Department of Geology and Geophysics, Texas A&M University, College Station, TX 77843, USA.
J Environ Qual. 2010 Feb 19;39(2):568-79. doi: 10.2134/jeq2009.0270. Print 2010 Mar-Apr.
The accumulation of polycyclic aromatic hydrocarbons (PAH) in soil, plants, and water may impart negative effects on ecosystem and human health. We quantified the concentration and distribution of 41 PAH (n = 32), organic C, total N, and S (n = 140) and investigated PAH sources using a chronosequence of floodplain soils under a natural vegetation succession. Soil samples were collected between 0- and 260-cm depth in bare land (the control), wetland, forest, and grassland areas near a closed municipal landfill and an active asphalt plant (the contaminant sources) in the north bank of the Canadian River near Norman, OK. Principal component, cluster, and correlation analyses were used to investigate the spatial distribution of PAH, in combination with diagnostic ratios to distinguish pyrogenic vs. petrogenic PAH suites. Total PAH concentration (SigmaPAH) had a mean of 1300 ng g(-1), minimum of 16 ng g(-1), and maximum of 12,000 ng g(-1). At 0- to 20-cm depth, SigmaPAH was 3500 +/- 1600 ng g(-1) (mean +/- 1 SE) near the contaminant sources. The most common compounds were nonalkylated, high molecular weight PAH of pyrogenic origin, i.e., fluoranthene (17%), pyrene (14%), phenanthrene (9%), benzo(b)fluoranthene (7%), chrysene (6%), and benzo(a)anthracene (5%). SigmaPAH in the control (130 +/- 23 ng g(-1)) was comparable to reported concentrations for the rural Great Plains. Perylene had a unique distribution pattern suggesting biological inputs. The main PAH contamination mechanisms were likely atmospheric deposition due to asphalt production at the 0- to 20-cm depth and past landfill operations at deeper depths.
多环芳烃 (PAH) 在土壤、植物和水中的积累可能会对生态系统和人类健康产生负面影响。我们量化了 41 种 PAH（n = 32）、有机碳、总氮和硫（n = 140）的浓度和分布，并通过天然植被演替下的洪泛区土壤的时间序列研究了 PAH 的来源。在俄克拉荷马州诺曼市附近加拿大河北岸的一个关闭的市政垃圾填埋场和一个活跃的沥青厂附近的裸地（对照）、湿地、森林和草地地区，从 0 到 260 厘米深度采集土壤样本。主成分、聚类和相关分析用于研究 PAH 的空间分布，结合诊断比来区分源自热解和源自石化的 PAH 系列。总 PAH 浓度（SigmaPAH）的平均值为 1300ng/g，最小值为 16ng/g，最大值为 12000ng/g。在 0 到 20 厘米的深度，在污染源附近，SigmaPAH 为 3500 ± 1600ng/g。最常见的化合物是非烷基化的、源自热解的高分子量 PAH，即荧蒽（17%）、芘（14%）、菲（9%）、苯并（b）荧蒽（7%）、屈（6%）和苯并（a）蒽（5%）。对照区（130 ± 23ng/g）的 SigmaPAH 与大平原农村地区报告的浓度相当。培利烯具有独特的分布模式，表明存在生物输入。主要的 PAH 污染机制可能是由于在 0 到 20 厘米的深度进行沥青生产以及在更深的深度进行过去的垃圾填埋作业而导致的大气沉积。
