A MULTI-YEAR STUDY ON BIODIVERSITY AND DOMINANCE OF PLANKTON IN JIAOZHOU BAY

Strong influences of human activities had resulted in great changes of biodiversity andabundance in the Jiaozhou Bay ecosystern in the past decades. This paper reports the long-term changes ofthe biodiversity index and dominance index of phytoplankton and zooplankton in Jiaozhou Bay since 1991,based on the database of JERS, CERN. The biodiversity of phytoplankton showed a slightly increasingtendency and that of zooplankton a declining tendency since the 1990s. The dominancy index of phyto-

Strong influences of human activities had resulted in great changes of biodiversity and abundance in the Jiaozhou Bay ecosystem in the past decades. This paper reports the long-term changes of the biodiversity index and dominance index of phytoplankton and zooplankton in Jiaozhou Bay since 1991 , based on the database of JERS, GERM. The biodiversity of phytoplankton showed a slightly increasing tendency and that of zooplankton a declining tendency since the 1990s. The dominancy index of phytoplankton showed a little decreasing trend and that of zooplankton a somewhat increasing trend during the same period. The total species of both phytoplankton and zooplankton indicated a slightly increasing trend. We suppose that the changes of biodiversity, abundance and total species were due to the heavy negative influence of human activities in the past decades and to the positive contribution of environmental protection measures in recent years.