No abstract

Despite the economic stimulus provided by many dams historically, the global experience with dam building warns that traditional approaches to water infrastructure development in a rapidly changing world carry severe risks of economic and environmental failure. First, large water projects are very capital-intensive and long-lived, costing billions of dollars to plan, build, and maintain. Yet, they are vulnerable to biased economic analyses 3 , cost overruns and construction delays, and changing environmental, economic and social conditions that can diminish projected benefits 4,5 . Under a variable and changing climate, large water infrastructure even risk becoming stranded assets 6 . Second, the principles of economic efficiency inherent in cost-benefit analysis dominate project design and performance assessment, and integrating social and environmental benefits and costs into a comprehensive economic evaluation presents significant challenges 7,8 .These costs can be substantial, as evidenced by human displacement 5,9 , local species extinctions 10 , and the loss of ecosystem services such as floodplain fisheries and other amenities 11,12 .As unanticipated economic, social and environmental costs accumulate with aging water infrastructure, society is investing in restoration projects to undo some of the long-term environmental degradation, including modifying flow releases from dams 13,14 and in some cases dam removal 15 . As the global impairment of aquatic ecosystem function becomes increasingly documented and articulated 16,17 , a broader conception of sustainable water resources management that formulates environmental health as a necessary ingredient for water security and the social wellbeing it supports is urgently needed [18][19][20] . Notably, new national directives are emerging to develop and manage river ecosystems in less environmentally harmful and more sustainable ways, including in the US 21 , Europe 22,23 , and Australia 24 . Towards a more sustainable water resources management paradigmHere we ask if a more sustainable water management philosophy can be forged to guide investment in, and design of, water infrastructure while avoiding adverse, sometimes irreversible, social and

No abstract

The Amazon is Brazil’s greatest natural resource and invaluable to the rest of the world as a buffer against climate change. The recent election of Brazil’s president brought disputes over development plans for the region back into the spotlight. Historically, the development model for the Amazon has focused on exploitation of natural resources, resulting in environmental degradation, particularly deforestation. Although considerable attention has focused on the long-term global cost of “losing the Amazon,” too little attention has focused on the emergence and reemergence of vector-borne diseases that directly impact the local population, with spillover effects to other neighboring areas. We discuss the impact of Amazon development models on human health, with a focus on vector-borne disease risk. We outline policy actions that could mitigate these negative impacts while creating opportunities for environmentally sensitive economic activities.

Land-use change is the main force behind ecological and social change in many countries around the globe; it is primarily driven by resource needs and external economic incentives. Concomitantly, transformations of the land are the main drivers for the emergence and re-emergence of malaria. An understanding of malaria population dynamics in transforming landscapes is lacking, despite its relevance for developmental and public health policies. We develop a mathematical model that couples malaria epidemiology with the socio-economic and demographic processes that occur in a landscape undergoing land-use change. This allows us to identify different types of malaria dynamics that can arise in early stages of this transformation. In particular, we show that an increase in transmission followed by either a decline, or a further enhancement, of risk is a common outcome. This increase results from the asymmetry between the relatively fast ecological changes in transformed landscapes, and the slower pace of investment in malaria protection. These results underscore the importance of reducing ecological risk, while providing services and economic opportunities to early migrants for longer periods. Consideration of these socio-ecological processes and, more importantly, the temporal scale on which they act, is critical to avoid potential bifurcations that lead to long-lasting endemic malaria.