There is evidence of reduction of biomass in Saskatchewan's boreal forests[13] (as with those of other Canadian prairie provinces) is linked by researchers to drought-related water stress, stemming from global warming, most likely caused by greenhouse gas emissions. While studies, as early as 1988 (Williams, et al., 1988) have shown climate change will affect agriculture,[14] whether the effects can be mitigated through adaptations of cultivars, or crops, is less clear. Resiliency of ecosystems may decline with large changes in temperature.[15] The provincial government has responded to the threat of climate change by introducing a plan to reduce carbon emissions, "The Saskatchewan Energy and Climate Change Plan", in June 2007.