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Across Africa, weak enforcement of environmental laws has hurt its forests, with illegal logging depleting vast woodlands.

Now the huge demand for commodity crops globally also risks increasing the pressure on tropical forests across sub-Saharan Africa, a new study shows. Over the last decades, small and medium-scale farming largely drove agricultural expansion into tropical forests. But growing multinational investments in industrial plantations also contributed to deforestation, and to the social and environmental impacts that come with it.

The study, published in the Environmental Research Letters, analyzed the impact of crop expansion in 25 tropical-forest countries in Africa. Increased production of cocoa, palm oil, soy, sugarcane, maize, rice, coffee, and tea have made countries along the Congo Basin forests—besides Sierra Leone, Liberia, and Côte d’Ivoire— the most vulnerable.

The threat to forests is largely influenced by the move of harvesting for export-oriented commodities from South America and Southeast Asia to Africa. An abundance of land, lax land regulations, and cheap labor has contributed to large-scale landholders acquiring 22.7 million hectares of land across sub-Saharan Africa in the last decade. From 1980-2000, 95% of the cropland expansion in Africa replaced forest.

Population and income growth also affected the demand for agricultural products in countries like Nigeria, Kenya, Ghana, and Sierra Leone. Pressure from governments to increase food production, feed their hungry, and increase revenue also damaged forests. For instance, the Southwest region in Cameroon is a major cropland, 86% of which is forested. Yet the government wants to boost palm-oil production by about 65% by 2020, from 270,000 metric tons to 450,000. Cameroon also hopes to become a global leader in cocoa production by increasing output to 600,000 tons in 2020 from the current 235,000.

Every year, Africa loses about four million hectares of forest land. The impact on the Congo Basin, second in size only to the Amazon, has proved devastating, affecting income opportunities for locals, undermining conservation, and upsetting a wide array of plants and wildlife.

But there’s still hope: Almost two-thirds of Africa’s agriculturally suitable land is still under forest, representing nearly 30% of tropical forest globally. And instituting protective policies, aligning policymakers and farmers, and setting up remote-sensing and monitoring techniques could help lower deforestation rates in the long run.