Land degradation

The International Soil Reference and Information Centre (ISRIC), in the Netherlands, estimates that since 1945 Homo sapiens has degraded 17 percent of the world's land, not counting wastelands like Antarctica and the Gobi Desert. Two thirds of the devastated area will require major restoration.

According to the IPBES (2018) report, 43% of world populations live in regions affected by land degradation. The problem is growing most rapidly in sub-Saharan Africa, Asia and South and Central America. The report predicts that the combined effects of land degradation and climate change will have displaced between 50 million and 700 million people by 2050, potentially triggering conflict over disputed land. However, it would be wrong to infer that land degradation is purely a problem for developing countries. Overall, land is more degraded in richer nations in the developed world – as shown, for example, by greater declines in soil organic carbon content (a measure of soil health) and probably related to industrial farming. And while the rate of degradation has slowed, people in these regions are generally less vulnerable to its effects.

1. Land degradation has reduced fertility and agricultural potential. Replacing lost top soil takes centuries or even millennia. These losses have negated many of the advances made through expanding agricultural areas and increasing productivity.

1. The USA has the most carefully measured soil in the world. Every five years the U.S. Department of Agriculture evaluates the nation's land, county by county, in terms of something called "the universal soil loss equation," which assesses the soil movement in a given area. In the 1980s three independent studies used the data to estimate actual soil loss. All concluded that the peril to U.S. agriculture from erosion is negligible.

   Even in Africa, the problem is bad luck, bad weather, and bad planning. Traditionally, African villagers held land in common, with access regulated by unwritten cultural rules. In those circumstances the people responsible for the management of the land take overuse into account, so they enforce rules of access that limit the use of the land. When modern crops and agricultural techniques appear, the system comes apart, because yields shoot high enough to give people a greater incentive to cheat. Population pressures exacerbate the problem by shrinking everyone's share of the common land. Add drought or ethnic conflict and the result is disaster. But African nations without drought or conflict have done increasingly well. The 1992 harvest in Nigeria was the biggest in twenty years. Given half a chance, people in Africa seem to make their own way.

   As for other parts of sub-Saharan Africa, no one denies the famine there. Yet recent independent studies have found no long-term environmental consequences of the recent and devastating drought; the southern border of the desert, one study shows, is in about the same place it was eighty years ago, suggesting that the desert expands and contracts with little regard for its human inhabitants. The drought may have led to temporary overuse of common property, but the proper response would be to adjust land-use rules – change the zoning, so to speak – as societies did in other parts of Africa. That this has failed to occur in sub-Saharan Africa says more about the pervasive corruption, inefficiency, and civil turmoil there than about the inherent evils of breeding.

1. Resource demands of the built environment
2. Natural environment degradation
3. Irreversible depletion of natural capital
4. Degradation of material resources
5. Disastrous consequences of war

1. Soil degradation
2. Land rehabilitation difficulty
3. Destruction of wetland environments
4. Destruction of agricultural land
5. Degradation of cultivated land systems
6. Clearance of vegetation
7. Blighted land use

1. Vulnerability of protected natural areas
2. Infertile land
3. Destruction of land productivity

1. Plant pests
2. Natural environmental degradation from recreation and tourism
3. Man-made disasters
4. Land misuse
5. Introduction of high-yield crop varieties
6. Increasing proportion of land surface devoted to urbanization
7. Wildfires
8. Feral mammals
9. Environmental impacts from mining
10. Environmental hazards from logging
11. Disrespect for the land
12. Defective land use planning

1. Endangered public reserves

1. Rehabilitating degraded land
2. Improving land
3. Developing sustainable land use policy
4. Destroying land resources
5. Degrading agricultural resources
6. Conserving land resources

1. Land
2. Destructiveness
3. Degradation
4. Damage

1. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES)
2. Worsening Worldwide Land Degradation Now ‘Critical’