The given pie chart demonstrates the major reasons why agricultural land becomes less productive, whereas the bar chart represents the impact of these causes on three different regions of the world in the 1990s.
Overall, a considerable percentage showed over-grazing, which was the most significant factor of causing land degradation, while salinisation represented the lowest figure. Among the regions, Europe experienced the highest effect of land degradation, meanwhile, North America accounted for the lowest percentage of land pollution
The highest figure of land degradation was over-grazing, which accounted 34%. The second-largest proportion was deforestation, making up just 30%. A similar proportion followed by over-cultivation at 28%. In contrast, salinisation was the lowest figure and accounting for only 8%.
Turning to the regional figures, Europe had the most significant percentage, accounting for 21,7% of the total, with deforestation at 8,4%, over-cultivation with similar proportion at 7,7% and the remaining proportion was over-grazing at 5,6%. Compared with Europe, percentage of North America was significantly lower, at 7,8%, with deforestation being the leading category at 3,0%, over-cultivation at 3,3% and the lowest one was over-grazing at 1,5%. Meanwhile, Oceania making up 13,6%, with the highest percentage of over-grazing.