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Tundra
Boreal forest
Temperate forest
Temperate grasslands, savannas and shrublands
Desert and dry shrublands
Tropical and subtropical forests
Tropical and subtropical grasslands, savannas and shrublands
Source: adapted from Olson et al., 2001.
Tropical forests hold the largest terrestrial carbon store and are active carbon sinks. Re-
ducing emissions from deforestation and degradation is a vital component of tackling
dangerous climate change. In addition, tackling illegal and ill-managed logging will be
an important part of reducing emissions from forestry.
Tropical forests occupy large areas of central and northern
South America, western Africa, South-East Asia and north-
eastern Australia. Most tropical forests are moist forests,
found in areas where annual rainfall normally exceeds 2000
mm per year and is relatively evenly distributed. Such forests
have extremely high levels of plant, mammal, insect, and bird
diversity and are considered to host the greatest biodiversity of
all the Earth’s biomes.
The warm and wet climate of tropical moist forests results
in rapid plant growth and most of the carbon can be found
in the vegetation, with biomass estimates of 170–250 t C
per ha (Malhi
et al.
2006; Chave
et al.
2008; Lewis
et al.
2009). Tropical moist forests can vary considerably in their
carbon stocks depending on the abundance of the large,
densely wooded species that store the most carbon (Baker
et al.
2004). On average, they are estimated to store around
160 tonnes per hectare in the above-ground vegetation
and around 40 tonnes per hectare in the roots. Soil carbon
stocks are estimated by Amundson (2001) at around 90-
200 tonnes per hectare, and are thus somewhat lower than
biomass stocks.
TROPICAL FORESTS