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1.
In order to examine the extent of the As enrichment and the factors influencing this enrichment in the groundwater of Eastern Croatia, groundwater samples were collected from 56 production wells in two counties, Osijek-Baranja and Vukovar-Srijem, suspected to be more affected. Hydrochemical analyses were performed at all locations including in situ As speciation at 32 locations. Arsenic was detected in 46 out of 56 groundwater samples with total As concentrations up to 491 μg/L. Thirty-six of the studied wells yielded groundwater with total As concentrations that exceeded the WHO Maximum Contaminant Level for arsenic in drinking water of 10 μg/L. Only inorganic As species were detected with arsenite As(III) as the predominant form. The spatial distribution of As in the groundwater was significantly linked with geological, geomorphological and hydrogeological development of the alluvial basin of the Drava and Sava rivers. The most probable groundwater As sources are deeper sediments from the Middle and Upper Pleistocene. The results obtained suggest that biogeochemical processes controlling As concentration in the groundwater are complex and location-specific. Reductive dissolution of Fe oxides, desorption of As from Fe oxides and/or clay minerals as well as competition for the sorption sites with organic matter and phosphate could be the principal mechanisms that control As mobilization. The extent of those processes vary in the different parts of the Drava and Sava depressions and could be linked to different site related parameters, such as lithology, mineralogy, local hydrology and hydrogeology; thus different processes of As mobilization have been proposed for the different types of water in relation to groundwater evolution.  相似文献   
2.
Dynamics of the Kopački Rit (Croatia) wetland floodplain water regime   总被引:1,自引:1,他引:0  
Kopa?ki Rit Nature Park is part of the Danube River natural floodplain and one of the last oases of wild life in the Danube River Basin. Due to its extraordinary value, it was inscribed on the list of Wetlands of International Importance in 1993. More than 2,000 species have been registered in this area, which consists of lakes, canals, grassland, marshland and forests. Even the number of investigations which have been performed on its biological and ecological features, hydrological and water resources characteristics, as a prerequisite for ecohydrological analyses, are still rather unknown in the scientific community. Mainly the Danube River and partly the River Drava cause flooding of Kopa?ki Rit and inundations enter the area from both the northern and southern parts. Results of hydrological and meteorological analysis show a decreasing trend of both mean and minimum, annual water levels in the Rivers Drava and Danube (respectively 1.8 and 1.38 cm/year). These reductions in water level can reduce the replenishment periods of Kopa?ki Rit Nature Park. In addition, a significant rise of mean annual air temperature and consequently water temperature (data 1988–2011) may be causing increasing evapotranspiration and loss of water within Kopa?ki Rit. But an encouraging counteracting finding is that, the results of frequency analysis show, even a discharge of 5-years’ return period on the River Danube inundates 70 % of the Danube floodplain and Kopa?ki Rit Nature Park.  相似文献   
3.
锦州东港电力有限公司矿泉水水源地位于辽西中部断陷盆地锦州盆地的北端。地处中新生代上侏罗统及白垩系构成的对称向斜,NNE新华夏系断裂构造经由锦州盆地通过。工作区第四系覆盖6-14m,下伏孙家湾组(K2S)砂质泥岩、砂砾岩和义县组(K1y)火山碎屑岩、英安岩、安山岩及火山凝灰角砾岩。对该区进行地质水文资料综合分析的基础上,采用电阻率联合剖面、高密度电阻率法、电测深(电阻率、衰减时及极化率)多种物探电法综合勘查,确定断裂构造位置、产状及赋水性。经验证获得涌水量312t/d具有商业价值的矿泉水水源地。这一工作方法在辽西火山岩贫水区进行水资源勘查具有推广意义。  相似文献   
4.
5.
辽宁义县萤石矿床成矿与构造的关系   总被引:3,自引:0,他引:3  
辽宁义县地区的岩浆期后充填热液交代型萤石矿床的成矿质量与构造的型式和性质有着密切关系。研究证实,构造性质控制着形成萤石矿床的规模和质量。构造既是成矿热液运移通道,更重要的是提供有效的成矿贮矿空间。背斜构造成矿最好,成群出现近于平行的压扭性断裂构造破碎带次之,这两种性质的构造均能形成具有工业价值的萤石矿床。而张性(张扭性)构造破碎带中只能见到规模较小的萤石矿化。  相似文献   
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7.
Fishmeal is a critically important feed ingredient for use in animal (e.g., poultry and pigs) and aquaculture production (e.g., salmon, trout and shrimp). There is great concern that increasing demand for fishmeal will place stress on the world's pelagic fisheries and may undermine the sustainability of aquaculture systems. Our research shows that after 1998 the fishmeal sector changed. The change has increased costs for animal and fish producers, which seems to have acted as a stimulus for innovation. The results have considerable implications for the management and health of pelagic fisheries.  相似文献   
8.
PRB技术在矿区地质填图及图件编绘中应用的几点尝试   总被引:2,自引:1,他引:1  
运用PRB数字填图技术进行矿产地质填图及图件编绘的基本做法是:用手持GPS对地质点定位,并将坐标值及相关简单属性存于其中,用接收软件将存于GPS中的数据导出,然后在比较通用的软件如Excel.surfer8、Grapher4、CAD、Mapgis等软件中进行处理,最后在Mapgis中加挂属性,进行建库分析。实践过程中尚遇一些难题,如GPS的精度问题、地形图矢量化工作量大且各自为战、地质花纹及颜色填充混乱不统一等问题,有待于今后逐步完善。  相似文献   
9.
Abstract

This article analyses the national circumstances and major factors underpinning China's energy demand and supply, energy-related emissions, and consequently China's sustainable development. These factors include the huge, still growing, and aging population, rapid economic growth, ongoing industrialization and urbanization, environmental and health concerns at local, regional and global level. Against such background analysis, the article explores the potential and constraints of non-fossil fuel, fuel-switching to natural gas, economy restructuring and clean coal technology in mitigating emissions of greenhouse gases (GHG) and ensuring energy supply in China. The authors reiterate the importance of improving energy efficiency in China and discuss how to integrate renewable energy into rural development. The article concludes with an in-depth discussion about redefining development goals, the equity issue in climate change process, and the linkage with sustainable development.  相似文献   
10.
 气候与环境变化对我国的影响表现在自然、社会、经济和政治等各个方面。通过对我国气候与环境影响的评估,从生态系统、农业、水资源、重大工程等方面进行了论述。在此基础上,从冰冻圈、生态系统、土地退化、工业、交通、服务业、城市与生活等几个方面进行了气候影响的利弊分析。进而评估了气候变化对我国区域可持续发展的影响,提出了气候变化的适应与减缓对策。  相似文献   
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