广东8种乡土绿化树种的叶结构型性状研究

Leaf Structure Characteristics of Eight Indigenous Greening Trees in Guangdong

摘要:

为探讨乡土绿化树种对广东边缘热带和南亚热带气候的响应特征,在广州和湛江选取8 种共有乡土绿化树种进行叶片结构型性状研究,分析两地间各性状的异同以及相关性状与叶比重(LMA)间的关系。结果表明,叶片鲜重(FW)、叶长、叶宽、平均宽度以及干重(DW)、叶面积和叶片含水率等在两地存在差异,但并未表现出一致的变化规律;尖叶杜英(Elaeocarpus apiculatus)、印度紫檀(Pterocarpus indicus)、大叶紫薇(Lagerstroemia speciosa)和非洲楝(Khaya senegalensis)两地间的比叶面积(SLA)差异极显著(P<0.001);洋紫荆(Bauhinia variegata)的上、中部叶片厚度(TH),黄葛榕(Ficus virens var. sublanceolata)、大叶紫薇、白兰(Michelia alba)和人面子(Dracontomelon duperreanum)的上部叶片厚度均为广州大于湛江(P<0.05)。LMA与FW和DW呈显著正相关,与叶片含水率呈显著负相关,而与叶面积、叶平均宽度和宽长比并无显著的线性相关关系。这可能是两地的气候条件相差不大,还不足以使乡土树种的结构型性状产生一致性的适应性变化特征。

关键词:广州;湛江;乡土绿化树种;叶片结构;比叶面积;边缘热带

Abstract:

To reveal the effects of edge tropical and lower subtropical climatic conditions on indigenous trees in Guangdong Province, leaf structure characteristics of 8 indigenous greening species in Guangzhou and Zhanjiang were studied. The relationship between leaf mass per area (LMA) and leaf structure characters were analyzed. The results showed that leaf structure characters, i.e., fresh weight (FW), leaf length, leaf width, average leaf width and dry weight (DW), leaf area and leaf moisture content, had significant differences between two cities without consistent pattern. Specific leaf area (SLA) of Elaeocarpus apiculatus, Pterocarpus indicus, Lagetstroemia speciosa and Khaya senegalensis had significant difference between Zhanjiang and Guangzhou (P<0.001), while did not SLA of Michelia alba, Dracontomelon duperreranum, Bauhinia variegata and Ficus virens var. sublanceolata. The thickness (TH) of upper and middle leaves of Bauhinia variegata, upper leaves of Ficus virens var. sublanceolata, Lagerstroemia speciosa and Dracontomelon duperreanum in Guangzhou were larger than those in Zhanjiang (P<0.05). LMA had significantly positive correlation with FW and DW, and significantly negative correlation with leaf moisture content. There were not significant relation between LMA and leaf area, average leaf width and ratio of width to length. The climate conditions of two climate zones in Guangdong are differ litter, which not enough to make consistent adaptive variation of leaf structure characteristics in indigenous greening tree species.

Key words:Guangzhou;Zhanjiang;Indigenous greening tree;Leaf structure;SLA;Edge tropics