Chapter 3 Measuring biophysical quantities and the use of ... - TEEB

This highlights the importance of taking a multi-service approach to economic valuation takingaccount of trade-offs over ecosystem services, space and time.3.3 A regulating service: global carbon sequestrationEcosystems play an important role in determining atmospheric chemistry, acting as both sourcesand sinks for many atmospheric constituents that affect air quality or that affect climate bychanging radiative forcing. This ability of ecosystems to modify the climate forms the ecosystemservices of climate regulation. Carbon sequestration, the removal of carbon from the atmosphereby the living phytomass of ecosystems, is an important component of this climate regulationservice. In the map below (Figure 3) carbon sequestration was modeled as the net annual rate ofatmospheric carbon added to existing biomass carbon pools, using a proxy of net carbon exchange(NCE) produced in simulations using the Terrestrial Ecosystem Model (TEM) developed byMcGuire et al. (2001) and applied by Naidoo et al. (2008). The model simulates carbon exchangebetween the atmosphere and terrestrial biosphere on the basis of vegetation types, soils, climate,atmospheric CO2, and land use history.Naidoo et al. (2008) point to the limitations of using a model based rather than observationalapproach and the reliance on assumptions, time series and input variables. However, together withthe possibility of assigning economic values to the tons of carbon sequestered, Balmford et al.(2008) point to the possibilities presented by these land-use-coupled models to estimatedifferences in carbon storage, emissions and sequestration under different scenarios (e.g. McGuireet al. 2001). This would make it possible to map the economic value of these services of globalclimate regulation, and how they might change under different scenarios of ecosystem and landuse change.31