Pollution characterization and diurnal variation of PBDEs in the atmosphere of an E-waste dismantling region

Diurnal air samples were collected from the E-waste dismantling region Guiyu and the underwear industry region Chendian. This was the first report to present the diurnal variation of PBDEs in the atmosphere. The average concentrations of 11 PBDE congeners were 11,742 pg m⁻³ in the daytime, and 4830 pg m⁻³ at night in Guiyu, while the concentrations were lower in Chendian with 376 pg m⁻³ in the daytime, and 237 pg m⁻³ at night. BDE-209 accounted for 22% and 31.3% of the total PBDEs in Guiyu and Chendian, respectively. The diurnal variation trends of BDE-47, -99, -153, -183, and -209 were also analyzed in detail in the two regions.     

农作物病虫害专业化防治服务对农药施用强度的影响

农药过量施用已造成严重的负外部性。推行农作物病虫害专业化统防统治服务可以实现安全、科学、合理用药,有效缓解农业面源污染问题和提升食品的质量安全水平。为了探究病虫害专业化统防统治服务在缓解农业面源污染方面的效果,文章利用全国七省水稻病虫害专业化防治服务调查数据,基于倾向得分匹配方法(PSM),剔除样本自选择内生性问题的影响,分析农户将水稻病虫害防治环节外包给植保专业化服务组织("统防统治")与"自防自治"户相比使用农药的种类和施用次数的差异,即植保专业化防治是否取得了较好的环境效应。研究结果表明,植保专业化服务显著减少了农药施用强度,提高了无公害低毒农药的采用比例;并且其效果在小农户和规模种植大户之间存在明显差异,与采纳病虫害统防统治服务的规模种植大户相比,小规模种植户在采纳病虫害统防统治服务后在降低农药施用强度,提高无公害低毒农药的应用比例方面效果更显著。基于此,文章建议强化对植保专业化防治项目的财政扶持力度,提高病虫害专业化防治覆盖率;重点鼓励小规模种植户采纳病虫害统防统治服务;鼓励农户土地流转,促进农业生产规模化经营,加强对种植专业户的病虫害防治方面的培训和引导,并着力发挥专业大户的示范带头作用,提高统防统治的效率,从而促进食品质量安全水平的提升和农业生态环境的保护。     

近10 a武汉市城市热岛效应演变及其#br# 与土地利用变化的关系

城市化进程的加快,农村人口大量涌入城市,城市布局及局部气候改变等因素使得城市热岛效应问题日益突出,已成为当前城市环境研究热点之一。以武汉市为例,应用遥感技术与地理信息系统技术,选取2004~2015年5个时相Landsat系列影像数据,利用单窗算法反演地表温度,并以此为基础进行热岛强度分级,获取了近10 a武汉市城市热岛效应变化结果,并分析了武汉市11个辖区城市热岛效应动态变化特征及热岛效应与土地利用变化的关系。研究结果表明：（1）自2007年后,武汉市老城区热岛面积持续减少,而新城区热岛面积则持续增加,呈现出以老城区为中心向新城区扩张的趋势,至2015年,新老城区热岛面积仅相差20.74 km2;（2）东西湖区、蔡甸区、江夏区与洪山区是近些年城市热岛面积增长较为显著的辖区,其中江夏区的热岛面积年际变化最大,最高值达95.42 km2;（3）城市热岛效应与土地利用类型的面积年际平均值拟合关系显示,2004~2015年,城市热岛效应与建筑用地的R2值最大,为0.681 2,建筑用地面积的增加是城市热岛强度面积扩张的重要影响因素。     

厌氧池-复合型人工湿地系统污水处理效果的季节变化

利用厌氧池-复合型人工湿地(AT-ICW)系统处理农村生活污水,探讨工艺系统不同季节对污水的处理效果。结果表明,该工艺系统春、夏、秋季对氨氮(NH4+-N)、总磷(TP)表现出稳定且较好的去除效果,去除率分别为92.8%～97.0%和56.4%～65.9%,冬季去除率相对较差,平均去除率分别为67.1%和42.5%。NO3--N的去除效果差,四季均出现积累,累积率达到71.5%～342.9%。系统春、夏季对总氮(TN)去除效果较好,去除率为57.3%～68.9%,秋、冬季去除效果相对较差,为24.5%～35.8%。系统夏季COD去除效果好,平均去除率达到78.3%,冬、春季去除效果较差,为37.8%～43.5%。各项污水排放指标均达到城镇污水处理厂污染物排放一级A类标准。AT-ICW系统不仅处理效果好,而且运行费用低,适用于农村分散型生活污水处理。     

西安市大气中多环芳烃的季节变化及健康风险评价

对西安市2009年6月-2010年5月空气中的总悬浮颗粒（TSP）和气态样品进行了连续采样,利用GC—MS对16种PAHs进行分析。∑PAHs浓度（气相＋颗粒相）范围为39．93～1032．46ng／m^3,平均值为197．34ng／m^3;其中,冬季大气中∑PAHs浓度最大,相对浓度的范围为31．21％～72．98％,而夏季的浓度最小;检测出16种2～6环的PAHs,其中以3—4环为主。利用特征分子比值法和因子分析进行源解析,发现研究区PAHs的主要来源为燃煤和机动车尾气排放。通过苯并（a）芘（BaP）等效毒性（BEQ）和苯并（a）芘等效致癌浓度（BaPE）进行健康风险评价,结果显示,西安大气中PAHs的毒性具有明显的季节差异,特别是秋季和冬季大气中PAHs对人类的健康存在较大的潜在威胁。     

Learning About the History of Landscape Use for the Future: Consequences for Ecological and Social Systems in Swedish Bergslagen

Barriers and bridges to implement policies about sustainable development and sustainability commonly depend on the past development of social–ecological systems. Production of metals required integration of use of ore, streams for energy, and wood for bioenergy and construction, as well as of multiple societal actors. Focusing on the Swedish Bergslagen region as a case study we (1) describe the phases of natural resource use triggered by metallurgy, (2) the location and spatial extent of 22 definitions of Bergslagen divided into four zones as a proxy of cumulative pressure on landscapes, and (3) analyze the consequences for natural capital and society. We found clear gradients in industrial activity, stream alteration, and amount of natural forest from the core to the periphery of Bergslagen. Additionally, the legacy of top-down governance is linked to today’s poorly diversified business sector and thus municipal vulnerability. Comparing the Bergslagen case study with other similar regions in Russia and Germany, we discuss the usefulness of multiple case studies.     

Spatial distribution of perfluoroalkyl acids in the Pearl River of Southern China

An intensive campaign was conducted in September 2012 to collect surface water samples along the tributaries of the Pearl River in southern China. Thirteen perfluoroalkyl acids (PFAAs), including perfluorocarboxylates (PFCAs, C4–C11) and perfluorosulfonates (PFSAs, C4, C6–C8, and C10), were determined using high-performance liquid chromatography/negative electrospray ionization–tandem mass spectrometry (HPLC/(-)ESI–MS/MS). The concentrations of total PFAAs (ΣPFAAs) ranged from 3.0 to 52 ng L⁻¹, with an average of 19 ± 12 ng L⁻¹. The highest concentrations of ΣPFAAs were detected in the surface water of the Dong Jiang tributary (17–52 ng L⁻¹), followed by the main stream (13–26 ng L⁻¹) and the Sha Wan stream (3.0–4.5 ng L⁻¹). Perfluorooctanoate (PFOA), perfluorobutane sulfonate (PFBS), and perfluorooctane sulfonate (PFOS) were the three most abundant PFAAs and on average accounted for 20%, 24%, and 19% of ΣPFAAs, respectively. PFBS was the most abundant PFAA in the Dong Jiang tributary, and PFOA was the highest PFAA in the samples from the main stream of the Pearl River. A correlation was found between PFBS and PFOA, which suggests that both of these PFAAs originate from common source(s) in the region. Nevertheless, the slope of PFBS/PFOA was different in the different tributaries sampled, which indicates a spatial difference in the source profiles of the PFAAs.     

Inter-municipal cooperation for wastewater treatment: case studies from Israel

Since the beginning of the 1990s, local authorities in Israel have been engaged in promoting advanced Wastewater Treatment Plant (WWTP) projects throughout the country, resulting in the "wastewater treatment revolution" of the 1990s. These achievements are extremely important in the water-scarce country, as untreated or partially treated wastewater has become a major source of pollution of Israel's fresh-water resources, and reuse of high-quality effluents can expand the national water potential. Many of these projects are regional schemes based on a central WWTP, serving a few neighboring municipalities. This paper presents two case studies of such regional cooperation: the "Karmiel Region Union of Towns for Sewage Treatment" and the "Treatment and Reuse of Wastewater in the area of the Hadera Stream, Ltd." corporation. The findings suggest that regional cooperation can be an efficient tool in promoting advanced wastewater treatment, and has several advantages: an efficient use of limited resources (financial and land); balancing disparities between municipalities (size, socio-economic features, consciousness and ability of local leaders); and reducing spillover effects. However, some problems were reported in both cases and should be addressed.     

广东坡地红壤颗粒组成状况的研究──Ⅱ.土壤颗粒组成的空间分异

讨论了广东坡地红壤类土壤颗粒组成的空间分异现象,阐述了岩性、地形条件、水文动力学对颗粒组成空间分布的影响,指出地形条件、水动力学作用对广东坡地红壤类土壤颗粒组成的影响,在很大程度上是由广东所处区域的生物气候条件决定的。     

天津市中心城区空气污染物时间变化规律的研究

根据空气质量标准,分析了SO2、NO2和PM103项污染物不同季节,不同时期,不同时段变化规律、达标状况以及为制定相应的防治措施提供参考依据。