Potential impacts of climate change on grazing capacity of native grasslands in the Canadian prairies

Relationships between climate and native grassland production in the Canadian prairies were modelled and used to estimate the potential impacts of climate change on grazing capacity. Field measurements of production were related to climate variables and water balance estimates using regression analysis. Historical time series showed that year-to-year production is most closely correlated with annual actual evapotranspiration, whereas geographic patterns revealed that average production is most closely related to the annual water deficit. Climate and production estimates from the US Great Plains represent potential analogues for the Canadian prairies in the 2050s. Analysis of geographic patterns using Canadian and US data showed that production can be related to actual evapotranspiration (Model 1) or the ratio of actual to potential evapotranspiration (Model 2). The proportion of warm-season (C4) grasses has a significant effect on production in these models. A third independent model (Model 3) using US pr...