Evaluation of agricultural climatic resource utilization during spring maize cultivation in Northeast China under climate change

Agricultural climatic resources (such as light, temperature, and water) are environmental factors that affect crop productivity. Predicting the effects of climate change on agricultural climatic resource utilization can provide a theoretical basis for adapting agricultural practices and distributions of agricultural production. This study investigates these effects under the IPCC (Intergovernmental Panel on Climate Change) scenario A1B using daily data from the high-resolution RegCM3 (0.25°×0.25°) during 1951–2100. Model outputs are adjusted using corrections derived from daily observational data taken at 101 meteorological stations in Northeast China between 1971 and 2000. Agricultural climatic suitability theory is used to assess demand for agricultural climatic resources in Northeast China during the cultivation of spring maize. Three indices, i.e., an average resource suitability index (Isr), an average efficacy suitability index (Ise), and an average resource utilization index (K), are defined to quantitatively evaluate the effects of climate change on climatic resource utilization between 1951 and 2100. These indices change significantly in both temporal and spatial dimensions in Northeast China under global warming. All three indices are projected to decrease in Liaoning Province from 1951 to 2100, with particularly sharp declines in Isr, Ise, and K after 2030, 2021, and 2011, respectively. In Jilin and Heilongjiang provinces, Isr is projected to increase slightly after 2011, while Ise increases slightly and K decreases slightly after 2030. The spatial maxima of all three indices are projected to shift northeastward. Overall, warming of the climate in Northeast China is expected to negatively impact spring maize production, especially in Liaoning Province. Spring maize cultivation will likely need to shift northward and expand eastward to make efficient use of future agricultural climatic resources.