水温与营养值对水库藻华态势的影响

Influence of water temperature and trophic value on algae blooming in reservoirs

主要研究了水温和营养值在大沙河水库绿藻、硅藻藻华生物量的影响;提出了用营养值来定量描述水体的富营养状态;通过构筑一定形式的辅助变量,分别提出了在水温 20 ℃和 30 ℃条件下藻华生物量的预测模型;进一步阐述了水温对藻生长态势的影响原理。研究表明水温一方面影响藻生命活动的活性、速率,另一方面影响藻对水中营养物的利用率和自身代谢率。在水温 20 ℃和 30 ℃时,两方面的总体作用结果有所不同。对营养物的利用率和自身代谢率方面更大程度上影响藻华生物量的多少。

This paper reports the influence of water temperature and trophic value on algae biomass of green algae and diatom blooming in Dashahe Reservoir. It proposes trophic value as a quantitative index of eutrophic state of water body. Through establish- ing some auxiliary parameters, models are also proposed to predicate algae biomass at water temperature 20 ℃ and 30 ℃ accord- ingly. It is observed that algae growth period is longer at water temperature 30 ℃ than it is at 20 ℃. Concretely, lag phase is shorter, log phase and stationary phase both stretch longer. Furthermore influencing theory is proved to divide into two ways. One way is to influence the intensity and velocity of algae growing activities. And the other way is to influence algae utilizing efficiency of nutri- ents in water body outside and metabolizing efficiency itself. There are cooperation and competition between these two ways. It pro- pones utilizing and metabolizing efficiency dominate algae biomass more greatly.