The pie chart illustrates the most important reasons for low productivity in agricultural land and the table gives information about three regions namely, North America, Europe and Oceania which faced these causes during 
the 
1990. Change the article
apply
Overall
, the highest and lowest percentage of over-grazing and other reasons is 35% and 7% respectively.
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deatail
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detail
although
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the deforestaion
deforestaion
 proportion was lower than over-grazing Correct your spelling
deforestation
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it was Remove the conjunction
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a
 main reason in Europe with Correct article usage
the
the 
23% of total Correct article usage
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degraded
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degradation
thus
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highest
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the highest
in 
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Furthermore
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Ocenia
 the rate of over-cultivation was zero which means it was not an Correct your spelling
Oceania
issues
 in Correct the article-noun agreement
issue
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Hence
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another
 causes Correct quantifier usage
other
such
 as over-grazing was more effective with 11.3%.
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Finaly
, 5% of total land degraded Correct your spelling
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blongs
 to north america given that, Correct your spelling
belongs
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the deforstation
deforstation
 rate was lower than Correct your spelling
deforestation
other
 Change preposition
in other
casuse
 and it was 0.2% until 1990.Correct your spelling
causes