关键词: 浮游植物, 赤潮, 丰度, 水动力, 长江口

Abstract: We measured total nitrogen (N) and total phosphorus (P) concentrations in leaves of Leymus chinensis, Phragmites communis and  Lespedeza hedysaroides in Songnen Plain meadow, and analyzed their relationship with soil total N and total P concentrations. The results showed that foliar total N concentration differed significantly among three species (P<0.05), while foliar total P concentrations did not show significant difference (P>0.05). The leaf N concentration of the three species had no significant correlation with soil total N concentrations (P>0.05), while the leaf N:P ratio was significantly negatively correlated with soil total P concentrations (P<0.05), suggesting that in our study area, different plant species had great difference in their leaf N concentration, but less difference in their leaf P concentration. Compared with leaf N and P concentrations, leaf N:P ratio was more related to soil N and P concentrations. In addition, the growth of Leymus chinensis and Lespedeza hedysaroides in study area was P-limited, and thereby, appropriate application of P fertilizer could be considered.

Key words: Phytoplankton, Red tide, Abundance, Water dynamics, Changjiang River estuary