【摘要】 银叶树HeritieralittoralisDryand是一种既能生长在潮间带,也能在陆地上生长的"两栖性"红树植物。由于过度采伐和开辟鱼塘等人为原因,加上城市化、环境污染和由其导致的病虫害等,使银叶树生长立地条件被破坏,数量锐减。中国现存的野生银叶树种群(成年个体数在20株以上)仅见于深圳盐灶、海丰香坑、海南清澜港和广西防城港。通过调查及研究,发现中国现有银叶树的实际分布面积不足30hm2,且呈岛屿状分布;个体数不足3000,其中,成年个体数不足1000,且还在减少;多数种群幼树及中等个体数少,呈一定的瓶颈现象;自然情况下,产种子少,种子萌发率低,幼苗向成苗转化率低。因此,中国银叶树已处在严重受威胁状况,亟需进行保护和物种恢复。更多还原

【Abstract】 Heritiera littoralis is a characteristic constituent of back mangrove, which can grow in both intertidal wetland and inland. Due to the urbanization, pollution, and overexploitation for wood, fodder, and fishing_pond, the stands of Hlittoralis decreased markedly all over the world during the past half_century. In China, natural populations of Hlittoralis having more than 20 individuals can only be found in Yanzao of Shenzhen, Xiangkeng of Haifeng, Qinglan harbor of Hainan, and Fangchen harbor of Guangxi. Our investigation showed that the actual colonization area of Hlittoralis was less than 30 hm~2 in China, and the distribution presented an island pattern. The total number of individuals was less than 3 000 and decreasing continually, of which less than 1 000 represented the mature. For most populations, there were few seedlings and middle age individuals showing bottleneck somewhat. The seed production of Hlittoralis was low in nature, and so was the germination rate as well as the transformation rate from juvenile to adult. In conclusion, the survival of natural populations of Hlittoralis in China has been threatened seriously, it is high time to take effective actions to preserve this species and its habitats in_situ.更多还原