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Every year, more people face poverty and hunger and more of the earth's resources are ruined. The problems are enormous, but many experts believe that the situation is not hopeless. The solution will require big changes in how we think about agriculture, food, and our planet. First of all, farmers everywhere need to develop methods that are less destructive to the environment. The change from single crop farming to a mixed crop system would be one important step. The planting of several different crops improves the soil and helps prevent erosion. Erosion could also be prevented by planting trees to protect the fields from the wind. Another way farmers could improve the soil is to avoid deep plowing. In fact, only a slight plowing is necessary if proper methods are used. If the soil were treated better, farmers would not need to use chemical fertilizers. They could use natural animal and vegetable products instead. With mixed crops, farmers would need fewer toxic chemical insecticides. They could use biological methods of controlling insects and disease.