Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
Environ Sci Technol. 2010 Feb 1;44(3):985-91. doi: 10.1021/es903260y.
Laboratory experiments with sediments from three shallow Danish lakes were conducted to evaluate the effects of chemical lake restoration products during resuspension. Phosphorus (P) removal, sediment stability, sediment consolidation and color reduction were studied over time. The investigated products were aluminum (Al), Phoslock (a commercial bentonite product coated with lanthanum) and a combination of Al covered with bentonite (Al/Ben). All treatments effectively reduced the P concentration in the water. However, the treatments containing Al reduced the P concentration immediately after resuspension, whereas Phoslock required several days after resuspension to reduce the P concentration. Especially Phoslock, but also Al/Ben, increased the sediment stability threshold by 265% and 101%, respectively, whereas Al had no stabilizing effect. The fresh Al floc was resuspended 5x easier than untreated sediment. The largest consolidation of the sediment occurred with addition of Phoslock, followed by Al/Ben, while Al alone had no effect. Enhanced consolidation may be of importance for macrophyte colonisation of organic sediment. Phoslock improved the light climate moderately by removing color, whereas Al was very effective in removing color. Ben/Al showed intermediate effects on color reduction. These findings are important when decisions are made on restoration method for a specific lake, which may be more or less wind exposed.
实验室对丹麦三个浅水湖泊的沉积物进行了实验，以评估化学湖泊修复产品在再悬浮过程中的效果。研究了一段时间内的磷（P）去除、沉积物稳定性、沉积物固结和颜色减少。研究的产品有铝（Al）、Phoslock（一种涂有镧的商业膨润土产品）和 Al 覆盖膨润土的组合（Al/Ben）。所有处理都有效地降低了水中的 P 浓度。然而，含 Al 的处理在再悬浮后立即降低了 P 浓度，而 Phoslock 需要再悬浮几天后才能降低 P 浓度。特别是 Phoslock，但也包括 Al/Ben，分别将沉积物稳定性阈值提高了 265%和 101%，而 Al 则没有稳定作用。新鲜的 Al 絮体比未处理的沉积物更容易再悬浮 5 倍。添加 Phoslock 后，沉积物的固结作用最大，其次是 Al/Ben，而单独添加 Al 则没有效果。增强的固结作用对于有机沉积物中大型植物的定殖可能很重要。Phoslock 通过去除颜色适度改善了光照条件，而 Al 在去除颜色方面非常有效。BEN/Al 对颜色减少的影响介于两者之间。在为特定湖泊做出修复方法决策时，这些发现很重要，因为湖泊可能更容易或更不容易受到风的影响。
