Climate change and critical thresholds in Chinas food security
Identification of critical thresholds of temperature increase is an essential task for inform policy decisions on establishing greenhouse gas (GHG) emission targets. We use the A2 (medium-high GHG emission pathway) and B2 (medium-low) climate change sce-narios produced by the Regional Climate Model PRECIS, the crop model - CERES, and socio-economic scenarios described by IPCC SRES, to simulate the average yield changes per hectare of three main grain crops (rice, wheat, and maize) at 50 km x 50 km scale. The threshold of food production to temperature increases was analyzed based on the relationship between yield changes and temperature rise, and then food security was discussed corresponding to each IPCC SRES scenario. The results show that without the CO2 fertil-ization effect in the analysis, the yield per hectare for the three crops would fall consistently as temperature rises beyond 2.5 °C; when the CO2 fertilization effect was included in the simulation, there were no adverse impacts on Chinas food production under the projected range of temperature rise (0.93.9℃). A critical threshold of temperature increase was not found for food production. When the socioeconomic scenarios, agricultural technology development and international trade were incorporated in the analysis, Chinas internal food production would meet a critical threshold of basic demand (300 kg/capita) while it would not under A2 (no CO2 fertilization); whereas basic food demand would be satisfied under both A2 and B2, and would even meet a higher food demand threshold required to sustain economic growth (400 kg/capita) under B2, when CO2 fertilization was considered.
Wei Xiong Erda Lin Hui Ju Yinlong Xu
Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, P.R. China
国际会议
北京
英文
186-202
2011-09-26（万方平台首次上网日期，不代表论文的发表时间）