Shifting cultivation is an agricultural system, in which plots of land are cultivated temporarily then abandoned and allowed to revert to their natural vegetation, while the cultivator moves on to another plot. The period of cultivation is usually terminated when the soil shows signs of exhaustion or, more commonly, when the field is overrun by weeds. The length of time that a field is cultivated is usually shorter than the period over which the land is allowed to regenerate by lying fallow.
Among the shifting cultivators, many use a practice known as “slash-and-burn” as one element of their farming cycle. Others employ land clearing without any burning, and some cultivators are purely migratory and do not use any cyclical method on a given plot. Sometimes no slashing at all is needed where regrowth is purely of grasses, an outcome not uncommon when soils are near exhaustion and need to lie fallow.
There are a number of benefits that urge farmers to choose a practice of shifting cultivation in their agricultural plan. Clearings of field encourage the growth of a variety of species of plants, thus attracting birds and animals. Abandoned lands also continue to provide the community with animals and other forest plants. In well-controlled shifting cultivation, a small plot of land is cleared and the vegetation is used to provide nutrients to the soil. The soil remains fertile for a few years to allow farming. When the fertility of the land depreciates, farmers will move to new areas and occupy another land. The abandoned plot of land is regenerated to increase its fertility again. In other words, once the land becomes inadequate for crop production, it is left to be reclaimed by natural vegetation, or sometimes is converted to a different long-term cyclical farming practice. It is believed that this well-controlled practice does not cause lasting damage to the land. Namely “slash-and-burn” technique is believed to be a sustainable practice and differs from commercial farming, because once the trees are burned, there is very fertile fine ash that deposits along the hummus, meaning that by the time the other fields are burned, the soil has time to reassemble nutrients, in order to make cultural activity possible.
However, there have been debates that shifting cultivation fuels deforestation in many areas. It is also said that it does not provide enough food to meet the demands of a growing population. The practices of shifting cultivation in many parts of the world take place in rather extravagant and unscientific form of land use that cause tangible environment losses. The negative effects of abusing shifting cultivation are devastating and far-reaching in degrading the environment and ecology of the affected region. These negative effects can be identified in the form of localized deforestation, soil and nutrient loss, and invasion by weeds and other species. The indigenous biodiversity is likely to be affected to a large extent. Many environmentalists and agricultural experts researched this topic and ended up strongly opposing shifting cultivation and accusing it of destroying forest resources, being uneconomical, leading to destruction of watersheds, erosion, desertification, and other environmental threats.
References
sciencedaily.com
thestudyofearth.blogspot.se
en.wikipedia.org