粤西沿海地区半红树植物群落组成和分布及其影响因子研究

半红树植物通常生长于红树林向陆边缘、不规则高潮可及的生境。由于自然分布的限制和人类活动干扰的影响,对半红树植物的分布格局、群落组成和立地条件等方面的了解比较有限,导致目前对半红树植物的保育和管理还有明显缺陷。以粤西沿海地区17处典型半红树植物群落为研究对象,分析了半红树植物种群分布、生境特点、生境面临的威胁及其保护对策。在野外调查中,发现3处中国大陆银叶树(Heritiera littoralis)和玉蕊(Barringtonia racemosa)种群新分布点,以及广东省科级植物分布新纪录--须叶藤科(Flagellariaceae)。研究结果表明,粤西沿海地区半红树植物群落以海漆(Excoecaria agallocha)、黄槿(Hibiscus tiliaceus)、水黄皮(Pongamia pinnata)和银叶树为优势种,伴生种和陆生植物分别以露兜簕(Pandanus tectorius)和楝(Melia azedarache)较为常见,半红树植物群落物种组成主要受土壤盐度和淹水条件影响,自河口的上游至下游逐渐变化,其土壤环境特征与真红树植物群落相似,表现为低盐度(土壤盐度为0.84‰~6.59‰)、土壤酸化(pH为6.01~6.09)和高有机质含量(总有机碳质量比为19.12~44.44 g/kg)的特征。现阶段对半红树植物仍然缺乏综合研究,其包括碳存储在内的生态功能有待进一步研究;同时,半红树植物保护地位在国内尚未明确,建议开展建立保护小区、实施迁地保育和人工恢复等保育手段。     

Annotation on Mangrove Plants

This paper reviews and discusses the technical terms and definition of mangrove and lnangal, as well as mangrove plant. The word mangrove has been used to refer either to the constituent plant of tropical and subtropical intertidal community or to the community itself but this usage makes mote confusion. Being leaved mangrove in the more limited sense for the constituent plant species, mangal was proposed by MacNae (1968) as a term for mangrove community, which has been universally applied to most previous studies and should be adopted now. Mangrove should be therefore defined as a tropical and subtropical tree restricted to intertidal zones, which possesses some morphological specializion and physiological mechanism adapted to its habitat, and mangal as a tropical and subtropical forest community restricted to marine intertidal zones and periodically inundeated by the tides, A new term “consortive plant” is proposed here for herb. liana, epiphyte or parasite, which is restricted in the strict mangrove habitat.