Where does slash and burn take place?Slash and burn agriculture can take place anywhere there is vegetation to be cut down, burned, and used as fertilizer. The area that the Central Lowland Maya practiced slash and burn in was tropical forest, similar to the forest seen below.
What is the soil like in tropical jungles?The soil of an untouched tropical forest is not as fertile as one might think. In fact, only a thin top layer of soil is rich in nutrients, which is created by the decomposition of fallen foliage from the surrounding vegetation. The soil layers that lie beneath the top layer are usually made up of erosion-prone sand. When vegetation is removed from the area and the topsoil removed, you are left with a piece of land that is waiting to be washed away by frequent tropical rains.
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What happens after the crops are harvested?While slash and burn agriculture provides quick access to cleared land for growing populations, its effects can be devastating to the environment. For example, the direct products of slash and burn are deforestation and soil erosion.
Deforestation is defined as the rate of loss of vegetation or forest being greater than the rate of regrowth. When this happens, environments that were once forested are left without tree canopies. Tree canopies are vital in the collection and deposit of nutrients such as phosphorous, nitrogen, and carbonate compounds. Without these nutrients in the soil, it is very difficult for the forest to regrow and be restored to its former state. (12) Chemical reactions in the soil The net CO2 balance in shifting cultivation is near zero if the forest returns to its original biomass and soil organic carbon status; although there is a small net release of other greenhouse gases during the cropping cycle. Deforestation generally cause’s large losses of CO2 from the soil and vegetation. Greenhouse gas (GHG) emissions are still currently difficult to quantify. Deforestation may lead to changes in evapotranspiration, runoff and local climate but there are few data available to make these determinations. If it occurs in large continuous areas, the rainfall may be decreased, according to modeling studies. (Eckmeier et al. 2007)
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