The problem of desertification is least in which of the following continents ?

Correct — option (1), Europe.

The UN Convention to Combat Desertification, done at Paris on 17 June 1994, defines desertification as land degradation in arid, semi-arid and dry sub-humid areas. By this definition the problem can arise only in drylands, so a continent with little dryland has little room for it.

A 2016 manual published for the Arid Forest Research Institute (AFRI), Jodhpur, gives dryland area by continent in its Table 3.9, citing NAPCD (2001), which its references list as the Ministry of Environment and Forests' National action plan to combat desertification.

In million hectares: Asia 1,837.1, Africa 1,293.3, Australia & Oceania 801.6 and Europe 133.9. The table lists no hyper-arid land in Europe and only 0.5 million ha in its arid category.

Europe's dryland is the smallest of the four by a wide margin, which makes option (1) the continent where the problem is least.

The idea to remember: desertification needs drylands, and Europe has the least dryland.

Why the others are wrong

• (2)
  Australia — AFRI's Table 3.9 gives Australia & Oceania 801.6 million ha of drylands, about six times Europe's 133.9 million ha. The manual names central Australia among the areas where desertification is prevalent along the margins of semi-arid and arid lands.

  Among these four continents, Australia & Oceania has the second-smallest dryland area, after Europe. That is not the least.

• (3)
  Asia — Asia has the largest dryland area of the four: 1,837.1 million ha in AFRI's Table 3.9. The manual states that the extent of drylands is highest in Asia.

  It also states that the impact of desertification on the greatest number of people occurs in Asia, naming degraded areas such as the sand dunes of Syria and the eroded mountain slopes of Nepal.

• (4)
  Africa — Africa has 1,293.3 million ha of drylands in AFRI's Table 3.9, and the table lists 809.9 million ha of hyper-arid land there as well, the largest hyper-arid figure for any continent in the table.

  The manual states that about three quarters of Africa's agricultural drylands are already degraded to some degree. That points to a severe problem, not the least.

The Convention defines the drylands it covers by an aridity ratio. They are areas, other than polar and sub-polar regions, where annual precipitation divided by potential evapotranspiration lies between 0.05 and 0.65.

Its definition of land degradation is a loss of biological or economic productivity of cropland, range, pasture, forest and woodland in those areas. It names processes such as soil erosion by wind or water, deterioration of soil properties and long-term loss of natural vegetation.

AFRI's manual describes desertification as prevalent along the margins of semi-arid and arid lands. It notes that the GLASOD assessment left out hyper-arid regions, treating them as already irreversibly desertified.

Key facts

• UNCCD Article 1: desertification means land degradation in arid, semi-arid and dry sub-humid areas, from factors including climatic variations and human activities.
• Those areas have a ratio of annual precipitation to potential evapotranspiration between 0.05 and 0.65, excluding polar and sub-polar regions.
• AFRI's 2016 manual (Table 3.9, from NAPCD 2001) gives drylands in million ha: Asia 1,837.1; Africa 1,293.3; Australia & Oceania 801.6; Europe 133.9.
• The same table lists no hyper-arid land in Europe and only 0.5 million ha there in its arid category.
• The Convention's text includes regional implementation annexes for the Northern Mediterranean and for Central and Eastern Europe.

Common traps

• Picking Australia because it is dry: in AFRI's table its drylands are about six times Europe's, so its dryness adds to exposure rather than reducing it.
• Treating every kind of soil degradation as desertification: under the Convention, desertification is degradation in drylands, where Europe has the smallest area of the four.
• Reading 'least' as 'none': the Convention has annexes for the Northern Mediterranean and for Central and Eastern Europe.

• practice — not a real PYQ

  Under the United Nations Convention to Combat Desertification, 'desertification' means land degradation in which of the following?

  • (a)Arid, semi-arid and dry sub-humid areas
  • (b)Polar and sub-polar regions
  • (c)Humid tropical forests only
  • (d)Coastal wetlands only
  Answer(1) — Article 1(a) of the Convention defines desertification as land degradation in arid, semi-arid and dry sub-humid areas. Option (2) is excluded by name in Article 1(g); options (3) and (4) name areas the definition does not list.
• practice — not a real PYQ

  According to Table 3.9 of the Arid Forest Research Institute's Manual for Dryland Afforestation and Management (2016), which continent has the largest area of drylands?

  • (a)Africa
  • (b)Asia
  • (c)Australia & Oceania
  • (d)Europe
  Answer(2) — The table gives Asia 1,837.1 million ha. Option (1) has 1,293.3 million ha, option (3) 801.6 million ha and option (4) 133.9 million ha, the smallest.