关键词: 全球变化, 种间关系, 食物网结构, 物候错配, 关键种丧失, 生物入侵

Abstract: The food web sustains its structure mainly by bottom-up and top-down controls, which are based on the interactions between species at different trophic levels. However, global changes can alter interspecific relationships and threaten the maintenance of biodiversity, but it is still unclear how global change alters the structure of the food webs. In recent years, based on numerous studies on food webs composed of multi-trophic levels at large spatiotemporal scales, researchers have found that global changes alter food web structure mainly through three mechanisms: phenological mismatching, loss of key species and biological invasion. Here we focused on these three mechanisms and reviewed how these mechanisms change food web structure change, with further discussion on the driving factors in ecology and evolution. All these three mechanisms can alter the interspecific interactions, resulting in distortion of the regulation of food webs. The major difference among these three mechanisms is how interspecific interactions are changed. Phenological mismatching occurs due to the asynchronous responses in the phenology of different species to global changes, while the loss of key species can change or even entirely destroys some critical feeding/predation relationships, and invasive species often simplify the food web structure by causing strong interspecific competition to exclude species at the same trophic level. Finally, we addressed that the changes in food web structure depends on the adaptation of species to the ongoing global changes and provided some insights into future researches. As the impacts of global changes are increasingly aggravating, it is necessary to further study the mechanisms how global changes influence food web structure, to reinforce the extant theoretical basis for improvements in the strategies of biodiversity conservation and ecological restoration.

Key words: global changes, interspecific interactions, food web structure, phenological mismatching, loss of keystone species, biological invasion