Latitudinal patterns in phylogenetic and functional diversity of Diptera in temperate bogs

Abstract

Conservation of biodiversity is growing in interest, and wetlands are disappearing at an alarming rate, so understanding how communities are assembled and how interactions among species and ecosystems influence evolution is critical to the management of threatened habitats. We compared diversity and assemblages of peatland Diptera within and between ecoregions in Québec, Canada. We then determined the phylogenetic structure of peatland Diptera communities and how the structure differed with spatial scale (trap, site, ecoregion). Finally, we tested alpha and beta diversity along environmental and spatial gradients to determine which processes influence Diptera communities and diversity. Bogs across the three ecoregions support similar abundance, species richness, and functional diversity. We found that the major forces structuring Diptera assemblages in bogs across Québec are stochastic processes such as dispersal limitations. However, those random patterns change to clustering when anthropogenic disturbances modify the landscape. Assembly rules are mostly dictated by patch and landscape parameters specific to each ecoregion affecting dispersal and establishment between sites. Conservation of mobile organisms in habitats such as bogs will depend on conservation plans focusing on both patch quality and surrounding landscape, and that different conservation strategies need to be applied in different ecoregions.