UPSC Prelims Practice Questions — Breaking up forests is just as bad for global warming

Q1. Satellite-based studies report the following: (i) fragmentation raises surface temperature in tropical and temperate forests; (ii) fragmentation lowers surface temperature in boreal forests where more snow-covered open ground is exposed; (iii) above-ground biomass density is lower near forest edges than in forest interiors. Which of the following inferences can be drawn from the above?

  1. The direction of the local temperature response to fragmentation depends on the surface that replaces the canopy, not merely on the loss of trees.
  2. Fragmenting boreal forests is, on balance, beneficial for the climate.
  3. A forest-cover statistic alone cannot reveal the local thermal and carbon consequences of how forest patches are arranged in a landscape.
  4. In tropical and temperate forests, fragmentation warms the surface because the exposed ground reflects more sunlight than the canopy.
  • A. 1, 3 and 4 only
  • B. 1 and 3 only
  • C. 2 and 4 only
  • D. 1 and 2 only

Q2. With reference to edge effects in forests, consider the following statements: Which of the statements given above is/are correct?

  1. Forest edges are, on average, cooler than forest interiors because the better ventilation at edges increases evaporative cooling.
  2. The temperature difference between forest edges and interiors varies with biome and season.
  3. Higher temperature, higher precipitation and a larger share of surrounding agricultural land are associated with more negative edge effects on above-ground biomass.
  • A. 1 and 3 only
  • B. 1 and 2 only
  • C. 2 and 3 only
  • D. 1, 2 and 3

Q3. With reference to 'forest cover' as assessed in the India State of Forest Report, consider the following statements: Which of the statements given above is/are correct?

  1. A privately owned orchard of more than one hectare with tree canopy density above 10 per cent can be counted as forest cover.
  2. An increase in reported forest cover does not by itself show that existing forest blocks have become more contiguous.
  3. Land is counted as forest cover only if it is a recorded forest area under forest law.
  • A. 2 only
  • B. 1 and 3 only
  • C. 1, 2 and 3
  • D. 1 and 2 only

Q4. Consider the following assertion: Rising national forest-cover figures can coexist with a decline in the climate-regulating value of forests. Which of the following statements support/supports the above assertion?

  1. Above-ground biomass density is, on average, lower near forest edges than in forest interiors.
  2. The degree of fragmentation of a forest can change local surface temperature as much as total forested area does.
  3. In summer, surface temperature at forest edges frequently exceeds the optimum for vegetation productivity, particularly in tropical forests.
  4. FAO's Global Forest Resources Assessment 2025 places India ninth in the world in total forest area.
  • A. 1, 2 and 3 only
  • B. 1, 2, 3 and 4
  • C. 2, 3 and 4 only
  • D. 1 and 2 only

Q5. Consider the following statements: Which of the following is correct in respect of the above statements?

  1. India's NDC commitment on forests is framed as an additional carbon sink in CO2-equivalent terms, rather than as a target share of geographical area under forest.
  2. Tree cover outside forests is excluded from the additional carbon sink that India counts towards this commitment.
  • A. Both Statement-I and Statement-II are correct and Statement-II explains Statement-I
  • B. Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
  • C. Statement-I is correct, but Statement-II is incorrect
  • D. Statement-I is incorrect, but Statement-II is correct

Q6. A new highway is to cut through the middle of a large contiguous forest block. The forest land diverted for the road is to be offset by planting an equal area of forest on degraded land in another district. In this context, consider the following statements: Which of the statements given above is/are correct?

  1. Planting an equal area of forest elsewhere restores the contiguity of the original forest block.
  2. The highway creates new forest edges along both sides of its alignment, increasing the share of edge forest in the original block.
  3. Since net forest area is conserved, the highway's effects on local surface temperature and on biomass in the original block are neutralised.
  • A. 1, 2 and 3
  • B. 2 and 3 only
  • C. 2 only
  • D. 1 only

Q7. Two forest landscapes have exactly the same total forest area. In Landscape P the forest is one compact block; in Landscape Q the same area is split into many small, separated patches. Compared with P, Landscape Q would most likely have:

  • A. A larger share of forest near edges, and higher average above-ground biomass density
  • B. A larger share of forest near edges, and lower average above-ground biomass density
  • C. The same share of forest near edges, and the same average above-ground biomass density
  • D. A smaller share of forest near edges, and higher average above-ground biomass density