The pie chart illustrates major sources of soil degradation in farming lands all over the world, while the table provides information on this effect in North American, European, and Oceania regions, during 1990s.
Overall, over-grazing is the dominant reason for deterioration of agricultural land productivity, whereas deforestation and over-cultivation are the second and third largest causes, respectively. Moreover, the Europe region accounted for a significant proportion of worldwide land degradation, deforstation being the main cause for this.
In detail, as the predominant reason, excessive livestock feeding caused 35% worldwide degradation during the decade. Deforestation and over-farming accounted for 30% and 28% of soil erosion, respectively.
Considering the regional effect, Europe caused 23% of worldwide land degradation, 9.8% by deforestation, 7.7% by over-farming, and 5.5% by over-grazing. Conversely, excessive cattle feeding was the major source in the Oceania region, being at 11.3%, while clearing the wood cover, served as a reason for 1.7% of degradation. However, over-cultivation has not displayed a visible effect on the Oceania region’s soil erosion. The North American region, being the lowest contributor among the three regions, recorded 0.2% from deforestation, 3.3% from over-cultivation and 1.5% from over-grazing, totalling up to 5% of total land quality deterioration worldwide.