在生态环境调查与分析的基础上,制定了金山城市沙滩人工潟湖水体生态修复方案,评估该生态修复工程的效果。结果表明,通过养殖大型海藻(江蓠)、构建人工湿地和调控水生食物网结构等措施后,人工潟湖水体富营养化得到有效控制,水体中无机氮和无机磷浓度分别下降42%和50%。另外,人工潟湖水生食物网结构得到明显优化与改善,生态修复后浮游动物平均丰度约是生态修复前的3.5倍,大型底栖动物密度和生物量分别是修复前的16倍和36倍。可见,通过生态修复工程的实施提高了浮游动物和底栖动物的丰度,优化了水生生物群落结构,是近岸富营养化水体生态修复的成功案例之一。
The ecological restoration item was programmed in an artificial lagoon located in the Jinshan dis- trict in Shanghai and its effectiveness in controlling the eutrophication of the enclosed lagoon was assessed in the Hangzhou Bay. The main ecological restoration measurements were consisted of seaweed (Gracilar- ia verrucosa) culture, construction of artificial wetland by transplanting native marsh plants (bulrush Scirpus mariqueter), and manipulation of food web structure of aquatic ecosystem through releasing and stock enhancement of hatchery-reared aguatic species. It was found that in the ecological restoration the water quality in the lagoon was significantly improved, including decrease in dissolved inorganic nitrogen (42 ~) and phosphorus (50 ~). Additionally, the ecological restoration measurements extensively amelio- rated the aquatic food web structure in the lagoon through increase in the abundance of zooplankton and macrobenthos. Zooplankton abundance was found to be increased by 2.5 times compared to that before the ecological restoration, and the mean density and biomass of macrobenthos were 16 and 36 times as higher as that before the ecological restoration. Therefore, the ecological restoration led to increase in abundance of prey species (zooplankton and macrobenthos), and to optimization of the aquatic ecosystem structure in the artificial lagoon, a successive case study for controlling the coastal eutrophication.