Abstract: Identifying the primary agrometeorological disasters affecting single-season rice in the middle and lower reaches of the Yangtze River, as well as their occurrence patterns and responses to large-scale circulation indices, can provide scientific basis for ensuring secure rice production. We used bibliometric analysis to determine the main types of agrometeorological disasters, critical growth stages, and identification methods for single-season rice in the region. With observational data from 274 meteorological stations and circulation indices from 1990 to 2020, we comparatively analyzed the occurrence characteristics of major disasters during key growth periods and their relationships with circulation factors. Results showed that heat stress, chilling damage, flood, and drought were the dominant agrometeorological threats to single-season rice in the area. Among these factors, heat stress events occurred most frequently, with an average incidence of 1.04 events per year. Spatially, the distribution patterns of severe heat stress and drought zones were consistent, primarily concentrated in the southeastern and southwestern parts of the study area. In these regions, heat stress intensity frequently exceeded 34 °C·d, while drought intensity surpassed 1.94 with chilling damage and flood incidents being less severe. Interannual trend analysis revealed that 92% of stations experienced increased frequency of heat stress events, with magnitude of change exceeding that of the other three disaster types. Chilling damage and drought events showed significant decreasing trends in northeastern areas, with reduction rates generally exceeding 0.25 events per decade. The number of stations reporting increased versus decreased flood occurrences was nearly equivalent. Among the four disaster types, heat stress occurrences had the strongest correlation with the Western Pacific subtropical high intensity, showing significant positive correlations at 52.6% of stations. Chilling damage events generally exhibited negative correlation with high intensity, though only 7.7% of stations reached statistical significance. Responses of flood and drought to this circulation index displayed contrasting patterns between southern and northern regions. These findings would provide valuable insights for guiding single-season rice production strategies in the middle and lower Yangtze River basin.

Key words: the middle and lower reaches of the Yangtze River, single-season rice, agrometeorological disaster, spatiotemporal characteristics, circulation factor