GEF

Unit 3  |  Primary Sustainability Issues 72 challenge is in the long and expensive process of receiving offi- cial organic certification, which can present significant barriers to some farmers. The integration of agriculture into natural ecosystems is another successful approach to sustainable farming. Many farmers have learned to preserve strips of natural habitat in and around farm fields, reaping the benefits provided by native insects that pollinate crops and control pests. A related method is agroforestry , in which farmers intersperse crops with stands of trees, increasing yield, preventing erosion, increasing biodiversity, and providing a supply of timber and other products. A study in Malawi showed that corn plots inter- spersed with nitrogen-fixing trees yielded more than three times as much as plots that did not incorporate trees. The systems approach of agroforestry and similar methods represents a long-term solution to the challenge of sustainable agriculture. Agroforestry can increase yield, prevent erosion, increase biodiversity, and provide a supply of timber. AGROFORESTRY A sustainable farming method in which farmers intersperse crops with stands of trees, increasing yield, pre- venting erosion, increasing biodiversity, and provid- ing a supply of timber and other products.