中国岩黄耆属(Hedysarum L.)植物区系生态地理分布

依据种的现代分布、替代关系、地质历史、古气候和化石资料,探讨了中国岩黄耆属植物区系的发生、演变及形成机制.结果表明:岩黄耆属可能是由古地中海旱生植物区系中一类中生的原始灌木类群,在晚始新世到早渐新世或比这个时期稍晚一些,经过第三纪以来的环境分异变化,逐渐形成适应高寒山地生长的扁荚组种类和适应干旱环境生长的多茎组、短茎组种类,短茎组种类是多茎组对干旱强化进一步适应的结果,与此同时,原始的灌木类群自身也在继续演化,形成适应荒漠半荒漠生长的种类.这种演化过程揭示出生存环境中水热条件的剧烈变化是植物演化的主要动力.

Floristic Eco-geographical Distribution of Hedysarum L. in China

The floristic origin,differentiation and mechanism of formation of Hedysarum L.distributed in China were discussed based on the present distribution patterns,vicarism of species,together with historical geology,paleoclimate and available fossil records in this paper.Our results support the opinion that mesial ancestral shrub taxa in the flora of arid Old Mediterranean have been evolving into the Sect.obscura adapted to freezing environment,as well as Sect.acaulia,Sect.fruticosum and Sect.acaulia adapted to arid environment.Sect.acaulia probably originated from Sect.subacaulia for further arid intensification through the environmental differentiation of the Tertiary since the Late Eocene to Early Oligocene,even later than the period.The evolutionary process as above revealed that main drive force of plant evolution lies in water and heat variation in the environment existed.