Presenter/Author Information

Marion Sautier
Roger Martin-Clouaire
Michel Duru

Keywords

grassland, vulnerability, exposure, climate, simulation

Start Date

1-7-2012 12:00 AM

Description

Research on the potential impact of weather, including its year-to-yearvariability, and on climate change effects on agricultural systems requires a clearappreciation of their exposure to the related hazards. Usually exposure is assessedthrough analysis of temporal patterns of physical variables (e.g. temperature,precipitation). The method presented in this paper provides a means of fitting thesedata into an intelligible frame specific to the grassland-based livestock systemsmotivating this work. The basic idea consists in quantifying the seasonal balancebetween herbage growth and livestock feeding requirements, considering aroughly-defined type of grassland systems differentiated on soil type, vegetationtype and management practices. Based on a daily growth computer model, theproposed computational method yields several indicators pertaining to the temporalboundaries of three periods called seasons (spring, summer+fall, and winter) and,for each of them, to the balance between herbage production and animal feedrequirements. The boundaries of the seasons vary from one year to another andare defined with respect to the daily average available herbage in a grasslandsystem that is assumed balanced (i.e. in which the herbage production meets theanimal demand over a sufficiently long period). The indicators defining seasons andsurplus-shortage balance are easy to grasp and are highly instructive for scientists,farmers and policy makers. This method, applied to future weather time series,makes it possible to detect potential impacts (positive or negative) of climatechange on herbage production and its seasonality in livestock systems.

Share

COinS
 
Jul 1st, 12:00 AM

An Intelligible Assessment of Climatic Exposure of Grassland-based Livestock Systems

Research on the potential impact of weather, including its year-to-yearvariability, and on climate change effects on agricultural systems requires a clearappreciation of their exposure to the related hazards. Usually exposure is assessedthrough analysis of temporal patterns of physical variables (e.g. temperature,precipitation). The method presented in this paper provides a means of fitting thesedata into an intelligible frame specific to the grassland-based livestock systemsmotivating this work. The basic idea consists in quantifying the seasonal balancebetween herbage growth and livestock feeding requirements, considering aroughly-defined type of grassland systems differentiated on soil type, vegetationtype and management practices. Based on a daily growth computer model, theproposed computational method yields several indicators pertaining to the temporalboundaries of three periods called seasons (spring, summer+fall, and winter) and,for each of them, to the balance between herbage production and animal feedrequirements. The boundaries of the seasons vary from one year to another andare defined with respect to the daily average available herbage in a grasslandsystem that is assumed balanced (i.e. in which the herbage production meets theanimal demand over a sufficiently long period). The indicators defining seasons andsurplus-shortage balance are easy to grasp and are highly instructive for scientists,farmers and policy makers. This method, applied to future weather time series,makes it possible to detect potential impacts (positive or negative) of climatechange on herbage production and its seasonality in livestock systems.