The pie chart below shows the main reasons why agricultural land becomes less productive. The table shows how these causes affected three regions of the world during 1990s.
参考范文：
The main factors responsible for the decreased productivity of agricultural land in North America, Europe, and Oceania during the 1990s were summarized in a pie chart and a table.
the most serious problem was over-grazing. It has caused the world to lose 35% of agriculture land. This problem is followed closely by deforestation and over-cultivation.
The area that has lost most proportion of its agriculture land was Europe at 23% However, Oceania and North America was not as badly affected, losing 13% and 5% of its farmland respectively.
Surprisingly, the main problem faced by each area is different from one another. The problem with over-grazing is especially serious in Oceania, resulting in 11.3% of its land unsuitable for agriculture. On the other hand, deforestation that caused 9.8% of agriculture land unusable was the major problem faced by the European farmers. Although over-cultivation was the primary threat in North America, it was not a problem at all in Oceania.
In conclusion, over-grazing was the main cause of worldwide degradation in 1990s. Europe's percentage of degradation was largest of all three regions and all three regions had different predominant causes.
Total Words: 172
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