基于功能性状的常绿阔叶植物防火性能评价

植物功能性状不仅便于评价植物的防火性能,也有利于筛选防火植物。本研究以宁波地区的29个常绿木本植物为对象,在测定植物比叶面积、叶干物质含量、叶片含水量、枝条干物质含量和树皮厚度5个功能性状,以及鲜叶的7个防火性能指标的基础上,通过因子分析将防火性能指标划分为抗燃性f_a(包含抗火性因子f₁和燃烧速度因子f₂2个公因子)与燃烧性f_b 2个防火因子,然后利用Pearson相关和偏相关建立了5个功能性状与各个防火因子的相关性,并对29物种的防火性能进行评价。结果表明：1)比叶面积和树皮厚度与抗火性因子f₁,枝条干物质含量、树皮厚度和当年生叶片含水量与燃烧速度因子f₂,比叶面积与抗燃性因子f_a,叶片干物质含量、比叶面积和当年生叶片含水量与燃烧性因子f_b间存在显著的相关关系；2)偏相关简化植物防火性状后,比叶面积和叶干物质含量分别对抗燃性因子f_a与燃烧性因子f_b的指示性最好；3)分别基于功能性状和燃烧试验的物种抗燃性排序相似度为0.80。本研究证明,基于简易观测的植物功能性状可较好地反映树种的抗火性和燃烧性,可作为植物防火性能有效的评价方法。

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 f_a was significantly correlated with SLA, and combustibility factor f_b 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 traitbased and burning experimentbased assessments. In conclusion, easily measurable plant functional traits are useful approach to surrogate and to assess plant fireprofing and combustibility.