湖北兴山县种子植物区系特征与垂直分布格局研究

根据2016年-2017年对兴山县全域进行网格调查所获取的3450份野生种子植物标本, 结合相关标本馆馆藏标本数据, 对兴山县域种子植物区系特征与垂直分布格局进行了研究。结果显示, 兴山县共有野生种子植物145科705属1883种。在科级水平上主要以热带分布型为主, 共有63科, 占总科数的43.45%; 属级水平上温带分布型占据优势地位, 共有379属, 占总属数的53.76%。兴山县种子植物区系特征兼具有温带性质和热带亲缘, 过渡性特征明显, 区系成分复杂。种子植物在垂直分布上主要呈现为三大类: 在海拔100-1000 m范围内主要形成低山常绿落叶阔叶混交林; 在海拔1000-1900 m范围内以中山落叶阔叶林为主; 海拔1900-2500 m范围内形成亚高山灌丛。总体来看, 兴山县种子植物在海拔700-1300 m的中海拔地区物种最为丰富。

Floristic characteristics and altitudinal patterns of seed plants in Xingshan County

The floristic characteristics and vertical distribution pattern of seed plants in Xingshan County were studied based on the combinative data of 3450 plant specimens collected from the whole region of Xingshan County from year of 2016 to 2017 with the grid investigation method,and the specimen information obtained from several herbaria.The results showed that there were 1883 species of wild seed plants in Xingshan County,belonging to 145 families and 705 genera.At the family level,the plant flora were dominated by the tropical taxa,with 63 families taking up 43.45%of the total families;at the genus level,the temperate distribution pattern occupied the dominant position,with 379 genera accounting for 53.76%of the total genera.The seed plant flora of Xingshan County had the characteristics of both temperate and tropical components,implying an obvious characters of transition.The vertical distribution of seed plants was divided into three categories,with evergreen and deciduous broad-leaved mixed forest dominating in the low mountain areas ranging from altitude of 100 m to 1000 m,broadleaved deciduous forest dominating in the middle mountains ranging from altitude of 1000 m to 1900 m,and shrubs dominating in the subalpine regions ranging from altitude of 1900 m to 2500 m.On the whole,the seed plants in Xingshan County had the most abundant species in the middle elevation area ranging from 700 m to 1300 m.