Research On Climatic Risk Zoning Of Chilling Injuries In South China

Based on the climatic observation data in 224 meteorological stations and chilling injury losses data of hazard bearing body from 1951 to 2006 in South China (Guangdong Province, Guangxi Autonomous Region and Fujian Province), the values of disaster-inducing factors including maximum temperature drop range, extreme minimum temperature, persisting days of low temperature and accumulated harmful chilling during the whole growing season and the process of low temperature weather were calculated. Furthermore, the disaster-inducing factors and the integrated climatic index with the background of climate change of hazard bearing body was constructed, the model of climatic probability estimation and integrated climatic risk zoning were established, the geographical maps of climatic risk probability distribution for each grade chilling injury and integrated climatic risk zoning of hazard bearing body were drawn. There are several main conclusions:1. The processes of chilling injury were used as research scale to construct integrated climatic disaster-inducing factor, which could characterize the occurrence of chilling injury.2. Factors of processes more than 3 days could indicate climatic risk of chilling injury information of the whole growing season, which could be an important basis for dynamic assessment of chilling injury.3. The accumulated harmful chilling for the processes with minimum daily temperature≤Tc and more than 3 days was the factor indicating climatic risk of chilling injury, which was favorable to practical application.4. The results showed that climate warming may lead to the decrease of cold resistance of hazard bearing body, which could increase the disaster risk of chilling injury. The relative accumulated chilling was constructed as integrated climatic index. The results showed that the relative accumulated chilling could better distinguish between chilling injury year and the others.5. Distribution map of mean value of banana, litchi and longan accumulated harmful chilling and distribution map of mean value of tomato and pepper accumulated harmful chilling were drawn. The results showed mean value of accumulated harmful chilling was less than 5℃·d in suitable planting area of banana, litchi and longan, and mean value of accumulated harmful chilling was less than 90℃·d in suitable planting area of tomato and pepper.6. The geographical maps of climatic risk probability distribution for each grade chilling injury (totally 28) and maps of integrated climatic risk zoning of chilling injury (totally 7) of 5 different fruits and vegetables (banana, litchi, longan, tomato, and pepper) were drawn. The results showed that, besides the southern suitable planting area, the northern superiority areas included mainly Bose Prefecture, Guiping of Guangxi, Qingyuan, Xinxing of Guangdong and Zhangzhou, Putian of Fujian. The risks of these areas were obviously lower than those of the same latitude. These areas were suitable for fruits and vegetables cultivation.7. Integrated climatic risk of chilling injury of 5 different fruits and vegetables (banana, litchi, longan, tomato, and pepper) was constructed, which could quantify the risk information of chilling injury. The comparability of risk information was solved, which provided a scientific basis for agricultural production sector to establish suitable disaster prevention and reduction policies and measures.