濒危植物狭果秤锤树所在群落的区系特征

调查重新发现了濒危植物狭果秤锤树(Sinojackia rehderiana)在赣北的分布,采用植被调查样方法研究了狭果秤锤树所在群落维管植物的区系特征.结果表明,该区系组成复杂,物种密度相对较高.在1 600 m2样方中,有维管束植物57科74属79种,其中蕨类植物6科10属10种,双子叶植物43科53属58种,单子叶植物8科11属11种.物种密度约达5种.(100 m2)-1.分布区类型多样,热带区系成分占优势.科、属、种地理成分以热带分布成分为主,温带成分占有一定比例;反映了该群落的热带-亚热带区系性质.热带成分与温带成分在本区交汇,体现出中亚热带向北亚热带植物区系过渡的特征.该群落分布面积小且邻近村落,具有明显的生态脆弱性,禁伐是维持该森林群落稳定性的关键措施.

Floristic characteristics of a community with endangered plant Sinojackia rehderiana in the north of Jiangxi

Through survey,distribution of rare and endangered plant Sinojackia rehderiana was rediscovered in north Jiangxi Province.In this article,the floristic composition of vascular plants of family,genera and species in the communities with S.rehderiana,areal types and the floristic characteristics were studied by using the quadrat method for vegetation survey.The results showed that the floristic composition was complicated and species has a higher density: there are 57 families,74 genera and 79 species of vascular plants in an area of 1 600 m2 of communities with S.rehderiana,including 6 families,10 genera and 10 species of fern,43 families,53 genera and 58 species of dicotyledon,8 families,11 genera and 11 species of monocotyledon.The species density was about 5 ·(100 m2)-1 in the communities.The flora was dominated of Tropical floristic elements,connected nearby floristic areas extensively and diverse areal types.The areal types of families,genera and species were mainly tropic elements and with a certain proportion of temperate elements,which showed the tropic-subtropical floristic nature of the communities.Tropical elements and temperate elements were intersected in the district,therefore,which was to reflect the floristic characteristics of the transition from central subtropics to north subtropics.This community is small area and adjoining villages,so the ecological frangibility there is evident.The key point to keep the stability of this community is to prohibit felling.