Lee Tammy A, Rollwagen-Bollens Gretchen, Bollens Stephen M
School of the Environment, Washington State University, 14204 NE Salmon Creek Avenue, Vancouver, WA, 98686, USA,
Environ Monit Assess. 2015 Jun;187(6):315. doi: 10.1007/s10661-015-4550-2. Epub 2015 May 4.
Cyanobacterial blooms and their detrimental effects on water quality have become a worldwide problem. Vancouver Lake, a tidally influenced shallow temperate freshwater lake in Washington state, U.S.A., exhibits annual summer cyanobacterial blooms that are of concern to local resource managers. Our objectives were to describe changes in phytoplankton community composition in Vancouver Lake over seasonal, annual, and interannual time scales, and to identify strong water quality predictors of phytoplankton community structure, with an emphasis on cyanobacterial blooms, from 2007 through 2010. Cluster analysis, indicator species analysis, and non-metric multidimensional scaling were used to identify significantly different phytoplankton community groupings and to determine which environmental factors influenced community changes. From 2007 through 2009, depletion of NO3-N followed by elevated PO4-P concentration was associated with increased biomass and duration of each cyanobacterial bloom. Time-lag analysis suggested that NO3-N availability contributed to interannual changes within the summer phytoplankton community. Specifically, in summer 2010, a distinct cyanobacteria community was not present, potentially due to increased NO3-N and decreased PO4-P and NH4-N availability. Our study provides a comprehensive assessment of species-level responses to water quality variables in a shallow non-stratifying temperate lake, contributes to a better understanding of phytoplankton dynamics, and may aid in predicting and managing cyanobacterial blooms.
蓝藻水华及其对水质的有害影响已成为一个全球性问题。美国华盛顿州的温哥华湖是一个受潮汐影响的浅温带淡水湖，每年夏季都会出现蓝藻水华，这引起了当地资源管理者的关注。我们的目标是描述2007年至2010年期间温哥华湖浮游植物群落组成在季节、年度和年际时间尺度上的变化，并确定浮游植物群落结构的强大水质预测因子，重点是蓝藻水华。聚类分析、指示物种分析和非度量多维标度法被用于识别显著不同的浮游植物群落分组，并确定哪些环境因素影响了群落变化。从2007年到2009年，NO3-N的消耗随后是PO4-P浓度的升高与每次蓝藻水华的生物量增加和持续时间延长有关。时间滞后分析表明，NO3-N的可用性促成了夏季浮游植物群落的年际变化。具体而言，在2010年夏季，没有出现明显的蓝藻群落，这可能是由于NO3-N增加以及PO4-P和NH4-N可用性降低所致。我们的研究对一个浅的非分层温带湖泊中物种对水质变量的响应进行了全面评估，有助于更好地理解浮游植物动态，并可能有助于预测和管理蓝藻水华。
