The Effect Of Warming And Nitrogen Addition On The Local Community Phylogenetic Structure Of An Alpine Meadow

Ecophylogenetics can be viewed as an emerging fusion of ecology, biogeography and macroevolution. This new and fast-growing field is promoting the incorporation of evolution and historical contingencies into the ecological research agenda through the widespread use of phylogenetic data. Including phylogeny into ecological thinking represents an opportunity for biologists from different fields to collaborate and has provided promising avenues of research in both theoretical and empirical ecology, towards a better understanding of the assembly of communities, the functioning of ecosystems and their responses to environmental changes. The time is ripe to assess critically the extent to which the integration of phylogeny into these different fields of ecology has delivered on its promise. In the context of increasing global warming and nitrogen deposition, it’s necessary that using phylogeny as a proxy for ecological similarity to understand the response of different ecosystems, and this new approach may provide theoretical basis and implications for management of biodiversity conservation. We conduct a warming and nitrogen addition experiment for three years to study the response of the phylogenetic community structure of alpine meadows to warming and nitrogen deposition. The results show that:i) functional traits show weak phylogenetic signal, phylogenetic history should be taken into account when using functional traits to explore community assembly, while this weak phylogenetic signal also indicates that both environmental filtering and competitive exclusion may be involved in the community assembly. ii) The phylogenetic community structure of the alpine meadow is dynamic at the time scale we investigated. iii) Warming and nitrogen addition changed the relative fitness of the species and improved the competition among some genetically similar species, but also exacerbated the interspecific competition between these species and resulted competition exclusion, thus the genetically dissimilar species can coexist in face of the environment change. iv) Competition between genetically close related species is more intense, as a evidence that phylogenetic relationships partially represent ecological similarity.