Diversity patterns of seasonal wetland plant communities mainly driven by rare terrestrial species

David Deane, Damien Fordham, Fangliang He, Corey Bradshaw

    Research output: Contribution to journalArticle

    7 Citations (Scopus)

    Abstract

    In cleared landscapes, wetlands can represent important reservoirs of native plant diversity, which include terrestrial species. Depending on study aims, non-wetland plants might be removed before analysis, affecting conclusions around biodiversity and community structure. We compared the native plant communities of seasonal wetlands in a predominately agricultural landscape as defined geographically (including all species) with that of the obligate wetland assemblage. We were primarily concerned with determining how this design decision affects ecological and conservation conclusions. We analysed a survey database containing >12,900 flora records from South Australia, developing a new area-based method to remove sampling bias to include only wetlands with a near-complete census. We modelled occupancy, species-area relationships, β-diversity and nestedness under our contrasting community definitions. Terrestrial species were 57.4 % of total richness. Removing these species reduced wetland α-diversity by 45 %, but did not affect the scaling of richness with area (power-law species-area relationship z = 0.21 ± 0.01). Occupancies for wetland plants were relatively uniform, but were heavily dominated by rare (satellite) species when terrestrial plants were included, and this also increased β-diversity. Nestedness for terrestrial species occupancies was marginally lower than predicted under null models, suggesting that rare species often do not co-occur with common species. An implication of these occupancy patterns is that twice as many wetlands (and 50 % more wetland area) would be needed to include every native species within at least one wetland compared with wetland-only species.

    Original languageEnglish
    Pages (from-to)1569-1585
    Number of pages17
    JournalBiodiversity and Conservation
    Volume25
    Issue number8
    DOIs
    Publication statusPublished - 2016

    Fingerprint Dive into the research topics of 'Diversity patterns of seasonal wetland plant communities mainly driven by rare terrestrial species'. Together they form a unique fingerprint.

    Cite this