Land degradation caused by human activities undermines the well-being of at least 3.2 billion people, costs more than 10% of annual global GDP in lost ecosystem services and endangers food security, warn a hundred experts from 45 countries in a three-year assessment report published yesterday (26 March).
“By 2050, the combination of land degradation and climate change is predicted to reduce global crop yields by an average of 10%, and by up to 50% in some regions. In the future, most degradation will occur in Central and South America, sub-Saharan Africa and Asia – the areas with the most land still remaining that are suitable for agriculture,” the report reads.
Produced by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) under the auspices of the United Nations, the organisation describes the report as “the world’s first comprehensive evidence-based assessment of land degradation and restoration”.
The experts explain that ongoing land degradation worldwide is caused by high consumption lifestyles in more developed economies, combined with rising consumption in developing and emerging economies.
To meet the needs for this “high consumption lifestyle”, crop and grazing lands are being expanded into native vegetation, leading to unsustainable agricultural and forestry practices and, in specific areas, an increase in urban expansion, infrastructure development and extractive industry, they explain.
Unless urgent and concerted action is taken, “land degradation will worsen in the face of population growth, unprecedented consumption, an increasingly globalised economy and climate change”, the experts warn.
The report also finds that land degradation is a major contributor to climate change, with deforestation alone contributing about 10% of all human-induced greenhouse gas emissions.
Another major driver of the changing climate has been the release of carbon previously stored in the soil, with land degradation between 2000 and 2009 responsible for annual global emissions of up to 4.4 billion tons of CO2, it says.
“Land degradation is a major contributor to climate change, while climate change can exacerbate the impacts of land degradation and reduce the viability of some options for avoiding, reducing and reversing land degradation”, the experts explain.
As a result of more extreme weather, major impacts are to expected, the experts warn: “These include, among others, accelerated soil erosion on degraded lands, increased risk of forest fires and changes in the distribution of invasive species, pests, and pathogens”.
Sustainable land management
But the situation is not irreversible, they say. The solution lays in sustainable land management, meaning reforestation, changes in agricultural practices which would lead to fewer pesticides as well as long-term costs and benefits calculation.
According to the experts, “short-term gains from unsustainable land management often turn into long-term losses, making the initial avoidance of land degradation an optimal and cost-effective strategy”.
They argue that on average, the benefits of restoration are 10 times higher than the costs, with a number of ripple effects: “While challenging, the benefits of restoration include, but are not limited to, increased employment, increased business spending, improved gender equity, increased local investment in education and improved livelihoods.”
But time is scarce, they warn: “An urgent step change in effort is needed to prevent irreversible land degradation and accelerate the implementation of restoration measures”