生物多样性 ›› 2008, Vol. 16 ›› Issue (1): 75-82.DOI: 10.3724/SP.J.1003.2008.07081

• 论文 • 上一篇    下一篇

南岭国家级自然保护区兰科植物物种多样性的海拔梯度格局

田怀珍1,2, 邢福武1,*()   

  1. 1 中国科学院华南植物园, 广州 510650
    2 中国科学院研究生院, 北京 100049
  • 收稿日期:2007-03-15 接受日期:2007-08-15 出版日期:2008-01-27 发布日期:2008-01-27
  • 通讯作者: 邢福武
  • 作者简介:*E-mail:Xinfw@scib.ac.cn

Elevational diversity patterns of orchids in Nanling National Nature Reserve, northern Guangdong Province

Huaizhen Tian1,2, Fuwu Xing1,*()   

  1. 1 South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650
    2 Graduate University of the Chinese Academy of Sciences, Beijing 100049
  • Received:2007-03-15 Accepted:2007-08-15 Online:2008-01-27 Published:2008-01-27
  • Contact: Fuwu Xing

摘要:

兰科是单子叶植物最大的科和被子植物中的第二大科。兰科植物物种多样性的海拔梯度格局因地域或坡向不同而呈不同趋势。南岭国家级自然保护区地处南岭山脉中段南坡, 植物资源丰富。作者对南岭国家级自然保护区兰科植物进行了为期4年的调查, 记录了其种类、数量、生活型、海拔、生境, 分析了其区系成分, 并依据IUCN (2001)濒危物种红色名录及保护区的具体情况对其濒危等级进行了评估。从海拔230-1,902 m, 每200 m分段, 共划分为9个海拔段分析其垂直分布格局。结果显示: (1)实地记录兰科植物38属70种, 大多数种类数量较少, 乳阳管理处的种类最为丰富; (2)随着海拔的上升, 总体兰科植物以及不同生活型的兰科植物物种数量均呈现“中间高度膨胀型”而峰值偏向低海拔的特点; (3)濒危物种主要集中在600-1,000 m人为活动稀少、环境好的小生境中; (4)800-1,000 m的区系成分最丰富, 热带性质的兰花多数分布在海拔1,600 m以下; (5)相邻海拔段的兰科植物种类的相似性系数较高; 海拔段相隔越远, 相似性系数越小。小生境和水分条件对于兰科植物的生长非常重要, 中海拔具有良好的水热条件, 因此物种多样性最高; 而低海拔地区的人为破坏使得该海拔段兰科植物物种的多样性显著降低。

关键词: 兰科植物, 物种多样性, 海拔梯度, 区系成分, 生活型, 濒危等级

Abstract

Abstract: To determine orchid diversity along an elevation gradient, we conducted a four-year investigation at five management districts (Ruyang, Dadongshan, Chengjia, Longtanjiao and Tianjingshan) in Nanling National Nature Reserve, northern Guangdong Province. The orchid species and individual number, their life forms and habitat conditions were surveyed. Then we analyzed their floristic components and evaluated their endangerment degree according to the IUCN Red List Categories and Criteria (IUCN, 2001). To study the altitudinal distribution of orchids, we divided the study area from 230 m to 1,902 m into nine equal belts at 200-m intervals. We recorded 70 orchid species of 38 genera in total, of which 63 species were recorded in Ruyang. Most of these species had small populations. The orchid diversity presented a hump-shaped pattern along the elevational gradient with a peak at mid-elevations (600-800 m), of which terrestrial, epiphytic, and saprophytic orchids showed the same trend. The endangered species were mainly distributed at 600-1,000 m, where there were better habitats and less human disturbance. The most abundant floristic components were found at 800-1,000 m. The tropical orchids mainly distributed below 1,600 m. There was a higher similarity index between the neighbouring elevational belts. It was concluded that the abundant orchid species at mid-elevation resulted from better thermal and humidity condition, while the conspicuous decline of species richness at low elevation is a result of human disturbance.

Key words: orchids, species diversity, elevational gradient, floristic components, endangered categories