School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia.
School of Ecosystem and Forest Sciences, The University of Melbourne, Parkville, VIC, 3010, Australia.
Conserv Biol. 2019 Apr;33(2):389-402. doi: 10.1111/cobi.13210. Epub 2018 Nov 27.
Urban sprawl and the rising popularity of water-sensitive urban design of urban landscapes has led to a global surge in the number of wetlands constructed to collect and treat stormwater runoff in cities. However, contaminants, such as heavy metals and pesticides, in stormwater adversely affect the survival, growth, and reproduction of animals inhabiting these wetlands. A key question is whether wildlife can identify and avoid highly polluted wetlands. We investigated whether pond-breeding frogs are attempting to breed in wetlands that affect the fitness of their offspring across 67 urban wetlands in Melbourne, Australia. Frog species richness and the concentration of contaminants (heavy metals and pesticides) were not significantly related, even in the most polluted wetlands. The proportion of fringing vegetation at a wetland had the greatest positive influence on the number of frog species present and the probability of occurrence of individual species, indicating that frogs inhabited wetlands with abundant vegetation, regardless of their pollution status. These wetlands contained contaminant levels similar to urban wetlands around the world at levels that reduce larval amphibian survival. These results are, thus, likely generalizable to other areas, suggesting that urban managers could inadvertently be creating ecological traps in countless cities. Wetlands are important tools for the management of urban stormwater runoff, but their construction should not facilitate declines in wetland-dependent urban wildlife.
城市扩张和水敏性城市景观设计的日益普及，导致全球范围内为收集和处理城市雨水径流而建造的湿地数量激增。然而，雨水径流中的污染物，如重金属和农药，会对栖息在这些湿地中的动物的生存、生长和繁殖产生不利影响。一个关键问题是野生动物是否能够识别和避免污染严重的湿地。我们调查了在澳大利亚墨尔本的 67 个城市湿地中，是否有pond-breeding 青蛙试图在影响其后代健康的湿地中繁殖。尽管在污染最严重的湿地中，青蛙物种的丰富度与污染物（重金属和农药）的浓度没有显著的关系。湿地边缘植被的比例对存在的青蛙物种数量和个别物种出现的概率有最大的积极影响，这表明青蛙栖息在植被丰富的湿地中，而不管其污染状况如何。这些湿地的污染物含量与世界各地的城市湿地相似，这些污染物含量会降低幼体两栖动物的存活率。因此，这些结果可能在其他地区具有普遍性，这表明城市管理者可能在无意中为无数城市创造了生态陷阱。湿地是管理城市雨水径流的重要工具，但它们的建设不应促进依赖湿地的城市野生动物的减少。
