Land degradation caused by human activities is driving the world towards a sixth mass species extinction, makes climate change worse, has negative impacts on at least 3.2 billion people and costs the world the equivalent of 10% of annual GDP through lost biodiversity and ecosystems services, according to a report from the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).
The report notes that land degradation is almost always due to multiple interacting factors. Some of the main causes are:
- High-consumption lifestyles in developed economies
- Rising consumption in developing economies
- Human population growth in many parts of the world
- Rapid expansion and unsustainable management of croplands and grazing lands
- Lack of awareness of the seriousness of land degradation
- Separation of consumers and producers due to globalisation, meaning that consumers rarely see the consequences of their consumption choices, while local land management policies may be undermined because of strong influence from elsewhere (e.g. global markets)
The effects of land degradation include:
- Habitat loss leading to biodiversity loss
- Lower productivity of ecosystem biomass and of agriculture
- Critical levels of lost ecosystem services, such as food security, water security and soil fertility
- Disproportionate effects on groups including women, indigenous people and lower-income people
- Desertification, contributing to human migration
The report estimates that the benefits of land restoration are ten times greater than the costs, but notes we must act within the next decade if we are to meet the Sustainable Development Goals. It suggests that the following actions, among others, be taken to halt and reverse land degradation:
- In croplands: reducing soil loss, using salt-tolerant crops, conservation agriculture, integration of crops, livestock and forestry.
- In grazing lands: management of fires and reinstatement of local livestock management practices.
- In wetlands: controlling pollution sources and reflooding wetlands damaged by draining.
- In urban areas: replanting with native species, developing ‘green infrastructure’ such as parks and riverways, remediating contaminated and sealed soils (e.g. under asphalt), treating wastewater treatment and restoring river channels.
Readers may be interested in this recent news story: Europe faces 'biodiversity oblivion' after collapse in French birds, experts warn. See also the Foodsource resource How do food systems affect land-use and biodiversity?