Imagine effective action on deforestation

This is the latest (9th August) edition of Imagine – a weekly synthesis of academic insight on solutions to climate change, distributed by The Conversation. This edition was written by Jack Marley, energy and environment editor and discusses why a gathering of countries in South America matters for the whole world.

A summit attended by eight Amazon nations in the northern Brazilian city of Belém has ended with an agreement to bolster regional cooperation in protecting the Amazon rainforest, but no common goal to halt deforestation by 2030. Brazilian president and host Luiz Inácio Lula da Silva vowed to reverse the "plundering" which he said typified his predecessor Jair Bolsonaro's approach to the Amazon. His government has already had some success: satellite images indicate deforestation in July 2023 was at least 60% lower than in July last year. Tropical rainforests like the Amazon are vast carbon sinks which keep global temperatures in check. Scientists are worried that deforestation and hotter and drier weather caused by climate change is pushing this naturally humid ecosystem to the brink of collapse. But "deforestation" is an imprecise term which can sometimes obscure what is actually happening to the world's largest rainforest – and who needs to act. "Just 20% of the world’s tropical forests are classified as intact," says Tommaso Jucker, a lecturer in biology at the University of Bristol. "The rest have been impacted by logging, mining, fires, or by the expansion of roads or other human activities. And all this can happen undetected by the satellites that monitor deforestation." Reported rates of deforestation do not capture the full picture. Jucker says that happening on a far bigger scale, at least in tropical forests, is degradation: once uninterrupted forest being broken into smaller, isolated parcels. Riddled with roads and perforated with mines and saw mills, rainforests dry out quicker and can flip from a sink to a source of the greenhouse gases driving climate change. A new study has confirmed that a leading cause of forest degradation in the Amazon is fire deliberately set to clear land for farming. July usually marks the start of this clearing season in Brazil, which is partly why many observers have been so impressed by the recent plunge in forest loss. A long-term solution must involve convincing farmers in the Amazon not to set fires, say Federico Cammelli, Jos Barlow, and Rachael Garrett, conservation experts at the Swiss Federal Institute of Technology Zurich, Lancaster University and the University of Cambridge respectively. "Fire is so appealing to farmers because it does the work of fertilisers, pesticides and labourers for free," they say. "First, they leave the land fallow to recover after a few harvests and it’s overtaken by pioneer plants and pests. The regrowing vegetation is then slashed and burned, providing a low-cost way to clear debris and fertilise the land while removing pests." Cammelli, Barlow and Garrett have shown that slash and burn farming degrades the soil and is less profitable in the long run than using machinery, planting trees and rotating pastures. Their research suggested farms using fire earned 63% less than those that didn't. But poverty prevents many farmers from investing in these changes. Once abundant rainfall and moist forests meant fires used to remain in areas that had been cleared before, the trio say. Climate change has increased the risk of crop fires burning out of control. In a survey they conducted with 580 farmers in the eastern Amazon, 43% said they were on the receiving end of an escaped fire between 2014 and 2019. "Just as the risk of escaped fires drives more farmers to light fires of their own, it also discourages people from investing in their own fire control measures," Cammelli, Barlow and Garrett add. The world's responsibility So, how to break this cycle? The trio say subsidising alternative farming techniques "may be the best option". At the recent summit, the leaders of the Amazon nations called on rich countries to help develop a programme of aid akin to a Marshall Plan for the rainforest – money which could help the region invest in more sustainable livelihoods. Another recent study indicates that a global effort is indeed necessary to stop the degradation of rainforests around the Earth's equator – by tempering demand for forest products, including fossil fuels. "While farming continues to drive deforestation around the world, 60% of the destruction of Earth’s large, intact forests is caused by other forces," say Siyi Kan and Bin Chen. Kan studies emission and trade analysis at UCL while Chen is an environmental engineer at Fudan University, China. "In particular, our research shows that more than one-third of this destruction can be blamed on the production of commodities for export, particularly timber, minerals and oil and gas." Brazil is reported to be eyeing a potentially huge deposit of oil at the mouth of the Amazon river. Colombian President Gustavo Petro urged Lula to block new oil developments in the region, but no agreement was reached at the summit. Although 60% of the Amazon lies within Brazil, there are unique threats to the world's largest rainforest in neighbouring countries. Victor Galaz, an associate professor at Stockholm University's Resilience Centre, describes the situation in Bolivia, where forest loss rose by a third last year: "The accelerated loss of tropical rainforest is the result of destructive and familiar combination: increased global demand for commodities such as soy and cattle, and extractive national and regional policies with the explicit ambition to boost economic growth with little consideration on its environmental impact." - Jack Marley, Environment commissioning editor To join the 20,000 people who get one email every week from the Conversation about climate change. Subscribe to Imagine.

Forests are breaking up in the tropics but coming together elsewhere – here’s what it means for wildlife and the climate Forest fragmentation is causing the deepest and darkest parts of the world’s forests to shrink. Read more In the Amazon, forest degradation is outpacing full deforestation Forest that has been disturbed – but not cleared – by logging or fire can be hard to spot from satellites. Read more Amazon fires trap farmers into poverty – and into setting more fires Fires that burn the forest burn crops and pastures alike. But farmers in the eastern Amazon are left with few good options. Read more Global supply chains are devouring what’s left of Earth’s unspoilt forests More than 60% of global intact forest loss is unrelated to farming, our research shows Read more The forgotten Amazon: as a critical summit nears, politicians must get serious about deforestation in Bolivia Surging deforestation in Bolivia means the country now ranks as one of the highest carbon emitters in the world. Read more One of 2023’s most extreme heatwaves is happening in the middle of winter Parts of Argentina and the Chilean Andes experienced some of their highest temperatures on record. Read more Latest from The Conversation on climate change

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