非胎生红树植物繁殖体特征与分带关系

利用分带值的方法调查了海南东寨港和清澜港的红树林群落结构组成状况,比较了4种非胎生红树植物(瓶花木、海漆、榄李和老鼠簕)的繁殖体散布特征(大小、质量和漂浮性)和萌发的初始时间和萌发率的情况.4种非胎生红树植物在潮间带的位置从海到陆依次是:瓶花木、海漆、榄李和老鼠簕.繁殖体的大小按长度依次是榄李>老鼠簕>瓶花木>海漆,按质量依次是老鼠簕>榄李>瓶花木>海漆.瓶花木和榄李有很好的漂浮性,其次是海漆,老鼠簕的漂浮性最差.榄李的种子具有休眠的特点,因此萌发实验用50 d湿处理对榄李进行解除休眠.盐度高于30时榄李不能萌发,而老鼠簕对盐度具有很好的耐受性,在30盐度以下,萌发率都很高,甚至达到了100%.4种非胎生红树植物繁殖体的散布特征和萌发情况,对于了解红树植物在潮间带的分带现象有重要意义.

Relationship Between Diaspore Traits and Inter-tidal Zonation of Non-viviparous Mangrove Species

Sequencing scores of four non-viviparous mangrove species (Scyphiphora hydrophyllacea Gaertn.,Excoecaria agallocha L.,Lumnitzera racemosa (Jack.) Voigt.,and Acanthus ilicifolius L.) were obtained from mangrove communities in Dongzhai harbor and Qinglan harbor in Hainan.The differences in dispersal properties such as length,mass,buoyancy and germination of these four non-viviparous mangrove species were investigated.Distribution order of these species from low to high inter-tidal zones were S. hydrophyllacea, E. agallocha, L. racemosa, A. ilicifolius.The order of diaspore longevity was L. racemosa>A. ilicifolius>S. hydrophyllacea>E. agallocha,while diaspore masses were in the order of A. ilicifolius>L. racemosa>S. hydrophyllacea>E. agallocha.Among these four non-viviparous species,diaspore buoyancy was in the descending order of S. hydrophyllacea>L. racemosa>E. agallocha>A. ilicifolius.Due to seed dormancy of L. racemosa,the propagules for germination were stored in wet condition for 50 d.Propagules of L. racemosa failed to germinate at salinities over 30. Propagules of A. ilicifolius were more tolerant to high salinity than those of L. racemosa.It was even with 100% germination at salinities less than 30.Diaspore dispersal characters of these four non-viviparous species are important in understanding the phenomenon of mangrove zonation in inter-tidal zone.