Dryland salinity and vector-borne disease emergence in southwestern Australia

Abstract

Broad-scale clearing of native vegetation for agriculture in southwestern Australia has resulted in severe ecosystem degradation, which has been compounded by the subsequent development of large areas of dryland salinity; decreased transevaporation allows the water table to rise, dissolving ancient aeolian salt deposits and creating saline surface pools. The mosquito-borne disease Ross River virus has been noted as a potential adverse human health outcome in salinity-affected regions because the principal vector, Aedes camptorhynchus, is salt tolerant and thrives preferentially in such systems. To understand the geology and ecology underlying the relationship between land clearing and disease emergence, we examine the relationship between dryland salinity processes that determine the dissolved solids profile of saline pools in affected areas, the mosquito vectors and interactions with the human population within the disease cycle. Aedes camptorhynchus is able to survive in a wide range of salinities in pools created by dryland salinity processes. The link with disease emergence is achieved where population distribution and activity overlaps with the convergence of environmental and ecological conditions that enhance disease transmission.

Salinity impacts on river ecosystem processes: a critical mini-review

“…Ecosystem services represent the benefits humans/society receive from ecosystems and their processes and functions; therefore, a link between ecosystem processes and the human sphere must be established and must be demonstrated [87,88] and, ideally, it should be quantified how and to what extent the well-being of humans is influenced by rstb.royalsocietypublishing.org Phil. Trans.…”

Rehabilitation of degraded dryland ecosystems – review

“…Some of the relevant issues presented in the literature which could be used in a cost-benefit analysis include: the economic case for government intervention and the overall cost of dryland degradation (Kirby and Blyth 1987;Beresford 2001;Roberts and Pannell 2009;Graham et al 2010), spatial modelling and identification of dryland areas affected by salinization (Graham 1992;Ive et al 1992;Horwood 1994;Kirkby 1996;Furby et al 2010), farmers and community perceptions about the salinization problem and the proposed alternatives (Greiner 1997;Hartley et al 1998;Kington et al 2003;Khan et al 2008;Kingwell et al 2008); landscape or river basin management options (Greiner 1998;Callow 2011Callow , 2012, modelling of on-farm management alternatives and economic trade-offs (John et al 2005;Cheng et al 2009;Finlayson et al 2010;Graham et al 2010), reintroduction of native trees and shrubs (Schofield 1992;Dorrough and Moxham 2005;Thrall et al 2005), and the effects of dryland degradation on human health (Jardine et al 2007(Jardine et al , 2008a(Jardine et al , 2008b(Jardine et al , 2011Speldewinde et al 2009Speldewinde et al , 2011.…”

Climate Change, Ross River Virus and Biodiversity

“…The ecological context of RRV transmission has been considered (Weinstein, 1997;Jardine et al, 2011), and the disease has been used to illustrate the importance of responding to the research challenges presented by the Millennium Ecosystem Assessment (MEA) (Weinstein, 2005). The MEA highlighted the significant loss in biodiversity that has resulted from 'planetary overload' and, importantly, ties adverse human health outcomes to that loss.…”