二酸化炭素肥沃化効果を考慮した気候変動による穀物影響評価

抄録

The purpose of this study is to evaluate climate change impacts on crop production, which will be the basic information of analyzing world trade of agricultural commodities, and to help decision makings against potential uncertain problems. In this paper, we calculated change in potential productivity of rice, winter wheat and maize (tropical cultivation) between in 1990 and in 2100 based on the 11 GCM outputs combined with several CO2 emission scenarios and probable range of global temperature increase. Calculation was conducted by using a potential crop productivity model. The results were aggregated into 30 countries/regions. The direct effects of increasing CO2 concentration (CO2 fertilization) as well as the impacts due to global warming are considered. The major outcomes of the model calculations are summarized as follows:
1) Considering CO2 fertilization, the potential productivity of rice and maize will increase in 2100 under the changed climate. As for winter wheat, regions at high latitudes gain higher yield and those at low latitudes loses its yield. Especially decrease in the productivity of winter wheat in India region may be serious.
2) Comparing results with CO2 fertilization and those without it, it was found that most part of increases in potential productivity of rice and maize are derived from CO2 fertilization, not so much from climate change.