Effects of exotic plant invasions on soil nutrient cycling processes [Review]

Ehrenfeld JG

摘要

Although it is generally acknowledged that invasions by exotic plant species represent a major threat to biodiversity and ecosystem stability, little attention has been paid to the potential impacts of these invasions on nutrient cycling processes in the soil. The literature on plant-soil interactions strongly suggests that the introduction of a new plant species, such as an invasive exotic, has the potential to change many components of the carbon (C), nitrogen (N), water, and other cycles of an ecosystem. I have reviewed studies that compare pool sizes and flux rates of the major nutrient cycles in invaded and noninvaded systems for invasions of 56 species. The available data suggest that invasive plant species frequently increase biomass and net primary production, increase N availability, alter N fixation rates, and produce litter with higher decomposition rates than co-occurring natives. However, the opposite patterns also occur, and patterns of difference between exotics and native species show no trends in some other components of nutrient cycles (for example, the size of soil pools of C and N). In some cases, a given species has different effects at different sites, suggesting that the composition of the invaded community and/or environmental factors such as soil type may determine the direction and magnitude of ecosystem-level impacts. Exotic plants alter soil nutrient dynamics by differing from native species in biomass and productivity, tissue chemistry, plant morphology, and phenology. Future research is needed to (a) experimentally test the patterns suggested by this data set; (b) examine fluxes and pools for which few data are available, including whole-site budgets; and (c) determine the magnitude of the difference in plant characteristics and in plant dominance within a community that is needed to alter ecosystem processes. Such research should be an integral component of the evaluation of the impacts of invasive species.

机译：尽管人们普遍认为外来植物物种的入侵是对生物多样性和生态系统稳定性的主要威胁，但很少有人关注这些入侵对土壤养分循环过程的潜在影响。有关植物与土壤相互作用的文献强烈建议，引入一种新的植物物种（例如外来入侵物种），有可能改变碳（C），氮（N），水和植物其他循环中的许多成分。生态系统。我已经审查了比较入侵和非入侵系统中56种入侵物种的主要养分循环的库大小和通量速率的研究。现有数据表明，入侵植物物种经常增加生物量和净初级生产力，增加氮素的利用，改变氮素固定率，并且产生的凋落物的分解率要高于共生本地植物。但是，相反的模式也会发生，外来物种和本地物种之间的差异模式在养分循环的其他某些部分（例如，碳和氮的土壤库的大小）中没有任何趋势。在某些情况下，给定物种在不同地点具有不同的影响，这表明被入侵的群落组成和/或环境因素（例如土壤类型）可能决定生态系统影响的方向和程度。外来植物通过改变生物量和生产力，组织化学，植物形态和物候等方面与天然物种的土壤养分动态。需要进行进一步的研究，以（a）实验测试此数据集建议的模式; （b）检查流量和流量池，其中几乎没有可用数据，包括整个站点的预算; （c）确定改变生态系统过程所需的社区内植物特征和植物优势方面差异的大小。这类研究应成为评估入侵物种影响的组成部分。

Effects of exotic plant invasions on soil nutrient cycling processes [Review]

摘要

著录项

相关主题

期刊订阅