Analysis of spatiotemporal coupling relationships and driving mechanisms between climatic factors and winter wheat yield in the Yudong Grain Production Core Area
摘要
Based on meteorological observation data from 24 stations in the Yudong Grain Production Core Area (YDGPC) from 1951 to 2021, the climate-driven yield index (CDYI) of winter wheat from 1983 to 2021, as well as teleconnection factors, this study systematically analyzes the spatiotemporal variation characteristics and driving mechanisms of climate and winter wheat CDYI in the YDGPC. The results indicate: (1) Over the past 70 years, the annual average temperature in the study area has shown a significant upward trend. Combined with Morlet wavelet analysis and Rescaled Range (R/S) analysis indicate that the climate may show a “warm-wet” trend in the short term in the future. (2) Empirical Orthogonal Function (EOF) analysis reveals that both the annual temperature field and annual precipitation field exhibit two modes and four spatial distribution patterns, with their spatial differentiation primarily regulated by geographical location, topographic conditions, and atmospheric circulation. (3) ENSO exhibits a significant 2–7 years resonant period with both temperature and precipitation; SSN has a stronger influence on precipitation than on temperature, showing a persistent significant 11-year resonance phenomenon with annual precipitation. (4) The September sea surface temperature anomaly (SSTA_Sep) is an important precursor signal affecting the winter wheat CDYI in YDGPC. A per unit increase in SSTA_Sep results in a 3.2% decrease in winter wheat CDYI. The research results provide theoretical support and practical guidance for optimizing winter wheat planting systems, early warning of disaster risks, and adaptive climate change management in Yudong.