The pie chart reports information about the causes of reduction of agricultural productivity and the table displays figures about how such causes manifested in three different areas of the world in the last decade of the twentieth century.
Overall, the impact of the three main causes of land degradation is similar on a world scale, but looking at specific areas of the world, it appears that each region is affected by a specific problem. Furthermore, the percentage of land degraded is not distributed homogenously among different world areas.
Worldwide, the main cause of land loss is over-grazing, which accounts for about one third of the toal, shortly followed by cutting down trees and cultivating too many plants, which represent respectively 30% and 28%.
If we consider the percentage of reduction of land productivity in different areas of the world, in North America the majority of the land degradation (3.3% of 5%) is due to over-cultivation, while in Europe to deforestation (9.8% of a total of 23%). Finally, in Oceania over-grazing is responsible for 11.3% of the loss of valuable land, out of a total of 13%. In addition, a remarkable data is that over-cultivation is not an issue in Oceania.