Zooplankton of Small Lakes and Wetland Ponds in Wisconsin - North Temperate Lakes LTER 1996

We sampled zooplankton communities from 54 small water bodies distributed throughout Wisconsin to evaluate whether a snap-shot of zooplankton community structure during early spring could be used for the purpose of differentiating lakes from wetlands. We collected a single set of zooplankton and water chemistry data during a one-month time window (synchronized from south to north across the state) from an open water site in each basin as a means to minimize and standardize sampling effort and to minimize cascading effects arising from predator-prey interactions with resident and immigrant aquatic insect communities. We identified 53 taxa of zooplankton from 54 sites sampled across Wisconsin. There was an average of 6.83 taxa per site. The zooplankton species were distributed with a great deal of independence. We did not detect significant correlations between number of taxa and geographic region or waterbody size. There was a significant inverse correlation between number of taxa and the concentration of calcium ion, alkalinity and conductivity. One pair of taxa, Lynceus brachyurus and Chaoborus americanus, showed a significant difference in average duration of sites of their respective occurrence. All other pairs of taxa had no significant difference in average latitude, waterbody surface area, total phosphorus, total Kjeldahl nitrogen, alkalinity, conductivity, calcium ion, sulfate, nitrate, silicate or chloride. Taxa were distributed at random among the sites - there were no statistically significant pairs of taxa occurring together or avoiding each other. Multivariate analysis of zooplankton associations showed no evidence of distinct associations that could be used to distinguish lakes from wetlands. Zooplankton community structure appears to be a poor tool for distinguishing between lakes and wetlands, especially at the relatively large scale of Wisconsin (dimension of about 500 km). The data suggest that a small body of water in Wisconsin could be classified as a wetland if it persists in the spring and summer for only about 4 months, and if it is inhabited by Lynceus brachyurus, Eubranchipus bundyi, and if Chaoborus americanus and Chydorus brevilabris are absent. Schell, Jeffery M., Carlos J. Santos-Flores, Paula E. Allen, Brian M. Hunker, Scott Kloehn, Aaron Michelson, Richard A. Lillie, and Stanley I. Dodson. 2001. Physical-chemical influences on vernal zooplankton community structure in small lakes and wetlands of Wisconsin, U.S.A. Hydrobiologia 445:37-50 Number of sites: 54

本研究从分布于美国威斯康星州全境的54个小型水体中采集浮游动物（zooplankton）群落样本，旨在探究早春时节浮游动物群落结构的快照式采样数据能否用于区分湖泊与湿地。本研究在为期1个月的时间窗口内（全州范围内自南向北同步开展），于每个水体的敞水采样点采集了一套浮游动物与水体化学数据，以尽可能减少并标准化采样工作量，并最小化由本土及迁入性水生昆虫群落的捕食者-猎物相互作用所引发的级联效应。本次威斯康星州54个采样点共鉴定出53个浮游动物分类单元（taxa），每个采样点平均包含6.83个分类单元，且浮游动物物种的分布独立性较强。未发现分类单元数量与地理区域或水体规模间存在显著相关性。分类单元数量与钙离子浓度、碱度及电导率呈显著负相关关系。一对分类单元——短肢涟虫（Lynceus brachyurus）和美洲幽蚊（Chaoborus americanus）——在各自出现的采样点的平均存续时长上存在显著差异。其余所有分类单元对在平均纬度、水体表面积、总磷、凯氏总氮（total Kjeldahl nitrogen）、碱度、电导率、钙离子浓度、硫酸盐、硝酸盐、硅酸盐或氯化物浓度方面均无显著差异。分类单元在采样点间呈随机分布——未发现存在统计学意义上显著的共现或互斥的分类单元对。对浮游动物群落关联的多变量分析显示，不存在可用于区分湖泊与湿地的显著群落关联模式。浮游动物群落结构似乎并非区分湖泊与湿地的有效工具，尤其在威斯康星州这类约500公里跨度的较大空间尺度下。本研究数据显示，威斯康星州的小型水体若仅在春夏季存续约4个月，且栖息有短肢涟虫（Lynceus brachyurus）、邦迪真鳃足虫（Eubranchipus bundyi），同时不存在美洲幽蚊（Chaoborus americanus）与短唇壳纹溞（Chydorus brevilabris），则可被归类为湿地。参考文献：Schell, Jeffery M.、Carlos J. Santos-Flores、Paula E. Allen、Brian M. Hunker、Scott Kloehn、Aaron Michelson、Richard A. Lillie 及 Stanley I. Dodson. 2001. 美国威斯康星州小型湖泊与湿地春季浮游动物群落结构的理化影响因素. 《Hydrobiologia》445:37-50 采样点数量：54