Remarkable amphibian biomass and abundance in an isolated wetland: Implications for wetland conservation
Remarkable amphibian biomass and abundance in an isolated wetland: Implications for wetland conservation
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DOI：
10.1111/j.1523-1739.2006.00443.x
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发表时间：
2006-10-01
影响因子：
6.3
通讯作者：
Rothermel, Betsie B.
中科院分区：
文献类型：
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作者：
Gibbons, J. Whitfield;Winne, Christopher T.;Rothermel, Betsie B.
尽管湿地栖息地的持续丧失和两栖动物种群的相关下降，将湿地的损失转化为对生态系统的可衡量的损失的尝试一直很少。我们估计了两栖动物群落的潜在生产力将因失去一片孤立的湿地而受到影响，在过去的54年里，这片湿地一直受到保护，不受大多数工业、农业和城市的影响。在美国南卡罗来纳州艾肯附近的萨凡纳河湿地上，我们使用了埃伦顿湾的连续漂流栅栏，这是一个10公顷的淡水湿地，在长期干旱后对所有两栖动物进行了为期一年的采样。尽管在1951年之前，埃伦顿湾周围的土地得到了密集的农业利用，但我们记录了24种幼年两栖动物(>；36万只；>；1400公斤)在一个繁殖季节产生的数量和生物量。无尾两栖类(17种)比火蜥蜴(7种)更丰富，占个体捕获量的96.4%。大部分(95.9%)两栖动物生物量来自一种无尾两栖动物(南豹蛙/蝶头蛙)的232095只个体。我们的结果揭示了两栖动物群落对自然应激源和历史生境变化的适应能力，以及从孤立的湿地到周围陆地生境的生物量和能量转移的潜在规模。我们将两栖动物在干旱后的成功归因于成虫寿命(通常为5年)、捕食者丰度的减少和幼虫食物资源的丰富。同样，埃伦顿湾周围的森林覆盖率从1951年的20%增加到2001年的60%，这可能是该地点两栖动物长期存在的原因。我们的发现通过证明保护努力可以缓解历史上的栖息地退化，为全球生物多样性下降的问题提供了一个乐观的对立面。
Despite the continuing loss of wetland habitats and associated declines in amphibian populations, attempts to translate wetland losses into measurable losses to ecosystems have been lacking. We estimated the potential productivity from the amphibian community that would be compromised by the loss of a single isolated wetland that has been protected from most industrial, agricultural, and urban impacts for the past 54 years. We used a continuous drift fence at Ellenton Bay, a 10-ha freshwater wetland on the Savannah River Site, near Aiken, South Carolina (U.S.A.), to sample all amphibians for 1 year following a prolonged drought. Despite intensive agricultural use of the land surrounding Ellenton Bay prior to 1951, we documented 24 species and remarkably high numbers and biomass of juvenile amphibians (> 360,000 individuals; > 1,400 kg) produced during one breeding season. Anurans (17 species) were more abundant than salamanders (7 species), comprising 96.4% of individual captures. Most (95.9%) of the amphibian biomass came from 232095 individuals of a single species of anuran (southern leopard frog/Rana sphenocephalal). Our results revealed the resilience of an amphibian community to natural stressors and historical habitat alteration and the potential magnitude of biomass and energy transfer from isolated wetlands to surrounding terrestrial habitat We attributed the postdrought success of amphibians to a combination of adult longevity (often > 5 years), a reduction in predator abundance, and an abundance of larval food resources. Likewise, the increase of forest cover around Ellenton Bay from < 20% in 1951 to > 60% in 2001 probably contributed to the longterm Persistence of amphibians at this site. Our findings provide an optimistic counterpoint to the issue of the global decline of biological diversity by demonstrating that conservation efforts can mitigate historical habitat degradation.