The dataset comprises of a biological and a spatial component. Biological data: This was collated from several sources, collected over the period 2000-2009. Data are lists of presence-absence of 215 native plant species (i.e., exotic species removed) from 76 seasonal wetlands (size range 0.5 - 35 ha) located on the Fleurieu Peninsula, South Australia (centred on latitude 35.5 °S). After data were collated into a single dataset, sampling bias was removed to create a dataset of near-complete census wetlands. Spatial data: For each of the 76 wetlands a small amount of spatial data is also provided, i.e., area, centroids, catchment etc. The dataset could be of interest for any typical community data analysis (e.g. beta diversity, similarity, assembly)- provided only native wetland plant species are of interest. Data presented here were used to model extinction risk, species-area relationships, occupancy distributions and so on.
Credit
We at TERN acknowledge the Traditional Owners and Custodians throughout Australia, New Zealand and all nations. We honour their profound connections to land, water, biodiversity and culture and pay our respects to their Elders past, present and emerging. There are two data custodians for component datasets used in this analysis. 1). South Australian Department of Environment, Water and Natural Resources; 2). The Conservation Council of South Australia
Purpose
Wetlands are among the most threatened habitats on Earth. They are essential components of functional landscapes, providing habitat for native flora and fauna as well as supporting critical ecosystem services. Loss of wetland biodiversity threatens these values. There is an urgent need to understand patterns of wetland biodiversity, the processes creating these and the risk of species loss to plan effective intervention. Species-area relationships have a successful, although controversial, history of quantifying the risk of extinction in terrestrial biomes, and can provide rapid estimates of extinction risk at a range of scales without the need for extensive datasets. Prior to this research, applications of species-area relationships in extinction risk were limited to island archipelagos and formerly continuous terrestrial habitats that had become fragmented. Naturally occurring, discrete habitat types such as wetlands have been ignored. The project addresses this gap, demonstrating that area-based methods can, be successfully applied to predict extinction risk in wetland communities. Before considering extinction risk the project analysed patterns of wetland plant diversity and occupancy and how competing community-assembly processes produce more or less unique combinations of species among wetlands. The project showed that much of the plant community diversity in seasonal wetlands in South Australia is driven by rare terrestrial species of wetland fringes, which assemble from a much larger available species pool. The distribution of these rare species was not strongly related to wetland size, suggesting that changes in the number or total area of wetlands could result in different extinction dynamics, depending on how they affected endemic species. The project therefore compared risks associated with loss of complete wetlands (patch loss), with loss of the equivalent wetland area while maintaining the total number of wetlands. Higher extinction risk was associated with the loss of complete wetlands than the equivalent area loss shared among all wetlands. Moreover, for a given area loss, small wetlands had a much higher risk of species loss due to the distribution of endemic species.
Lineage
Data Collection Summary: A range of probabilistic (area-controlled e.g., quadrats), systematic searches and simple species lists were used to collect the data in the sources collated. Data are collated from a number of different surveys, each using different methods to collect the data (described in source materials listed in the metadata).
