西北干旱荒漠区植物属的区系分析

为了分析西北干旱荒漠区种子植物属的组成及其区系特点 ,探讨其起源与演化 ,作者根据多年的调查结果并查阅大量相关资料 ,研究表明 :西北干旱荒漠区分布有种子植物 4 84属 ,其区系特征为单种属、寡种属多 ,优势现象明显 ;植物区系具有强烈的旱生性和古老性 ;区系地理成分复杂多样 ,包含 1 4个分布区类型和 1 4个变型 ,地中海区 -西亚 -中亚分布、北温带分布、旧世界分布、中亚分布类型占据前四位 ,分别占总属的 2 2 .33%、1 7.98%、1 0 .6 9%、7.36 % ;特有成分比较低 ,中国特有成分仅 6属 ,只占总属数的 1 .5 7% ;起源古老 ,多为本土发生

Floristic analysis of spermatophyte genera inthe arid deserts area in North-West China

In order to analyse the composition and the feature of spermatophyte genus in the arid deserts area in North-West China and explore its origin and evolution, according to a long-term survey results and ample relevant data, the authors concluds that the seed plants distributed in the arid desert area are 848 genera, whose flora feature is dominated by one-seeded and depauperate genera, with marked superior phenomenon; the flora owns strong xeromorphy and antiquity; the floral geographical composition is complex and diversified, covering 14 distribution zones and 14 variable types, with the distributions of the Mediterranea, West Asia to Central Asia, North Temperate, Old World Temperate, Central Asia, coming to the first four places, with respective percentages of 22.33%, 17.98%, 10.69%, 7.36%; the particular components take up lower percentage and have only 6 Chinese endemic genera, take up 1.57% of the total; mostly taking place indigenously with ancient origin.