英德西南旅游区水源河流水质与浮游生物群落特征

Water quality and plankton in the water-sources river Population in scenic spots southwest of Yingde city

通过野外采样及实验室分析,调查了英德市西南旅游区水源河流上、中、下游的水质状况及浮游生物的多样性。结果表明,(1)英德市西南旅游区上、中、下游河段亚硝酸盐、氨、硝酸盐、总氮、镉、铅、铬、镍、铜、锌的含量低于国家标准,铝、钙、钴、铁、钼、硒的含量超过国家标准,而总磷、砷、镁、锰的含量在部份区段已超过国家标准;(2)浮游动物种类的个体数在整条河中以桡足类最多,上游通天岩中浮游动物个体数最多,下游碧落湖浮游动物多样性最低;此次调查总共发现68种浮游植物,其中主要集中在下游碧落湖,在中游碧落洞绿藻、蓝藻、硅藻总个体数最低,上游通天岩绿藻及甲藻总个体数最多,而下游碧落湖的蓝藻和硅藻的总个体数最多;(3)总氮、总磷、铅、钙、浮游动物Shannon-Weaver指数与浮游植物Shannon-Weaver指数从上游向下游增加,而锰与镍含量则成相反趋势。文中探讨了水中元素之间、元素与生物之间、浮游动植物之间的相互关系。本文对风景区水源的生态环境的研究风景区旅游资源开发与管理提供参考。

Using field and laboratory approaches, the water quality and biodiversity of plankton of in upper reaches, middle reaches, and lower reaches in the river taken as sources of water in scenic spots southwest of Yingde, China were investigated, with the aim to evaluate the spatial properties of hydro-ecological factors and the relationships between chemical parameters and plankton dynamics in different sections of the river. The concentations of phosphate, total phosphorus, nitrite, ammonia, nitrate, total inorganic nitrogen, and total nitrogen, heavy metals of aluminum, arsenic, cadmium, lead, copper, and zinc, and trace elements of calcium, cobalt, chromium, iron, magnesium, manganese, molybdenum, nickel, and selenium were measured, Population densities, species composition, and biodiversity index of phytoplankton and zooplankton were also examined. The levels of nitrite, ammonia, nitrate, total nitrogen, cadmium, lead, chromium, nickel, copper, and zinc in all sections of the river were within the environmental quality standard of surface water or sanitary standard for drinking water, but those of aluminum, calcium, cobalt, iron, molybdenum, and selenium in all sections of the river and those of total phosphorus, arsenic, magnesium, and manganese in some sections of the river exceeded the standards. Copepods were the dominant zooplankton in all sections of the river. The highest population density of zooplankton was in the section of Tongtianyan, the upper river reach, and the lowest biodiversity index of zooplankton was in the section of Biluohu, the lower river reach. 68 species of phytoplankton were found in the river, most of them inhabiting in the section of Biluohu. Population densities of chlorophyte, cyanophyte, and diatom were the lowest in the section of Biluodong, the middle river reach, those of chlorophyte and dinoflagellate were highest in the section of Tongtianyan, and those of cyanophyte and diatom were highest in the section of Biluohu. Along to the spatial trend from the upper reaches to the lower reaches, the concentrations of total phosphorus, total nitrogen, aluminum, and calcium and Shannon-Weaver biodiversity index of zooplankton increased, but the contents of manganese and nickel decreased. The relationships between chemical parameters and plankton were addressed. Results suggested that the water in the river studied should not be drunk directly, but it could be taken as the water in the landscape that should not be touched by people. This paper improved our understanding of the ecological structure and function of water-sources rivers in landscape, and can provide basic information for further managements of this ecosystem.