MODIS气溶胶光学厚度在临安大气颗粒物监测中的应用

基于大气辐射传输理论的研究表明,AOD(气溶胶光学厚度)与地面PM(颗粒物)浓度(以ρ计)呈正相关. 利用2006—2010年MODIS晴空AOD数据产品与临安区域大气本底站监测的ρ(PM₁₀)进行相关分析发现,二者的R(相关系数)为0.431,直接相关程度较低. 根据AOD和气象能见度间的关系,获得了不同季节临安地区的气溶胶平均垂直标高,利用该垂直标高和RH(相对湿度)分别订正AOD和ρ(PM₁₀)后,二者的相关性(R为0.576) 明显提高.冬季AOD和ρ(PM₁₀)的相关性最好,R为0.765;夏、春季次之,R分别为0.643和0.608;秋季最低,为0.442. 经过对5年资料的对比分析,证实了MODIS气溶胶光学厚度经垂直标高和RH订正后,可用于临安地区地面空气污染的监测.      

新型内循环生物流化床处理豆制品废水研究

对采用射流曝气的新型内循环三相生物流化床处理豆制品废水进行了研究。结果表明 :间歇运行时 ,当循环水浓度在 30 0 0～ 4 0 0 0mg/L、循环流量在 10 0～ 2 0 0L/h之间 ,曝气量在 4 0～ 6 0L/h时 ,COD去除率可达到 95 %以上 ,去除容积负荷达到 10kg/m3 ·d以上 ;连续运行时 ,在进水流量 10 0L/h、COD <4 0 0mg/L时 ,出水COD可以达标     

基于GAM模型的西安市O3浓度影响因素解析

基于空气质量监测数据,研究了2014～2018年西安市O₃浓度和污染的变化特征,利用GAM模型揭示了气象因素对O₃浓度的影响.结果表明:①西安市O₃浓度逐年上升, 2016年开始O₃年评价指标已连续3 a超标.但随着夏季O₃污染治理的加强, 2017年后O₃浓度升幅趋缓.②O₃月均浓度变化曲线主要呈倒V型, 1～7月随气温的升高而上升, 8～12月随气温的下降而下降, 7月月均浓度最大.但在降水量偏大的年份,O₃月均浓度常在降水量最大月出现谷值,曲线形态变为M型.③2014～2018年西安市O₃污染明显加重,O₃污染时段向前延长.O₃超标率由2014年的1.9%上升到2018年的14.0%. 2016年起,O₃污染出现时间由7月提前至5月.④GAM模型拟合结果表明,气温、气压、日照时数和相对湿度与O₃浓度...     

雄安新区土壤重金属地球化学监测关键问题探讨

为构建雄安新区土壤环境质量监控网,系统获取雄安新区建设前后土壤重金属地球化学数据,长期监测新区建设过程中土壤重金属的变化趋势,在分析雄安新区土地质量地球化学调查监测数据和土壤重金属元素地球化学空间变异特征的基础上,采用统计学方法估算构建新区土壤地球化学监测网所需要的采样密度、采样数量和采样周期等参数,为后续新区土壤重金属地球化学长期监测工作提供参考.结果表明,调查区重金属As、 Cd、 Cu、 Hg和Pb元素变异系数>36%,属于高度变异元素; Cd、 Cu和Pb元素块金系数均>75%,其高度富集是在较高自然背景上出现了人为源的叠加.在置信水平P为95%和90%时,对样本平均值允许误差Δ分别为5%、 10%和15%的条件下,同时对新区土壤中8种重金属As、 Cd、 Cr、 Cu、 Hg、 Ni、 Pb和Zn进行土壤环境质量监测,最少合理采样数分别为1 077个、 270个、 120个和767个、 192个、 86个.土壤各重金属元素可监测最小变化量(MDC)介于0.0025～2.54 mg·kg^-1之间.在不同的重金属年变化速率下土壤重金属监测所需要的...     

基于多源数据的城市扩张中热环境演变及响应

改善城市热环境,提升人居环境质量是创建生态宜居城市的重要前提.目前对城市扩张与热环境关系的研究多基于遥感数据,多源数据应用较薄弱.选取西安都市圈核心区,基于2010年和2020年Landsat遥感影像测定城市扩张及热环境时空演变状况,利用兴趣点和百度热力指数等多源数据,通过地学统计分析方法对城市热环境响应机制进行多方面研究.结果表明：（1）研究区建设用地共扩张200.84 km²,面积和强度呈现“中心和外围较弱,两者之间较强”特征,扩张模式以边缘式和填充式为主.（2） 2010～2020年间,研究区整体热环境恶化,热岛区面积增加282.65 km²,热岛区蔓延与城市扩张方向一致,分布格局由“东南-西北”向“东北-西南”演变;但城市中心区平均温度下降1.09℃.（3）城市扩张与城市热环境恶化表现为强正相关;城市空间规模扩大对热环境恶化的贡献率为60.40%;各社会经济因素作用程度较弱,总体贡献率为39.60%,植被水体降温作用明显,多因素共同影响下,地表温度共增加0.241个单位.城市扩张过程中地表参数和城市二维形态变化依然是热环境变化的主要因...     

Alcohol-related deaths among young passengers: An analysis of national alcohol-related fatal crashes

Introduction: There is consensus that riding with an impaired driver (RWI) constitutes a major threat to public health. The aim of this study was to characterize the factors contributing to the motor-vehicle deaths of 15–20 year-old (y/o) passengers that RWI with a peer. Method: Secondary analyses of the 2010–2018 Fatality Analysis Reporting System. 5,673 passengers aged 15–20 y/o killed while riding in passenger cars with a driver aged 21 or older, 3,542 of these drivers also aged 15–20 y/o. Analyses were conducted between October 2019 and December 2020. Results: Sixty-three percent of the young passengers were killed while riding with a driver 15–20 y/o. Of these drivers, 26.8% had a blood alcohol concentration (BAC) >0.00 g/dL and 77.1% had a BAC ≥0.08 g/dL. Compared with those occurring during the day on weekdays, fatalities of young passengers who RWI with a peer driver with a BAC ≥ 0.08 g/dL often occurred on weekend nights (OR = 8.2) and weekday nights (OR = 5.2), and when the passenger and driver were both male (OR = 1.8). Race/ethnicity was not a significant contributor to RWI fatalities. Conclusions: Most 15–20 y/o RWI fatalities occurred on weekends, at night, when the driver was a young peer with a high BAC, and the passenger and driver were male. The high prevalence of fatalities in these high-risk situations suggests that young driver-passenger dynamics may contribute to alcohol-related fatalities. Practical Applications: To curb RWI fatalities among underage passengers, countermeasures should focus not only on underage drinking drivers and riders, but also on drinking drivers of all ages. Prevention should increase focus on situations in which both the young passenger and young driver are males.     

Residents' perception of local brownfields in rail corridor area in the City of Roanoke: the effect of people's preconception and health concerns factors

This article examines preferences of residents for nearby brownfield sites and the factors affecting preferences. 200 residents in neighborhoods along the railyard in the City of Roanoke, Virginia, participated in a survey of their preferences for different brownfield scenes. Results indicate that scenes with historical landmarks and maintained landscapes received the highest ratings, regardless of preconceptions and health concerns. These are viewed less critically and thus could mask possible harms. In contrast, scenes with scruffy vegetation and rundown buildings revealed mixed preferences. For these types, participant preferences for change versus preservation fluctuated. Lastly, scenes with industrial remnants were preferred the least. Participants tended to associate these types with toxic pollutants that may adversely affect health. This suggests that planners need to convince people that these sites can be reused if they are cleaned up. The results are used to develop more effective engagement strategies for increasing support for brownfield redevelopment projects.     

The Dieng ‘hazardscape’: a political ecology of vulnerability to natural hazards in Java’s highlands

This research article describes the construction of vulnerability to natural hazards in the Dieng Plateau of Central Java, Indonesia. The Dieng Plateau is a volcanically hazardous landscape, featuring a series of craters with a history of recurrent phreatic eruptions and emission of poisonous gases. Drawing on four months of in-depth fieldwork, this article applies the ‘hazardscape’ as a conceptual lens to describe how economic necessity and political processes frame volcanic risk, and how this influences vulnerability. Vulnerability in Dieng is linked to its history of upland settlement, the unequal spatial distribution of land prices, and the impact of internal state-led territorialisation strategies. Territorialisation strategies are characterised by the spatial designation of certain areas as ‘hazardous’, a process that historically led to the relocation of upland Javanese farmers to the outer islands as part of the politically significant transmigration programme. However, these territorial zones were locally contested, leading to the reoccupation of hazardous land with mixed outcomes for conditions of vulnerability. By unpacking the political construction of risk, through the concepts of territoriality and the hazardscape, this article demonstrates how the utilisation of hazardous land can bring economic opportunity alongside disadvantage in Java’s volcanic landscapes.