| 摘要: |
| 浮游植物种类组成细胞密度或生物量的现存量反映其在水生生态系统的结构与功能,准确地对水体中浮游植物进行定量是水质评价和生态功能分析的基础.针对目前国际上推荐使用的倒置显微镜法(即Uterm hl计数法),通过采集处于不同营养状态和水体条件(水库和实验围隔)中的浮游植物,分析样品的显微计数量、水体营养状态对浮游植物密度和多样性等指标稳定性的影响,同时比较了多个水体中同一采样点的重复(或平行)样品之间浮游植物定量数据的差别,从而对倒置显微镜法进行较为系统的评估.结果表明,基于浮游植物的显微镜计数效率与定量数据稳定性的综合考虑,选择计数400个个体即可基本保证定量数据的稳定性;在依赖生物量或稀有种进行水质评价时,处于不同营养水平的水体均需要增加样品的平行数来提高定量数据的可靠性,贫营养型水体中单个采样的重复或平行样品更为必要;两种定量方法所得群落数据计算的辛普森指数无显著差异,说明两种方法所获得结果均能反映浮游植多样性;通过样品浓缩法和倒置显微镜法所获得的浮游植物生物量和细胞密度均具有显著差异,因样品浓缩法在样品处理过程中造成浮游植物损失,使通过样品浓缩法所得的浮游植物群落生物量及细胞密度偏小;相比浓缩法,倒置显微镜法沉淀浓缩的水样体积小,样品处理和计数耗时短,更适宜用于应急监测. |
| 关键词: 浮游植物 倒置显微镜计数 细胞密度 生物量 多样性 |
| DOI：10.18307/2016.0116 |
| 分类号: |
| 基金项目:水利部河湖健康评估广东省试点项目(2013001)和国家自然科学基金项目(U0733007)联合资助. |
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| Data quality analysis of phytoplankton counted with the inverted microscopy-based method |
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NIU Haiyu1, XIAO Lijuan1,2, HAN Boping1,2
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1.Department of Ecology, Jinan University, Guangzhou 510632, P. R. China;2.Guangdong Center for Protection and Control of Cyanobacterial Blooms in Reservoirs, Guangzhou 510632, P. R. China
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| Abstract: |
| Phytoplankton standing stock largely characterizes the structure and function of aquatic ecosystems and thus, it needs to be well quantified for measuring the ecological function. Inverted microscopy method (i.e. Uterm hl's counting method) has been widely applied, but not in developing countries limited by investment for inverted microscopy. Phytoplankton samples collected from three reservoirs with distinct trophic states and three treatments of experimental enclosures were used to demonstrate data quality in using the method. The potential effects of the counting individual and cell abundance, community biomass and cell density in replicates of water samples on the data quality were statistically analyzed. As suggested in the original method by Lund (1958), counting 400 individuals for each plate of meso-and eutrophic water sample is required to balance the stability of data, but we found counting 500 individuals for oligotrophic water is needed. When collecting replicate water samples is possible, especially those used for assessing the water quality, three or five replicates of water samples are strongly suggested to be collected to reduce the standard deviation, especially in oligotrophic water. There was no significant difference in Simpson index between two quantitative methods, indicating that both methods have resulted in a similar measurement of phytoplankton diversity. There were significant differences in both measured biomass and cell density between the two methods because of cells loss during concentrating samples. Compared to the concentrated water sample-based method, inverted microscopy method takes a shorter total time for counting and sedimentation, and is preferred for use in the emergency monitoring. |
| Key words: Phytoplankton Utermöhl method cell density biomass richness |
