Management of rice production systems to increase productivity

2.1.3. Environmental Concerns of Upland Rice Cultivation
The main upland rice cropping system is slash‐and‐burn shifting
cultivation with a bush fallow of 3‐5 years. Rice is grown as the first crop after
virgin forest or after long‐term fallow. Upland rice cultivation raises a lot of
environmental concerns, because it involves destruction of forest fauna and
flora, and also permits soil erosion in the process of shifting cultivation. Bush
fires are a common result of slash‐and‐burn cultivation. The environmental
concerns for growing upland rice is far greater than that of other annual crops.
Policy makers, scientist and the public are increasingly concerned about
deforestation in The Gambia and its negative consequences, such as climate
change, biodiversity loss, reduced timber supply, flooding, erosion, siltation,
and soil degradation. Population and migration both affect deforestation
rates, but in a complex fashion that it cannot be simply concluded by saying
that population growth promotes deforestation. Major doubts remain
regarding the relationships between deforestation and productivity growth,
input prices, land markets, land and forest tenure security, and household
income (poverty) that can only be resolved through future research
(Kaimowitz and Angelsen, 1998).
Forests are cleared by burning, in order to create new fertile land for
rice cultivation. This undoubtedly contributes to build‐up of carbon in the
atmosphere, part of the ʹgreenhouse gasʹ effect. Forests act as a sponge
sheltering fragile soils from the extremes of torrential rain in the wet seasons
and searing heat in the dry seasons. There is ample evidence that the removal
of trees enhances flooding and is often followed by drought. In short, tree
removal intensifies the extremes of the tropical climate, initiating a
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