关键词: 长江口, 浮游动物, 生物量, 年间变化

Abstract: Based on the data of eight voyage′s cruise investigations in May and August from 2000 to 2003 in the water near the Changjiang estuary, this paper dealt with the approach for the zooplankton biomass and its variation in the area. Results showed that the higher biomass was distribution at the warm current side of the mixed formed by the warm current and the Changjiang freshwaters, while the lower biomass was located at the side of freshwaters in May. In August the higher biomass was distributed at both sides of freshwater and marine waters with the lower biomass in the mixed waters.The annual difference of biomass was related with the force of warm current near the Changjiang estuary in which the higher biomass was in the east. The high biomass area spreads towards the Changjiang estuary to make biomass expanding in waters when the force of warm current became stronger. On contrary, the high biomass area beflated because the force of warm current became weaker. This is why the biomass in the area reduced gradually from 2001 to 2003.The change in the dominant specids of zooplankton was the important reason influencing the diet biomass of Changjiang estuary.

Key words: Changjiang Estuary, zooplankton, biomass, variation