Zhu Hui, Zou Xuehui, Wang Deli, Wan Shiqiang, Wang Ling, Guo Jixun
Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun, Jilin 130024, China.
School of Life Sciences, Northeast Normal University, Changchun, Jilin 130024, China.
Sci Rep. 2015 Dec 21;5:18654. doi: 10.1038/srep18654.
Climate warming may disrupt trophic interactions, consequently influencing ecosystem functioning. Most studies have concentrated on the temperature-effects on plant-insect interactions at individual and population levels, with a particular emphasis on changes in phenology and distribution. Nevertheless, the available evidence from the community level is limited. A 3-year field manipulative experiment was performed to test potential responses of plant and insect communities, and plant-insect interactions, to elevated temperature in a meadow steppe. Warming increased the biomass of plant community and forbs, and decreased grass biomass, indicating a shift from grass-dominant to grass-forb mixed plant community. Reduced abundance of the insect community under warming, particularly the herbivorous insects, was attributed to lower abundance of Euchorthippus unicolor and a Cicadellidae species resulting from lower food availability and higher defensive herbivory. Lower herbivore abundance caused lower predator species richness because of reduced prey resources and contributed to an overall decrease in insect species richness. Interestingly, warming enhanced the positive relationship between insect and plant species richness, implying that the strength of the plant-insect interactions was altered by warming. Our results suggest that alterations to plant-insect interactions at a community level under climate warming in grasslands may be more important and complex than previously thought.
气候变暖可能会扰乱营养级相互作用，从而影响生态系统功能。大多数研究都集中在温度对个体和种群水平上植物与昆虫相互作用的影响，尤其关注物候和分布的变化。然而，来自群落水平的现有证据有限。我们进行了一项为期3年的田间操纵实验，以测试草甸草原中植物和昆虫群落以及植物 - 昆虫相互作用对温度升高的潜在响应。变暖增加了植物群落和草本植物的生物量，降低了禾本科植物的生物量，这表明从以禾本科植物为主的植物群落转变为禾本科 - 草本混合植物群落。变暖条件下昆虫群落数量减少，尤其是食草昆虫，这归因于由于食物供应减少和防御性食草作用增强导致的单色异爪蝗和一种叶蝉科物种数量减少。食草动物数量减少导致捕食者物种丰富度降低，原因是猎物资源减少，这导致昆虫物种丰富度总体下降。有趣的是，变暖增强了昆虫和植物物种丰富度之间的正相关关系，这意味着变暖改变了植物 - 昆虫相互作用的强度。我们的结果表明，在气候变暖条件下，草原群落水平上植物 - 昆虫相互作用的改变可能比以前认为的更为重要和复杂。
