喀喇昆仑山和昆仑山地区禾本科植物区系(英文)

The floristic of the family Gramineae of Karakorum and Kunlun area, China

喀喇昆仑山和昆仑山地区的禾本科植物除去栽培种类外共有 47属 ,含 1 61种。分析表明 :( 1 )本区的禾本科植物主要是由北温带成分组成 ,并兼有丰富的旧世界温带成分和其他温带成分 ,温带性质明显。 ( 2 )本区所分布的泛热带成分无一例外地都能够延伸到温带地区 ,应属一类具有一定程度温带性质的泛热带分布类型。一些种类如蔗茅 (Erianthusravennae)的出现是从地中海地区经中亚分布到本区的。 ( 3)本区的禾本科植物绝大多数属于温寒地带分布类型 ,因而具有明显的高原、高山植物区系的特征 ,主要有固沙草属 (Orinus)、看麦娘属 (Alopecurus)、披碱草属 (Ely mus)、三毛草属 (Trisetum)、扇穗茅属 (Littledalea)、偃麦草属 (Elytrigia)、冠毛草属 (Stephanachne)和拟沿沟草属 (Paracolpodium)等 ,这是本区的高山特化和寒旱化适应现象在禾本科植物中的突出表现。 ( 4 )本区无特有属 ,特有种亦较少 ,这种现象是有其自然和历史原因的。大多数的单种属和寡种属都是从它们各自广布的近缘属中衍生而来 ,表明本区系是一个年轻的、衍生的区系。例如细柄茅属 (Ptilagrostis)之从针茅属 (Stipa) ,钝基草属 (Timoria)之从芨芨草属 (Achnatherum)等。 ( 5 )本区系同周围区系的联系广泛 。

There are 47 genera and 161 species of Gramineae except the cultivated species in the area of the Karakorum and Kunlun Mountains. The results of research on the distribution of the genera and species of Gramineae in the Karakorum and Kunlun Mountains show that (1) The Gramineae mainly contains elements of North Temperate, rich Old Word Temperate and other Temperate. It is obvious that the floristic nature of Gramineae in the Karakorum and Kunlun Mountains is the North Temperate; (2) All Pantropic genera can stretch to the Temperate Zone in this region, which all parts of the Pantropic type are the Temperate nature to a certain degree. For example, Erianthus ravennae from mediterranean to the Karakorum and Kunlun Mountains through the Central Asia; (3) As most genera of Grasses are the type of Temperate and the Frigid Zone, they have distinct floristic characteristics of mountainous and plateau flora such as Orinus, Alopecurus, Elymus, Trisetum, Littledalea, Elytrigia, Stephanachne and Paracolpodium etc. All of these indicate adaptive phenomenon of alpine specialization and cold xerophilization on Grasses in this area; (4) Endemic genus of Gramineae is absent due to its nature and history and the endemic species are also rare in the Karakorum and Kunlun Mountains. Most of the genera with one or fewer species have originated from its relative and widespread genera, such as Ptilagrostis from Stipa, Timouria from Achnatherum , and so on; (5) Flora of the Karakorum and Kunlun Mountains is most closely related to the flora of Tibet, and is also extensively to its adjacent areas.