摘要
米氏冰草(Agropyron michnoi)是根茎型无性系植物。为了解米氏冰草在沙地生境中的繁殖适应机制,采取单位面积挖掘取样,对呼伦贝尔沙地不同演替阶段的米氏冰草分蘖株和根茎年龄结构进行了调查。结果表明:生长季末期与前期比较,米氏冰草分蘖株数量在流动和半固定沙地均增长了1.5倍,固定沙地无变化;而根茎长度在流动、半固定和固定沙地分别增加5.0,2.1和2.0倍。米氏冰草无性系分蘖株由4个龄级组成,分蘖株数量的年龄结构,在流动沙地均为明显增长型;半固定沙地由增长型转变成稳定型;固定沙地为稳定型。根茎在流动沙地由3个龄级组成,在半固定和固定沙地由4个龄级组成。随着生长季的进程,根茎长度的年龄结构,在流动沙地、半固定沙地和固定沙地均由稳定型变成增长型,增长趋势从大到小排序为:流动沙地>半固定沙地>固定沙地。随着植物群落的次生演替进程,米氏冰草无性系构件的年龄结构呈由增长型向稳定型过渡的趋势。
Agropyron michnoi samples were collected from three different ecological successions to investigate the structures of tillers and rhizomes regarding their propagating mechanism.Results show that the number of tillers growing in shifting sand land and half-stabilized sand land were increased 1.5 times at the end of growing season more than at the early season,whereas there is no change in stabilized sandy land.Meanwhile,rhizome length increased 2.7 times,1.3 times and 1.4 times in each land type,respectively.The developing tillers were classified as 4 age-ranks.The age structures of tillers displayed an expansive type in shifting sand land,expansive-stable type in half stabilized sand land and a stable type in stabilized sand land.The rhizomes contained 3 age-ranks in shifting sand land and 4 age-ranks in half stabilized and stabilized sand land.The age structure types of rhizome lengths in Agropyron michnoi were shifting to expansive types from stable types in half stabilized and stabilized sandy land with growing season going.The increasing trends of rhizome lengths were ranked as: sandy landhalf stabilizedstabilized sand land.The general trend of age structure for the clonal module of Agropyron michnoi was a shift to stable types from expansive types when the succession of land types shifted to stable sandy land from sandy land.
出处
《草地学报》
CAS
CSCD
北大核心
2011年第3期367-371,387,共6页
Acta Agrestia Sinica
基金
国家"十一五"科技支撑计划项目(2006BAD26B04-03)
内蒙古自治区自然科学基金项目(2010MS0509)资助
关键词
米氏冰草
分蘖株
根茎长度
年龄结构
Agropyron michnoi
Tiller
Length of rhizome
Age structure