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I am looking for help with IELTS! Feel free to comment on!

The pie chart shows the reasons for a decrease in productivity of agricultural land. It consists of four parts. First and foremost, overgrazing, which degraded 35% of agricultural land. [1] Then we have deforestation (30%), and overcultivation (28%). 7% is attributable to other factors.

The table shows a comparison of the factors described above, which destroyed lands in North America, Europe, and Oceania. Overgrazing became the most destructive factor for the nature, and in a short period of time throughout the 1990’s caused significant degradation of land, from 1.5% in North America up to 11.3% in Oceania. The second worst factor was deforestation, with a 9.8% impact in Europe, and a much lesser percentage of influence in other geographical regions.

The third reason – overcultivation – had a zero impact in Oceania, but at the same time the highest impact compared to other causes in North America; and an average of 7.7% in Europe.

With a total of 23%, agricultural land in Europe was the most degraded in the 1990’s. In contrast to this, North America had only 5% of degraded land.

Thank you for any corrections!

[1]  My corrections are based upon my understanding that you wish to state the percentage of agricultural land that has been degraded by various causes.  If I am mistaken, tell me, and I'll try again.