College of life Sciences, South-Central University for Nationalities, Wuhan, 430074, People's Republic of China.
Environ Sci Pollut Res Int. 2018 Jan;25(2):1773-1783. doi: 10.1007/s11356-017-0623-9. Epub 2017 Nov 4.
The response of periphyton biofilm and the submerged macrophyte tape grass (Vallisneria natans) to internal loading from eutrophic lake sediments were evaluated in microcosms. The sediments from the littoral zone and center of a lake were selected to carry out the microcosm experiment. To determine how the differences in the periphyton biofilm and V. natans growth alone or in combination, we measured changes in water quality, growth, and TP in the periphyton biofilm and V. natans in microcosms containing these sediments. The results showed that the average daily TN and TP removal rates were 32.6 and 35.4%, respectively, in the microcosms containing the lake center sediments by V. natans and the periphyton biofilm. The presence of the periphyton biofilm and V. natans increased the pH, dissolved oxygen, and redox potential and decreased the conductivity in the overlying water in all treatments. Compared to the state before the treatments, V. natans grew well, with a significant increase in biomass (3.1- to 5.5-fold growth) and TP amount (5.1- to 8.8-fold) in all treatments after 48 days. However, the growth of V. natans that combined with the periphyton biofilm was better than that of V. natans alone, as reflected by the dry weight, chlorophyll a content, malondialdehyde content, and TP amount. In conclusion, the periphyton biofilm was beneficial for the growth of V. natans, and the appropriate combination of V. natans and periphyton biofilm would be a potential method for the ecological restoration of eutrophic lakes.
在微宇宙中评估了富营养化湖泊沉积物内源负荷对周丛生物膜和沉水植物苦草（Vallisneria natans）的响应。选择了来自湖泊沿岸带和中心的沉积物进行微宇宙实验。为了确定周丛生物膜和 V. natans 单独或组合生长的差异，我们测量了微宇宙中含有这些沉积物的水质、周丛生物膜和 V. natans 的生长以及周丛生物膜中总磷（TP）的变化。结果表明，在含有湖心沉积物的微宇宙中，V. natans 和周丛生物膜的平均日 TN 和 TP 去除率分别为 32.6%和 35.4%。周丛生物膜和 V. natans 的存在增加了上覆水中的 pH 值、溶解氧和氧化还原电位，降低了电导率。与处理前相比，V. natans 在所有处理中生长良好，生物量（增长 3.1-5.5 倍）和 TP 含量（增长 5.1-8.8 倍）均显著增加，处理后 48 天。然而，与单独的 V. natans 相比，V. natans 与周丛生物膜结合后的生长更好，这反映在干重、叶绿素 a 含量、丙二醛含量和 TP 含量上。总之，周丛生物膜有利于 V. natans 的生长，V. natans 和周丛生物膜的适当组合可能是富营养化湖泊生态恢复的一种潜在方法。
