Amazonia facing threats of deforestation and climate change

Study shows that combined effects of climate change and deforestation may lead to halving of tree richness by 2050

Data resources used via GBIF : Occurrences of 6,394 species
Senna reticulata
Carrion crow bush (Senna reticulata) observed in Manaus, Brazil by crax. Photo via iNaturalist (CC BY-NC 4.0)

Holding close to 13 per cent of all trees of the world, the Amazonian lowlands is the largest rainforest block on Earth with a richness of up to 16,000 species. This immense tree diversity is threatened by both deforestation and climate change, and assessing the relative impacts of these threats is crucial to conservation.

In this study, researchers used environmental suitability models based on GBIF-mediated occurrences of nearly 7,000 Amazonian trees to estimate impacts of climate change. They also used historical deforestation data to predict future losses.

The authors found that by 2050, deforestation alone may cause a decline in richness of 19-36 percent, while climate change may account for 31-37 per cent. Combined, however, the effect may reach 58 per cent loss of richness—with the worst outlook in the portion of the Amazonian forest outside current protected areas, accounting for roughly half of the total.

With the major importance of the rainforest in absorbing atmospheric C02 and regulating climate, this study urges expanded protected area networks and an urgent halt to deforestation, to help mitigate climate change and avoid species collapse in Amazonia.

Original article

Gomes VHF, Vieira ICG, Salomão RP and ter Steege H (2019) Amazonian tree species threatened by deforestation and climate change. Nature Climate Change. Springer Science and Business Media LLC 9(7): 547–553. Available at: https://doi.org/10.1038/s41558-019-0500-2