The Effects of Weather on Oilseed Rape (OSR) Yield in China: Future Implications of Climate Change

Understanding the role of climatic factors on crop yields is essential in predicting the future impact of climate change. In order to understand the influence of climatic factors on OSR, detailed farm-level panel data from 2566 farms across 67 counties of the 6 major OSR production regions in China, from the surveys conducted by the national OSR industry project between 2008 and 2013, were used to examine the contribution of changes in selected climatic variables between 2008 and 2013 to yield variation. Spatial and temporal patterns of the relationships between OSR yield, climatic factors were estimated together with the effects of farmer adaptation and management practices on yield variability. The analysis revealed that yields in the low-latitude production regions were more sensitive to temperature increases and likely to decline. Precipitation iwas the most influential factor on yield at the first two growth stages; temperature and sunshine hours were most important at the third and fourth growth stages, respectively. Labour input was the most influential management factor affecting yields compared with fertilizer and other inputs. The study concludes that projection of future climate change impacts will need inter alia to incorporate more sophisticated and detailed measures of climatic variables than simple means of temperature and precipitation, incorporating timing in relation to plant growth and yield.