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GEO-6 Regional Assessment for North America


awareness is high, and the level of scientific expertise is perhaps unparalleled.


There is a growing recognition that a holistic approach to environmental and human health is necessary, reflected in developments such as the One Health Approach. The number and size of protected areas is on the increase. Organic farming and urban agriculture are both expanding, opening new space for incentive-based government policies.


However, extinction is on the horizon for many species as contaminants, land-use change, invasive species, and altered climatic conditions continue to take their toll on indigenous flora and fauna. There are genuine concerns that the ecosystem services currently taken for granted, such as natural waste processing and the provision of natural remedies, could reach pressure thresholds in the future, especially if urban infrastructure is not considerably updated and improved for efficiency and effectiveness. Though there are a few promising exceptions, the need for reduced fragmentation of habitats and greater connectivity between protected areas is not being met. Adjustments to North American lifestyle and production methods are necessary, part of the bigger picture of moving towards a post-industrial economy and society.


2.4 Freshwater


2.4.1 Introduction to water issues in North America


North America contains 13.2 per cent of global renewable freshwater resources (FAO 2014). Most communities in North America are generally recognized as having safe and reliable access to water at an affordable cost, with some exceptions, including in rural areas and on certain tribal lands in the US. However, water security in the US and Canada is quite high currently, due to the infrastructure and treatment available to mitigate the effects of variable water flows and pollution (Vörösmarty et al. 2010). The relatively high quality of water in North America contributes


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to relatively good public health, and North Americans have some of the lowest rates of water-borne disease in the world. There are some areas of the region for which safe and reliable sources of drinking water are threatened, in particular rural communities dependent on shallow aquifers that are increasingly contaminated by nitrates, and many of Canada’s indigenous communities (Daley et al. 2015; CCA 2013, CCA 2014). The long-term sustainable supply of freshwater for irrigation, industry, and municipal uses is also undermined by reliance on groundwater sources that are being depleted and contaminated, and the increasing threat of drought and water scarcity in arid regions.


North America uses substantially more water per person than any other region in the world, although recent trends indicate that water withdrawals are declining even with population and economic growth.The average


North


American’s awareness of water security has been enhanced by media coverage of the drought moving through the US South and West over the last decade. Segments of the agricultural economy, particularly west of the 100th meridian, are dependent on unsustainable withdrawals of water from ancient and slow-to-recharge aquifers and increasingly depleted surface water systems. Depletion of aquifers also reduces the base flow in perennial streams, resulting in the degradation of important freshwater aquatic systems. Quantities and recharge rates of groundwater remain poorly understood, complicating an ability to ensure sustainable use and avoid contamination of this important water source. In the Southwestern US, communities are also highly dependent on reservoir storage that is vulnerable to contamination associated with watershed development and evaporation fueled by climate change.


Projections show that disparities between demand and supply will become more severe with population growth, increasing economic aspirations, and climate change. Similar economic and food security consequences extend globally.


Most of the water quality issues in North America affect aquatic life and recreational uses of surface waters (see


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