Amazonian study in Science identifies conservation more cost-effective than restoration

As the 2026 El Niño intensifies across the Amazon, new research funded by the Global Centre on Biodiversity for Climate (GCBC) highlights the urgent need to protect the region’s remaining forests from disturbance.

Many conservation strategies focus on avoiding deforestation or restoring cleared land. But a new study published in Science on 17 September 2026 shows that protecting existing forests from disturbances, including selective logging and wildfires, can often provide the biggest “bang for your buck”.

An international team of researchers from the UK, Brazil, Sweden and Australia, led by scientists at Lancaster University, carried out the work. It’s the first systematic comparison of its kind, contrasting different ways to protect existing forests or restore them on agricultural land.

The analysis covered more than three million hectares in the regions of Santarém and Paragominas, in the Brazilian state of Pará, between 2010 and 2020. It combined high-resolution satellite imagery with field data from 381 survey transects across 38 catchments and 499 rural properties, as well as models mapping 160 bird species and 426 tree species.  

Using observed land-use changes, the researchers used counterfactual scenarios to assess how each strategy would have affected biodiversity and carbon stocks compared with the changes that actually occurred. The team also estimated the costs associated with each intervention, allowing the benefits delivered for the resources invested to be compared within a common framework.  

“These findings highlight the need to put in place policies and resources to prevent and tackle the wildfires that disturb and degrade tropical forests,” said Professor Jos Barlow, of Lancaster University and senior author of the study. 

“This is all the more urgent in this El Niño year. These events, combined with climate change, result in longer, hotter and more intense dry seasons across the Amazon’s ‘arc of deforestation’, greatly increasing the extent and severity of forest fires.”  

Protecting forests from disturbance pays off

Avoiding forest disturbances delivered particularly significant results. It generated the greatest benefits for forest biodiversity and was almost as important as preventing deforestation for protecting carbon stocks. 

“While no one strategy is a silver bullet, our results provide clear evidence that we should begin by prioritising the forests we have left,” said Dr Leonardo Miranda, of Lancaster University and lead author of the study. “And protection must go beyond avoiding deforestation. Avoiding forest disturbances from wildfires or logging delivered the greatest benefits for forest biodiversity.”

Restoration delivered important benefits, particularly in properties where most of the original forest had already been lost. Across the study area as a whole, however, restoration on agricultural land was less effective when implemented on its own and was also the most expensive strategy. The results show that conservation resources should be directed according to local landscape conditions. 

Combining interventions

No single intervention was sufficient to reverse biodiversity and carbon losses across the entire study area. 

“Net-gains in biodiversity and carbon storage were only achieved when both avoidance interventions were implemented. However, combining all three interventions delivered even greater gains,” said Dr Miranda. “Combined interventions will be even more important as climate change progresses, especially as forest restoration can be particularly vulnerable to wildfires.” 

The findings are particularly timely given the growing emphasis on forest restoration in global commitments and Brazilian federal and state policies. 

“Restoration is essential where forests have been lost across large areas. But our study shows that investing in new forests makes little sense if, at the same time, we fail to protect existing forests,” said the co-author Dr. Joice Ferreira, senior researcher at Embrapa and the principal investigator of the ‘Capoeira’ research programme on restoration. “Otherwise, we are pouring money into a leaky pot – restoring forests in one place while others are being degraded and lost. What we urgently need to do is integrate these policy agendas, ensuring that forest restoration goes hand in hand with protection of the forests we still have.” 

The researchers focused on two Amazonian regions, but they say the findings likely apply to tropical deforestation frontiers around the world and matter for policy beyond the tropics.

“There is a need for the companies and markets that benefit from nationally and globally traded commodities like soy and beef to take responsibility not only for deforestation, but also the degradation of remaining forests that is inextricably linked to these production systems,” said Dr. Toby Gardner, co-author and Senior Research Fellow at Stockholm Environment Institute and co-founder of the supply chain sustainability initiative Trase. 

About the research

The paper, Protecting tropical forests is more cost-effective for biodiversity and climate than restoration, was published in Science on 17 September 2026. The Sustainable Amazon Network (Rede Amazônia Sustentável) convened the research. Funders include GCBC and Brazil’s National Council for Scientific and Technological Development (CNPq).

More on the project: Enabling Large-scale and Climate-resilient Forest Restoration in the Eastern Amazon – GCBC

Photo Credits

1. Forest fire burning within primary forest in the Tapajós National Forest, illustrating within-forest disturbance caused by fire. Photo credit: Marizilda Cruppe.

2. Pygmy Antwren (Myrmotherula brachyura) recorded in the Santarém region where it occurs in the midstory and subcanopy of primary tropical rainforest. This species was used to model biodiversity value. Photo credit: Alexander Lees/Manchester Metropolitan University.

3. Drone view of a landscape in the Tapajós National Forest, showing a mosaic of undisturbed primary forest, disturbed forest [standing dead trees], secondary forest, deforested land and forest edges. This landscape illustrates the counterfactual scenarios evaluated in the study, where observed land-use transitions were modified to represent different conservation interventions. Photo credit: Marizilda Cruppe.

4. A lone tree remains standing as the surrounding forest is cleared following deforestation in the Tapajós National Forest, a protected area in the Brazilian Amazon. This image represents the deforestation scenario evaluated in the study. Photo credit: Marizilda Cruppe.

5. A skidder extracts a logged tree from the Jari region, in northern Pará, illustrating within-forest disturbance caused by selective logging. Photo credit: Jos Barlow.

6. Drone view of a landscape in the Tapajós National Forest, showing a mosaic of undisturbed primary forest, disturbed forest [standing dead trees], secondary forest, deforested land and forest edges. This landscape illustrates the counterfactual scenarios evaluated in the study, where observed land-use transitions were modified to represent different conservation interventions. Photo credit: Marizilda Cruppe.

7. A skidder extracts a logged tree from the Jari region, in northern Pará, illustrating within-forest disturbance caused by selective logging. Photo credit: Jos Barlow.