The phylogenetics of succession can guide restoration: An example from abandoned mine sites in the subarctic

Abstract

Phylogenetic tools have increasingly been used in community ecology to describe the evolutionary relationships among co-occurring species. In studies of succession, such tools may allow us to identify the evolutionary lineages most suited for particular stages of succession and habitat rehabilitation. However, to date, these two applications have been largely separate. Here, we suggest that information on phylogenetic community structure might help to inform community restoration strategies following major disturbance. Our study examined phylogenetic patterns of succession based on a chronosequence of three abandoned subarctic mine spoil heaps (waste piles) dating from the early 1970s, mid-1970s and early 1980s. The vegetation at each mine site was compared to the surrounding vegetation, and community structure on mines was explored assuming species pools at nested spatial scales. We found that the adjacent vegetation was more phylogenetically clustered than the vegetation on the mines, with mines demonstrating weaker phylogenetic community structure. Using simulation models, we showed that phylogenetic dissimilarity between mine sites did not depart from null expectations. However, we found evidence for species sorting along abiotic gradients (slope and aspect) on the mine sites that had been abandoned for the longest. Synthesis and applications. Understanding the trajectory of succession is critical for restoration efforts. Our results suggest that early colonizers represent a phylogenetically random subset of species from the local species pool. Over time, there appears to be selection for particular lineages that come to be filtered across space and environment. The species most appropriate for mine site restoration might, therefore, depend on the successional stage of the community and the local species composition. For example, in later succession, it could be more beneficial to facilitate establishment of more distant relatives. Our findings can improve management practices by providing relatedness information for known successful colonizers and by informing seeding decisions with knowledge of the surrounding and regional species pools. The application of phylogenetics to restoration ecology and succession is relatively new, but it has the potential to provide novel insight into the dynamics of changing community structures during succession. Understanding the trajectory of succession is critical for restoration efforts. Our results suggest that early colonizers represent a phylogenetically random subset of species from the local species pool. Over time, there appears to be selection for particular lineages that come to be filtered across space and environment. The species most appropriate for mine site restoration might, therefore, depend on the successional stage of the community and the local species composition. For example, in later succession, it could be more beneficial to facilitate establishment of more distant relatives. Our findings can improve management practices by providing relatedness information for known successful colonizers and by informing seeding decisions with knowledge of the surrounding and regional species pools. The application of phylogenetics to restoration ecology and succession is relatively new, but it has the potential to provide novel insight into the dynamics of changing community structures during succession.