Cities are increasingly using constructed ponds to mitigate flooding and downstream water pollution from urban runoff. As a result, these stormwater ponds can have poor water quality, yet they can also attract wildlife. In this study, the effects of water quality on dragonflies and damselflies (Odonata) were determined in stormwater ponds (n = 41) and natural reference ponds (n = 10) of similar size across the National Capital Region of Canada. A total of 38 chemical/physical water quality variables along with Odonata nymph abundance and taxonomic composition were sampled at each pond. Chloride concentrations exceeded the guideline for the protection of aquatic life at over two-thirds of the stormwater ponds. Among all the metals tested, only Cu exceeded guidelines at many stormwater ponds. Both dragonfly and damselfly nymphs were on average less abundant in the stormwater ponds in comparison to the natural ponds. Ponds with high concentrations of chloride and metals typically had lower dragonfly abundance. Dragonfly community structure was significantly influenced by high chloride (or conductivity), which likely originates from winter road salting. In contrast, damselfly community structure in the stormwater ponds was similar to that found in natural ponds, with nutrients and metals explaining a small percent of variation in community structure. A water quality index developed to assess habitats for the protection of aquatic life did not significantly explain Odonata abundance or measures of diversity and may not be suitable in assessing pond habitat quality. To improve pond habitats within cities, efforts should be directed at reducing the amount of impervious surface and road salt usage within catchment basins.

中文翻译：

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水质对蜻蜓和豆娘若虫群落的影响：城市池塘和天然池塘的比较。

城市越来越多地使用人工池塘来减轻洪水和城市径流对下游水的污染。结果，这些雨水池塘的水质可能很差，但它们也可能吸引野生动植物。在这项研究中，确定了加拿大全国首都地区类似大小的雨水池塘（n = 41）和自然参考池塘（n = 10）中水质对蜻蜓和蜻蜓（Odonata）的影响。每个池塘总共采样了38个化学/物理水质变量以及Odonata若虫的丰度和分类学组成。三分之二以上的雨水池塘中的氯化物浓度超过了保护水生生物的准则。在所有测试的金属中，许多雨水池塘中只有Cu超过了标准。与天然池塘相比，在雨水池塘中蜻蜓和豆娘若虫的平均含量较低。氯化物和金属浓度高的池塘通常蜻蜓的丰度较低。蜻蜓的群落结构受到高氯化物（或电导率）的显着影响，这很可能源于冬季道路盐化。相比之下，雨水池塘中的豆娘社区结构与天然池塘中的相似，营养物质和金属说明了社区结构中很小的变化。为评估生境以保护水生生物而开发的水质指数并未显着解释Odonata的丰度或多样性，也可能不适用于评估池塘生境的质量。为了改善城市内的池塘栖息地，