Functional trait-based evaluation of plant fireproofing capability for subtropical evergreen broad-leaved woody plants

Functional trait-based approach is convenient for evaluating plant fireprofing capability, and is also vital for selecting fireprofing plant speices. In the present study, five plant functional traits, including specific leaf area (SLA), leaf dry matter content (LDMC), current year leaf water content (CYLWC), branch dry matter content (BDMC) and bark thickness (BT), and seven indices of fireproofing capability in fresh leaf materials were measured for 29 evergreen broad- leaved plants in Ningbo. Seven indices of fireproofing capability were grouped into two factors involving burning resistence (f_a) (including burning resistence factor f₁ and burning velocity factor f₂) and combustibility (f_b), and then related to each of five plant functional traits. Finally, the fireproofing capability was assessed. The results showed: 1) burning resistence factor f₁ was significantly correlated with SLA and BT, burning velocity factor f₂ was significantly correlated with BDMC, BT and CYLWC, burning resistence factor fa was significantly correlated with SLA, and combustibility factor fb was significantly correlated with LDMC, SLA and CYLWC. 2) SLA and LDMC were effective indices indicating f_a and f_b, as functional traits being simplified by partial correlation. 3) Similarity index was 0.8 for plants' fireprofing rank between trait\ based and burning experiment \ based assessments. In conclusion, easily measurable plant functional traits are useful approach to surrogate and to assess plant fireprofing and combustibility.