Assessment of the Risk of Amazon Dieback

Advances in the study of giant otter (Pteronura brasiliensis): ecology, behavior, and conservation: a review

“…Deforestation and climate change: The giant otter's distributional range includes and almost coincides with the Amazon Basin and Guiana Shield, which is not only the largest repository of global biodiversity but also a key component of the global carbon cycle, which is itself a determining factor for global climate (Malhi et al, 2008;Vergara and Scholz, 2011). It is well known that changes in land-cover can be a driver of climate change through a number of feedback loops (Cox et al, 2004;Malhi et al, 2008;Nepstad et al, 2008).…”

“…It is well known that changes in land-cover can be a driver of climate change through a number of feedback loops (Cox et al, 2004;Malhi et al, 2008;Nepstad et al, 2008). On the other hand, current climate trends may unbalance the Amazon ecosystem and, in association with land use changes, may be shifting the region from a carbon sink to a carbon source (Vergara and Scholz, 2011). In principle, deforestation and global warming acting synergistically could lead to drastic biome changes hence representing a severe threat, potentially leading to a rapid decline of the giant otter populations caused by habitat degradation and habitat loss.…”

“…Various global and regional climate-modeling approaches, combining climate change impacts, deforestation and fire effects, have predicted a large-scale substitution of Amazon forest by savannah-like vegetation, a phenomenon known as dieback (Cox et al, 2004;Malhi et al, 2008;Nepstad et al, 2008;Vergara and Scholz, 2011). These studies have shown that forest fires, drought and logging engender further burning while deforestation and smoke can inhibit rainfall, exacerbating fire risk.…”

“…As deforestation and global warming proceed a 'tipping point' will be reached, whereby warmer temperatures and water stress will cause a large-scale dieback of the Amazon forest. Although there is no consensus on the prediction of the magnitude or spatial distribution of deforestation required to lead to a significant region-wide decrease in precipitation (Davidson et al, 2012), researchers agree that continued human destruction of the forest can push the climatic balance in the region in a direction that makes the dieback situation more likely (Vergara and Scholz, 2011). If sea surface temperature anomalies (such as El Niño episodes) and associated Amazon droughts of the last decade (2005 and 2010 were two 'once-in-a-century' catastrophic droughts just five years apart) continue, substantial impacts are expected by 2025-2030 and the situation will worsen by 2050 (Nepstad et al, 2008;Vergara and Scholz, 2011).…”