Comparison of the Impacts of Climate Change on Potential Productivity of Different Staple Crops in the Agro-Pastoral Ecotone of North China

The aim of this study is to compare the impacts of climate change on the potential productivity and potential productivity gaps of sunflower (Helianthus annuus), potato (Solanum tuberosum), and spring wheat (Triticumaestivum Linn) in the agro-pastoral ecotone (APE) of North China. A crop growth dynamics statistical method was used to calculate the potential productivity affected by light, temperature, precipitation, and soil fertility. The growing season average temperature increased by 0.47, 0.48, and 0.52℃ per decade (p0.05) for sunflower, potato, and spring wheat, respectively, from 1981 to 2010. Meanwhile, the growing season solar radiation showed a decreasing trend (p0.05) and the growing season precipitation changed non-significantly across APE. The light-temperature potential productivity increased by 4.48% per decade for sunflower but decreased by 1.58% and 0.59% per decade for potato and spring wheat. The climate-soil potential productivity reached only 31.20%, 27.79%, and 20.62% of the light-temperature potential productivity for sunflower, potato, and spring wheat, respectively. The gaps between the light-temperature and climate-soil potential productivity increased by 6.41%, 0.97%, and 1.29% per decade for sunflower, potato, and spring wheat, respectively. The increasing suitability of the climate for sunflower suggested that the sown area of sunflower should be increased compared with potato and spring wheat in APE under future climate warming.