Nutrients supplied by sediment of lakes and light are likely important factors determining the growth balance between Leptolyngbya sp. biofilm and Vallisneria natans. Therefore, experiments with varying light are conducted to compare the effect of nutrient release from surface sediment on their growth. The results show that changes in pH, dissolved oxygen (DO) and redox potential (Eh) are significantly correlated with the changes in nitrogen(N) and phosphorus (P) concentrations in the water (p < 0.05). The optimum light intensity for the growth of Leptolyngbya sp. and V. natans is different. The biomass of Leptolyngbya sp. biofilm is higher at 2–27 µmol m⁻²·s⁻¹, but the biomass of V. natans is positively correlated with light intensity (2–54 µmol m⁻²·s⁻¹) (p < 0.05). The Leptolyngbya sp. biofilm and V. natans can retain P from sediment and significantly remove N in the overlying water. The total P amounts retained by V. natans are significantly higher than that of Leptolyngbya sp. biofilm in all treatments, and the potential for P retention of V. natans increases with the increase of light intensity. The retention of P amounts in the Leptolyngbya sp. biofilm mainly formed 47.8% Fe-bound P, but 57% NH₄CI-bound P in the V. natans.

中文翻译：

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Leptolyngbya sp. 的作用。生物膜和苦草生长对沉积物营养释放的影响

湖泊沉积物和光提供的养分可能是决定Leptolyngbya sp.之间生长平衡的重要因素。生物膜和苦草。因此，进行了不同光照的实验，以比较表层沉积物释放养分对其生长的影响。结果表明，pH、溶解氧（DO）和氧化还原电位（Eh）的变化与水中氮（N）和磷（P）浓度的变化显着相关（p < 0.05）。Leptolyngbya sp.生长的最佳光照强度。而V. natans则不同。Leptolyngbya sp. 的生物量。生物膜在 2–27 µmol m ^-2 ·s ^{-1 时}更高，但V. natans的生物量与光强度呈正相关（2-54 µmol m ^-2 ·s ^-1）（p < 0.05）。该Leptolyngbya SP。生物膜和V. natans可以保留沉积物中的 P 并显着去除上覆水中的 N。V. natans保留的总磷量显着高于 Leptolyngbya sp。生物膜在所有处理中，并且V. natans保留磷的潜力随着光强度的增加而增加。Leptolyngbya sp中 P 的保留量。生物膜主要形成 47.8% 的 Fe 结合 P，但 57% NH ₄ CI 结合 P 在V. natans。