The Natural Fix?

TEMPERATE FORESTS

Temperate forests are active carbon sinks and deforestation in the temperate zone has largely stopped. Where demand for land and/or water allows, reforestation would enable carbon sequestration and could provide other benefits including higher biodiversity and recreation opportunities.

of large woody above-ground organs and deep, coarse root sys- tems, accounts for around 60% and soil carbon the remainder (Amundson 2001). HUMAN IMPACTS AND IMPLICATIONS FOR CARBON MANAGEMENT Temperate forests, notably in Europe and North America, have been increasing in extent for several decades. In many areas, current management practices, such as relatively lengthy cut- ting cycles and appropriate fire regimes, have led to an enhanced capacity for carbon storage. In consequence, temperate forests are currently considered to be overall carbon sinks. In Europe, forests are estimated to be taking up 7–12% of European carbon emissions (Goodale et al. 2002; Janssens et al. 2003). Further reforestation and improvements in management could increase carbon sequestration in the short term (Jandl et al. 2007).

Temperate forests are found in climates with four distinct sea- sons, a well-defined winter and regular precipitation. They oc- cupy large areas of Asia, Europe and North America and are found mostly in developed nations. There are many different types of temperate forests, some dominated by broad-leaved trees and others by coniferous species, and they are generally relatively high in animal and plant diversity. Because the soils they generate are often very fertile much of the area once occu- pied by temperate forests has been converted to croplands and pasture and is now used for food production. Plant growth, decomposition and carbon cycling are rapid in temperate forests, with less carbon accumulating in the soil than in boreal forests or tundra. The overall carbon store for these forests has been estimated at between 150 and 320 tonnes per hectare, of which plant biomass, chiefly in the form

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.

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