Afterwards,the trend of miniaturization was also suppressed.The results of this study presented some existed problems about marine ecological survey and provided some reasonable suggestions for the rational utilization and protection of marine resources.
文摘Seasonal cycle is the most significant signals of topography and circulation in the Bohai Sea (BS)and Yellow Sea (YS) forced by prevailing monsoon and is still poorly understood due to lack of data in their interiors. In the present study, seasonal cycles of topography in the BS and YS and its relationship with atmospheric forcing and oceanic adjustment were examined and discussed using TOPEX/Poseidon and ERS-1/2 Sea Level Anomalies (SLA) data. Analyses revealed complicated seasonal cycles of topography composed mainly of2 REOF modes, the winter-summer mode (WIM) and spring-autumn mode (SAM). The WIM with action center in the BS displayed peak and southward pressure gradient in July, and valley and northward pressure gradient in January, which is obviously the direct response to monsoon with about 1-month response time. The SAM with action center in the western south YS displayed peak and northward pressure gradient in October and valley and southward pressure gradient in April. After the mature period of monsoon, the action center in the BS became weakened while that in the western south YS became strengthened because of regional convergence or divergence induced by seasonal variations of the Taiwan Warm Current and Yellow Sea Coastal Current. The direct response of topography to monsoon resulted in the WIM, while oceanic adjustment of topography played an important role in the forming of the SAM.