大兴安岭南部山地苔藓植物区系多样性研究

于2009～2012年对大兴安岭南部山地6个自然保护区的苔藓植物进行了野外实地调查,对所采集的1 800余号标本进行室内分析鉴定,并计算分析其种类组成、区系地理成分、地区之间相似性系数和相异系数的欧氏距离比较,及其8种生境中苔藓植物多样性指数、丰富度指数、均匀度指数和优势度指数等,为保护区的管理和建设提供基础资料。结果表明:(1)大兴安岭南部山地6个自然保护区共有苔藓植物48科,134属,330种,其中苔类16科,21属,38种,1变种;藓类32科,113属,274种,14变种,2变型,1亚种。(2)首次发现中国新记录4种:长柄紫萼藓(Grimmia longirostris Hook.),毛尖连轴藓[Schistidium lancifolium(Kindb.)Blom.],平叶真藓(Bryumlaevifilum Syed.),凹叶毛灰藓[Homomallium adnatum(Hedw.)Broth.],首次发现本地区新记录12种。(3)以丛藓科为代表的旱生藓类在本区占有优势地位;区系地理成分以温带成分(60.79%)和东亚成分(16.19%)为主。(4)大兴安岭南部山地与兴安北部和燕山北部山地亲缘关系较近;生境条件的变化对苔藓植物多样性产生了一定的影响,湿润土生和石生生境为本区苔藓植物最丰富的生境,水生生境中苔藓植物分布最少。研究发现,大兴安岭南部山地苔藓植物区系是连接华北区、东北区、蒙新区和阴山地区的过渡性地带;与燕山北部和兴安北部相比,大兴安岭南部山地大面积苔藓植物地被层分布较少的主要原因是森林密度和湿度较低。因此,建立保护区对保护大兴安岭南部山地脆弱的森林、草原过渡生态系统,保护中国野生动植物类群及其他珍稀动植物的繁衍均具有十分重要的意义。

Bryophytes Diversity and Flora in the Southern Greater Khingan Mountains

Bryological field investigations were carried out in the 6 nature reserves of Southern Greater Khingan Mountains during 2009~2012.We collected and identified approximately 1 800 specimens,then calculated and analyzed bryological composition and floristic characteristics of this area;similarity coefficient and euclidean distance of 10 mountains;the diversity index,the species richness,the evenness index and dominance index of 8 kinds of habitat.Our objectives were to provide basic data for construction and management of nature reserve.The results showed that:(1)There were a total of 330 species (including 15 varieties,2 forms and 1 subspecies) of bryophytes belonging to 134 genera and 48 families,among which there were 38 species and 1 varieties of liverworts belonging to 21 genera and 16 families and 274 species,14 varieties,2 forms and 1 subspecies of mosses belonging to 113 genera and 32 families in the 6 nature reserves of Southern Greater Khingan Mountains.(2)Reported 4 species new records of China (Grimmia longirostris Hook.,Schistidium lancifolium (Kindb.) Blom.,Bryum laevifilum Syed.,Homomallium adnatum (Hedw.) Broth.and 12 species new to this area.(3)Dominant families (e.g.Pottiaceae) in this area are adapted to arid habitats.The statistical analysis of the flora elements indicates that it has an absolutely dominant majority of north temperate elements and a proportion of East Asian elements,numbering 60.79% and 16.19%.(4)The region had the highest similarity with Northern Yanshan Mountains and Northern Greater Khingan Mountains;changes of the habitat conditions have certain effect on bryophytes diversity,which is the highest in wet soil habitat and wet rock habitat,the lowest in aquatic habitat.The study reflects that the bryoflora of Southern Greater Khingan Mountains is a transitional zone connecting North China region,North-Eastern China region,Inner Mongolia-Xinjiang region and Yinshan area;compared with Northern Yanshan Mountains and Northern Greater Khingan Mountains,forest density and humidity caused less distribution of the ground vegetation of this area.We suggest that nature reserve should be established in this area to protect transitional ecosystem of forest and grassland,establishing nature reserve also plays an important role in protecting wildlife groups and reproduction of rare and endangered species.