Source: Brady, N.C. 1996. Alternatives to slash and burn: a global imperative. Agric. Ecosyst. Environ. 58:3-11.

This article focuses on the issues that must be considered in seeking alternatives to slash-and-burn agriculture, or what is also called shifting cultivation. Brady exams the problems of deforestation and greenhouse gas release caused by the slash-and-burn system as well the destruction of a way of life in the tropics by the loss of traditional shifting cultivation systems. The stages in a traditional system are (1) the farmer first burns to clear the land, (2) the land is then cultivated for two to three years before it must be abandoned because weeds have become a problem, and (3) the land is then allowed to return to forest for a period of 10 to 20 years before again being burned and then cultivated. According to Brady, slash-and-burn is sustainable if maintained using traditional methods. As the trees regrow, they replenish soil organic matter and prevent soil erosion. When the trees are burned the nutrients contained in their biomass is returned to the soil. This allows low but relatively constant crop yields. Shifting cultivation has traditionally taken place in small, isolated, rural communities. Population growth in these communities now strains the land's ability to produce enough food, requiring more land to be cleared and shortening the fallow period. Two problems have resulted from this improper use of slash-and-burn. First, burning the forest releases greenhouse gases into the air, and since the land must be burned more often and more of the land must be burned each time to support the population, more greenhouse gases are released into the atmosphere. It is estimated that 25% of global warming is currently due to the burning of tropical forest. The second issue is that by destroying the rain forests some biodiversity is also destroyed, thereby decreasing the likelihood of finding potentially beneficial species in the future. This, like the release of greenhouse gases, occurs in all shifting cultivation systems but is enlarged by the need for more land and the resulting destruction of more forest. Research needs to consider the socio-economic, biophysical, and atmospheric issues that are part of a slash-and-burn system. Socio-economic issues include protection of peoples' freedom through use of traditional methods or alternative agriculture systems. The biophysical issues include ways of increasing crop yield and productivity, improving efficiency, and finding better weed control methods so that the fields are not abandoned as quickly. Atmospheric issues are those that concern the release of greenhouse gases and other air pollutants in the burning of the land. These issues need to be addressed globally to achieve greater security and opportunities for people and to find economic and social alternatives to slash-and-burn agriculture.

Abstract author: Sarah H. Scally, 15 November 1996.

SUSAG Abstracts: Go back to the SUSAG Abstracts search page.