Contrasting impacts of invasive engineers on freshwater ecosystems: an experiment and meta-analysis
Contrasting impacts of invasive engineers on freshwater ecosystems: an experiment and meta-analysis
复制标题
DOI：
10.1007/s00442-008-1180-1
复制
发表时间：
2009-01-01
期刊：
影响因子：
2.7
通讯作者：
Washitani, Izumi
中科院分区：
文献类型：
--
作者：
Matsuzaki, Shin-ichiro S.;Usio, Nisikawa;Washitani, Izumi
鲤鱼和克氏原螯虾入侵浅水湖泊后，由水生植物主导的清水状态向植物浮游生物主导的浊水状态发生稳定的变化。因此，入侵的鲤鱼和小龙虾都可能是灾难性政权转变的驱动因素。尽管这两个物种已经被引入到世界各地的生态系统中，但它们对政权转变的相对重要性仍然没有得到充分的研究。采用围隔实验和荟萃分析相结合的方法，比较了鲤鱼和螯虾对沉水植物、水质、浮游植物、营养盐动态、浮游动物和底栖大型无脊椎动物的生态影响。该实验旨在研究水质和生物变量如何对鲤鱼或小龙虾生物量的增加作出反应。我们发现，即使在低生物量，鲤鱼有大的和积极的影响，悬浮固体，浮游植物和营养物质和底栖大型无脊椎动物的负面影响。相反，小龙虾对沉水植物有很强的负面影响。淡水螯虾对水生植物的影响显著大于鲤鱼。结果表明，鲤鱼和螯虾对沉水植物、浮游植物、营养盐动态和底栖大型无脊椎动物均有显著影响，但对浮游动物影响较小。这也表明，相对于鲤鱼，小龙虾对水生植物的影响显著更大。总体而言，荟萃分析在很大程度上支持了实验结果。作为一个整体，我们的研究结果表明，鲤鱼和小龙虾通过生物扰动，排泄，消费和非消费性破坏的综合后果对群落组成和生态系统过程产生深远的影响。然而，关键变量（e。G.与稳定状态变化有关的水生植物（包括大型植物）对鲤鱼或小龙虾生物量的增加作出不同的反应，表明它们对生态系统的影响不同。
Invasion by common carp (Cyprinus carpio) and red swamp crayfish (Procambarus clarkii) in shallow lakes have been followed by stable-state changes from a macrophyte-dominated clear water state to a phytoplankton-dominated turbid water state. Both invasive carp and crayfish are, therefore, possible drivers for catastrophic regime shifts. Despite these two species having been introduced into ecosystems world-wide, their relative significance on regime shifts remains largely unexplored. We compared the ecological impacts of carp and crayfish on submerged macrophytes, water quality, phytoplankton, nutrient dynamics, zooplankton and benthic macroinvertebrates by combining an enclosure experiment and a meta-analysis. The experiment was designed to examine how water quality and biological variables responded to increasing carp or crayfish biomass. We found that even at a low biomass, carp had large and positive impacts on suspended solids, phytoplankton and nutrients and negative impacts on benthic macroinvertebrates. In contrast, crayfish had a strong negative impact on submerged macrophytes. The impacts of crayfish on macrophytes were significantly greater than those of carp. The meta-analysis showed that both carp and crayfish have significant effects on submerged macrophytes, phytoplankton, nutrient dynamics and benthic macroinvertebrates, while zooplankton are affected by carp but not crayfish. It also indicated that crayfish have significantly greater impacts on macrophytes relative to carp. Overall, the meta-analysis largely supported the results of the experiment. Taken as a whole, our results show that both carp and crayfish have profound effects on community composition and ecosystem processes through combined consequences of bioturbation, excretion, consumption and non-consumptive destruction. However, key variables (e. g. macrophytes) relating to stable-state changes responded differently to increasing carp or crayfish biomass, indicating that they have differential ecosystem impacts.