The pie chart and accompanying table elucidate the primary factors contributing to the decline in agricultural land productivity, alongside the specific impacts of these factors across three distinct regions during the 1990s.
Overall, over-grazing, deforestation, and over-cultivation emerged as the predominant causes of land degradation globally, with Europe experiencing the most significant total degradation among the regions studied.
The pie chart illustrates that over-grazing accounts for the largest share of agricultural land degradation at 35%, followed closely by deforestation at 30% and over-cultivation at 28%. Collectively, these three causes represent 93% of the total, leaving a mere 7% attributed to other factors. The subsequent table provides a breakdown of land degradation percentages in North America, Europe, and Oceania, highlighting the varying impact of these culprits across these regions during the 1990s.
In Europe, the total degradation was recorded at 23%, with deforestation and over-cultivation responsible for 9.8% and 7.7%, respectively. Oceania experienced a significant 13% degradation, predominantly due to over-grazing, which constituted 11.3% of the total. Notably, over-cultivation had no observable effect in Oceania, which may indicate a more favorable environmental condition, such as sufficient water supply. In stark contrast, North America exhibited the least degradation, with only 5% total land affected—comprised of 0.2% from deforestation, 0.3% from over-cultivation, and 1.5% from over-grazing