Environmental change: prospects for conservation and agriculture in a southwest Australia biodiversity hotspot

Abstract

ABSTRACT. Accelerating environmental change is perhaps the greatest challenge for natural resource management; successful strategies need to be effective for decades to come. Our objective is to identify opportunities that new environmental conditions may provide for conservation, restoration, and resource use in a globally recognized biodiversity hotspot in southwestern Australia. We describe a variety of changes to key taxonomic groups and system-scale characteristics as a consequence of environmental change (climate and land use), and outline strategies for conserving and restoring important ecological and agricultural characteristics. Opportunities for conservation and economic adaptation are substantial because of gradients in rainfall, temperature, and land use, extensive areas of remnant native vegetation, the ability to reduce and ameliorate areas affected by secondary salinization, and the existence of large national parks and an extensive network of nature reserves. Opportunities presented by the predicted environmental changes encompass agricultural as well as natural ecosystems. These may include expansion of aquaculture, transformation of agricultural systems to adapt to drier autumns and winters, and potential increases in spring and summer rain, carbon-offset plantings, and improving the network of conservation reserves. A central management dilemma is whether restoration/preservation efforts should have a commercial or biodiversity focus, and how they could be integrated. Although the grand challenge is conserving, protecting, restoring, and managing for a future environment, one that balances economic, social, and environmental values, the ultimate goal is to establish a regional culture that values the unique regional environment and balances the utilization of natural resources against protecting remaining natural ecosystems.

Freshwater tributaries provide refuge and recolonization opportunities for mussels following salinity reversal

“…As one of the world's most heavily salinized landscapes (Halse et al, 2003, Pettit et al, 2015, southwestern Australia is providing a growing number of examples of salinity reversal through improved catchment management (Mayer et al, 2005), however, reversing the impacts on aquatic biodiversity represents an additional challenge (Arle and Wagner, 2013, Cañedo-Argüelles et al, 2013, Herbert et al, 2015. Mussels are important ecosystem engineers and their global decline is having measurable effects on ecosystem processes (Vaughn et al, 2015, Vaughn, 2018.…”

“…Mediterranean-climate (med-) regions are heavily impacted by secondary salinity, and the issue is exacerbated by coexisting stressors, such as acidification, water abstraction, and climate change (Degens et al, 2012, Robson et al, 2013, Estévez et al, 2019. In the med-region of southwestern Australia, widespread clearing of native vegetation has caused approximately 56% of the region's large rivers to turn brackish or saline (Mayer et al, 2005, Beatty et al, 2011, and much of the regions highly endemic aquatic fauna is now restricted to remnant freshwater tributaries closer to the coast (Beatty et al, 2011, Pettit et al, 2015. In recent years, legislated control on land clearing, and revegetation of the agricultural inland area has helped to slow secondary salinization, and salinity has even began to reverse in some rivers (Mayer et al, 2005).…”

A structured analysis of risk to important wildlife elements in three Australian Wildlife Conservancy sanctuaries

“…The risk analysis has clearly identified a high belief in the vulnerability of species in many of the vegetation elements to a range of risk factors: decreasing availability of water, climate warming, over-grazing and disease. Alteration to vegetation composition and structure as a result of changes in temperature and rainfall (or climate change), in addition to the effects of disease and over-grazing, has been broadly recognised as major issue for some time now (Hughes 2003;Pettit et al 2015). Similarly, the interacting effects between climate change, vegetation composition and structure, and habitat suitability for fauna are now well established (Pettorelli et al 2005; Cell shading indicates the aggregated importance estimate (mean of the maximum; the darker red the box, the greater the believed risk factor importance), and the analysis has been subset into three equal levels or certainty (left to right, higher spread = less certainty) and two equal levels of agreement (top to bottom).…”

Using a social-ecological system approach to enhance understanding of structural interconnectivities within the beekeeping industry for sustainable decision making

“…Land clearing has likely contributed to reduced precipitation (Pitman et al 2004, Andrich andImberger 2013) and altered groundwater levels (Dawes et al 2012), which have adversely affected the biodiversity of the region (Brouwers et al 2013, Mastrantonis et al 2019. The declining trend in precipitation since 1970 is projected to continue into the future (Hughes 2011, Smith and Power 2014, Pettit et al 2015, which has implications for survival and distribution of forage resources. For example, drought can have an adverse impact on the growth and flowering of melliferous (nectar-producing) flora (Benecke 2007).…”