长期刈割及围栏封育方式对大油芒种群构件特征的影响

Effects of Long-term Mowing and Enclosure on Module Traits of Spodiopogon sibiricus Population

对松嫩平原长期刈割和围栏封育利用方式下的大油芒(Spodiopogon sibiricus)种群构件特征进行了研究,结果表明,2种利用方式下,大油芒种群分株由2~3个龄级构成,根茎由3~4个龄级构成,均呈增长型年龄结构。长期刈割方式下,潜在种群由苗和芽组成,而围栏封育方式下仅存在芽构件。在2种利用方式下,分株生产力、根茎贮藏力、分株和根茎的营养繁殖力均以年轻龄级最高。相对于围栏封育方式,长期刈割促进了苗的输出,增加了根茎营养繁殖力,但整体上使大油芒种群分株数量和生物量、根茎长度和生物量、分株生产力和总芽数显著降低。因此,长期刈割对大油芒种群的维持和更新产生不利影响。

Module traits were compared under long-term mowing and enclosure utilization of Spodiopogon sibiricus population in Songnen Plain of China.The results showed that ramets of S.sibiricus consisted of 2 to 3 ages and rhizomes consisted of 3 to 4 ages in two utilization types,which were both increasing age structure.Under long-term mowing,potential population consisted of juvenile tillers and buds,but only buds in enclosure utilization.Productivity of ramets,storage ability of rhizomes and vegetative propagation capacity of ramets and rhizomes were the greatest at 1 st age.Relative to the enclosure utilization,longterm mowing promoted the output of juvenile tillers and vegetation propagation capacity of ramets,but on the whole,it significantly decreased ramets number and biomass,root length and biomass,productivity of ramets and total buds.This research concluded that long-term mowing utilization has negative effect on maintenance and regeneration of S.sibiricus population.