海南五指山野生兰科植物的垂直分布格局

Altitudinal Distribution Pattern of Orchid Plants in Wuzhishan,Hainan

在海南五指山自然保护区核心区选择海拔高度为700～850 m、850～1 000 m、1 000～1 150 m、1150～1 300 m、1 300～1450 m、1 450～1 600 m、1 600～1 750 m、1 750～1 867 m共8个连续的海拔梯度,分别对植物群落中的野生兰科植物进行普查。结果表明,海南五指山野生兰科植物的垂直分布格局呈"中间膨胀型"或"单峰型",随着海拔升高,各海拔段有野生兰科植物依次为20、30、29、24、12、9、7、2种,其中850～1 300 m海拔段的物种多样性较高。对各海拔样点的聚类结果表明,海南五指山野生兰科植物可分为"高山生态分布"、"温凉潮湿型"、"湿热型"、"半干热或干热型"4种生境类型,海拔850 m为五指山野生兰科植物区系垂直分布的分界,是五指山野生兰科植物由热带向亚热带成分过渡的分界线。

Vertical distribution of wild orchid species in Wuzhishan Nature Reserve,Hainan Province was investigated at eight different altitudinal gradients from 700 m to 1 867 m in the centre of the Reserve.It was revealed that the vertical distribution pattern of wild orchid species in the Reserve is ＂intermediate expandable＂ or ＂single peak＂,the number of wild orchids species was in the order of 20,30,29,24,12,9,7 and 2 from low altitude to high with approximately 150 meter for each gradient.More species abundance appeared at elevation of 850～1 300 m;Clustered to samples of eight different altitudinal gradients.Results show that the wild orchid species in Wuzhishan Nature Reserve,Hainan Province can be divided into ＂Ecological distribution of mountain＂,＂cool and wet type＂,＂heat type＂,＂semi-dry heat or dry heat type＂ 4 habitat types,elevation of 850m for the flora boundary of vertical distribution and from the tropical to subtropical boundary of the transition elements.