水位梯度对三江平原典型湿地植物根茎萌发及生长的影响

通过水位控制模拟试验,研究了水位梯度对三江平原典型湿地植物——小叶章和毛苔草根茎萌发及生长的影响.结果表明:2种植物对水位的适应策略各异,小叶章种群密度、平均高度和最大高度都在0cm水位条件下出现极大值,而毛苔草种群平均高度和最大高度随水位上升而升高,种群密度则随水位上升而下降.在萌发初期,一定时间的无淹水环境促进2种湿地植物的根茎萌发,而淹水抑制其萌发;在生长期,过度的淹水限制了小叶章的生长,而毛苔草则水分越多生长越旺盛;干旱缺水限制植物生长,可能会引起植物生活史的改变.

Effects of water level on the rhizomatic germination and growth of typical wetland plants in Sanjiang Plain

With simulation test,this paper studied the effects of water level on the rhizomatic germination and growth of Calamagrostis angustifolia and Carex lasiocarpa,the two typical wetland plants in Sanjiang Plain.The results showed that these two plants had different responses to water level.The population density,mean height,and maximum height of C.angustifolia reached the peak at 0 cm water level;while the mean and maximum height of C.lasiocarpa increased,but its population density decreased with increasing water level.At the early stage of germination,definite duration without inundation promoted the rhizomatic germination of these two plants,while continuous inundation constrained it.During growth period,excess inundation limited the growth of C.angustifolia,but C.lasiocarpa grew better under deeper water.Drought constrained the growth of C.angustifolia and C.lasiocarpa,and possibly,changed their life history.