Table 1

Residual land carbon sink

Reference
1980's (Pg C/yr)
1990's (Pg C/yr)

Residual land carbon sink
IPCC 2001 [19]
-0.3–3.8
incomplete
House et al. [20]
0.3–4.0
1.6–4.8
Additional land carbon uptake due to increased nitrogen deposition (globally)
Townsend et al. [11]
n/a
0.3–1.3
Holland et al. [12]
n/a
1.5–2.0
This study
0.62–2.33
0.75–2.21
Additional land carbon uptake due to increased nitrogen deposition (temperate forests)
Nadelhoffer et al. [10]
n/a
0.25
This study
0.34–1.62
0.4–1.85

Negative values represent atmospheric CO2 increase (or land sources), positive numbers depict atmospheric CO2 decrease (land sinks).

Churkina et al. Carbon Balance and Management 2007 2:5   doi:10.1186/1750-0680-2-5