School of Environmental and Forest Sciences, University of Washington, Seattle, WA, United States of America.
Department of Earth and Space Sciences, University of Washington, Seattle, WA, United States of America.
Sci Total Environ. 2019 Nov 25;693:133404. doi: 10.1016/j.scitotenv.2019.07.210. Epub 2019 Jul 25.
Major and trace element deposition across western Washington, USA was assessed in 2016 and 2017 by analyzing tissue metal concentrations in the epiphytic mosses Isothecium stoloniferum (Bridel) and Kindbergia praelonga (Hedw.) Ochyra. We used an intensive, vertically stratified sampling approach in Acer macrophyllum canopies in the Hoh Rainforest on the Olympic Peninsula, WA and in Seattle, WA to collect 214 samples of I. stoloniferum. An extensive, ground-based sampling approach was used across an urban-to-wildland gradient to collect 59 K. praelonga samples. Intensive samples were collected four times (April, July, and October of 2016 and in January 2017) and extensive samples three times (April, July, and October 2016) to assess seasonal differences in metal concentrations across sampling locations. A total of 273 moss samples were analyzed for Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Sr, Ti, and Zn concentrations. Elevated concentrations of these elements were found in moss samples from both intensive and extensive sampling efforts across all seasons. Sampling location for both intensive and extensive sampling efforts was found to be a significant factor in determining moss metal concentrations. Metal deposition in and around Seattle appears to be derived from the regional transportation sector and other industrial sources. Ten I. stoloniferum samples from Seattle and the Hoh Rainforest were analyzed for Pb and Sr isotope ratios to help differentiate between natural and industrial-based emission sources. Hoh Rainforest Pb isotopes appear to be explained by a mixture of long-range Asian Pb influences and natural Pb sources, whereas Seattle Pb isotopes appear driven by industrial and road dust sources.
2016 年和 2017 年，通过分析附生苔藓 Isothecium stoloniferum（Bridel）和 Kindbergia praelonga（Hedw.）Ochyra 组织中的金属浓度，评估了美国华盛顿西部主要和痕量元素的沉积情况。我们在奥林匹克半岛华盛顿州的霍河雨林和西雅图的 Acer macrophyllum 树冠中使用密集的垂直分层采样方法收集了 214 个 I. stoloniferum 样本。我们使用广泛的基于地面的采样方法，在城市到荒地的梯度上收集了 59 个 K. praelonga 样本。密集样本采集了四次（2016 年 4 月、7 月和 10 月以及 2017 年 1 月），广泛样本采集了三次（2016 年 4 月、7 月和 10 月），以评估采样地点的金属浓度的季节性差异。共分析了 273 个苔藓样本的 Cd、Cr、Cu、Fe、K、Mg、Mn、Ni、Pb、Sr、Ti 和 Zn 浓度。在密集和广泛采样的所有季节，苔藓样本中都发现了这些元素的高浓度。采样地点是确定苔藓金属浓度的一个重要因素。西雅图及其周边地区的金属沉积似乎来自区域交通部门和其他工业来源。从西雅图和霍河雨林采集了 10 个 I. stoloniferum 样本，用于分析 Pb 和 Sr 同位素比值，以帮助区分自然和工业排放源。霍河雨林的 Pb 同位素似乎是由长程亚洲 Pb 影响和自然 Pb 源的混合解释的，而西雅图的 Pb 同位素则似乎是由工业和道路尘源驱动的。
