Research: Biodiversity and climate in tropical forests

Research summary

Manchester Met conducts research across the tropics that explores how land use and climate change affect biodiversity and ecosystem services. Our work also considers the tricky trade-offs between environmental conservation and economic development.  

Dr Alexander Lees is on the steering committee of the Sustainable Amazon Network (RAS), a multinational collective of 30 institutions involved in Amazonian ecological research. He collected data for the largest assessment of bird species responses to habitat alteration in Amazonia.

The study found that changes in forest structure and land-use disrupt seed dispersal and insect predation by forest birds in ways that mean the forest may never recover, even with effective protection in place. Dr Lees and collaborators also found that managing forests primary for their capacity to store carbon may not protect biodiversity, leading to the team to recommend that large-scale reforestation plans needed to meet joint biodiversity and carbon storage goals.  

These findings were supported by a pan-tropical study led by Dr Martin Sullivan who found that tree biodiversity and carbon stocks were decoupled in intact primary forests. 

Dr Sullivan works equitably with African and Amazonian forest research networks to assess how tropical forests respond to changes in the climate. His research has discovered a worrying situation: although tropical forests currently absorb more carbon than they emit (acting as a carbon sink), the strength of this sink is weakening, especially in South America. 

African tropical forests appear to be more resilient as carbon sinks due to their cooler climate and the long lifespans of their trees.  

Research impact 

The research of Dr Lees and the SAN directly influenced commitments by the State of Pará, Brazil to increase secondary reforest cover to 5,650,000ha by 2030 to help reach net zero climate targets. This area is almost half of the target for all of Brazil under its Nationally Determined Contributions from the Paris agreement of the UNFCCC. An official state decree enshrines the commitment in state law, which uses the research to calculate rates of forest carbon accumulation.  

Dr Sullivan’s work has been incorporated into the 2019 refinement of the IPCC’s biomass defaults, providing more up to date information about variation in carbon stocks and carbon uptake for use in carbon accounting. Research by the AfriTRON network has helped quantify the value and climate resilience of tropical forests in the Congo Basin; this evidence base allowed Gabon to secure $17m funding for forest protection from Norway. The payment is the first instalment in an agreement to provide $150m for reducing emissions from deforestation and land degradation over ten years.