The world's first comprehensive evidence-based assessment of land degradation and restoration highlights some sobering facts regarding how worsening land degradation caused by human activities is undermining the well-being of 3.2 billion people (two fifths of the world's population), driving species extinction, intensifying climate change, and leading to increased risk of migration and conflict.
The Summary for Policymakers of the landmark Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Assessment Report on Land Degradation and Restoration, co-chaired by JRC scientist Dr Luca Montanarella*, was launched in Colombia on Monday, 26 March 2018.
The report, which aims to inform policymakers and raise awareness, details the dangers of land degradation, which cost the equivalent of about 10 % of the world’s annual gross product in 2010 through the loss of biodiversity and ecosystem services, together with a catalogue of corrective options.
The assessment, which took three years to produce, contains contributions from more than 100 leading experts from 45 countries.
Main findings of the report
Avoiding, reducing and reversing land degradation and restoring degraded land is an urgent priority to protect the biodiversity and ecosystem services that are vital to life on Earth.
Land degradation through human activities is undermining the well-being of at least 3.2 billion people, and is pushing the planet towards a sixth mass species extinction".
More than 75 % of Earth’s land areas are substantially degraded. If this trend continues, more than 90 % of the Earth’s land areas could become degraded by 2050, potentially exacerbating climate change and leading to mass migration, conflict and major food security concerns.
Wetlands are particularly degraded, with 87 % lost globally in the past 300 years.
Habitat loss and degradation are the leading causes of biodiversity loss. Between 1970 and 2012the average populations of wild land-based species fell by 38 %, and freshwater species by 81 %.
Land degradation is a major contributor to climate change. Deforestation contributes about 10 % of all human-induced greenhouse gas emissions, and loss of carbon previously stored in the soil has released up to 4.4 billion tonnes of CO2 into the atmosphere between 2000 and 2009.
According to Dr Montanarella, land degradation and climate change could reduce crop yields by an average of 10 % globally (up to 50 % in some regions) by 2050. "Most land degradation will occur in Central and South America, sub-Saharan Africa and Asia – the areas with the most land still remaining that is suitable for agriculture".
Drivers of land degradation
Rapid expansion and unsustainable management of croplands and grazing lands is the main driver of land degradation, causing significant loss of biodiversity and ecosystem services, including food security, water purification, the provision of energy, and other contributions of nature essential to people. This has reached critical levels in many parts of the world.
These drivers are mainly due to the high-consumption lifestyles of the most developed economies, and the rising consumption in developing and emerging economies. This, combined with population growth, is driving unsustainable levels of agricultural expansion, natural resource and mineral extraction, and urbanisation, which typically lead to great levels of land degradation.
What can be done
The report recommends avoiding further agricultural expansion into native habitats by increasing yields on existing farmlands, shifting towards plant-based diets and consuming less animal protein from unsustainable sources, and reducing food loss and waste.
If soils are protected and reclaimed from land degradation, they could provide more than a third of the most cost-effective greenhouse gas mitigation activities needed by 2030 to keep global warming under the 2˚C threshold, and improve food and water security, thereby helping to avoid conflict and migration.
Some examples of how avoid or reverse land degradation include reducing soil loss and improving soil health, using salt-tolerant crops, conservation agriculture and integrated crop, livestock and forestry systems, developing local livestock management practices, controlling pollution sources and better managing wetlands, and developing 'green infrastructure', wastewater treatment and river channel restoration in urban areas.
It pays to improve the environment!
The report finds that the costs involved in land restoration are far exceeded by the benefits (e.g. through higher employment). On average, the benefits of restoration are 10 times higher than the costs. In regions such as Asia and Africa, the cost of inaction is a least three times higher than the cost of inaction.
"Fully deploying the toolbox of proven ways to stop and reverse land degradation is not only vital to ensure food security, reduce climate change and protect biodiversity," says Dr Montanarella, "It's also economically prudent and increasingly urgent."
It is hoped that the evidence provided by the assessment, backed by the world's leading experts, will help policymakers make better choices for more effective action. The authors also call for greater commitment and more effective cooperation at the national and local levels to achieve the goals of zero net land degradation, no loss of biodiversity and improved human well-being.
*Luca Montanarella from the JRC’s Land Resources Unit co-chaired the Assessment, together with Prof. Robert Scholes of South Africa, in his capacity as the Chair of the Global Soil Partnership’s Intergovernmental Technical Panel on Soils (ITPS).
- Summary for policymakers of the thematic assessment of land degradation and restoration
- IPBES Media Release: Worsening Worldwide Land Degradation Now ‘Critical’, Undermining Well-Being of 3.2 Billion People
- Global Soil Partnership’s Intergovernmental Technical Panel on Soils
- Data publicării
- 28 martie 2018