Climate change, plant migration, and range collapse in a global biodiversity hotspot: theBanksia(Proteaceae) of Western Australia

Abstract

Climate change has already altered global patterns of biodiversity by modifying the geographic distributions of species. Forecasts based on bioclimatic envelop modeling of distributions of species suggests greater impacts can be expected in the future, but such projections are contingent on assumptions regarding future climate and migration rates of species. Here, we present a first assessment of the potential impact of climate change on a global biodiversity hotspot in southwestern Western Australia. Across three representative scenarios of future climate change, we simulated migration of 100 Banksia (Proteaceae) species at a rate of 5 km decade−1 and compared projected impacts with those under the commonly applied, but acknowledged as inadequate, assumptions of ‘full‐’ and ‘no‐migration.’ Across all climate × migration scenarios, 66% of species were projected to decline, whereas only 6% were projected to expand or remain stable. Between 5% and 25% of species were projected to suffer range losses of 100% by 2080, depending mainly on climate scenario. Species losses were driven primarily by changes in current precipitation regimes, with the greatest losses of species projected to occur in a transition zone between wet coastal areas and interior arid regions and which is projected to become more arid in the future. Because the ranges of most species tended to collapse in all climate scenarios, we found that climate change impacts to flora of southwestern Western Australia may be large, even under optimistic assumptions regarding migration abilities. Taken together, our results suggest that the future of biodiversity in southwestern Western Australia may lie largely in the degree to which this hotspot experiences increased drought and in the ability of species to tolerate such decreases in precipitation. More broadly, our study is among a growing number of theoretical studies suggesting the impacts of future climate change on global biodiversity may be considerable.

Controlled comparison of species- and community-level models across novel climates and communities

“…When modelling entities or attributes above the species level using SDMs, a 'predict first, assemble later' approach [2] is typically employed, wherein individual models are fitted and projected for each species, the mapped predictions of which are then aggregated or 'stacked' to infer potential changes in community-level patterns such as species richness (e.g. [3]). An alternative, but relatively rarely used, approach involves combining data from multiple species to simultaneously analyse and map patterns of biodiversity at the community level.…”

Habitat Modeling for Amaranthus pumilus: An Application of Light Detection and Ranging (LIDAR) Data

“…This modeling effort was somewhat unusual because it was targeted at a relatively small area -many such modeling efforts are done at continental or subcontinental scales (e.g., Richardson et al 2005;Fitzpatrick et al 2008;and Kivinen et al 2008) and focus on climatic variables as direct or indirect ) drivers of species' distributions. Large-scale environmental coverage data are widely available (Beaumont et al 2005), but availability of finer-scale data is variable among regions.…”

The vulnerability of native rangeland plant species to global climate change in the West Asia and North African regions

“…These assessments can be used to identify which species are likely to be significantly impacted by projected climate changes, and to assist in understanding why they may be vulnerable. A number of vulnerability assessment tools have recently been developed to assist land managers in evaluating and prioritizing actions taken in response to climate change, including mitigation strategies such as assisted migration (Fitzpatrick et al 2008). In order to enhance the adaptation of rangeland species to ongoing climate change by increasing their resilience, an assessment of their vulnerability to this risk is needed first.…”

“…Climate change is increasingly recognized as one of the greatest challenges to humankind and all other life on Earth (Fitzpatrick et al 2008). The scenarios developed by the Intergovernmental Panel on Climate Change (IPCC) project a further increase in global mean surface temperature of 2-6°C above pre-industrial levels by 2100, increased incidence of floods and droughts, and spatial and temporal changes in precipitation patterns (IPCC 2007).…”