Study on the Combustion Characteristics of Seven Common Broadleaf Plant Species in Southern China

Due to the frequent occurrence of forest fires worldwide, which cause severe economic losses and casualties, it is essential to explore the mechanisms of forest fires. In this study, seven common broadleaf plant species from southern China were selected to observe their microscopic structural parameters. The combustion performance parameters of the leaves of these seven species were measured using a cone calorimeter, and the relationship between the microscopic structure and combustion performance was analyzed. Additionally, factor analysis was used to study the combustion intensity factor (F1), fire resistance intensity factor (F2), and the comprehensive fire risk degree (F) of the leaves of the seven plant species. Finally, regression analysis was performed between the microscopic structural parameters and the comprehensive fire risk factor. The results show the following: (1) The ratio of spongy mesophyll to palisade cells (S/P) affects the combustion performance of plant leaves. (2) The ranking of the comprehensive fire risk factor for the leaves of the seven plant species is as follows: Osmanthus fragrans var. semperflorens (OFS) > Cinnamomum camphora (CC) > Loropetalum chinense (R. Br.) Oliv. (LC) > Pterocarya stenoptera C. DC. (PS) > Loropetalum chinense var. rubrum (LCVR) > Photinia beauverdiana C. K Schneid. (PB) > Styphnolobium japonicum (L.) Schott (SJ). (3) There is a strong exponential relationship between the comprehensive fire risk factor and the microscopic structural parameters. This study is beneficial for selecting fire-resistant tree species and monitoring species with higher comprehensive fire risk.