Department of Bioresources and Rural System Engineering, Hankyong National University, Anseong, South Korea.
Department of Environmental and Safety Engineering, Ajou University, Suwon, South Korea.
Sci Rep. 2019 Oct 31;9(1):15754. doi: 10.1038/s41598-019-52393-1.
We investigated the influence of temperature on the capping efficiency to interrupt the release of nutrients from lake sediments. A 3-cm layer of Zeolite (ZL) or activated carbon (AC) was placed on the contaminated sediments, and nonwoven fabric mats (NWFM) were placed on top of these capping materials. Laboratory incubation experiments were performed under three different temperatures, namely 4, 15, and 30 °C. Under the uncapped condition at 30 °C, dissolved oxygen (DO) was depleted after 30 days, while at 4 °C and 15 °C, DO was present until the end of this experiment. DO concentration in overlying water was more dependent on the temperature than capping condition. ZL/NWFM effectively blocked the release of N from the sediments, and the capping efficiencies of ZL/NWFM for NH-N at 4, 15, and 30 °C were 98%, 96%, and 94%, respectively. For the interruption of P release, both ZL/NWFM and AC/NWFM were not effective at 4 and 15 °C. At 30 °C, however, AC/NWFM was effective, and its capping efficiencies at 30 °C for PO-P and T-P were 74.0% and 79.9%, respectively. In summary, nutrient release from sediments was accelerated at higher temperatures, and the effect of capping was significant at high temperature.
我们研究了温度对盖帽效率的影响，以阻止营养物质从湖泊沉积物中释放。在受污染的沉积物上放置 3 厘米厚的沸石（ZL）或活性炭（AC），并在这些盖帽材料上放置无纺土工布垫（NWFM）。在三种不同温度下进行了实验室孵育实验，分别为 4、15 和 30°C。在 30°C 未盖帽条件下，溶解氧（DO）在 30 天后耗尽，而在 4°C 和 15°C 下，DO 存在到实验结束。上覆水中的 DO 浓度比盖帽条件更依赖于温度。ZL/NWFM 有效地阻止了 N 从沉积物中的释放，ZL/NWFM 在 4、15 和 30°C 下对 NH-N 的盖帽效率分别为 98%、96%和 94%。对于 P 释放的中断，ZL/NWFM 和 AC/NWFM 在 4 和 15°C 时均无效。然而，在 30°C 时，AC/NWFM 是有效的，其在 30°C 时对 PO-P 和 T-P 的盖帽效率分别为 74.0%和 79.9%。总之，在较高温度下，沉积物中的营养物质释放会加速，而在高温下盖帽的效果更为显著。
