Kang Li, Haasler Sina, Mucci Maíra, Korving Leon, Dugulan Achim Iulian, Prot Thomas, Waajen Guido, Lürling Miquel
Aquatic Ecology & Water Quality Management Group, Department of Environmental Sciences, Wageningen University, P.O. Box 47, 6700 AA, Wageningen, The Netherlands.
Freshwater Ecology Group, Department of Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark.
Water Res. 2023 Oct 1;244:120391. doi: 10.1016/j.watres.2023.120391. Epub 2023 Jul 23.
The eutrophic Bouvigne pond (Breda, The Netherlands) regularly suffers from cyanobacterial blooms. To improve the water quality, the external nutrient loading and the nutrient release from the pond sediment have to be reduced. An enclosure experiment was performed in the pond between March 9 and July 29, 2020 to compare the efficiency of dredging, addition of the lanthanum-modified bentonite clay Phoslock® (LMB), the aluminum-modified zeolite Aqual-P™ (AMZ) and FeCl to mitigate nutrient release from the sediment. The treatments improved water quality. Mean total phosphorus (TP) concentrations in water were 0.091, 0.058, 0.032, 0.031, and 0.030 mg P L in controls, dredged, FeCl, LMB and AMZ treated enclosures, respectively. Mean filterable P (FP) concentrations were 0.056, 0.010, 0.009, 0.005, and 0.005 mg P L in controls, dredged, FeCl, LMB and AMZ treatments, respectively. Total nitrogen (TN) and dissolved inorganic nitrogen (DIN) were similar among treatments; lanthanum was elevated in LMB treatments, Fe and Cl in FeCl treatments, and Al and Cl in AMZ treatments. After 112 days, sediment was collected from each enclosure, and subsequent sequential P extraction revealed that the mobile P pool in the sediments had reduced by 71.4%, 60.2%, 38%, and 5.2% in dredged, AMZ, LMB, and FeCl treatments compared to the controls. A sediment core incubation laboratory experiment done simultaneously with the enclosure experiment revealed that FP fluxes were positive in controls and cores from the dredged area, while negative in LMB, AMZ and FeCl treated cores. Dissolved inorganic nitrogen (DIN) release rate in LMB treated cores was 3.6 times higher than in controls. Overall, the applied in-lake treatments improved water quality in the enclosures. Based on this study, from effectiveness, application, stakeholders engagement, costs and environmental safety, LMB treatment would be the preferred option to reduce the internal nutrient loading of the Bouvigne pond, but additional arguments also have to be considered when preparing a restoration.
富营养化的布维涅池塘（荷兰布雷达）经常遭受蓝藻水华的困扰。为了改善水质，必须减少外部营养物质负荷以及池塘沉积物中的营养物质释放。2020年3月9日至7月29日在该池塘进行了围隔实验，以比较疏浚、添加镧改性膨润土Phoslock®（LMB）、铝改性沸石Aqual-P™（AMZ）和FeCl减轻沉积物中营养物质释放的效果。这些处理改善了水质。对照、疏浚、FeCl、LMB和AMZ处理围隔中水体的平均总磷（TP）浓度分别为0.091、0.058、0.032、0.031和0.030mg P/L。对照、疏浚、FeCl、LMB和AMZ处理中可过滤磷（FP）的平均浓度分别为0.056、0.010、0.009、0.005和0.005mg P/L。各处理之间总氮（TN）和溶解无机氮（DIN）相似；LMB处理中镧含量升高，FeCl处理中Fe和Cl含量升高，AMZ处理中Al和Cl含量升高。112天后，从每个围隔中采集沉积物，随后的连续磷提取显示，与对照相比，疏浚、AMZ、LMB和FeCl处理中沉积物中的可移动磷库分别减少了71.4%、60.2%、38%和5.2%。与围隔实验同时进行的沉积物柱培养实验室实验表明，对照和疏浚区域的柱中FP通量为正，而LMB、AMZ和FeCl处理的柱中为负。LMB处理的柱中溶解无机氮（DIN）释放速率比对照高3.6倍。总体而言，所应用的湖泊处理改善了围隔中的水质。基于这项研究，从有效性、应用、利益相关者参与、成本和环境安全方面考虑，LMB处理将是减少布维涅池塘内部营养物质负荷的首选方案，但在准备修复时还必须考虑其他因素。
