Abstract:

Based on the long−term homogeneous data of 17 national meteorological stations in the Hexi corridor from 1961 to 2024, this study analyzed spatiotemporal variation characteristics of effective accumulated temperature of ≥10℃, water heating value, sunshine hours and cumulative precipitation and temperature before harvest during the potential growing period of wine grapes using trend analysis, mutation test and change difference test. The impact of key meteorological factors on the climate quality of wine grapes was assessed to provide a scientific basis for adapting wine grape cultivation to climate change in the Hexi corridor. The results showed that thermal resources had significantly improved, effective accumulated temperature of ≥10℃ showed a significant upward trend (6.1℃·d·y⁻¹, P<0.01) from 1961 to 2024. There was a mutation around 1997, the average effective accumulated temperature during the potential growing period increased from 1169℃·d to 1408℃·d, and improved the climate quality of wine grapes from average to excellent level. Water heat value also showed a significant upward trend (11.6℃·mm·y⁻¹, P<0.01), and multiple thresholds were broken during the potential growth period of wine grapes, leading to adverse effects on the climate quality of wine grapes in Zhangye, Jinchang, Wuwei and other areas. Sunshine resources had become abundant and continuously optimized (2.7h·y⁻¹, P<0.01). The trend of increasing temperature and sunlight was particularly evident in low−altitude areas, which had a positive significance for the quality formation of wine grapes. The overall climate quality of wine grapes had improved in the Hexi corridor, with significant increases in the Jiuquan, Gaotai and Wuwei areas on the eastern side of the Qilian mountains. The area of suitable planting had expanded to the east, while there had been a slight decrease in the southwestern mountainous areas. The study had shown that climate change had a significant threshold effect and characteristics of regional differentiation on the climate quality of wine grapes. The increase in heat and light resources in the Hexi corridor were the dominant factors in improving the climate quality of wine grapes. However, excessive warming and an increase in water heat can also increase the risk of a decline in the climate quality of wine grapes.

Key words: Hexi corridor, Wine grapes, Climate change, Climate quality, Climate risk