Schneider Larissa, Haberle Simon G, Maher William A, Krikowa Frank, Zawadzki Atun, Heijnis Henk
Department of Archaeology and Natural History, Australian National University, Fellows Rd, 2600, Canberra, ACT, Australia.
Department of Archaeology and Natural History, Australian National University, Fellows Rd, 2600, Canberra, ACT, Australia.
Chemosphere. 2016 Apr;148:369-79. doi: 10.1016/j.chemosphere.2015.12.086. Epub 2016 Jan 27.
Lake Kutubu, a large tropical lake in Papua New Guinea, is well known for its ecological importance; however, there have been recent changes to the pristine nature of this lake due to activities associated with the largest oil and gas project in PNG. The aim of this study was to determine the geochemical profile of sediment cores of Lake Kutubu and to comprehend the contamination changes undergone in this lake due to mining activities utilising the hydraulic fracturing method. Sediment core profiles of Na, Mg, Al, Si, P, Ca, Ti, Cr, Fe, Mn, Ni, Cu, Zn, As, Se, Sr, Cd, Ba, Ce, Pb and U, grain size and dating analyses were conducted for five sites in the lake. Grain size and dating demonstrated that the northwest side of Lake Kutubu has sediments of allocthonous origin while the southeast sediments are of autochthonous origin. Ba was the element with the largest changes in concentrations since 1990 and the best tracer of mining activities near the lake. Sites KTB 02 and KTB 10 northwest of the lake showed the most distinct changes in element concentrations. Element enrichment factors (EF = 2.8, 4.2 and 3.2 respectively) demonstrated that Mn, Se and Ba have undergone a moderate enrichment in the lake since mining activities started. Ni, Cd and Se concentrations exceed sediment guidelines in some samples. No guideline is available for Ba, and special attention should be given to this element in this lake. This study demonstrated that Lake Kutubu oil/gas extraction activities are significant sources of elements to this lake and highlights the need for studies on the partitioning and speciation of elements to understand organism metal exposure.
库图布湖是巴布亚新几内亚的一个大型热带湖泊，以其生态重要性而闻名；然而，由于与巴布亚新几内亚最大的石油和天然气项目相关的活动，该湖原始的自然状态最近发生了变化。本研究的目的是确定库图布湖沉积物岩芯的地球化学剖面，并了解该湖因采用水力压裂法的采矿活动而经历的污染变化。对该湖五个地点进行了钠、镁、铝、硅、磷、钙、钛、铬、铁、锰、镍、铜、锌、砷、硒、锶、镉、钡、铈、铅和铀的沉积物岩芯剖面、粒度和年代测定分析。粒度和年代测定表明，库图布湖的西北侧沉积物为异地成因，而东南侧沉积物为原地成因。钡是自1990年以来浓度变化最大的元素，也是该湖附近采矿活动的最佳示踪剂。湖西北的KTB 02和KTB 10地点元素浓度变化最为明显。元素富集因子（分别为EF = 2.8、4.2和3.2）表明，自采矿活动开始以来，锰、硒和钡在该湖经历了中度富集。一些样品中的镍、镉和硒浓度超过了沉积物指导标准。目前尚无钡的指导标准，对此湖中的该元素应给予特别关注。本研究表明，库图布湖的石油/天然气开采活动是该湖元素的重要来源，并强调需要对元素的分配和形态进行研究，以了解生物体的金属暴露情况。
