海南吊罗山热带山地雨林植物种类多样性研究

海南吊罗山热带山地雨林扫把青冈 鸭脚木群落共出现44个科,95个属的乔木树种190种,其中种类数量大于5个的有樟科(24种),茜草科(17种),山毛榉科(17种),山矾科(11种)和山茶科(11种),主要属为新木姜属(6种),蒲桃属(6种),山矾属(12种)和栎属(13种).群落以热带分布型物种占优势,为895%.其中,又以热带亚洲分布成分最多,占358%;其次是泛热带分布,占274%;其它热带分布型占253%,群落中存在一定比例的温带分布型,约95%,中国特有分布属所占比例极低,仅为11%说明其物种的分化程度较低,同时,也说明山地雨林可能是一个广泛分布于东亚的常绿阔叶林的原始代表类型.样地1共有单个体种45种,双个体种20种,分别占物种总数的304%和135%;样地2共有单个体种46种,双个体种26种,分别占物种总数的383%和217%,这些低密度的或小种群的偶见种相对群落的主要种来说,更容易受到各种胁迫的影响而在群落中绝灭,从而使群落的物种多样性降低.

Biodiversity of Tropical Mountane Rain Forest on Diaoluo Mountain, Hainan

One hundred and ninety species, belonging to 95 genus and 44 families, are recorded in Cyclobalanopsis angustinii Schefflera octophylla community of tropical mountane rain forest on Diaoluo Mountain, Hainan, in which the major families with more than 5 species are Lauraceae (24 species), Rubiaceae (17 spp ), Fagaceae (17 spp ), Smplocaceae (11 spp ) and Theaceae (11 spp ); the major genus with more than 5 species are Neolitsea (6 spp ), Syzygium (6 spp ), Symplocos (12 spp ) and Quercus (13 spp ).Tropical taxon with 89 5% of the total genera is a main geographical component of the flora, of the taxon tropical taxon of Asia is 35 85%, pantropicaltaxon is 27 4% and all the others is 25 3%, only endemic taxon of China of 1 1% and temperate taxon of 9 5% are found The results show that the specialization of the species is low and the tropical montane rain forst is a primitive type of the evergreen forest generally distributed in Eastern Asia Fourty five singleton and 20 doubleton, respectively occupied 30 4% and 13 5% of the total species number, are identified in plot 1; Fourty six singleton and 26 doubleton, respectively accounting for 38 3% and 21 7% of the total species number, are identified in plot 2 These species with low density and small population are more declined to extinct than the dominant species under any disturbance, and lose of the singleton and doubleton species will lead to a low species diversity in the community