Luo Dong-Xia, Zhang Shu-Juan, Yang Rui-Qiang
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
School of Environment, Tsinghua University, Beijing 100084, China.
Huan Jing Ke Xue. 2016 Jul 8;37(7):2745-2755. doi: 10.13227/j.hjkx.2016.07.043.
Soils were collected from Shergyla Mountain shade slope and south-facing slope in southeast Tibetan Plateau (TP) in August 2012 and they were measured for polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs)(including HCHs and DDTs). The concentrations of ∑PAHs ranged from 99.3 to 1984 ng·g dw, with a mean value of 1017 ng·g dw. HCHs and DDTs in soils samples were in the range of 0.37-2.07 ng·g dw (mean 1.15 ng·g dw) and 0.70-43.9 ng·g dw (mean 9.87 ng·g dw), respectively. The concentrations of all measured compounds were much higher than those in central or western TP,and the PAHs concentration was even up to two orders of magnitude. The concentrations of -HCH and DDTs in south-facing slope increased with altitude, but HCHs and DDTs in shade slope had no significant correlation with altitude. There was no consistent increasing or decreasing trend of PAHs in shade slope with altitude, and the concentrations of PAHs in south-facing slope showed a higher value in lower altitude, indicating the existence of local pollution emissions. The PAHs profile was dominated by lighter constituents (2 & 3-ring accounted for higher than 85%),inferring that the PAHs in the study area were largely influenced by long range atmospheric transport (LRAT) of pollutants. The special diagnostic ratios of PAHs suggested that PAHs were mainly produced by low temperature combustion of biomass and fossil fuels, except that two sampling sites of shade slope had been possibly influenced by oil residue. The relatively low ratios of /-HCH inferred HCHs in the research area was the result of the combined contribution of the historical technical HCHs and Lindan. The ratios of '-DDE/'-DDT and '-DDT/'-DDT indicated DDTs were from the combined contribution of the historical technical DDTs and dicofol. According to the profile of PAHs, HCHs and DDTs and the meteorological conditions of Shergyla Mountain, the transport of PAHs and OCPs in the study area was mainly influenced by the Indian Monsoon.
2012年8月，从青藏高原东南部的色季拉山阴坡和阳坡采集土壤样本，测定其中的多环芳烃（PAHs）和有机氯农药（OCPs，包括六氯环己烷和滴滴涕）含量。∑PAHs浓度范围为99.3至1984 ng·g干重，平均值为1017 ng·g干重。土壤样本中六氯环己烷和滴滴涕含量分别在0.37 - 2.07 ng·g干重（平均1.15 ng·g干重）和0.70 - 43.9 ng·g干重（平均9.87 ng·g干重）之间。所有测定化合物的浓度均远高于青藏高原中部或西部，PAHs浓度甚至高出两个数量级。阳坡土壤中α-六氯环己烷和滴滴涕的浓度随海拔升高而增加，但阴坡土壤中六氯环己烷和滴滴涕与海拔无显著相关性。阴坡土壤中PAHs浓度随海拔无一致的增加或减少趋势，阳坡土壤中PAHs浓度在较低海拔处较高，表明存在本地污染排放。PAHs谱以较轻组分（2环和3环占比高于85%）为主，推断研究区域内的PAHs主要受污染物长距离大气传输（LRAT）影响。PAHs的特殊诊断比值表明，PAHs主要由生物质和化石燃料的低温燃烧产生，阴坡的两个采样点可能受到油渣影响除外。较低的α-六氯环己烷/γ-六氯环己烷比值表明研究区域内的六氯环己烷是历史工业用六氯环己烷和林丹共同作用的结果。p,p'-二氯二苯醚/ p,p'-滴滴涕和o,p'-滴滴涕/ p,p'-滴滴涕比值表明滴滴涕来自历史工业用滴滴涕和三氯杀螨醇的共同作用。根据PAHs、六氯环己烷和滴滴涕的分布特征以及色季拉山的气象条件，研究区域内PAHs和OCPs的传输主要受印度季风影响。
