Abstract:

Apples are of great importance in the global and Chinese fruit industries. Against the backdrop of climate change, frost disasters during the apple blossom period are occurring with increasing frequency and severity, posing a serious threat to yield and quality. Classification, summarization and systematic analysis were employed in this study. Based on the concepts and indicators that define apple blossom frost in China, it reviewed research progress on frost disaster loss and risk assessment during this critical period, analyzed existing issues and proposed future research priorities. The results show that the single factor about apple blossom frost indicator based on the daily minimum temperature was currently the most widely used. The assessment of frost damage during apple blossom was dominated by statistical models and the integration of various methods had been effective in identifying key disaster-causing factors and constructing loss models. Significant progress had also been made in assessing the impact of frost on yield during apple blossom using the STICS model. The risk assessment of apple blossom frost involved multiple factors and often suffered from subjectivity and uncertainty, with relatively limited research and applications. In contrast, notable achievements had been made in the narrow risk assessment of apple blossom frost and temporal exposure risk assessment. It was projected that frost risks would decrease in the Bohai bay and the southwestern high-altitude of cold regions, while it would increase in the Loess plateau region. While the risk might decrease in Xinjiang production area, the intensity of the frost was expected to intensify. The earlier flowering period of apple trees had been identified as a central cause of increased frost intensity in temperate growing regions. In the future, the construction of comprehensive and localized apple blossom frost indicators and the establishment of multi-model coupled assessment methods will be the core and key approaches for frost loss and risk assessment during apple blossom period in China. 

Key words: Loss assessment, Risk assessment, Mathematical statistics, Crop model