An empirical model for estimating carbon sequestration on the Canadian prairies

Abstract

P. 2005. An empirical model for estimating carbon sequestration on the Canadian prairies. Can. J. Soil Sci. 85: 549-556. There is a need to develop verifiable algorithms that can be easily applied to estimate carbon sequestration in soils. A simple process-based empirical model, driven primarily by soil texture and crop residue input, was developed to account for changes in soil organic carbon (SOC) in Chernozemic soils on the Canadian prairies. The model was used to estimate SOC change under no-till and continuous cropping compared with conventional tillage and rotations with fallow. Using this model, C sequestration due to continuous cropping compared with fallow-containing rotations was determined to be 0.09 Mg C ha -1 yr -1 for the Brown and Dark Brown, and 0.05 Mg C ha -1 yr -1 for the Black and Dark Gray/Gray soil zones. The rate of C sequestration as a result of continuous cropping was positively related to the frequency of fallow, which decreases on the prairies from the Brown, Dark Brown, and Black to the Dark Gray/Gray soil zones. Using this model average C sequestration when conventional tillage was converted to no-till, was 0.13, 0.23, 0.34, and 0.25 Mg C ha -1 yr -1 for the same soil zones, respectively. Combined gains due to no-till and continuous cropping in comparison with conventional tillage and fallow-containing rotations were determined to be 0.22, 0.32, 0.39, and 0.30 Mg C ha -1 yr -1 for the Brown, Dark Brown, Black and Dark Gray/Gray soil zones, respectively. Based on Agricultural Census of Canada data in 1996 and 2001, the amount of "C sequestered" due to the adoption of no-till was estimated to be 1.23 million Mg of C in 1996 and 1.72 million Mg of C in 2001, which is approximately 10% of the total greenhouse gas emissions from the agricultural sector in Canada. This simple process-based empirical model could serve as a useful tool for soil scientists to use in assessing soil sustainability and C sequestration in the Canadian prairies. It would also assist policy makers in understanding how various scenarios of improved management will influence future greenhouse gas emissions on agricultural soils. , ce qui correspond à environ 10 % des émissions globales de gaz à effet de serre de l'agriculture canadienne. Ce modèle empirique simple pourrait s'avérer utile aux spécial-istes de la science des sols qui souhaitent évaluer la pérennité des sols et la séquestration du carbone dans les Prairies canadiennes. Il aiderait aussi les auteurs de politiques à comprendre l'incidence des diverses méthodes visant à améliorer la gestion des terres sur les futures émissions de gaz à effet de serre par les terres cultivées. For personal use only.

Soils and food sufficiency. A review

“…Similar to the data from the US, the positive impact of residue mulch and NT farming on the SOM pool have been reported by several studies in Canada Campbell et al, 2007;Janzen, 2006;Wang et al, 2006;Liang et al, 2005;Singh and Malhi, 2006;Gregorich et al, 2006). These conclusions of improvements in soil quality are also supported by the data from Europe and Australia.…”

Effects of afforestation and deforestation on boreal soil carbon stocks—Comparison of measured C stocks with Yasso07 model results

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Strategies for reducing the carbon footprint of field crops for semiarid areas. A review

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“…With regards to crop residue management, numerous studies from the Canadian prairies have shown that soil Table 6 Average annual production, total energy input, energy output, net energy production, and energy use efficiency measured as grain yield per unit energy input and as the ratio energy output/ energy input for conventional, conservational, and organic cropping systems in the Canadian Prairies [1982][1983][1984][1985][1986][1987][1988][1989][1990][1991][1992][1993] Also identified are the duration of the study and the publication from which the data was obtained organic matter is largely influenced by tillage and crop rotations (summerfallow versus no-till cropping) and less influenced by crop species (Liang et al 2002;Liang et al 2005;McConkey et al 2003).…”