2020
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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20%
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40%
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30%
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60%
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Detailed explanation-1: -Wetlands contain a disproportionate amount of the earth’s total soil carbon; holding between 20 and 30% of the estimated 1, 500 Pg of global soil carbon2 despite occupying 5–8% of its land surface3. The anoxic conditions characteristic of wetland soils slow decomposition and lead to the accumulation of organic matter.
Detailed explanation-2: -Although oceans store most of the Earth’s carbon, soils contain approximately 75% of the carbon pool on land - three times more than the amount stored in living plants and animals.
Detailed explanation-3: -Wetlands occupy about 2–6% of the Earth’s land area, but store 20–30% of the Earth’s terrestrial soil carbon [8]. Global wetland soil organic carbon (SOC) is about 202.0–535.0 Pg [9], and the Chinese wetland carbon pool has been estimated to be about 5.0–6.2 Pg [10].
Detailed explanation-4: -A fifth of the Earth’s wetlands have been destroyed by humans over the past three centuries, a cumulative area larger than India, a comprehensive new study has found.