The causes of farmland degradation

The pie chart presents four main reasons leading agricultural land to low yield. And the table illustrates a statistics about the situations of lands in three countries, which is affected by the mentioned causes.

The pie chart shows that over-grazing is the dominant reason causing land degradation, which takes 35%. Deforestation is close behind with 30%, and the influence from over-cultivation is listed 3rd with 28%. Other factors only account for 7%.

In the 1990s, the degradation of land in Europe was most serious, with 23% of total land degraded throughout the period. Oceania came next with 13% and North American ranked 3rd with 5% in total. Deforestation made up the largest percentage of 9.8% in Europe, followed by over-cultivation (7.7%) and over-grazing (5.5%). In contrast, only 0.2% of degraded land was due to deforestation in North America, while over-cultivation and over-grazing took larger proportions of 3.3% and 1.5% respectively. In Oceania, a lmost all land degradation was caused by over-grazing (11.3%). However, over-cultivation never appeared in Oceania over these years.

As can be seen, over-grazing, over-cultivation and deforestation lead to/result in more than 90% of degraded land, which have different influences on the three mentioned countries.