Growth and morphological responses to water level and nutrient supply in three emergent macrophyte species
Growth and morphological responses to water level and nutrient supply in three emergent macrophyte species
复制标题
三种挺水植物物种的生长和形态对水位和养分供应的响应
DOI：
10.1007/s10750-008-9689-1
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发表时间：
2009-05-01
期刊：
影响因子：
2.6
通讯作者：
Xie, Yonghong
中科院分区：
文献类型：
--
作者：
Luo, Wenbo;Xie, Yonghong
三江平原是中国最大的淡水沼泽，植物沿水位梯度分布的现象十分普遍。该实验的目的是确定水位和养分有效性对平原植物分区的作用。通过在两个水位（相对于土壤表面 0.1 和 10.0 厘米）和两个养分供应水平（每个容器 0 和 0.5 克缓释肥料）下生长，研究了三种多年生挺水大型植物的生长和根系形态。在平原地区，毛果苔草通常出现在低海拔地区，Glyceria spiculosa 则出现在中海拔地区，而Deyeuxia angustifolia 则出现在高海拔地区。 10.0 cm水位下相对生长率以毛果最大，狭叶相对生长率最低。 3个物种中，只有狭叶总生物量受水位影响，且随水位升高而降低。高营养供应导致 C. lasiocarpa 和 G. spiculosa 的总生物量增加。高水位导致 G. spiculosa 的根直径增加，而 C. lasiocarpa 的根长度减少。在10.0厘米的水位中，低养分供应导致小叶兰的根变细，但导致毛果花的比根长度（SRL）增加和刺花的根直径增加。仅在 G. spiculosa 中观察到水位对根部孔隙度的影响，并且养分改良并未影响所有物种的根部孔隙度。这些数据表明，养分和水位都是调节三江平原植物分布格局的重要因素，因为毛果藤和毛蓼对养分供应相对敏感，而狭叶石竹对水位敏感。
Sanjiang Plain is the largest freshwater marsh in China, where plant zonation along water-level gradients is a common phenomenon. The aim of this experiment was to identify the role of water level and nutrient availability on plant zonation in the plain. Growth and root morphology of three perennial emergent macrophyte species were investigated by growing in two water levels (0.1 and 10.0 cm, relative to soil surface) and in two levels of nutrient supply (0 and 0.5 g slow-release fertilizer per container). In the plain, Carex lasiocarpa typically occurs at low elevations, Glyceria spiculosa at medial elevations, and Deyeuxia angustifolia at high elevations. The relative growth rate was the highest in C. lasiocarpa and the lowest in D. angustifolia in the 10.0-cm water level. Among the three species, only total biomass of D. angustifolia was affected by water level, and decreased with increasing water level. High nutrient supply led to increased total biomass in C. lasiocarpa and G. spiculosa. High water level led to an increased root diameter in G. spiculosa and a decreased root length in C. lasiocarpa. In the 10.0-cm water level, low nutrient supply led to thinner roots in D. angustifolia, but resulted in an increased specific root length (SRL) in C. lasiocarpa and root diameter in G. spiculosa. Water-level effect on root porosity was only observed in G. spiculosa, and nutrient amendment did not influence root porosity in all the species. These data indicate that both nutrient and water level are important factors regulating plant distribution pattern in the Sanjiang Plain, because both C. lasiocarpa and G. spiculosa are relatively sensitive to nutrient supply whereas D. angustifolia is sensitive to water level.