山东省主要城市酸沉降现状及影响因素分析

根据山东省多年降水观测资料,分析了其17个设区城市的酸雨现状,并研究了济南市和青岛市硫的干、湿沉降及其变化规律.结果表明,近5a(1997～2001年)青岛市降水酸度位列全省17城市之首,是唯一降水pH年均值低于酸雨临界值5.60的城市;山东省主要城市的降水酸度总体上呈下降趋势.济南市和青岛市近年来硫沉降总通量基本稳定或呈下降趋势,仍达10t/(km²·a)左右;在硫沉降总通量中,硫干沉降的贡献率达80%以上,而在硫干沉降通量中,SO₂干沉降的贡献率要远远高于SO₄^2-干沉降的贡献率.通过分析酸雨前体物排放强度、土壤酸碱性以及气象条件对酸沉降的影响,揭示了山东省内主要城市酸沉降的影响因子.     

持久性有机污染物(POPs)研究进展

对持久性有机污染物的定义、特点、种类和危害进行了介绍,分析了这些物质在全球自然界中存在的量和来源,阐述了POPs在区域或全球的迁移、循环模式以及POPs的预测模型,提出了对目前和将来POPs控制的研究对策和一些意见。     

Vertical distributions of soil carbon and nitrogen fractions as affected by land-uses in the Ili River Valley

In this study, soil samples were collected to a depth of 100?cm from different land-uses, including maize field (MZ), wheat field (WT), paddy field (PD), apple orchard (OC), grassland (GL) and wetland (WL) in the Ili River Valley in northwest China, to investigate the effects of land-use on vertical distributions of soil carbon (C) and nitrogen (N) fractions, and examine whether such effects were different between topsoil (0–40?cm) and subsoil (40–100?cm). The results showed that soil organic C, water-extractable organic C, microbial biomass C, total N and microbial biomass N of croplands (MZ, WT, PD and OC) were significantly lower than those of natural lands (GL and WL) in both topsoil and subsoil, indicating that contents of soil C and N fractions can be reduced by agricultural land-uses, and the reductions are not limited to topsoil. However, the contents of soil ammonium N and nitrate N showed complex trends under different land-uses, possibly due to that the plant species and agricultural practices (e.g. application rate of fertiliser and irrigation) are considerably different among land-uses. Therefore, we suggest that more nutrient inputs should be applied to croplands to improve soil fertility in the Ili River Valley.     

Occurrence of and risk posed by highly carcinogenic dibenzo[def,p]chrysene isomers in urban soil

Dibenzopyrene and its isomers are considered the most potent carcinogens of all polycyclic aromatic hydrocarbons tested to date. However, despite public concerns over their deleterious effects, they have not been extensively studied. The occurrence of four highly carcinogenic isomers of dibenzopyrene – dibenzo[def,p]chrysene, dibenzo[a,e]pyrene, dibenzo[a,i]pyrene, and dibenzo[a,h]pyrene in urban soil samples from Shanghai, China, have been determined in this study, as well as that of benzo[a]pyrene and coronene. A total of 14 peaks with ions at m/z 302 were detected by gas chromatography-mass spectrometry. Although the concentrations of benzo[a]pyrene and the sum of the 16 priority polycyclic aromatic hydrocarbons were greater than that of dibenzopyrene and its isomers, the carcinogenic potency of the latter was higher than that of benzo[a]pyrene. The results also indicate that the relative carcinogenic potency of the four dibenzopyrene isomers in the samples is higher than that of the 16 priority polycyclic aromatic hydrocarbons.     

水体低氧的早期暴露对青鳉(Oryzias latipes)后期的生长、性别比和繁殖能力的影响

水体低氧已是全球性生态问题,常以季节性、偶发性和昼夜间等不同形式存在于不同的水体中。长期低氧可影响鱼类正常的生长和繁殖,但鱼类早期生活阶段暴露于不同形式的低氧后,后期的生长和繁殖是否会受到不利影响,目前研究甚少。本研究在实验室模拟了连续低氧(2.8 mg·L~(-1)DO)(H1)、昼夜低氧(H2)和发生在胚胎器官形成时期的偶发性低氧(H3)等3种情景对青鳉胚胎的发育影响,评估了这一早期暴露对青鳉后期的生长、存活和繁殖的影响。我们发现,3种低氧方式都可以显著延长青鳉胚胎的孵化周期,引起胚胎卵黄囊吸收和鱼鳔发育异常;暴露结束120 d后,H1组青鳉成鱼的畸形率显著升高、存活率和生长速度都显著下降;H1、H2和H3组中成鱼的雌雄比都发生了改变,鱼群中以雄鱼为主,且产卵量和受精率都显著下降。结果表明,鱼类早期胚胎发育阶段所受到的低氧暴露可对后期生长和繁殖产生不利影响,对子代补充和种群稳定产生重要影响;鱼类关键发育期所经历的低氧事件,以及昼夜低氧事件所产生的生态后果不容忽视。     

水环境中重金属铜暴露下青鳉鱼的行为响应

本研究采用生物行为传感器监测青鳉鱼重金属铜暴露下的行为数据,分析不同暴露浓度(20、10、5、1和0.1 TU)下青鳉鱼的行为响应。20、10、5、1和0.1 TU的暴露浓度下青鳉鱼对重金属污染的行为反应模式符合环境胁迫阈值模型,且不同浓度梯度重金属对青鳉鱼产生不同的行为毒性效应。通过本研究,利用重金属作用下青鳉鱼的行为变化来研究重金属环境胁迫导致的生物行为响应机制,从而得到重金属暴露下生物行为的实时变化过程和趋势,可对水环境生态系统质量进行综合评价。     

灰色聚类法在水环境质量评价中的应用

本文提出运用灰色聚类法评价水质的新方法,并用该方法对某水库水质进行了评价,最后与模糊数学方法作了比较。结果证明,灰色聚类法不仅具有模糊数学的优点,又补充了其不完善之处,用灰色聚类法评价水质,比较符合实际状况.     

柴油污染包气带的气相抽提影响因素

气相抽提(SVE)是一种经济、高效的土壤原位修复技术。为了研究介质、介质含水率和通风方式对SVE去除效率的影响,并探讨实验运行过程中包气带不同深度柴油浓度的变化规律,实验利用了有机玻璃柱模拟包气带环境,开展柴油污染的SVE实验。结果表明,对于不同介质,SVE去除粗砂中柴油的效率高于中砂;不同含水率,含水率为1%的粗砂中柴油的去除率大于含水率为12%的粗砂;不同的通风方式,连续通风的效率大于间歇通风。此外,不同深度介质均出现柴油浓度先升高后降低的趋势。     

Comparisons of polybrominated diphenyl ethers levels in paired South Korean cord blood, maternal blood, and breast milk samples

Polybrominated diphenyl ethers (PBDEs), commonly used flame retardants, have been reported as potential endocrine disruptor and neurodevelopmental toxicants, thus giving rise to the public health concern. The goal of this study was to investigate the relationship between umbilical cord blood, maternal blood, and breast milk concentrations of PBDEs in South Korean. We assessed PBDE levels in paired samples of umbilical cord blood, maternal blood, and breast milk. The levels of seven PBDE congeners were measured in 21 paired samples collected from the Cheil Woman’s Hospital (Seoul, Korea) in 2008. We also measured thyroid hormones levels in maternal and cord blood to assess the association between PBDEs exposure and thyroid hormone levels. However, there was no correlation between serum thyroxin (T4) and total PBDEs concentrations. The total PBDEs concentrations in the umbilical cord blood, maternal blood, and breast milk were 10.7 ± 5.1 ng g⁻¹ lipid, 7.7 ± 4.2 ng g⁻¹ lipid, and 3.0 ± 1.8 ng g⁻¹ lipid, respectively. The ranges of total PBDE concentrations observed were 2.28-30.94 ng g⁻¹ lipid in umbilical cord blood, 1.8-17.66 ng g⁻¹ lipid in maternal blood, and 1.08-8.66 ng g⁻¹ lipid in breast milk. BDE-47 (45-73% of total PBDEs) was observed to be present dominantly in all samples, followed by BDE-153. A strong correlation was found for major BDE-congeners between breast milk and cord blood or maternal blood and cord blood samples. The measurement of PBDEs concentrations in maternal blood or breast milk may help to determine the concentration of PBDEs in infant.