Imperial College, Silwood Park, Ascot, Berkshire SL5 7PY, UK.
Ecol Lett. 2011 Dec;14(12):1246-53. doi: 10.1111/j.1461-0248.2011.01694.x. Epub 2011 Oct 23.
The importance of invertebrate herbivores in regulating plant communities remains unclear, due to the absence of long-term exclusion experiments. An experiment in an English grassland involving long-term exclusions of insect and mollusc herbivores, along with rabbit fencing, showed strong, but opposing, effects of the invertebrate herbivores. Plant species richness declined and biomass increased following insect exclusion, due to increased dominance by a grass species, whereas mollusc exclusion led to increased herbs abundance. The two herbivores had a compensatory interaction: molluscs had no effects in the absence of insects and large insect effects depended on the absence of molluscs. The effects of invertebrate exclusion became apparent only after 8 years, and would have been seriously underestimated in shorter studies. Our results suggest that theorists and conservation managers need to shift from their historic focus on vertebrate herbivory, to a recognition that invertebrates can be equally important drivers of plant community structure.
由于缺乏长期的排除实验，无脊椎草食动物在调节植物群落方面的重要性仍不清楚。在英国的一个草原实验中，通过长期排除昆虫和软体动物草食动物，并加上兔子围栏，显示出无脊椎草食动物具有强烈但相反的影响。昆虫排除后，植物物种丰富度下降，生物量增加，这是由于一种草种的优势增加所致，而软体动物排除则导致草本植物丰度增加。这两种草食动物具有补偿性相互作用：在没有昆虫的情况下，软体动物没有影响，而昆虫的大影响则取决于没有软体动物。无脊椎动物排除的影响仅在 8 年后才变得明显，如果研究时间较短，这些影响将被严重低估。我们的结果表明，理论家和保护管理者需要从他们对脊椎动物食草性的历史关注转移到认识到无脊椎动物同样可以成为植物群落结构的重要驱动因素。
