CBMA - Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, Campos de Gualtar, 4710-057 Braga, Portugal; CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Rua dos Bragas 289, P 4050-123 Porto, Portugal.
CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Rua dos Bragas 289, P 4050-123 Porto, Portugal.
Sci Total Environ. 2015 Dec 15;538:664-71. doi: 10.1016/j.scitotenv.2015.08.106. Epub 2015 Aug 29.
Resource pulses are episodes of low frequency, large magnitude and short duration that result in increased resource availability in space and time, with consequences for food web dynamics. Studies assessing the importance of resource pulses by invasive alien species in the interface between terrestrial and aquatic ecosystems are rare, especially those in the direction from water to land. This study assessed the importance of massive die-offs of the Asian clam Corbicula fluminea (Müller, 1774) as a resource pulse to the terrestrial invertebrate community after an extreme climatic event using a manipulative experiment. We used 5 levels of C. fluminea density (0, 100, 500, 1000 and 2000ind·m(-2)), with terrestrial invertebrates being censused 7, 30 and 90days after C. fluminea addition. We also assessed the possible effect of plots position, where plots that delimited the experiment were assigned as edge plots and the remaining as core plots. Clear differences were detected in abundance, biomass, richness and diversity of terrestrial invertebrates depending on the C. fluminea density, time and position. Interestingly, the highest abundance of adult Diptera was observed 7days after C. fluminea addition, whereas that of the other terrestrial invertebrates was on day 30, both with C. fluminea densities higher than 500ind·m(-2) located on the edge of the experimental design. This study highlights the importance of major resource pulses after massive die-offs of invasive bivalves, contributing with remarkable amounts of carrion for adjacent terrestrial systems. Part of this carrion can be consumed directly by a great number of invertebrate species while the remainder can enter the detrital food web. Given the high density and biomass attained by several invasive bivalves worldwide and the predicted increase in the number, intensity and magnitude of extreme climatic events, the ecological importance of this phenomenon should be further investigated.
资源脉冲是指低频、大振幅、短持续时间的事件，导致空间和时间内资源可用性增加，对食物网动态产生影响。评估入侵外来物种在陆地和水生生态系统界面中资源脉冲重要性的研究很少，特别是从水到陆地的方向。本研究使用操纵实验评估了极端气候事件后，亚洲淡水贻贝（Corbicula fluminea）大量死亡作为资源脉冲对陆地无脊椎动物群落的重要性。我们使用了 5 个贻贝密度水平（0、100、500、1000 和 2000ind·m(-2))，在贻贝添加后 7、30 和 90 天对陆地无脊椎动物进行了普查。我们还评估了实验位置可能产生的影响，其中实验边界划定的区域为边缘区域，其余为核心区域。陆地无脊椎动物的丰度、生物量、丰富度和多样性根据贻贝密度、时间和位置存在明显差异。有趣的是，在贻贝添加后 7 天观察到成虫双翅目昆虫的最高丰度，而其他陆地无脊椎动物的丰度则在第 30 天观察到，两者均在边缘区域的实验设计中，贻贝密度高于 500ind·m(-2)。本研究强调了入侵双壳类动物大量死亡后主要资源脉冲的重要性，为邻近陆地系统提供了大量腐肉。其中一部分腐肉可以直接被大量无脊椎动物物种消耗，而其余部分可以进入碎屑食物链。鉴于全球范围内几种入侵双壳类动物的高密度和生物量，以及极端气候事件的数量、强度和幅度预计会增加，这种现象的生态重要性应该进一步研究。
