专四听写训练89：Study Finds More Trees on Farms Than
Farmers, especially in developing countries, are often criticized for cutting down forests. But a new study suggests that many farmers recognize the value in keeping trees.
Earlier estimates were much lower but incomplete. The authors of the new study say it may still underestimate the true extent worldwide.
The study found that climate conditions alone could not explain the amount of tree cover in different areas. Nor could the size of nearby populations, meaning people and trees can live together.
There are areas with few trees but also few people, and areas with many trees and many people. The findings suggest that things like land rights, markets or government policies can influence tree planting and protection.