Evaluating livestock mobility as a strategy for climate change mitigation: Combining models to address the specificities of pastoral systems
Aurore Vigana,*, Jacques Lasseurb, Marc Benoitc, Florent Mouillotd, Maguy Eugènec,
Laura Mansardc, Mathieu Vignea, Philippe Lecomtea, Céline Dutillya
a CIRAD-UMR SELMET, TA C/112 Campus de Baillarguet, 34398 Montpellier, France
b INRA-UMR SELMET, 2 Place Viala, 34060 Montpellier, France
c INRA-UMR Herbivores 1213, Theix, 63122 St Genès-Champanelle, France
d CEFE UMR 5175, CNRS-Université de Montpellier-Université Paul-Valery Montpellier-EPHE-IRD, 34293, Montpellier Cedex 5, France
Abstract
Pastoral farming systems have always adapted to the seasonal availability of forage resources and climate variability by moving animals. However, the role of animal mobility as a possible mitigating strategy in response to climate change has not been clearly documented. To understand this role, we investigated (i) the major methodological challenges linked to the diversity of grazing areas and other forage resources exploited by these systems and enteric emissions of methane; (ii) the impacts of grazing practices (carbon sequestration/emission) on soil and biomass carbon fluxes. We developed an approach based on two existing models (OSTRAL: Outil de Simulation du TRoupeau ovin ALlaitant and CASA: Carnegie Ames Stanford Approach) that we adapted and used in combination. This approach was applied to three French Mediterranean sheep and crop farming systems with Dierent degrees of flock mobility (sedentary, single transhumance and double transhumance). The preliminary results produced by the whole farm model OSTRAL showed that two systems (sedentary and double transhumance) causing low carbon emissions. In the sedentary system, higher animal productivity offsets the increase in GHG emissions (in CO2eq) caused by feed production. In the pastoral system, grazing reduced total GHG emissions (in CO2eq). The CASA model proved to be useful to simulate the carbon balance under dynamic land cover in natural environments, whether used for grazing or not. This model can help assess the impact of grazing practices and carbon Fluxes in systems linked to natural environments. The results of the Flrst application showed that seasonal mobility of livestock increases the contribution of rangeland to feeding systems and improves the non-renewable energy balance of the system. It is thus extremely important to include the specificities of animals grazing in rangelands outside the structural limits of the farm when evaluating GHG emissions.
Corresponding author.
E-mail address: This email address is being protected from spambots. You need JavaScript enabled to view it. (A. Vigan).
http://dx.doi.org/10.1016/j.agee.2017.03.020
Received 17 February 2016; Received in revised form 11 March 2017; Accepted 20 March 2017
0167-8809/ © 2017 Elsevier B.V. All rights reserved.
