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Difficulty: MediumEnvironmental Hazards and Degradation

In the Sudano-Sahelian belt of northern Nigeria, continuous loss of arable land and southward extension of desert-like conditions have severely affected agricultural productivity. Which human activity is the primary driver accelerating this process of desertification?

  1. Uncontrolled fuelwood extraction and persistent overgrazing by livestockAnswer
  2. B
    Extensive industrial effluent discharge into inland river channels
  3. C
    Rapid downhill movement of loose regolith under the direct force of gravity
  4. D
    Improper disposal of non-biodegradable municipal solid waste in urban drainage systems

Answer

Uncontrolled fuelwood extraction and persistent overgrazing by livestock are the primary human activities driving accelerated desertification in northern Nigeria.
In the fragile Sudano-Sahelian zone, natural climatic dryness is greatly exacerbated by human activities. Over-reliance on wood for fuel removes canopy cover and tree roots that stabilize soil, while high stocking densities of livestock strip native grasses. This combined pressure destabilizes soil structure, allowing wind erosion to advance desert-like conditions.

Step-by-Step Solution

1
Identify the geographical context and environmental hazard described in the stem.
The region is the semi-arid Sudano-Sahelian zone of northern Nigeria, and the hazard is desertification (land degradation in drylands).
Understanding the regional ecological parameters helps pinpoint the specific environmental vulnerability.
2
Analyze the primary human drivers of vegetation loss in semi-arid environments.
Deforestation for fuelwood and excessive grazing expose fragile topsoil to severe wind desiccation and water erosion.
Removing biomass breaks the nutrient cycle and accelerates soil crusting and dune movement.
3
Differentiate desertification drivers from other environmental hazard causes.
Industrial pollution, mass wasting, and urban drain blockages cause water pollution, slope failure, and urban flooding respectively.
Eliminating misattributed hazard mechanisms leads to the accurate anthropogenic cause.

Key Concept

Desertification drivers and land degradation in semi-arid regions
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Topics

Environmental Hazards and Degradation

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