Direct and indirect effects of shrub encroachment on alpine grasslands mediated by plant-flower visitor interactions

Mutualistic interactions structure ecological communities and they are strongly influenced by the combined effect of different drivers of global change. Land-use changes and global warming have elicited rapid shrub encroachment in alpine grasslands in recent decades, which may have detrimental outcomes for native alpine forbs. In spite of the importance of this process, we lack knowledge about how shrub encroachment modifies community-wide patterns of plant–pollinator mutualistic interactions. Based on the functional biodiversity hypothesis (FBH), which predicts higher pollinator biodiversity in species-rich plant communities, we asked whether the increase in nutritional resources available for pollinators due to shrub expansion modifies pollinator niche breadth and species richness, and whether these changes affect plant–plant interactions. For this purpose, we compared quantitative plant–flower visitor interaction network assemblages at replicated plots in two habitat types in d...互利共生相互作用塑造生态群落结构，且深受全球变化不同驱动因子共同作用的强烈影响。近数十年来，土地利用变化与全球变暖导致高山草原出现了快速的灌木灌丛化现象，这可能对本土高山非禾本科草本植物造成不利影响。尽管该过程意义重大，但目前我们仍缺乏关于灌木灌丛化如何改变植物-传粉者互利共生相互作用的群落尺度格局的认知。 基于功能生物多样性假说（FBH）——该假说预测物种丰富的植物群落中拥有更高的传粉者生物多样性——我们开展了两项科学探究：其一，灌木扩张为传粉者带来的可利用营养资源增加，是否会改变传粉者的生态位宽度与物种丰富度；其二，此类变化是否会影响植物间的相互作用。 为此，我们针对两类生境的重复样地中的定量植物-访花者互作网络群落进行了对比分析，研究区域位于……