SCIENTISTS based in the UK and China have concluded that forest clearance for rubber production is happening up to three times faster than previously thought.
Two groundbreaking studies, published in the journals Nature and Conservation Letters, demonstrate that the impact of the global rubber trade on forests has been serially and substantially underestimated.
Using the latest satellite technology and cloud computing, and a review of more than 100 case studies, the fresh evidence reveals that rubber-driven forest loss is significantly larger than previously reported estimates, which have been widely used to inform policy.
Led by the Royal Botanic Garden Edinburgh (RBGE), in collaboration with Kunming Institute of Botany (KIB), Chinese Academy of Sciences and CIFOR-ICRAF China Country Program, the satellite imagery-based paper in Nature shows that rubber-related deforestation could be three times greater than previously believed. Over 4m hectares (and area the size of Switzerland) have been lost to rubber plantations in the last 30 years, including more than 1 million hectares of plantations created in key biodiversity areas.
Dr Yunxia Wang, first author of the study, explained, “Rubber was already known to lead to forest loss, but quantifying the damage has been challenging. Because it is difficult to distinguish from natural forest on satellite imagery, it has received reduced attention when looking at the losses caused by commercial plantations. However, thanks to expanding earth observation and computing technology, there are increasing opportunities to map ‘difficult’ commodities. The results have been sobering.”
Underscoring the significance of this pioneering research, Professor Peter Hollingsworth, Deputy Keeper and Director of Science at RBGE said, “The study highlights the importance of rigorous quantifications of the effects of cash crops on the environment. This is now increasingly possible thanks to advancements in earth observation technology.”
Senior author Dr Antje Ahrends said, “While deforestation linked to rubber is widespread, some countries are of particular concern. In Cambodia, for example, over 40% of rubber plantations are associated with deforestation. Our maps show that rubber plantations have encroached into areas of global importance for the protection of biodiversity, with over one million hectares planted in these areas. With 70% of the world’s natural rubber yields destined for tyre manufacture, demand is not likely to diminish and the threat this poses to biodiversity should not be underestimated. In addition, while predominantly grown by smallholders with the potential to support livelihoods, rubber is also associated with land grabbing and human rights infringement in some countries.”
A separate systematic review of case studies and analysis of recent trends in rubber area and yield, published in Conservation Letters and led by Bangor University, also indicated that rubber is regularly linked to deforestation.
Warning that, as demand grows and yields stagnate, continued deforestation for rubber is to be expected, lead author Dr Eleanor Warren-Thomas said, “Our analysis shows substantial expansion of rubber plantations has occurred in many producer countries since 2010, with particularly rapid increases in new locations such as Cote d’Ivoire. Some 2.7 million to 5.3 million hectares of additional harvested area could be needed to meet industry estimates of demand by 2030. It is critical that existing rubber producers are supported to improve their yields and maintain production, to avoid ongoing expansion of plantation area.”
Both studies emphasise that while it is critical to halt deforestation associated with rubber, it is vital that smallholders, who account for 85% of natural rubber production, are not marginalised by regulations.
Dr Maria Wang, from the Grantham Centre for Sustainable Futures at the University of Sheffield and co-author of the study published in Conservation Letters, said, “Rubber smallholders and industry understandably fear extra burdens placed on them by regulations. However, these studies show that the biodiversity impacts and deforestation from rubber cannot be ignored and that there is a need for solutions that work for smallholders, without putting any more pressure on the planet.”
Dr Ahrends concluded, “While it is encouraging to see an increasing number of initiatives and policy changes that aim to halt commodity-driven forest loss, there is a risk of inflexible regulation marginalising the poor as only wealthy rubber producers and traders can afford to pay remote-sensing companies to verify that goods are deforestation-free.
“We are, therefore, working with smallholder initiatives and other key players in the sector, including the Forest Stewardship Council, ZSL, and the Global Platform for Sustainable Natural Rubber, to ensure that our rubber and deforestation maps are widely and easily accessible to all stakeholders, in particular to smaller economic players.”
Professor Jianchu Xu, Head of Centre for Mountain Futures at KIB and Principal Scientist from CIFOR-ICRAF China Program said: “As one of the largest rubber consumers, China is very concerned about displaced deforestation from international trade. With support from the China-UK Collaboration on International Forest Investment and Trade Program, we have developed the world’s Guidance for Sustainable Natural Rubber to support the implementation of the Kunming-Montreal Global Biodiversity Framework.”