Amazon forests failing to keep up with climate change

November 08, 2018

A team of more than 100 scientists has assessed the impact of global warming on thousands of tree species across the Amazon to discover the winners and losers from 30 years of climate change. Their analysis found the effects of climate change are altering the rainforest's composition of tree species but not quickly enough to keep up with the changing environment.

The team, led by University of Leeds in collaboration with more than 30 institutions around the world, used long-term records from more than a hundred plots as part of the Amazon Forest Inventory Network (RAINFOR) to track the lives of individual trees across the Amazon region. Their results found that since the 1980s, the effects of global environmental change - stronger droughts, increased temperatures and higher levels of carbon dioxide in the atmosphere - has slowly impacted specific tree species' growth and mortality.

In particular, the study found the most moisture-loving tree species are dying more frequently than other species and those suited to drier climates were unable to replace them.

Lead author Dr Adriane Esquivel Muelbert, from the School of Geography at Leeds, said: "The ecosystem's response is lagging behind the rate of climate change. The data showed us that the droughts that hit the Amazon basin in the last decades had serious consequences for the make-up of the forest, with higher mortality in tree species most vulnerable to droughts and not enough compensatory growth in species better equipped to survive drier conditions."

The team also found that bigger trees - predominantly canopy species in the upper levels of the forests - are outcompeting smaller plants. The team's observations confirms the belief that canopy species would be climate change "winners" as they benefit from increased carbon dioxide, which can allow them to grow more quickly. This further suggests that higher carbon dioxide concentrations also have a direct impact on rainforest composition and forest dynamics - the way forests grow, die and change.

In addition, the study shows that pioneer trees - trees that quickly spring up and grow in gaps left behind when trees die - are benefiting from the acceleration of forest dynamics.

Study co-author Oliver Phillips, Professor of Tropical Ecology at Leeds and founder of the RAINFOR network said: "The increase in some pioneer trees, such as the extremely fast growing Cecropia, is consistent with the observed changes in forest dynamics, which may also ultimately be driven by increased carbon dioxide levels."

Co-author Dr Kyle Dexter, from the University of Edinburgh, said: "The impact of climate change on forest communities has important consequences for rain forest biodiversity. The species most vulnerable to droughts are doubly at risk, as they are typically the ones restricted to fewer locations in the heart of the Amazon, which make them more likely to be extinct if this process continues.

"Our findings highlight the need for strict measures to protect existing intact rainforests. Deforestation for agriculture and livestock is known to intensify the droughts in this region, which is exacerbating the effects already being caused by global climate change."
-end-
Further information:

Images available for download: https://drive.google.com/open?id=1wSZrOfPyWdINxdswdNqFinbW44AMWloj

The paper Compositional response of Amazon forests to climate change is published in Global Change Biology 8 November 2018 (DOI: 10.1111/gcb.14413)

RAINFOR website: http://www.rainfor.org/

For more information or to arrange interviews, contact press officer Anna Harrison at the University of Leeds a.harrison@leeds.ac.uk or +44(0)113 343 4031.

University of Leeds

The University of Leeds is one of the largest higher education institutions in the UK, with more than 33,000 students from more than 150 different countries, and a member of the Russell Group of research-intensive universities.

We are a top ten university for research and impact power in the UK, according to the 2014 Research Excellence Framework, and are in the top 100 of the QS World University Rankings 2019. Additionally, the University was awarded a Gold rating by the Government's Teaching Excellence Framework in 2017, recognising its 'consistently outstanding' teaching and learning provision. Twenty-six of our academics have been awarded National Teaching Fellowships - more than any other institution in England, Northern Ireland and Wales - reflecting the excellence of our teaching. http://www.leeds.ac.uk

University of Leeds

Related Climate Change Articles from Brightsurf:

Are climate scientists being too cautious when linking extreme weather to climate change?
Climate science has focused on avoiding false alarms when linking extreme events to climate change.

Mysterious climate change
New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past.

Mapping the path of climate change
Predicting a major transition, such as climate change, is extremely difficult, but the probabilistic framework developed by the authors is the first step in identifying the path between a shift in two environmental states.

Small change for climate change: Time to increase research funding to save the world
A new study shows that there is a huge disproportion in the level of funding for social science research into the greatest challenge in combating global warming -- how to get individuals and societies to overcome ingrained human habits to make the changes necessary to mitigate climate change.

Sub-national 'climate clubs' could offer key to combating climate change
'Climate clubs' offering membership for sub-national states, in addition to just countries, could speed up progress towards a globally harmonized climate change policy, which in turn offers a way to achieve stronger climate policies in all countries.

Review of Chinese atmospheric science research over the past 70 years: Climate and climate change
Over the past 70 years since the foundation of the People's Republic of China, Chinese scientists have made great contributions to various fields in the research of atmospheric sciences, which attracted worldwide attention.

A CERN for climate change
In a Perspective article appearing in this week's Proceedings of the National Academy of Sciences, Tim Palmer (Oxford University), and Bjorn Stevens (Max Planck Society), critically reflect on the present state of Earth system modelling.

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).

Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.

Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.

Read More: Climate Change News and Climate Change Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.