Management of Canadian prairie region grazed grasslands: Soil C sequestration, livestock productivity and profitability

Date

2005-01-06

Authors

Lynch, D.H.
Cohen, R.D.H.
Fredeen, A.
Patterson, G.
Martin, R.C.

Journal Title

Journal ISSN

Volume Title

Publisher

Agricultural Institute of Canada

Abstract

The GrassGro model (a computer simulation of management-induced changes in range and pasture forage and livestock productivity) was combined with spreadsheet analyses to estimate the influence of improved grazing practices on soil organic carbon (SOC), and farm profitability, across native rangelands and tame pastures of the southern Canadian Prairies. Improved practices included complementary grazing (CG) and reduced stocking density (RSD) on rangeland; and N fertilization (FERT), seeded grass/legumes grazed continuously (GLGC) or rotationally (GLGR), and RSD on tame pastures. The analysis was stratified into three ecoregions on the basis of similarities in climate and soil type. Averaged over 30 yr and ecoregions, SOC rates of gain through improved management were 5 (RSD) to 26 (CG) kg C ha–1 yr–1 for rangelands, and 86 (RSD), 75 (GLGC), 62 (GLGR) and 222 (FERT) kg C ha–1 yr–1 for tame pastures. Gains with FERT were considered largely negated by associated energy (C) costs, N2O emissions, and shifts in grassland species. The CG system alone improved net returns to the producer. The estimated potential combined SOC gain on prairie grazinglands (11.5 Mha) was 1.63 MMT CO2 yr–1 (or 0.465 MMT C yr–1), slightly less than the 1.70 MMT CO2 yr–1 currently emitted from agricultural soils in Canada.

Description

We are grateful to Mike Main and Julia Cooper, Nova Scotia Agricultural College, for their assistance in the preparation of this manuscript. Thanks also are due to Drs. Martin Entz, (University of Manitoba), and Marcia Monreal (AAFC Brandon) for sharing their valuable experience with us.

Keywords

Soil carbon, GrassGro model, grazing management, rangeland, tame pasture, Carbone du sol, modèle GrassGro, gestion de la paissance, grands parcours, prairies artificielles

Citation

Lynch, D. H., Cohen, R. D. H., Fredeen, A., Patterson, G. and Martin, R. C. "Management of Canadian prairie region grazed grasslands: Soil C sequestration, livestock productivity and profitability." Can. J. Soil Sci. 85 (2005): 183–192

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