长青国家自然保护区种子植物区系初步分析

来源 :西北植物学报 | 被引量 : 1次 | 上传用户:gbnew
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长青国家自然保护区有种子植物 146 科、730 属、1792 种。对保护区种子植物区系统计分析的结果表明:(1)保护区内种子植物种类丰富,有裸子植物 7 科、16 属、24 种;被子植物139 科、714 属、1768 种。(2)区系成分复杂,属的地理分布类型有 15 个及变型 19 个。其中温带分布占 65.2% ,热带分布占 30.3% ,温带分布占一定的优势,但同时表现出与热带亚热带成分过渡的特点。(3)原始、残遗植物成分较多,表现出保护区植物区系的古老性。(4)有中国种子植物特有属 30
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