CR 32:219-227 (2006)  -  doi:10.3354/cr032219

ABSTRACT: The World Food Studies crop model (WOFOST) was tuned and validated with observed meteorological data as well as winter wheat growth and yield data for 50 stations in 12 provinces in China from 1998 to 2003. The results show that most of the simulated growth dates and yields lie within ±15% range of the observed data, showing that the genetic parameters determined are reasonable in most winter wheat regions of China. Overall, the results demonstrate that the WOFOST model predicts potential winter wheat yields (assuming there are no limits imposed by water availability) and growth reasonably well under current climatic conditions. By assuming winter wheat varieties and agricultural practices stay constant, the parameterization obtained by the tuning was then used to model the impacts of climate on winter wheat growth for the 50 stations using long-term weather data from 1961 to 2000. Over this period, the simulated potential yield of winter wheat in northern China increased by 2.3%, while decreasing by 1.6% in southern China. In northern China, the accumulated negative temperatures during winter increased by 29.3°C decade^–1, which is most likely the main reason for the increased potential yield of winter wheat. In southern China, one possible reason for the decreased potential yield is a shortened growth interval for winter wheat caused by the increasing mean temperatures.

KEY WORDS: Crop growth model · WOFOST · Climate change · Winter wheat · China