Читать книгу Ecology - Michael Begon - Страница 52

Khaliq et al. (2014) found that most of the endotherm species in their dataset (Figure 2.20b, c) currently experience maximum ambient temperatures that are within their tolerance limits during most months of the year, and note that in a warming climate many should still be able to find suitable temperature conditions within their current range. However, vulnerability to higher future ambient temperatures increases from the poles towards tropical regions, even though increases of temperature predicted for temperate and polar regions exceed those in the tropics. This is because species in tropical regions tend to live closer to their upper temperature limits and even small increases in ambient temperatures may challenge their survival. Moreover, projections of declining precipitation in tropical areas worsen the prospects for tropical species, because water availability is crucial for endotherms to compensate thermal stress. These results highlight the threats from global climate change in tropical zones, which harbour the greatest amount of biodiversity worldwide.