The pie chart shows the leading causes of worldwide farmland degradation. The table shows the level of impact of the three main causes in three different regions of the world as a percentage of the total land in each region in the 1990s.
From the pie chart, it can be seen that most of the productivity loss in agricultural land around the world is caused by either over-grazing, deforestation or over-cultivation in roughly equal ratios. The table reveals that the main causes and the proportion of total land affected differ significantly between the three regions.
Europe suffered 23% total land degradation, much higher than Oceania and North America (13% and 5% respectively). It also had the highest figure for deforestation (almost 10%), and its figures for the other two causes were not too much lower (7.7% and 5.5%).
Oceania had the highest ratio for over-grazing (11.3%) – representing almost all of its degraded land, with very little deforestation and none caused by over-cultivation. In contrast, North America’s land was predominantly affected by over-cultivation (3.3%), followed by over-grazing to a significantly lesser extent (1.5%), and lastly by deforestation.