The bio-indicator role of wintering waterbirds in littoral zone of Lake Erhai, Yunnan Province

Abstract

水鸟在物种或群落水平上可以对湿地营养状态有所响应，预警生态系统有害的改变. 以大型淡水湖泊洱海为例，基于2015年2月沿岸17个观察点的冬季水鸟调查与水质同步监测，研究小（Podiceps ruficollis）、白骨顶（Fulica atra）和黑水鸡（Gallinula chloropus）密度对沿岸水体中总磷和总氮浓度的响应关系. 结果发现白骨顶和小密度均与总氮浓度呈显著正相关，也均与总磷浓度呈显著正相关；黑水鸡密度与总氮和总磷浓度无显著相关性. 结果表明，水鸟可以在物种水平上对洱海湖滨带水中营养物质变化有所响应，也强调了根据具体指示物种的生态学习性选择水鸟指示物种尤为重要. 白骨顶和小在更大空间和时间尺度上的水质指示作用有待于更多湖泊或水库水体的长期相关研究.;Waterbirds respond sensitivly to the nutrient change of wetlands in a species-specific or community way, which can provide early warning for changes that could negatively affect ecosystems. We studied the relationship between waterbird density and water quality index among 17 lakeshore sections in Lake Erhai, a large freshwater lake. We counted individual numbers of Little Grebe (Podiceps ruficollis), Common Coot (Fulica atra), Common Moorhen (Gallinula chloropus) and collected water samples synchronously in February 2015. Pearson correlation analysis showed that the population densities of both Common Coot and Little Grebe were significantly correlated to the total nitrogen concentration and the total phosphorus concentration. While the population density of Common Moorhen was not correlated to either the total nitrogen concentration or the total phosphorus concentration. The results suggested that waterbirds could respond to nutrient changes in littoral zone of Lake Erhai in a species-specific way, and a thorough knowledge of the ecology of a given species is required to properly choose a waterbird bio-indicator species. Further studies in more lakes or reservoirs could justify the bio-indicator role of Common Coot and Little Grebe at larger temporal and spatial scales.