Carver Scott, Spafford Helen, Storey Andrew, Weinstein Philip
School of Animal Biology (M085), University of Western Australia, Crawley, Western Australia, Australia.
Environ Entomol. 2010 Jun;39(3):798-810. doi: 10.1603/EN09235.
Studies that consider both biotic and abiotic determinants of organisms are rare, but critical to delineate underlying determinants of community richness (number of taxa) and abundance (number of larvae per water body). In this study, we consider the importance of disturbance (salinity) and predator and competitor variables on mosquitoes (Diptera: Culicidae) in small ephemeral water bodies across the Wheatbelt of Western Australia. Similar to mosquitoes, and contrary to general perceptions, nonculicid aquatic fauna (aquatic fauna) had a common occurrence (number or percentage of water bodies occupied) and were abundant (average density) in ephemeral water bodies, albeit with a simplified trophic structure. The occurrence and density (number per unit area) of aquatic fauna between water bodies were highly variable, but general relationships of aquatic fauna with rainfall, water body surface area, salinity, and mosquitoes were apparent. In contrast to mosquitoes, the density of aquatic fauna declined with recent rainfall, implying mosquitoes may colonize newly created water bodies more quickly than aquatic fauna. Assemblages (richness and density of taxa) of aquatic fauna changed along a salinity gradient, as did mosquitoes, and this was pronounced for predator groups. Densities of mosquitoes were not limited by any single taxonomic group, by a negative relationship. However, the density and richness of mosquitoes generally declined in association with increased richness of predators and density of all other taxa (taxa not specifically classified as predators or competitors of mosquitoes). These relationships may account for higher densities of mosquitoes in smaller water bodies, where richness of predators is reduced and the density of other taxa does not differ from larger water bodies. Our results also suggest salinity in the Western Australia Wheatbelt may facilitate greater abundance of halotolerant mosquitoes, Aedes alboannulatus Macquart and Aedes camptorhynchus Thomson (a vector of Ross River virus [Togoviridae: Alphavirus]), by releasing them from biotic regulation.
同时考虑生物和非生物因素对生物影响的研究很少见，但对于描绘群落丰富度（分类单元数量）和丰度（每个水体中的幼虫数量）的潜在决定因素至关重要。在本研究中，我们考察了干扰（盐度）以及捕食者和竞争者变量对西澳大利亚小麦带小型临时性水体中蚊子（双翅目：蚊科）的重要性。与蚊子相似，与一般认知相反，非蚊科水生动物群（水生动物）在临时性水体中普遍存在（占据水体的数量或百分比）且数量丰富（平均密度），尽管其营养结构较为简单。不同水体间水生动物的出现情况和密度（每单位面积的数量）差异很大，但水生动物与降雨、水体表面积、盐度和蚊子之间的一般关系是明显的。与蚊子不同，水生动物的密度随着近期降雨而下降，这意味着蚊子可能比水生动物更快地在新形成的水体中定殖。水生动物群的组合（分类单元的丰富度和密度）如同蚊子一样，沿着盐度梯度发生变化，捕食者群体的这种变化尤为明显。蚊子的密度不受任何单一分类群的负相关关系限制。然而，蚊子的密度和丰富度通常会随着捕食者丰富度的增加以及所有其他分类群（未明确归类为蚊子的捕食者或竞争者的分类群）密度的增加而下降。这些关系可能解释了较小水体中蚊子密度较高的原因，在较小水体中，捕食者的丰富度降低，而其他分类群的密度与较大水体并无差异。我们的研究结果还表明，西澳大利亚小麦带的盐度可能通过解除生物调节作用，促进耐盐蚊子白纹伊蚊和弯喙伊蚊（罗斯河病毒[披膜病毒科：甲病毒属]的传播媒介）数量的增加。
