Differential effects of water depth and sediment type on clonal growth of the submersed macrophyte Vallisneria natans

作者：Xiao Keyan^*; Yu Dan; Wu Zhonghua

来源：Hydrobiologia, 2007, 589(1): 265-272.

DOI：10.1007/s10750-007-0740-4

• aquatic plant
• clonal growth
• morphological plasticity
• biomass allocation
• water depth
• sediment

The response of clonal growth and ramet morphology to water depth (from 60 to 260 cm) and sediment type (sand versus organic clay) was investigated for the stoloniferous submersed macrophyte Vallisneria natans in an outdoor pond experiment. Results showed that water depth significantly affected clonal growth of V. natans in terms of clone weight, number of ramets, number of generations, clonal radius and stolon length. V. natans showed an optimal clonal growth at water depths of 110-160 cm, but at greater depths clonal growth was severely retarded. A high allometric effect was exhibited in ramet morphology. Along the sequentially produced ramet generations, ramet weight and plant height decreased while stolon length and the root:leaf weight ratio increased. When using ramet generations as covariate, sediment type rather than water depth more strongly affected the ramet characteristics. For plants grown in clay, ramet weight, ramet height and stolon length were greater, and plants exhibited lower root:leaf weight ratio. These data suggest that water depth and sediment type have differential effects on clonal growth of V. natans: Water depth appears primarily to affect numerical increase in ramets and spatial spread, whereas sediment type mainly affects biomass accumulation and biomass allocation.

• 出版日期2007-9
• 单位武汉大学