De Little Siobhan C, Bowman David M J S, Whelan Peter I, Brook Barry W, Bradshaw Corey J A
Environment Institute, School of Earth and Environmental Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
Environ Entomol. 2009 Aug;38(4):1013-21. doi: 10.1603/022.038.0408.
Understanding the contributions of environmental variation and density feedbacks to changes in vector populations is essential for designing effective vector control. We analyzed monitoring datasets describing larval densities over 7 yr of the two dominant mosquito species, Aedes vigilax (Skuse) and Culex annulirostris (Skuse), of the greater Darwin area (Northern Territory, Australia). Using generalized linear and linear mixed-effects models, we tested hypotheses regarding the environmental determinants of spatio-temporal patterns in relative larval abundance in both species. The most important spatial drivers of Ae. vigilax and Cx. annulirostris larval densities were elevation and water presence. Ae. vigilax density correlates negatively with elevation, whereas there was a positive relationship between Cx. annulirostris density and elevation. These results show how larval habitats used by the saltwater-influenced breeder Ae. vigilax and the obligate freshwater breeder Cx. annulirostris are separated in a tidally influenced swamp. The models examining temporal drivers of larval density also identified this discrimination between freshwater and saltwater habitats. Ae. vigilax larval densities were positively related to maximum tide height and high tide frequency, whereas Cx. annulirostris larval densities were positively related to elevation and rainfall. Adult abundance in the previous month was the most important temporal driver of larval densities in both species, providing a clear dynamical link between the two main life phases in mosquito development. This study shows the importance of considering both spatial and temporal drivers, and intrinsic population dynamics, when planning vector control strategies to reduce larval density, adult population density, and disease transmission effectively.
了解环境变化和密度反馈对病媒种群变化的影响，对于设计有效的病媒控制措施至关重要。我们分析了监测数据集，这些数据集描述了澳大利亚北领地达尔文大区两种主要蚊子物种——刺扰伊蚊（Skuse）和环纹库蚊（Skuse）——7年期间的幼虫密度。我们使用广义线性模型和线性混合效应模型，检验了关于这两种物种相对幼虫丰度时空格局的环境决定因素的假设。刺扰伊蚊和环纹库蚊幼虫密度最重要的空间驱动因素是海拔和积水情况。刺扰伊蚊密度与海拔呈负相关，而环纹库蚊密度与海拔呈正相关。这些结果表明，受盐水影响的繁殖者刺扰伊蚊和专性淡水繁殖者环纹库蚊所利用的幼虫栖息地，在受潮汐影响的沼泽中是如何分隔的。研究幼虫密度时间驱动因素的模型也确定了淡水和咸水栖息地之间的这种差异。刺扰伊蚊幼虫密度与最大潮高和涨潮频率呈正相关，而环纹库蚊幼虫密度与海拔和降雨量呈正相关。前一个月的成虫丰度是这两种物种幼虫密度最重要的时间驱动因素，这在蚊子发育的两个主要生命阶段之间建立了明确的动态联系。这项研究表明，在规划病媒控制策略以有效降低幼虫密度、成虫种群密度和疾病传播时，考虑空间和时间驱动因素以及内在种群动态的重要性。
