Climate shift changes everything from genes to ecosystems
Climate change is having a profound effect on every aspect of life on Earth‚ from genes to entire ecosystems‚ with worrying consequences for humans.
These changes are of major concern not just for some distant future but now‚ according to new research published in the journal Science on Friday‚ co-authored by Dr Wendy Foden at Stellenbosch University.
Foden said the changes “are more extensive than we expected”.
Researchers identified a set of core ecological processes that underpin the functioning of healthy ecosystems. Of 94 processes considered‚ published in peer-reviewed literature‚ 82% showed robust evidence of impacts from climate change.
They included changes to genetic diversity or seasonal migration that influence the functioning of healthy marine‚ freshwater and terrestrial ecosystems‚ the Faculty of Science at Stellenbosch University said in a statement.
Foden is chair of the International Union for the Conservation of Nature’s (IUCN) Species Survival Commission and Climate Change Specialist Group‚ where the study originated.
Dr Brett Sheffers‚ lead author from the University of Florida‚ said there was evidence that‚ with only 1 degree Celsius of warming globally‚ major effects were already being felt: “The impacts range from individual genes changing‚ significant shifts in species’ physiology and physical features such as body size‚ and species moving to entirely new areas.”
The researchers warned that the many observed effects of climate change at different levels of biological organisation pointed to an increasingly unpredictable future for humans in terms of food security and human health. Healthy ecosystems contribute to climate mitigation and adaption by sequestering substantial amounts of carbon‚ regulating local climate and reducing risks from climate-related hazards such as floods‚ sea-level rise and cyclones‚ the report said.
Foden said many of the effects of climate change had already been observed in Africa. A 2007 study found that Southern Africa’s Quiver Trees (Aloe dichotoma) were suffering from high mortality and poor reproduction in their hot‚ arid northern distribution range in Namibia as a result of increased drought stress. But at their southern range edge in South Africa‚ where conditions were previously at the limit of their tolerance for cool‚ wet conditions‚ populations have been rapidly expanding.
Professor Guy Midgley‚ head of the global change biology research group at Stellenbosch University’s Department of Botany and Zoology‚ said the Science paper highlighted what is being seen on the ground in South Africa.
“Climate change impacts have now become widespread and are accumulating more quickly than we expected. It is essential that we act decisively and quickly to reduce our greenhouse gas emissions worldwide‚” he said.