CR 54:233-247 (2012)  -  DOI: https://doi.org/10.3354/cr01131

ABSTRACT: We used improved datasets on both climate and crop production to investigate climate trends during the crop growing period and their impacts on yields of major crops (rice, wheat, maize and soybean) in China by county, during 1980−2008. We found clear regional climate trends during this period, particularly for temperature. Such trends have had measurable impacts on crop yields, with a distinct spatial pattern. For the entire country, the planting area-weighted average showed that climate trends from 1980−2008 reduced wheat, maize and soybean yields by 1.27, 1.73 and 0.41%, respectively, while increasing rice yields by 0.56%. As a result, climate trends as a whole reduced wheat and maize production by 3.60 × 10⁵ t and 1.53 × 10⁶ t, respectively, and increased rice and soybean production by 7.44 × 10⁴ t and 4.16 × 10³ t, respectively. Estimates of climate impacts are smaller than previous estimates that used different scales, datasets and methods. The particular crops and regions that have been most affected and should be priorities for adaptation are maize and wheat in arid and semi-arid areas of northern and northeast China, where droughts induced by increases in temperature and solar radiation could limit the benefits of improved thermal conditions. Climate warming decreases crop yields by accelerating crop development rate, and thus reducing crop growth duration and yield accumulation, and by increasing temperature extremes and heat stress.

KEY WORDS: Climate change · Impacts and vulnerability · Sensitivity · Adaptation · Agriculture