Evaluation and spatial distribution of tea plant heat injury risk

Risk of tea plant heat injury (RTHI) varies with geographical factors. To get a better understanding of the geographical factors determining RTHI variability, support vector machines were used to analyze relationships between RTHI and selected geographical factors. The results showed nonlinear relationships between RTHI and geographical factors. High values of RTHI were found in central Zhejiang province. In mountainous areas, RTHI values decreased with altitude, with values of 0 at altitudes above 530 m. Because of low altitude and surrounding mountains preventing hot air from circulating between the inside of basin areas and outside, RTHI values were high in the middle of basins. Water bodies with larger surface areas reduced RTHI values. Our results suggest that RTHI increases with climate warming; therefore, it is necessary to take into account local geographical factors and select suitable tea plant planting and management techniques to reduce the impact of heat waves on tea production.