Dynamic adaptation of maize and wheat production to climate change
Agriculture represents the main source of livelihood for small scale farmers, and a significant fraction of the gross domestic product in the case of intensive commercial agriculture. Because crop performance at the end of a growing season is strongly linked to the observed meteorological conditions, agricultural systems have been one of the main subjects of analysis to understand the impacts of both climatic variability and climatic change. As climate scientists make progress understanding the key elements of the atmosphere and provide with better projections of climate change scenarios, more effort is devoted to impact assessment and the evaluation of adaptation strategies to reduce vulnerability of crops and farmers. The objective of this work was to document the impacts of climate change on maize and wheat yields in Chile as well as to describe the dynamics of adaptation (i.e. changes in management decisions over time) that will take place, considering that farmers can “learn” from previous crop yield outcomes. Yield outcomes were obtained using a crop simulation model run under climate change scenarios based on HadCM3 projections. A simple decision model for a risk neutral farmer was used to investigate changes in optimum management decisions over time. Maize showed yield reductions in the order of 5% to 10%. Under irrigation, the best alternative for adaptation corresponded to adjustments in sowing dates. In the case of winter wheat significant yield reductions were observed for the no adaptation case. Because this crop showed positive responses to the increase of carbon dioxide, adaptation strategies were very effective counterbalancing the impacts of a warmer and drier environment. Dynamic adaptation was referred here to the introduction of small adjustments in management based on previous observed changes in productivity. This type of adaptation strategy outperformed prescriptive decisions based on historical or projected climate change scenarios, since it was sufficiently flexible to maintain near optimum economic performance over time, as climate varied from baseline to projected future conditions.
KeywordsClimate Change Winter Wheat Adaptation Strategy Climate Change Scenario Sowing Date
Unable to display preview. Download preview PDF.
- Carlson RE, Todey DP, Taylor SE (1996) Midwestern corn yields and weather in relation to extremes of the southern oscillation. J Prod Agric 9:347–352Google Scholar
- Goudriaan J, Unsworth MH (1990) Implication of increasing carbon dioxide and climate change for agricultural productivity and water resources. In: Impact of carbon dioxide, trace gases and climate change on global agriculture. ASA Special Publication, vol 53. American Society of Agronomy, Crop Science Society of America, and Soil Science of America, Madison, WI, pp 111–130Google Scholar
- IPCC (2001) Climate change 2001: impacts, adaptation, and vulnerability. Contribution of working group II to the third assessment report of the intergovernmental panel on climate changeGoogle Scholar
- Mendelsohn R, Dinar A (1999) Climate change, agriculture, and developing countries: does adaptation matter? World Bank Res Obs 14(2):277–293Google Scholar
- Parry ML (1990) Climate change and world agriculture. Earthscan, LondonGoogle Scholar
- Wilkens PW, Hoogenboom G, Porter CH, Jones JW, Uryasev O (2004) Decision support system for agrotechnology transfer version 4.0. volume 2. DSSAT v4: data management and analysis tools. University of Hawaii, Honolulu, HIGoogle Scholar
- Wilks DS, Wilby RL (1999) The weather generation game: a review of stochastic weather models. Prog Phys Geogr 23(3):329–357Google Scholar