沉水植物和浮游动植物在低光和富营养胁迫环境下的研究

Studies on Submerged Macrophytes and Plankton under Low Light and Eutrophic Stress

摘要: 富营养化环境中多种因子会对沉水植物和浮游动植物产生影响，如低光照，高氨氮等，研究其胁迫作用下生物的变化情况对沉水植物、浮游植物和浮游动物的逆境响应机理有重要的意义。本研究探讨弱光环境下，在富营养和超富营养两种营养水平的水泥围隔中，苦草、黄丝草、浮游植物和浮游动物的变化情况。结果表明：1) 低光照环境下沉水植物的生物量不高，并且统计显示在超富营养水平和富营养水平下生长情况差异不显著；2) 虽然超富营养组中混合营养型的裸藻属有一定优势但是浮游植物生物量总体并不高，富营养组中浮游植物受浮游动物胁迫作用更加明显；3) 浮游动物生物量远高于浮游植物生物量，在浮游植物作为食物来源不足时可能主要以细菌类的微生物为食；4) 研究过程未发现轮虫可能与浮游植物生物量较低有关；滤食性较强的枝角类在超富营养池中占优势而主动摄食能力较强的桡足类在富营养池中有一定优势。5) 在环境胁迫条件下，沉水植物、浮游植物和浮游动物都显得很脆弱，种群结构容易变化和更替。

Abstract: Many factors can affect submerged plants and zooplankton in the eutrophic environment, such as low light, high ammonia nitrogen, etc., it is important to study the changes of submerged macrophytes, phytoplankton and zooplankton under environmental stress for their stress response mechanism. This study was conducted to study the changes of Vallisneria natans, Potamogeton maackianus, phytoplankton and zooplankton under low light conditions and eutrophica, hypereutrophic nutrient levels in cement enclosures. The results showed that: 1) the biomass of submerged macrophytes was not high in low light, and there was no significant difference between hyper- eutrophic level and eutrophic level; 2) although Euglena had some advantages, the total biomass of phytoplankton was low, and the stress of phytoplankton by zooplankton was more obvious in the eutrophic group; 3) the biomass of zooplankton is high, which may because feed mainly on bacteria when the phytoplankton is not enough as food source; 4) no rotifer was found in the study, which may be related to the low biomass of phytoplankton. The filter-feeding cladocera was dominant in hyper-eutrophic ponds, while the active feeding copepods were dominant in eutrophic ponds; 5) under environmental stress conditions, submerged macrophytes, phyto-plankton and zooplankton are vulnerable, and the population structure is easy to change and re-place.