成都市文娱区表层土壤重金属健康风险评价

为研究成都人口密集的文娱区表层土壤的重金属污染情况以及重金属人体健康风险,采集并分析了川大望江校区、八宝广场、沙河驷马桥段、人民公园和春熙路30个表层土样中Cd、Zn、Cu和Pb元素的含量,并通过内梅罗综合污染指数法和健康风险评价法对重金属污染水平及人体健康风险进行了评价。结果发现,与土壤背景值相比重金属Pb的浓度较高（高出背景值的1~2倍）;综合指数显示除人民公园表土重金属达到中度污染外,其余各区处于轻度污染。在健康风险方面,文娱区表层土中这四种重金属尚不能对人体造成非致癌健康风险;但无论儿童还是成人,由Cd可导致的致癌风险已不能忽视。因此,应将Cd作为成都市土壤重金属污染防控工作中优先控制的重金属。     

湿润亚热带典型白云岩流域的化学剥蚀速率——以贵州施秉黄洲河流域为例

针对白云岩岩溶作用过程研究较为缺乏、白云岩地区的化学剥蚀速率报道较少等问题,本文以中国南方喀斯特施秉世界自然遗产地内黄洲河典型白云岩流域为研究区,采用流域水化学径流法,通过获得的2015年3月~2016年3月水文年内钙、镁离子的月平均浓度和高时间分辨率的流量数据,结合白云岩流域的水化学稳态行为,计算出该白云岩流域的化学剥蚀速率为46.91 mm/ka,与其他相似气候条件下白云岩流域的化学剥蚀速率相当,但比以石灰岩为主的碳酸盐岩流域的化学剥蚀速率高38%。这主要是因为在自然条件下,亚热带典型白云岩在地域尺度上有足够的时间达到溶解平衡态,进而使白云石较高的溶解度成为影响其化学剥蚀速率的主要因素。     

城市经济发展异质性对空气污染水平的影响研究

引入灰色分析法,将空气质量与产业结构之间建立关联度;利用关联度计算不同阶段各产业、行业与空气污染之间的量化关系;并根据关联度计算对各行业进行排序;以灰色关联度分析法为依据,对各行业的能源消耗量和废气排放量建立灰色系统模型,最后把各个行业对空气污染的程度结果量化后展示出来。实验结果表明,所提的方法能够清晰系统展现出城市经济发展异质性与空气污染水平的影响。     

多雨环境下山体周边建筑基坑排桩方案设计与实现研究

传统设计建筑基坑排桩方案在常规环境下能够达到建筑工程要求,但在多雨环境下对山体周边建筑并不适用,并且安全性能较低。为此提出多雨环境下山体周边建筑基坑排桩方案设计与实现。采用多种排桩模式设计,使用HPB300、HRB400级钢筋作为主体支撑;依据土压力计算公式推导出嵌固深度有效值,确定排桩具体形状参数。设置安全性验算,实现多雨环境下山体周边建筑基坑排桩方案设计。     

环境态度及其与环境行为关系的文献评述与元分析

为总结梳理环境态度定义、测量方法、影响因素及其对环境行为的影响,采用文献综述与元分析（meta-analysis）的方法,检索Elsevier ScienceDirect数据库、Web of Science Core Collection数据库、中国人民大学中文学术资源发现平台和中国知网（CNKI）中有关环境态度的文献,并从检索出的652篇相关文献中筛选出202篇核心文献、提取出43篇实证文献,对环境态度与4类环境行为之间的关系进行定量分析.结果表明,从环境态度定义和测量方式来看,国内外研究者对环境态度有着诸多定义,但都集中在“情感”“信念”“行为意图与倾向”等心理学方面;环境态度的测量方式也较多,诸多测量量表被开发,其中新环境范式量表和新生态范式量表在该领域占据着重要地位.从环境态度的影响因素来看,众多研究者从心理学和社会人口学方面进行研究,国外研究者对这两大方面有着广泛研究,价值观和道德、性别、年龄、收入、教育和知识皆为研究热点,而国内研究者比较注重环境知识这一影响因素.环境态度与环境行为之间综合相关系数为0.309（P < 0.001）,环境态度与环境行为之间呈显著正相关关系.分别考察环境态度与回收行为、能源消费行为、绿色购买行为以及出行行为等4类环境行为间的关系发现,环境态度与绿色购买行为综合相关系数为0.334（P < 0.001）,高于回收行为、能源消费行为和出行行为.研究还显示,在4类环境行为中,绿色购买行为与环境态度的相关性最强:一方面,环境态度有利于促进环境行为,因此可以通过教育、宣传等干预手段提高公众的环保态度,从而促进各类环保行为.另一方面,环境态度对于不同类型环保行为的促进效果是不同的,因此为促进公众的绿色购买行为,可以考虑增加对环境态度的教育和宣传,提高公众的环境态度;而对于促进节约用水、用电等能源消费行为,则不仅需要提高公众的环境态度,还需要结合其他更有效的干预手段（如价格干预、提示标志等）.      

Characterizing the antibiotic resistance genes in a river catchment: Influence of anthropogenic activities

Previous studies on environmental antibiotics resistance genes(ARGs) have focused on the pollution sources such as wastewater treatment plants, aquaculture and livestock farms,etc. Few of them had addressed this issue in a regional scale such as river catchment. Hence,the occurrence and abundances of 23 ARGs were investigated in surface water samples collected from 38 sites which located from the river source to estuary of the Beijiang River.Among them, 11 ARGs were frequently detected in this region and 5 ARGs(sul I, sul II, tet B,tet C, and tet W) were selected for their distribution pattern analysis. The abundances of the selected ARGs were higher in the upstream(8.70 × 10~6 copies/ng DNA) and downstream areas(3.17 × 10~6 copies/ng DNA) than those in the midstream areas(1.23 × 10~6 copies/ng DNA), which was positively correlated to the population density and number of pollution sources. Pollution sources of ARGs along the Beijiang River not only had a great impact on the abundances and diversity, but also on the distribution of specific ARGs in the water samples. Both sul I and sul II were likely originated from aquaculture farms and animal farms,tet W gene was possibly associated with the mining/metal melting industry and the electric waste disposal and tet C gene was commonly found in the area with multiple pollution sources.However, the abundance of tet B was not particularly related to anthropogenic impacts. These findings highlight the influence of pollution sources and density of population on the distribution and dissemination of ARGs at a regional scale.     

Characterization of aircraft emissions and air quality impacts of an international airport

Beijing Capital International Airport(ZBAA) is the world's second busiest airport. In this study, the emissions of air pollutants from aircraft and other sources at ZBAA in 2015 were estimated using an improved method, which considered the mixing layer height calculated based on aircraft meteorological data relay(AMDAR), instead of using the height(915 m)recommended by ICAO. The yearly emissions of NO_x, CO, VOCs, SO_2, and PM_(2.5) at the airport were 8.76 × 10~3, 4.43 × 10~3, 5.43 × 10~2, 4.80 × 10~2, and 1.49 × 10~2 ton/year, respectively. The spatial–temporal distribution of aircraft emissions was systematically analyzed to understand the emission characteristics of aircraft. The results indicated that NOxwas mainly emitted during the take-off and climb phases, accounting for 20.5% and 55.5% of the total emissions. CO and HC were mainly emitted during the taxi phase, accounting for 91.6%and 92.2% of the total emissions. Because the mixing layer height was high in summer, the emissions of aircraft were at the highest level throughout the year. Based on the detailed emissions inventory, four seasons simulation using WRF-CMAQ model was performed over the domain surrounding the airport. The results indicated that the contribution to PM_(2.5) was relatively high in winter; the average impact was about 1.15 μg/m~3 within a radius of1 km around the airport. Meanwhile, the near surroundings and southwest areas of the airport are the most sensitive to PM_(2.5).     

Railway safety climate: a study on organizational development

The safety climate of an organization is considered a leading indicator of potential risk for railway organizations. This study adopts the perceptual measurement–individual attribute approach to investigate the safety climate of a railway organization. The railway safety climate attributes are evaluated from the perspective of railway system staff. We identify four safety climate dimensions from exploratory factor analysis, namely safety communication, safety training, safety management and subjectively evaluated safety performance. Analytical results indicate that the safety climate differs at vertical and horizontal organizational levels. This study contributes to the literature by providing empirical evidence of the multilevel safety climate in a railway organization, presents possible causes of the differences under various cultural contexts and differentiates between safety climate scales for diverse workgroups within the railway organization. This information can be used to improve the safety sustainability of railway organizations and to conduct safety supervisions for the government.     

Cl~-、SO_4~(2-)和PO_4~(3-)对异养反硝化污泥的胁迫效应

反硝化菌是反硝化作用的驱动者,探明Cl~-、SO_4~(2-)和PO_4~(3-)对异养反硝化污泥(HDS)的胁迫效应,有助于含盐废水生物脱氮技术的研发和优化.选用硝酸盐还原酶(周质酶)和碱性磷酸酯酶(胞内酶)作为指标,考察了不同Cl~-、SO_4~(2-)和PO_4~(3-)浓度对HDS酶活的影响;通过观测HDS中的活菌水平和细胞形态,考察了不同Cl~-、SO_4~(2-)和PO_4~(3-)浓度对HDS微生物细胞结构的影响.结果表明,Cl~-、SO_4~(2-)和PO_4~(3-)对HDS硝酸盐还原酶的半抑制浓度分别为0.15、0.12和0.05mol/L,对碱性磷酸酯酶的半抑制浓度为1.14、0.75和0.49mol/L;高浓度Cl~-、SO_4~(2-)和PO_4~(3-)导致HDS微生物细胞膜结构破损,通透性增加,细胞物质外泄.阴离子对HDS的胁迫可分为渗透胁迫和电荷胁迫,渗透胁迫造成HDS中功能酶失活,电荷胁迫造成HDS中细胞膜破损,细胞物质外泄.     

佛山典型内河涌综合治理框架体系的研究

随着社会经济和城市化进程的快速发展,城市内河涌污染日趋严重,威胁到居民的饮水安全健康及社会经济环境的和谐发展.文中通过以佛山典型内河涌——大布涌为研究对象,采取对河涌的污染源现状进行调查分析及评价.研究过程中充分考虑到造成河涌污染的内外因、整治技术的经济可行性及环境效益等因素,最后提出了工程措施、管理手段、行政规划三个方面对城市河涌综合整治的框架体系.