Robustness Of Metacommunities With Bipartite Networks To Habitat Destruction Based On Competition-Colonization Tradeoffs

Habitat destruction is one of the most important drivers forces of biodiversity loss.Current theoretical and experimental studies mainly focus on the effects of habitat destruction on biodiversity,but little is known about how habitat destruction affects the structure of species interaction networks and its effects on community robustness,particularly the typical mutualistic and antagonistic bipartite networks.Therefore,exploring the relationship between the structural complexity of species interaction network and community robustness in the context of habitat destruction is one of the fundamental issues in ecology.By combining metacommunity theory and modern network theory,this study constructs a multi-species model for trophically-linked metacommunities by patch occupancy dynamic incorporating spatial competition,and then systematically explores the effects of bipartite network structural characteristics(e.g.,network size,connectance,nestedness and modularity)on metacommunities robustness to habitat destruction and the relationship between network structural complexity and metacommunity robustness.The model showed that the effect of habitat destruction on biodiversity in metacommunities is not monotonically negative,due to the competitioncolonization tradeoffs between plant species which results in multi-peaked patterns in biodiversity.Species diversity in mutualistic metacommunities showed multiple peaks in response to both habitat loss and habitat fragmentation,while the effects on antagonistic metacommunities were monotonically decreasing.Both mutualistic and antagonistic metacommunities showed different responses to habitat destruction in the same bipartite network structure.Specifically,increasing network size promoted species coexistence,while increased network connectivity increased the survival of pollinators or predators,but was detrimental to the survival of plant species.Higher nestedness increased the robustness of mutualistic metacommunities to habitat destruction,while low nestedness and high modularity in bipartite networks promoted the stability of antagonistic metacommunities.Mutualistic bipartite networks are more vulnerable compared to antagonistic networks,as the species in mutualistic metacommunities are more sensitive to changes in the structure of bipartite networks,and changes in the number and frequency of interactions between plants and animals can cause large oscillations in mutualistic metacommunities.In addition,a strict hierarchical competition among multiple plant species is more likely to form competition-colonization tradeoffs than intransitive competition,resulting in stronger oscillations in biodiversity.In conclusion,by constructing a patch occupancy dynamic model of metacommunities with mutualism and antagonism,this study theoretically demonstrates a complex association between network structural properties and metacommunity robustness to habitat destruction.In particular,larger network size and higher nestedness in mutualistic bipartite networks or low nestedness and high modularity in antagonistic bipartite networks showed more robust to habitat destruction,thereby maintaining metacommunity biodiversity.Therefore,this theoretical study provides a new mechanistic explanation for multispecies coexistence from the perspective of trophic and non-trophic interactions in metacommunities,offering important implications for biological conservation.