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GEO-6 Regional Assessment for North America


nutrition (Horwitz et al. 2015; Hunter 2015; Alcock 2014; Beyer 2014). Evidence suggests that restoring ecosystem services in urban areas also results in demonstrable concrete economic benefits (Elmquist 2015; Goddard et al. 2010).


Resource extraction and energy production


Resource extraction, particularly for energy production, has been a major driver of land-use change across North America, and restoration efforts are vital for both the regeneration of wild spaces and the survival of endangered species.


Forestry retains its status as a major employer in both Canada and the US. Although clearcutting is less common, there are still significant threats to biodiversity associated with large- scale forestry operations. In many cases, selective logging and legislation has protected wild species at risk, such as the spotted owl (Strix occidentalis), but at costs to the industry and logging communities.


Increased demand for biofuel in Europe has made the US the world’s largest exporter of wood pellets. The systemic removal of small sections of the boreal forests of Alberta and Manitoba for the extraction of oil sands has been perhaps the most notable land-use change in North America over the past decade, though this has slowed in recent years due to falling oil prices and the persistence of forest fires. Invasive species, such as the mountain pine beetle (Dendroctonus ponderosae), present another threat to forest ecosystems and biodiversity (see Section 2.8; Box 2.8.2). Overall, “Canada’s 348 million hectares of forest lands represent about 9 per cent of the world’s forest cover, but account for only 0.3 per cent of global deforestation” (NRCanada 2015).


Although some forms of energy generation have a


considerably greater impact than others, especially when the compounding effects of climate change are considered, all forms of centralized energy production have an effect on biodiversity, wildlife,


communities (Fthenakis and Kim 2009): oil sands production impacts boreal forests and rivers;


ecosystems and surrounding hydraulic fracking


infrastructure, including wells can disrupt local ecosystem 58


services including water provision; mountain-top coal mining harms fragile ecosystems; offshore oil and gas drilling can threaten marine life; hydropower and large-dam construction contributes to reservoir-linked displacement; wind farms can harm birds (Sovacool 2009); and solar farms can fragment habitat. The creation of power lines and the construction of new roads to sites, essential for most forms of energy production, cause land and habitat fragmentation. But, increasingly, citizens are presented with an array of personal choices regarding their energy sources, and communities are making collective decisions favouring less intrusive energy projects.


Contaminants


Apart from microplastic contamination (see Figure 2.3.2), concentrations of legacy contaminants in terrestrial, freshwater and marine systems have generally declined over the past 10–40 years, though mercury levels are increasing in some wildlife in some areas (Braune et al. 2015). Fortunately, levels of legacy contaminants – banned or restricted chemicals such as polychlorinated biphenyls (PCBs) – have declined in wildlife in the Strait of Georgia, the St Lawrence Estuary, the Great Lakes, the Bay of Fundy and the Arctic since the 1970s, although rates of decline in some areas have slowed in recent years.


The recovery of peregrine falcons (Falco peregrinus) and American bald eagles, after the banning of DDT demonstrates that some species can rebound after the contaminant stress has been lifted. Novel flame retardants and polybrominated diphenyl ethers (PBDEs) are examples of emerging contaminants which have more recently been found to spread through and accumulate in ecosystems. Levels of PBDEs have increased since the 1980s in fish, birds, whales and polar bears (Wolschke et al. 2015). Contaminants can directly affect wildlife health and reproduction and increase vulnerability to other stressors.


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