A two-dimensional flow model coupled with a nutrient, phytoplankton, zooplankton, and detritus (NPZD) ecosystem model was applied to simulate the thermal discharge of two nuclear power plants near Daya Bay of South China Sea, and their impact on hydrodynamic conditions and ecosystem. The results show that the thermal discharge influence area of neap tide is much larger than spring tide, and the high and mid temperature rise area in winter is much larger than that in summer. More importantly, the present data further confirmed that the Daya Bay ecosystem has significant responses to the thermal discharge in nutrients, phytoplankton and zooplankton. In winter and early spring, the thermal discharge facilitates the growth of phytoplankton and their abundance often peak in March and April. In summer, the thermal discharge inhibits the growth of phytoplankton and their abundance keep at a low level from June to August. Although the abundance of zooplankton changed with phytoplankton, the characteristic of seasonal variation of zooplankton do not coincide with the phytoplankton, but are lagged in time, by nearly one month. Moreover, the concentration of nutrients and chlorophyll a were compared between thermal discharge and the nearby aquaculture, which has shown that the aquaculture contributed more to the eutrophication.

中文翻译：

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模拟半封闭的大亚湾生态系统对附近两个核电站的热排放的响应。

应用二维流模型，结合营养物，浮游植物，浮游动物和碎屑（NPZD）生态系统模型，模拟了南海大亚湾附近两座核电站的热排放及其对水动力条件和生态系统的影响。结果表明，潮汐的热影响面积比潮汐的要大得多，冬季的高中温升区要比夏季大。更重要的是，目前的数据进一步证实，大亚湾生态系统对养分，浮游植物和浮游动物的热量排放具有显着响应。在冬季和早春，热量的释放促进了浮游植物的生长，其丰度通常在三月和四月达到峰值。在夏天，热量释放抑制了浮游植物的生长，其丰度在6月至8月保持在较低水平。尽管浮游动物的数量随着浮游植物的变化而变化，但是浮游动物的季节性变化特征与浮游植物并不吻合，而是在时间上滞后了近一个月。此外，比较了热排放和附近水产养殖中养分和叶绿素a的浓度，这表明水产养殖对富营养化的贡献更大。