Question

Read the following statements (I - III) related to slash and burn agriculture and select the correct statements ?

I. In this type of cultivation, the patch of land once cultivated is not used for agriculture again.
II. Due to loss of fertility in the soil the cycle of cultivation in subsequent years becomes less.
III. It is responsible for deforestation.

• A. I and II
• B. II and III
• C. II only
• D. I and III

Answer 1

The correct option is B II and III

Slash and burn agriculture or Jhum cultivation (shifting cultivation) involves clearing land by destroying and burning all the trees on it, farming there for a short time, and then moving on to clear a new piece of land. Hence statement I is incorrect.

The vegetation is typically cleared by fire, and the ashes contribute to the soil's fertility by adding potash (fertilizer). But continuous burning of the land reduces the amount of moisture and removes the humus (the organic matter in the soil). Therefore, it affects its fertility. Due to loss of fertility in the soil the cycle of cultivation in subsequent years becomes less. So the farmer moves to a new patch of the forest for cultivation. Hence statement II is correct.

Slash and burn agriculture contributes to deforestation due to the following reasons :

• In this method the farmers after some cycle of cultivation leave the area alone for several years to allow its recovery. But this recovery is very slow due to increasing population and repeated cultivation.
• In this method fires intentionally set can unintentionally spread throughout the forest. When fire spreads to unintended areas, the protective forest canopy is destroyed. The resulting sun exposure to the forest floor intensifies the existing fire.
• Soil erosion, landslides and dust clouds (due to burning) also leads to deforestation. As without trees and their root systems, soil washes away during heavy rains. Hence statement III is correct.