宁夏贺兰山自然保护区蒙古扁桃群落物种多样性

Species diversity of Prunus mongolica community in Ningxia Helan Mountain Nature Reserve

通过野外实地调查40个蒙古扁桃样地,得到野生维管束植物133种（包括种下等级）,隶属于91属39科。区系分析表明,宁夏贺兰山自然保护区蒙古扁桃群落具有温带性质,且以北温带成分优势,占总属数的35.16%。生活型谱中地面芽植物占总种数的近半,表明蒙古扁桃群落生境寒冷而干旱。物种多样性指数测度结果表明：1）草本层的多样性高于灌木层;2）北段海拔1700-1800 m处多样性最高,则在中段2000-2100 m处多样性最高;3）北段阴坡的多样性最低,中段则相反,阴坡和半阴坡的多样性比阳坡和半阳坡的高;4）坡度20°以下坡上的群落多样性高于20°以上坡的多样性,且20°以上的坡,随坡度增加而多样性减少。

According to the field survey of Prunus mongolica community, there are 133 vascular plant species （including subspecies）, belonging to 91 genura and 39 families. The result of flora analysis showed that Prunus mongolica community in Ningxia Helan Mountain Nature Reserve has characteristics of temperate, and North Temperate component is dominant, accounting for 35.16 %. Hemicryptophytes accounts for almost 50 % in total species among the life form, it indicates that habitat of Prunus mongolica community is cold and dry. The results of measuring species diversity indices show ： 1 ） The species diversity of herbage layer is higher than shrub layer; 2） The species diversity is the highest in 1700 - 1800m of north part, the species diversity is the highest in 2000 -2100m of middle area; 3） The species diversity is the lowest in shady slope of north area, in converse, the species diversity of shady slope and half shady slope is higher than tailo and half tailo of middle area; 4） The species of the slope of less than 20°is higher than the slope of more than 20°, and the species diversity of the slope of more than 20° decreases while the slope increasing.