根据现场调查和室内试验工作, 计算珠江口水域浮游植物有效光合作用水体体积, 同时研究浮游动物摄食行为对磷再生的补偿作用, 进而对该水域磷的生物利用状况进行初步评估。分析珠江口2002—2003年的数据发现, 珠江口水域浮游植物有效进行光合作用水体的体积存在季节性变化, 枯水期约为9.7×104m3, 而丰水期约为6.6×104m3。该水域总初级生产量在枯水期约为36kg.d-1, 在丰水期约为31kg.d-1, 呈现枯水期大于丰水期的特点。浮游动物的摄食作用可促进水体中磷的再生, 这部分磷可满足浮游植物生长对磷需求的1.5%—15.6%, 并呈现丰水期大于枯水期的特点。浮游动物摄食作用直接释放的量远大于其自身生理周转释放的量。

Available water volume for phytoplankton photosynthesis, effect of zooplankton grazing on the regeneration of phosphorus and bio-utilization of phosphorus in the waters of the Pearl River Estuary were studied by both field and laboratory experiments. Analysis of the data between 2002 and 2003 indicated that the available water volume for phytoplankton photo-synthesis changed seasonally, with about 9.7×104m3 in dry season and 6.6×104m3 in wet season. The same trend was also found in primary productivity, with approximate 36kg.d-1 in dry season and 31kg.d-1 in wet season, respectively. Phosphorus regen-eration could be accelerated by zooplankton grazing and could meet 1.5%-15.6% of phosphorus required by phytoplankton growth seasonally. Amount of phosphorus that directly released from zooplankton grazing was much higher than that from zooplankton biological turnover.

中科院创新项目(KZCX2-YW-JS206, KZCX2-YW-215); 中科院–国家外专局创新团队国际合作伙伴计划项目(KZCX2-YW- T001); 国家自然科学基金(40206016, U0633007); 中国科学院野外台站基金。

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