Distribution and vertical migration of polycyclic aromatic hydrocarbons in forest soil pits of southeastern Tibet

PAHs could be transported to Tibetan Plateau in accompany with atmospheric circulation. The forest regions were found be an important sink for PAHs, while their distributions and migrations in forest are still uncertain. In this study, soil profile samples were collected in southeastern Tibet and the concentrations, distributions, and migration of PAHs in forest region were investigated. The PAHs levels in the forest soils were at the low end of remote sites, ranged from 27.4 to 120.3 ng g^?1 on a dry weight based. Due to low ambient temperature and high organic carbon content, enrichment of PAHs was found in higher altitude on north side. According to the soil profiles, the vertical distributions of PAHs in organic layers were mainly influenced by pedogenesis, while the vertical distributions in mineral layers were dominated by downward leaching effect. Enrich factor (EF) of PAHs was estimated, and the values in organic layers were positively correlated with the octanol–air partition coefficients (K _OA), but EFs in mineral layers decreased with the K _OA values. PAHs in the surface soils on the north side of forest were relatively stable, while the migration of PAHs on the south sides and other clearing sites was more active. The leaching rates of PAHs in clearing site ranged between 1.42 and 29.3%. The results from this study are valuable on the characterization of PAHs in Tibetan Plateau.     

基于着生硅藻指数的梧桐河水生态健康评价

在黑龙江省梧桐河,调查了13个点位的着生硅藻群落结构和水环境特征,应用8种硅藻指数对该河流水生生态系统进行健康评价,并在此基础上应用主成分分析、相关分析、冗余分析、箱型图分析等统计分析方法研究了影响梧桐河着生藻类群落的主要环境因子和8种硅藻指数在梧桐河的适用情况。结果显示:梧桐河存在一定程度的环境污染,优势种以小型异极藻(Gomphonema parvulum)等耐污种为主。8个硅藻指数中,硅藻属指数(Generic Index of Diatom,GI)、澳大利亚河流硅藻生物评价指数(Diatom Index for Australian Rivers,DIAR;Diatom Species Index for Bioassessment of Australian Rivers,DSIAR)评价结果偏差较大,在梧桐河不适用;相似度指数(Jaccard Index,JI)与富营养化硅藻指数(Trophic Diatom Index,TDI)评价结果较为严格,评分明显偏低;硅藻污染耐受指数(Pollution Tolerance Index,PTI)、硅藻生物评价指数(Diatom Bioassessment Index,DBI)和生物硅藻指数(Biological Diatom Index,BDI)在梧桐河流域适用性最好。根据冗余分析(RDA),将梧桐河流域点位分为3组,第一组点位为中-重度污染,主要影响因子为流速和总磷;第二组点位为轻-中度污染,主要影响因子为磷酸盐、氨氮和溶解氧;第三组点位为轻污染-清洁,主要影响因子为p H和电导率。     

江苏省空气质量预报准确度及改进方法分析

介绍了江苏省重污染天气监测预报预警系统以及大气重污染预警会商流程,将2015年13个地级市的模式预报、人工预报结果分别与实际观测值进行比较。结果表明:人工预报更准确,PM_(2.5)日均值、臭氧日最大8 h平均值、AQI 3个指标人工预报和实况的相关性分别比模式预报高出12.8%、0.3%、11.4%,平均标准误差(MNE)分别低20.7%、3.1%、23.1%。依据国家空气质量预报技术指南评分办法,对各市2015年全年空气质量级别为"良"时进行评分。通过开展07∶00预报更新,使2015年上半年空气质量预报级别得分平均提高了0.9分,全年级别得分平均提高了2.6分;通过改进模式预报参数,使PM_(2.5)日均预报值、臭氧日最大8 h平均预报值、AQI预报值和实际观测值的相关性比上年同期分别提高26.0%、5.0%、33.9%,MNE分别降低3.6%、31.3%、7.6%。     

瑞士土壤环境监测网络构建与运行对中国的启示

“十三五”期间,中国初步构建了国家土壤环境监测网并开展了监测工作。当前,国家层面土壤环境监测网络的构建和运行还处于起步阶段,笔者选取土壤环境监测开展较为成熟的瑞士土壤环境监测网(NABO)作为研究对象,综述了NABO的技术体系及多年来的土壤环境监测结果,并结合中国土壤环境监测工作现状进行讨论,认为NABO在监测网络建立、指标选取、数据分析等方面建立了较为成熟的技术体系,未来中国国家土壤环境监测网可在此方面借鉴瑞士经验。     

Application of CMB model for source apportionment of polycyclic aromatic hydrocarbons (PAHs) in coastal surface sediments from Rizhao offshore area, China

Polycyclic aromatic hydrocarbons (PAHs) in coastal surface sediments from Rizhao offshore area were analyzed by gas chromatography–mass spectrometry. A chemical mass balance (CMB) model developed by the U.S. Environmental Protection Agency (EPA), CMB8.2, was used to apportion sources of PAHs. Seven possible sources, including coal residential, coal power plant, diesel engines exhaust, gasoline engines exhaust, coke oven, diesel oil leaks, and wood burning, were chosen as the major contributors for PAHs in coastal surface sediments. To establish the fingerprints of the seven sources, source profiles were collected from literatures. After including degradation factors, the modified model results indicate that diesel oil leaks, diesel engines exhaust, and coal burning were the three major sources of PAHs. The source contributions estimated by the EPA’s CMB8.2 model were 9.25%, 15.05%, and 75.70% for diesel oil leaks, diesel engines exhaust, and coal burning, respectively.     

浅谈如何开展环境监测类设施公众开放日活动

随着城市工业化的快速发展,突发性环境污染事故逐渐增多,因此,环境公众开放日活动显得尤为重要。本文结合实际情况,探讨如何开展监测类公众开放日活动。     

Background biomonitoring of residue levels of 137 pesticides in the blood plasma of the general population in Beijing

Due to the widespread use of pesticides, human exposure to pesticides is possible and can potentially cause adverse impacts on public health. We measured 137 pesticides including organophosphorus, organochlorine, pyrethroid and carbamate pesticides together with various herbicides in 100 human blood samples collected from the general population in Beijing. The samples were analysed by triple quadrupole tandem gas chromatography-mass spectrometry. In total, 24 organochlorine pesticides, 5 pyrethroid pesticides and 6 organophosphorus pesticides were detected. The detection rates of HCB, α-HCH, β-HCH, γ-HCH, p,p′-DDE and quintozene were 99, 96, 74, 72, 96 and 95%, respectively. No statistically significant gender difference in the blood concentrations of the pesticides was found. Consistent with the trend of the increasing β-HCH, p,p′-DDE and quintozene concentrations with age, a strong positive correlation between the age and concentrations of β-BHC, p,p′-DDE and quintozene was observed.     

The distribution and enrichment characteristics of copper in soil and <Emphasis Type="Italic">Phragmites australis</Emphasis> of Liao River estuary wetland

The aims of the present investigation were to reveal the distribution and enrichment characteristics of copper in soil and Phragmites australis of Liao River estuary wetland. The concentrations of copper in root, stem, leaf, and ear of Phragmites australis as well as in soil were determined to study the absorption capacity of copper by wild Phragmites australis of Liao River estuary wetland. The study was carried out at test pool of the Shenyang Agricultural University, and the experimental materials (soil, irrigating water and Phragmites australis) were derived from Liao River estuary wetland. The concentrations of copper in soil and Phragmites australis were 16.4441 to 49.0209 mg/kg and 0.8621 to 89.5524 mg/kg, respectively. The results indicated that the enrichment coefficients of copper in different tissues of Phragmites australis changed with the growth of Phragmites australis. The results revealed that the enrichment coefficients of copper in the whole Phragmites australis were greater than 1 at each growing stage of the Phragmites australis. The results also showed that the transfer coefficients of Phragmites australis to copper changed with the growth of Phragmites australis. The results revealed that the Phragmites australis had a good removal effect on copper from soil and had some characteristics of copper hyperaccumulator.     

Distribution characteristics of polycyclic aromatic hydrocarbons in sediments and biota from the Zha Long Wetland, China

In this paper, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in biota (reed, grass, mussel, fish, and red-crowned crane) and sediments collected from seven locations in the Zha Long Wetland. PAHs were recovered from the sediments and biota by ultrasonic extraction and then analyzed by means of gas chromatography-mass spectrometry. The total PAH concentrations were 244–713 ng/g dw in sediments, 82.8–415 ng/g dw in plants and 207–4,780 ng/g dw in animals. The total sediment PAH concentrations were categorized as lower to moderate contamination compared with other regions of China and the world. In the plant samples, the accumulation abilities of reed roots and stems for PAHs were higher than those of grass roots. In addition, the concentration of individual PAHs in mussel muscles was the highest in all of the animal samples, followed by fish, feeding crane fetuses, and wild crane fetuses. Compositional analysis suggests that the PAHs in the sediments from the Zha Long Wetland were derived from incomplete biomass combustion. Risk assessment shows that the levels of PAHs in sediments are mostly lower than the effects range mean value (effects range mean), whereas only naphthalene in all sample sites was higher than the effects range low value. It is worthwhile to note that benzo(b)fluoranthene, benzo(k)fluoranthene, indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were detected in crane fetal, which have potential carcinogenicity for organisms from the Zha Long Wetland.     

江苏省2014-2016年臭氧污染区域特征分析

分析2014—2016年江苏省O₃污染状况,以及苏北、苏中和苏南3个典型区域O₃年度、季度、日变化和频度占比等分布特征。结果表明,江苏省的O₃空间分布呈现北低南高,2014—2016年的O₃超标占比由18.4%上升至34.9%;2016年苏北、苏中和苏南地区O₃-8h第90百分位数与2014年相比,上升2.7%,21.8%和3.3%;3个区域夏季O₃-8h均值最高,春、秋2季次之,冬季最低;O₃-1h日变化呈单峰状态,最低值出现在06:00—07:00,最高值出现在15:00—16:00;2016年3个地区的O₃频度占比均呈正态分布,主要集中在40~80 μg/m³,所占比例均>15%;苏中和苏南区域2016和2014年相比O₃频率占比的变化幅度较大,苏北地区变化幅度不大。指出,江苏省的O₃污染程度在逐年提高,污染范围从苏南逐渐往中部和北部城市扩大。