Keywords
whole-farm model, climate change, irrigation, genetic algorithms
Start Date
1-7-2012 12:00 AM
Abstract
Agricultural systems are vulnerable to climate change (CC). However, by adjustments of their management schemes farmers can minimize negative impacts of global warming on their income. One possibility of assessing adaptation options of agricultural systems to CC is the use of bioeconomic models which link process-based crop growth with economic decision models. In order to account for a wider range of possible adaptation options including changes in land-use or a farm’s business activities, bioeconomic models at farm-scale are required. In this study, a whole-farm model consisting of the crop growth model CropSyst and economic decision model is used in order to assess the effects of CC and different water policies on a crop farm’s total water consumption, the farmer’s utility and on his management decisions with regard to land allocation as well as crop specific nitrogen and irrigation intensities. The represented farm is assumed to be located in the Broye watershed located in Western Switzerland. In this region water scarcity can already be observed in hot and dry summer months due to large water withdrawals for irrigation. In the future CC is expected to further intensify this conflict of water use. Our results show that under CC a crop’s farm total water consumption will increase by more than 240% if irrigation is possible without any restrictions and assuming current water prices. However, both an increase in the water price and the introduction of a water quota would decrease the total water use significantly under current and future expected climate. As a result, the costs for significant reductions in water use of these policies are rather small, i.e. about 11% of their initial utility. Therefore, these measures should be considered by policy makers to cope with CC induced increases in agricultural water use.
Adapting towards climate change: A whole-farm approach
Agricultural systems are vulnerable to climate change (CC). However, by adjustments of their management schemes farmers can minimize negative impacts of global warming on their income. One possibility of assessing adaptation options of agricultural systems to CC is the use of bioeconomic models which link process-based crop growth with economic decision models. In order to account for a wider range of possible adaptation options including changes in land-use or a farm’s business activities, bioeconomic models at farm-scale are required. In this study, a whole-farm model consisting of the crop growth model CropSyst and economic decision model is used in order to assess the effects of CC and different water policies on a crop farm’s total water consumption, the farmer’s utility and on his management decisions with regard to land allocation as well as crop specific nitrogen and irrigation intensities. The represented farm is assumed to be located in the Broye watershed located in Western Switzerland. In this region water scarcity can already be observed in hot and dry summer months due to large water withdrawals for irrigation. In the future CC is expected to further intensify this conflict of water use. Our results show that under CC a crop’s farm total water consumption will increase by more than 240% if irrigation is possible without any restrictions and assuming current water prices. However, both an increase in the water price and the introduction of a water quota would decrease the total water use significantly under current and future expected climate. As a result, the costs for significant reductions in water use of these policies are rather small, i.e. about 11% of their initial utility. Therefore, these measures should be considered by policy makers to cope with CC induced increases in agricultural water use.
