Kosetice, Czech Republic--ten years of air pollution monitoring and four years of evaluating the origin of persistent organic pollutants

The regional observatory Kosetice is a central European background station. Unique continuous monitoring from 1988 on is held here. POP (persistent organic pollutant) concentration values of air samples from Kosetice taken between 1996 and 2005 were statistically processed. Values of Czech ambient air quality standards were not exceeded. Concentrations of polycyclic aromatic hydrocarbons reached two maxima, in 1996 and 2001-2002. Polychlorinated biphenyls concentrations reached the highest values in 1997 and 1998 and hexachlorocyclohexanes concentrations in 1998. DDTs, hexachlorobenzene and pentachlorobenzene were analysed as well. Long-range transport of pollutants between 2002 and 2005 was evaluated using the Potential Source Contribution Function hybrid receptor model. Indicated potential source areas of PCBs coincide with many well-known urban and industrialised areas, while the indicated potential source areas of HCHs and DDTs coincide with many agricultural and/or forested regions and the potential source areas of HCB comprise all land use types.     

Surface Consolidation of Pentelic Marble: Criteria for the selection of methods and materials - The Acropolis case (6 pp)

Goal and Scope In order to realize surface consolidation of Pentelic marble on the Acropolis monuments, we have collected the criteria that have to be fulfilled by the methods and materials without side effects on the marbles (and other stones). When the existing methods and materials did not satisfy the requirements (criteria), we invented new ones.Methods The criteria were collected from the literature, by thermodynamic and kinetic viewpoints, by laboratory experiments and in situ observations on monuments, both in Greece and in several countries in which the various methods and materials were applied. Concerning our method of ‘Inversion of sulfation’, performed by spraying a K2CO3 solution, its concentration and its temperature were controlled in order to have a total inversion (certified by liquid crystals) of gypsum back to CaCO3. For the new material of ours, ‘Reinforced Lime’, in order to eliminate the disadvantages of plain lime (low carbonation rate, low mechanical properties of CaCO3 formed, lack of carbonation in the bulk of lime), measurements of the rate of carbonation were performed in plain lime and in lime with a different CaCO3 concentration beforehand as well as in a different CO2 environments, using DTG and XRD to measure the rate of carbonation. The detachment (kg/cm2) of marble specimens stuck by lime in each case was also measured. A microscope was also used to measure the dimensions of the grain in each case as well as ammonium citrate and thymolphthalein to certify the depth of carbonation in each case. Part of the work was communicated in an international congress.Results A table with the criteria of the selection of the methods and materials for the consolidation of Pentelic marble surfaces (and other stones) was established. None of the employed methods and materials fulfilled the criteria. Only the ‘Inversion of gypsum ‘ and the ‘Reinforced Lime’ were adopted and applied to the Acropolis monuments and to other monuments in Greece and in several other countries.Recommendation and Outlook All criteria must be used for the selection of methods and materials for the consolidation of the monument surfaces. This is why we have already studied with the same procedures, methods and materials for restoration, surface cleaning and protection.     

PAH deposition to snow surface

The urban snowpack effectively acts as a collection device for atmospheric-deposited PAHs. When these PAHs are flushed out in a short time interval along with springtime snowmelt, these cause shockloading to receiving waters. In order to assess the PAH deposition and accumulation in urban snowpacks, a deposition survey of PAH for the winter months of 1991-92 from the city of Sault Ste. Marie, Ontario, Canada was undertaken. The results of the survey are interpreted in view of prevailing meteorology and various emission sources in the study area. The relative PAH deposition levels (to BaP) are compared with relative source emission fingerprints to examine consistency in sampling and analysis. While analyzing the PAH samples using the ASTM (1987) method, the problem of concentration levels being below the detection level was encountered. The ASTM method for PAH analysis was modified to enhance the detection limit of the PAHs by concentrating the PAH extract to very low volumes, on the order of 200-300 microL.     

安徽嘉山台的多极距电阻率观测

利用1990年以来安徽嘉山台的多极距电阻率观测资料进行反演分析，结果显示： 嘉山台的浅层(第一层)电阻率变化幅度最大，认为是受气象和灌溉等因素的干扰； 第二层变化幅度迅速减小； 第三层变化平稳； 深层(第四层)电阻率变化幅度比二、 三层大，可能与层厚为∝有关，原因尚须进一步研究。     

Simulation modeling and resource management

Simulation models are becoming increasingly important as tools for synthesizing and applying information in almost all aspects of land management. They are particulary valuable for predicting and comparing outcomes of alternative decisions and assumptions. Models also permit managers to consider and integrate the potential influences of a large number of variables.     

The AVI project: A bibliographical and archive inventory of landslides and floods in Italy

The AVI project was commissioned by the Minister of Civil Protection to the National Group for Prevention of Hydrogeologic Hazards to complete an inventory of areas historically affected by landslides and floods in Italy. More than 300 people, divided into 15 research teams and two support groups, worked for one year on the project. Twenty-two journals were systematically searched for the period 1918–1990, 350,000 newspaper issues were screened, and 39,953 articles were collected. About 150 experts on mass movement and floods were interviewed and 1482 published and unpublished technical and scientific reports were reviewed. The results of the AVI project, in spite of the limitations, represent the most comprehensive archiving of mass movement and floods ever prepared in Italy. The type and quality of the information collected and the methodologies and techniques used to make the inventory are discussed. Possible applications and future developments are also presented.     

Groundwater mapping: An analysis of the United States Hydrological Investigation Atlas Series

Groundwater mapping is a critical component of efficient water resource management today. Difficulties arise when highly specialized and complex groundwater data are collected and presented in map form. This is an analysis of the map content and its presentation in the USGS Hydrological Investigation Atlas Series. This analysis reveals the problems to be surmounted in mapping groundwater information. The technical nature of the groundwater data requires special design considerations.     

Inverse uncertainty characteristics of pollution source identification for river chemical spill incidents by stochastic analysis

Identifying source information after river chemical spill occurrences is critical for emergency responses. However, the inverse uncertainty characteristics of this kind of pollution source inversion problem have not yet been clearly elucidated. To fill this gap, stochastic analysis approaches, including a regional sensitivity analysis method, identifiability plot and perturbation methods, were employed to conduct an empirical investigation on generic inverse uncertainty characteristics under a well-accepted uncertainty analysis framework. Case studies based on field tracer experiments and synthetic numerical tracer experiments revealed several new rules. For example, the release load can be most easily inverted, and the source location is responsible for the largest uncertainty among the source parameters. The diffusion and convection processes are more sensitive than the dilution and pollutant attenuation processes to the optimization of objective functions in terms of structural uncertainty. The differences among the different objective functions are smaller for instantaneous release than for continuous release cases. Small monitoring errors affect the inversion results only slightly, which can be ignored in practice. Interestingly, the estimated values of the release location and time negatively deviate from the real values, and the extent is positively correlated with the relative size of the mixing zone to the objective river reach. These new findings improve decision making in emergency responses to sudden water pollution and guide the monitoring network design.

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乌鲁木齐城市地表温度时空变化与贡献度研究

伴随着新疆首府乌鲁木齐市经济快速发展,人口持续增加、城市化进程不断加快,地表温度也发生极其显著的变化。以乌鲁木齐市中心城区为研究对象,利用1990—2018年的4期Landsat卫星影像和中国科学院土地利用/覆被分类数据,采用地表温度反演、重心转移模型、空间聚类分析以及计算贡献度指数等方法,定量研究乌鲁木齐市城市化进程中地表温度的时空格局变化及土地利用/覆盖对热环境的贡献程度。结果表明,(1)1990—2018年间,研究区相对地表温度等级在<0、0—2、>8等级上面积增加,2—4、4—6、6—8等级上面积减少。面积增长最大的是<0的相对地表温度等级,面积减少最多的是6—8等级,从空间分布上看,温度区分布有从中间向外围递增的现象。(2)1990—2018年间,研究区内相对地表温度等级在0—2、2—4、4—6区域的重心均表现为先向东南,再向西,再向东北转移的趋势,相对地表温度等级>8区域的重心先向西南,再向东北转移,相对地表温度等级<0的区域温度重心一直北移,空间上呈现等级越高越靠东的现象,相对地表温度等级<0分布在中间,相对地表温度等级>8区域的重心转移距离最长,相对地表温度等级在0—2区域的重心转移距离最短。(3)研究区内的LST在空间上呈现出很强的集聚效应,从整体上均表现为等级越高集聚性越强的现象;1990—2018年间,区域热岛的集聚程度在不断降低,空间尺度临界值逐年下降。(4)1990—2018年间,研究区建设用地与水域面积增加,其余类型均在减少,面积增长最大的为建设用地,面积减少最大的耕地面积。各土地利用/覆盖类型的贡献度指数从大到小表现为草地、建设用地、未利用地、林地、水域、耕地,其中草地、建设用地、未利用地为正贡献,林地、水域、耕地为负贡献。贡献度值指数大小与面积密切相关。     

矿井下着火点位置数值模拟研究

矿井煤炭自燃是煤矿五大自然灾害之一,而煤炭自燃隐蔽着火点位置的确定是解决煤炭自燃问题的关键。本文结合实际情况将火源位置的确定问题归结为热传导方程的寻源反问题。在理想状态下,把煤矿井下热传导的三维模型简化为二维模型,建立热传导方程及初始条件和边界条件,在matlab中编制了有限差分程序对井下着火点的温度场进行了正反演模拟。数值模拟结果表明:该方法能够较准确地反演出火源的特性,并随着离散化程度的提高,离散解逐渐逼近真实解。通过本文的数值模拟我们得知有限差分法求解热传导寻源反演的方法是解决矿井隐蔽火源发火点位置的有效途径之一,对矿井防、灭火研究具有较高的理论和实际应用价值。