Answer: Removal of topsoil by water and wind; accelerated by deforestation, overgrazing, improper agricultural practices; reduces agricultural productivity.
- A Soil gradually becoming progressively richer and more fertile in organic nutrients through ongoing natural decomposition processes according to standard textbooks
- B Removal of topsoil by water and wind; accelerated by deforestation, overgrazing, improper agricultural practices; reduces agricultural productivity
- C Improvement of overall soil structure that is typically achieved gradually through regular composting and consistent mulching practices in general practice
- D Natural formation of new soil layers through the slow, gradual weathering of underlying bedrock over many centuries as frequently described in most textbook accounts
Correct answer: B. Removal of topsoil by water and wind; accelerated by deforestation, overgrazing, improper agricultural practices; reduces agricultural productivity
Explanation: Soil erosion: loss of topsoil (most fertile layer) by water run-off and wind. Accelerated by: deforestation (roots bind soil), overgrazing, monoculture farming, construction. Effects: reduced agricultural productivity, increased flooding, silting of rivers. Prevention: contour ploughing, cover crops, terracing, afforestation, windbreaks.
Sunlight passes through the atmosphere and warms the surface; the surface re-radiates this energy as infrared heat, which greenhouse gases (CO₂, CH₄, water vapour) absorb and trap - a naturally beneficial process that intensifies into global warming as gas concentrations rise from human activity.
Concept context
Pollution, global warming, ozone depletion, deforestation, and sustainability. Important for NEET and general awareness.