Abstract

Natarajan P, Gulliver JS, Arnold WA. 2021. Iron filings application to reduce lake sediment phosphorus release. Lake Reserv Manage. 27:143–159.

Surface water impairments due to excess phosphorus loading from the watershed and internal recycling from sediments have been reported worldwide. This study investigated the application of iron metal filings to lake sediments as a method to control sediment phosphorus release. Using batch studies, a zero-valent iron filings material was selected for laboratory dosing experiments with lake sediment cores. Iron filings doses of 0 (control), 0.01, 0.1, and 1 g/cm² were added to sediment cores collected from a eutrophic lake in Minnesota, United States, to determine the impacts of iron addition on the oxic and anoxic phosphate (PO₄-P) flux at 20 C and 10 C in the laboratory. Under oxic conditions, PO₄-P release did not occur from the sediments, and low water column PO₄-P concentrations were maintained in the iron-dosed and control cores. After switching to anoxic conditions, the 0.1 and 1 g/cm² iron doses continued to reduce or fully prevent sediment PO₄-P flux. The enhanced supply of iron in the sediments was found to reduce the porewater PO₄-P, resulting in no apparent PO₄-P diffusion across the sediment–water interface and low PO₄-P in the overlying water under oxic and anoxic conditions. Further evaluation using in situ experiments is needed to assess the effectiveness of iron filings addition in sequestering sediment phosphorus under natural conditions.

摘要

Natarajan P，Gulliver JS，阿诺德（华盛顿州）。2021.减少铁屑沉积以减少湖泊沉积物中磷的释放。湖后备管理。27：143–159。

在世界范围内，已经报道了由于流域过多的磷负载和沉积物内部循环而造成的地表水损害。这项研究调查了铁金属屑在湖泊沉积物中的应用，以此作为控制沉积物磷释放的一种方法。使用批处理研究，选择了零价铁屑材料用于湖沉积物芯的实验室配料实验。将铁屑剂量为0（对照），0.01、0.1和1 g / cm ^2的铁屑添加到从美国明尼苏达州的富营养化湖泊中收集的沉积岩心中，以确定铁添加对含氧和缺氧磷酸盐（PO）的影响在实验室中于20 C和10 C时产生_4- P）通量。在有氧条件下，PO ₄-P不会从沉积物中释放出来，在铁剂和对照岩心中都保持了低水柱中的PO ₄ -P浓度。切换到缺氧条件后，铁剂量为0.1 g / cm ²和1 g / cm ²继续减少或完全防止沉积物PO ₄ -P通量。发现沉积物中铁的​​供应增加会减少孔隙水PO ₄ -P，从而导致在沉积物-水界面上没有明显的PO ₄ -P扩散，并且在有氧和无氧条件下上覆水中的PO ₄ -P较低。需要使用原位实验进行进一步评估，以评估铁屑添加在自然条件下螯合沉积物磷的有效性。