【摘要】 目前关于盐胁迫对红树植物同一植株进行生态、生理及解剖学三个尺度的综合性研究较少。在盐度分别为0、5、10、15、20、30、40和50(‰)条件下种植无瓣海桑(Sa)和泌盐灌木桐花树(Ac)的1年生幼苗,以株高、基径、生物量、叶片数量、叶片长宽及生物量为生态指标;以净光合速率、气孔导度、蒸腾速率及叶绿素含量为生理指标;并采用石蜡切片法观察其叶片横切面解剖结构,系统揭示盐胁迫对两种红树植物在不同尺度上的影响。实验结果表明:(1)盐度的提高在一定范围内能够促进Sa与Ac的生长,但在高盐度(≥30)条件下两种植物均无法存活;(2)Sa和Ac叶片的净光合作用速率、气孔导度和叶绿素含量均呈现出先增加再降低的趋势;(3)无瓣海桑在15、20盐度、桐花树在0、5盐度时,栅栏组织层数最多。由此可知,Sa适宜作为人工湿地建群种和优势种种植,Ac生长旺盛但增高不大,适宜作为伴生种种植。揭示了红树植物的耐盐性机制,可为人工红树林湿地构建和恢复红树林生态系统提供理论依据。更多还原

【Abstract】 Limited information exists, however, concerning the effects of salt stress on both of the ecological, physiology and morphology indexes of mangrove plant reaction. We treated 1 year old seedlings of Sonneratia apetala(Sa) and Aegiceras corniculatum(Ac) with different salinity levels(0‰, 5‰, 10‰, 15‰, 20‰, 30‰, 40‰ and 50‰) to explore the ecological, physiological and morphological adaptability of two mangrove species in response to salt stress. Ecological indexes included plant height, basal diameter, biomass, number of leaves, leaf length and width; and physiological indexes contained net photosynthesis rate, stomata conductance, transpiration rate and total chlorophyll; besides, paraffin method was used to observe morphological structure. Our result indicated:(1) Increasing of the salinity level could benefit to mangroves(≤30‰).(2) As the salinity level increased, the growing trend of physiological indexes such as net photosynthesis rate, stomata conductance and total chlorophyll first increased and then decreased.(3) The layers of palisade tissue increased when the salinity level at 15‰ and 20‰ for Sa, while it would be 0‰ and 5‰ for Ac. Therefore, Sa is suitable to be planted in artificial wetland as dominant specie and constructive specie, and Ac is a kind of companion specie for its low amount of height. Our results provide key information concerning the salt-tolerance mechanisms of mangrove plant and the construction of mangrove artificial wetland.更多还原