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1.
Releases of NaCl-rich (>100 000 mg/L) water that is co-produced from petroleum wells can adversely affect the quality of ground and surface waters. To evaluate produced water impacts on lakes, rivers and streams, an assessment of the contamination potential must be attainable using reliable and cost-effective methods. This study examines the feasibility of using geographic information system (GIS) analysis to assess the contamination potential of Cl to Skiatook Lake in the Hominy Creek drainage basin in northeastern Oklahoma. GIS-based predictions of affects of Cl within individual subdrainages are supported by measurements of Cl concentration and discharge in 19 tributaries to Skiatook Lake. Dissolved Cl concentrations measured in October, 2004 provide a snapshot of conditions assumed to be reasonably representative of typical inputs to the lake. Chloride concentrations ranged from 5.8 to 2300 mg/L and compare to a value of 34 mg/L in the lake. At the time of sampling, Hominy Creek provided 63% of the surface water entering the lake and 80% of the Cl load. The Cl load from the other tributaries is relatively small (<600 kg/day) compared to Hominy Creek (11 900 kg/day) because their discharges are relatively small (<0.44 m3/s) relative to Hominy Creek (3.1 m3/s). Examination of chemical components other than Cl in stream and lake waters indicates that many species, such as SO4, cannot be used to assess contamination potential because they participate in a number of common biogeochemical processes that alter their concentrations. 相似文献
2.
The development of integrated water resource information management system in arid regions 总被引：1，自引：1，他引：0
Mohamed A. Dawoud 《Arabian Journal of Geosciences》2013,6(5):1601-1612
Water and land-use tension are growing with the growing population of the world especially in arid region. To develop an efficient, sustainable, and integrated water and land-use resource management policy, accurate and complex information about available resources and demand centers is required. Geographical information system (GIS) provides a means of representing the real world through integrated layers of constituent spatial information using overlaying and indexing operations. In Abu Dhabi, Water Resources Information System (AWRIS) was developed. AWRIS is a centralized, GIS-based, Web-enabled integrated information management system that allows storage and management of all water resource information. The system integrates a comprehensive set of tools and applications that facilitate the efficient management of the water resources of the Emirate. All historical water resource information from more than ten existing databases and 10,000 Excel workbooks have now been compiled, quality controlled, and migrated into the central database. AWRIS is built as an Integrated Information Management System and hence designed to improve productivity by linking all relevant applications for data handling to a centralized data repository and management system. This paper outlines the main features of AWRIS which are three-folds. First, it provides full support for the Arabic language. Second, it is the first of its kind in bringing unrestricted data types into a centralized information management system, and third, it provides a wide range of tools to effectively manage information on water resources. 相似文献
3.
Mohamed O. Arnous 《Arabian Journal of Geosciences》2013,6(5):1349-1369
With the development of economic activities in the world, the construction activities have also increased. A proper surface and subsurface investigation is made to assess the general suitability of the site and to prepare an adequate and economic safe design for the proposed work. The main purpose of the current study is to create a spatial model of the geotechnical conditions and considerations by using geographic information systems (GIS) techniques to develop and analyze a site model and to plan site activities at the new extension of Suez City (SC). In the geotechnical site evaluations, GIS can be used in four ways, data integration, data visualization and analysis, planning and summarizing site activities, and data presentation. The integrated data can be displayed; manipulated and analyzed using tools build into the GIS programs, thus creating the geotechnical site model of the study area. Decisions can be made for further site activities and the results of the site activities can be integrated into the GIS site model. Interpretation of geotechnical data frequently involves assimilating information from many sites each with a unique geographical location. Interpretation of these data requires the spatial location to incorporate into the analysis. Weights are assigned to different of mechanical, physical soil properties, geological, hydrogeological, and other ancillary data. Finally, the weighted maps are integrated using a GIS based on the construction purposes for the new extension of SC for significant cost savings in design, construction and longevity. The ideal and good zones’ highest regime has been observed towards central and western regions with sporadic pockets. The marginal zones to average zones are moderately suited for shallow foundation. 相似文献
4.
Lydie Herfort Tawnya D. Peterson Fredrick G. Prahl Lee Ann McCue Joseph A. Needoba Byron C. Crump G. Curtis Roegner Victoria Campbell Peter Zuber 《Estuaries and Coasts》2012,35(3):878-891
The localized impact of blooms of the mixotrophic ciliate Myrionecta rubra in the Columbia River estuary during 2007–2010 was evaluated with biogeochemical, light microscopy, physiological, and molecular data. M. rubra affected surrounding estuarine nutrient cycles, as indicated by high and low concentrations of organic nutrients and inorganic nitrogen, respectively, associated with red waters. M. rubra blooms also altered the energy transfer pattern in patches of the estuarine water that contain the ciliate by creating areas characterized by high primary production and elevated levels of fresh autochthonous particulate organic matter, therefore shifting the trophic status in emergent red water areas of the estuary from net heterotrophy towards autotrophy. The pelagic estuarine bacterial community structure was unaffected by M. rubra abundance, but red waters of the ciliate do offer a possible link between autotrophic and heterotrophic processes since they were associated with elevated dissolved organic matter and showed a tendency for enhanced microbial secondary production. Taken together, these findings suggest that M. rubra red waters are biogeochemical hotspots of the Columbia River estuary. 相似文献
5.
6.
Mariangela G. Praça Leite Maria Augusta Gonçalves Fujaco Hermínio A. NaliniJr. Paulo de Tarso A. Castro 《Environmental Earth Sciences》2010,60(8):1723-1730
In all geological scenarios, mineral water reactions will affect the water chemistry. As such, water resources in different
rocks commonly involve different hydrogeological compartments. The aim of this work is to evaluate the influence of geology
in the geochemistry signature of Itacolomi State Park waters. To do so, a survey of the geological units in the area was carried
out, a geological/stratigraphic division was made, and its correlation with the main geological events was determined. Using
the advantages of GIS, all the catchments were delimited. Based on this division, near 30 stream and lake segments were chosen
for analyses. In each point, all physiochemical properties of the water were measured, and samples were collected to determine
the concentrations of major and trace elements by ICP–OES. The dynamics of the Itacolomi State Park rock-soil and stream water
solutions suggest that mixing of drainage waters from different bedrock and soil sources regulates stream water physical–chemical
parameters and solute concentrations. The analytical data showed a clear correlation between the chemical compositions of
the solute and the geological characteristics of the catchment. Units that are covered by iron oxide hardpan (Manso unit)
and iron-banded formations (Custódio unit) show a large amount of soluble elements, including high values of Fe and Mn. On
the other hand, the presence of high values of Al and K (Itacolomi unit) are a direct consequence of the presence of quartzite
associated with low pH values. 相似文献
7.
The mid-Cretaceous is well known for its ocean anoxic events. The causal mechanisms are controversial: stagnant deepwater, high biological productivity in the surface waters, and other possibilities have been suggested. Our study simulated the mid-Cretaceous ocean, using general circulation models combined with a marine biogeochemical cycle model to explore the relationship between thermohaline circulation and biogeochemical cycles and investigate the causes of ocean anoxic events. The simulated thermohaline circulation shows an unsteady inactive state. Oxygen concentrations in the deepwater decrease under the inactive state, but a horizontal gradient develops, with higher oxygen concentrations in the Tethys and lower concentrations in eastern Panthalassa. This is not due to the different ages of the deepwater but rather to the differences in biological productivity in the surface water, meaning that the relationship between thermohaline circulation and biogeochemical cycles under the inactive state is different from that in the present ocean. In the standard simulation, assuming the present level of the total amount of phosphate in the ocean, 29% of the bottom water is anoxic. The experiments increasing the amount of phosphate show its high sensitivity for extending the anoxic region with global-scale anoxia simulated under the doubled amount of phosphate. The high amount of phosphate would be reasonable because the inactive state would induce an imbalance of phosphate between riverine input and sediment output. Therefore, both the inactive thermohaline circulation and the increase in the total amount of phosphate in the ocean induce the global-scale anoxic condition in the deepwater. 相似文献
8.
The article considers biogeochemical features of cadmium as one of the most dangerous elements. Data on its concentrations in waters of small lakes in the European Russia (from the tundra to deserts) and large river systems (Volga, Severnaya Dvina, Pechora) are given. It is shown that, despite the relatively low concentrations of the element in waters, its enrichment factor is hundreds and thousands of units, especially in the northern regions and regions subjected to the influence of non-ferrous metallurgy. Data are presented on the bioaccumulation of cadmium within fish body systems, which is determined by the concentration of the element in waters, as well as by the water pH and the calcium content. It is proved that the highest Cd concentrations are accumulated in kidneys and liver of whitefish and salmon, causing pathological disturbances. Data are reported on the accumulation of cadmium in kidneys and liver of human population of the industrially developed Northern region under impacts of copper–nickel smelters. The similarity in tendencies of the Cd accumulation and pathological disturbances in fish and the population consuming water from contaminated sources makes it possible to recommend fish as a bioindicator of the environmental pollution by cadmium. 相似文献
9.
10.
海洋环境中重晶石的形成和保存是元素Ba生物地球化学过程的重要环节,在反演海洋古生产力领域具有重要价值。但是多年来该方面的研究主要集中在深海海域,而对河口及近海海域很少涉及。本研究使用SEM和EDX等方法对长江口及邻近海域5个断面36个站位的悬浮体中的重晶石矿物进行了系统的观察,对重晶石颗粒类型、空间分布和影响因素进行了研究。结果表明:该区重晶石颗粒包含自形晶体、长条状晶体、不规则形态晶体和集合体等4种类型,含少量Sr元素,大部分重晶石颗粒表面出现溶蚀现象;重晶石颗粒粒径主要分布在0.5~3 μm。通过研究发现,长江口及邻近海域悬浮体中重晶石的形成主要受到微环境中生物作用的控制,该区初级生产力的发育状态和重晶石颗粒的沉降差异造成重晶石空间分布具有表层含量较多、由岸向外增加的现象。 相似文献
11.
Suspended particulate matter and recent sediments from diverse oceanic sites have been investigated for their contents of lycopane. Lycopane was present in all samples, including both oxic and anoxic water column and sediments. The highest concentrations in the water column were found in surface waters of the central Pacific gyre (1.5 ng/L) and in the anoxic waters of the Cariaco Trench (1.1 ng/L) and the Black Sea (0.3 ng/L). Vertical concentration profiles suggest that lycopane is probably algal in origin. Moreover, biogeochemical conditions in anoxic zones apparently result in a secondary production of lycopane from an as yet unidentified precursor. Compound-specific carbon isotopic analyses have been carried out on lycopane from water column and sediment samples. Isotopic compositions of lycopane range between -23.6% and -32.9% and are consistent with a photoautotrophic origin. We postulate that some lycopane is produced in surface waters of the ocean, while additional lycopane is produced in anoxic zones by anaerobic microbial action on an algal precursor. 相似文献
12.
Tidal pumping drives nutrient and dissolved organic matter dynamics in a Gulf of Mexico subterranean estuary 总被引：1，自引：0，他引：1
Isaac R. Santos William C. Burnett Thorsten Dittmar I G.N.A. Suryaputra Jeffrey Chanton 《Geochimica et cosmochimica acta》2009,73(5):1325-9900
We hypothesize that nutrient cycling in a Gulf of Mexico subterranean estuary (STE) is fueled by oxygen and labile organic matter supplied by tidal pumping of seawater into the coastal aquifer. We estimate nutrient production rates using the standard estuarine model and a non-steady-state box model, separate nutrient fluxes associated with fresh and saline submarine groundwater discharge (SGD), and estimate offshore fluxes from radium isotope distributions. The results indicate a large variability in nutrient concentrations over tidal and seasonal time scales. At high tide, nutrient concentrations in shallow beach groundwater were low as a result of dilution caused by seawater recirculation. During ebb tide, the concentrations increased until they reached a maximum just before the next high tide. The dominant form of nitrogen was dissolved organic nitrogen (DON) in freshwater, nitrate in brackish waters, and ammonium in saline waters. Dissolved organic carbon (DOC) production was two-fold higher in the summer than in the winter, while nitrate and DON production were one order of magnitude higher. Oxic remineralization and denitrification most likely explain these patterns. Even though fresh SGD accounted for only ∼5% of total volumetric additions, it was an important pathway of nutrients as a result of biogeochemical inputs in the mixing zone. Fresh SGD transported ∼25% of DOC and ∼50% of total dissolved nitrogen inputs into the coastal ocean, with the remainder associated with a one-dimensional vertical seawater exchange process. While SGD volumetric inputs are similar seasonally, changes in the biogeochemical conditions of this coastal plain STE led to higher summertime SGD nutrient fluxes (40% higher for DOC and 60% higher for nitrogen in the summer compared to the winter). We suggest that coastal primary production and nutrient dynamics in the STE are linked. 相似文献
13.
Patrick R. Hutchins Erik M. Smith Eric T. Koepfler Richard F. Viso Richard N. Peterson 《Estuaries and Coasts》2014,37(3):736-750
Groundwater discharge is increasingly recognized as a significant source of nutrient input to coastal waters, relative to surface water inputs. There remains limited information, however, on the extent to which nutrients and organic matter from each of these two flowpaths influence the functional responses of coastal microbial communities. As such, this study determined dissolved organic carbon (DOC) and nutrient concentrations of surface water runoff and groundwater from both an urbanized and a relatively pristine forested drainage basin near Myrtle Beach, South Carolina, and quantified the changes in production rates and biomass of phytoplankton and bacterioplankton in response to these inputs during two microcosm incubation experiments (August and October, 2011). Rainwater in the urbanized basin that would otherwise enter the groundwater appeared to be largely rerouted into the surface flowpath by impervious surfaces, bypassing ecosystem buffers and filtration mechanisms. Surface runoff from the developed basin was most enriched in nutrients and DOC and yielded the highest production rates of the various source waters upon addition to coastal waters. The metabolic responses of phytoplankton and bacterioplankton were generally well predicted as a function of initial chemical composition of the various source waters, though more so with bacterial production. Primary and bacterial productivities often correlated at reciprocal time points (24-h measurement of one with the 72-h measurement of the other). These results suggest human modification of coastal watersheds enhances the magnitude of dissolved constituents delivered to coastal waters as well as alters their distributions between surface and groundwater flowpaths, with significant implications for microbial community structure and function in coastal receiving waters. 相似文献
14.
Application of MODFLOW and geographic information system to groundwater flow simulation in North China Plain, China 总被引：2，自引：0，他引：2
Shiqin Wang Jingli Shao Xianfang Song Yongbo Zhang Zhibin Huo Xiaoyuan Zhou 《Environmental Geology》2008,55(7):1449-1462
MODFLOW is a groundwater modeling program. It can be compiled and remedied according to the practical applications. Because
of its structure and fixed data format, MODFLOW can be integrated with Geographic Information Systems (GIS) technology for
water resource management. The North China Plain (NCP), which is the politic, economic and cultural center of China, is facing
with water resources shortage and water pollution. Groundwater is the main water resource for industrial, agricultural and
domestic usage. It is necessary to evaluate the groundwater resources of the NCP as an entire aquifer system. With the development
of computer and internet information technology it is also necessary to integrate the groundwater model with the GIS technology.
Because the geological and hydrogeological data in the NCP was mainly in MAPGIS format, the powerful function of GIS of disposing
of and analyzing spatial data and computer languages such as Visual C and Visual Basic were used to define the relationship
between the original data and model data. After analyzing the geological and hydrogeological conditions of the NCP, the groundwater
flow numerical simulation modeling was constructed with MODFLOW. On the basis of GIS, a dynamic evaluation system for groundwater
resources under the internet circumstance was completed. During the process of constructing the groundwater model, a water
budget was analyzed, which showed a negative budget in the NCP. The simulation period was from 1 January 2002 to 31 December
2003. During this period, the total recharge of the groundwater system was 49,374 × 106 m3 and the total discharge was 56,530 × 106 m3 the budget deficit was −7,156 × 106 m3. In this integrated system, the original data including graphs and attribution data could be stored in the database. When
the process of evaluating and predicting groundwater flow was started, these data were transformed into files that the core
program of MODFLOW could read. The calculated water level and drawdown could be displayed and reviewed online. 相似文献
15.
《Russian Geology and Geophysics》2014,55(5-6):562-581
The results of more than 40 years long authors’ investigations in the field of the freshwater (river input) and marine (ocean waters) hydrospheres are summarized. The latest estimations of the global average concentrations of many chemical elements in river water and suspended matter and in ocean water and suspended matter are presented. It is shown that particulate suspended forms of many elements are predominant in river waters (“rivers are the kingdom of suspended forms of elements”), while their dissolved forms prevail in ocean waters (“ocean is the kingdom of dissolved forms of elements”). Sedimentary and biogeochemical processes of the river material transformation in the river-sea mixing zone (the so-called “marginal filter of the ocean”) were studied thoroughly. It was shown that radical quantitative and qualitative changes of dissolved and particulate suspended substances take place in this zone, resulting in the governed transformation of dissolved forms into suspended particulate forms and their following deposition on the bottom. The first data on the losses of 35 chemical elements in the river-sea mixing zone are presented. These data prove that the concentrations of dissolved elements in river and ocean waters are in regular and close relationship with their losses in the river-sea mixing zone and with the types of element distribution in ocean water column (conservative, biogenic, and lithogenic). This indicates the existence of a geochemical system in the entire (freshwater and marine) hydrosphere, which calls for deep and detailed investigations. 相似文献
16.
Rare earth elements in the water column of Lake Vanda, McMurdo Dry Valleys, Antarctica 总被引：2，自引：0，他引：2
We present data on the composition of water from Lake Vanda, Antarctica. Vanda and other lakes in the McMurdo Dry Valleys of Antarctica are characterized by closed basins, permanent ice covers, and deep saline waters. The meromictic lakes provide model systems for the study of trace metal cycling owing to their pristine nature and the relative simplicity of their biogeochemical systems. Lake Vanda, in the Wright Valley, is supplied by a single input, the Onyx River, and has no output. Water input to the lake is balanced by sublimation of the nearly permanent ice cap that is broken only near the shoreline during the austral summer. The water column is characterized by an inverse thermal stratification of anoxic warm hypersaline water underlying cold oxic freshwater.Water collected under trace-element clean conditions was analyzed for its dissolved and total rare earth element (REE) concentrations by inductively coupled plasma mass spectrometry. Depth profiles are characterized by low dissolved REE concentrations (La, Ce, <15 pM) in surface waters that increase slightly (La, 70 pM; Ce, 20 pM) with increasing depth to ∼55 m, the limit of the fresh oxic waters. Below this depth, a sharp increase in the concentrations of strictly trivalent REE (e.g., La, 5 nM) is observed, and a submaximum in redox sensitive Ce (2.6 nM) is found at 60- to 62-m depth. At a slightly deeper depth, a sharper Ce maximum is observed with concentrations exceeding 11 nM at a 67-m depth, immediately above the anoxic zone. The aquatic concentrations of REE reported here are ∼50-fold higher than previously reported for marine oxic/anoxic boundaries and are, to our knowledge, the highest ever observed at natural oxic/anoxic interfaces. REE maxima occur within stable and warm saline waters. All REE concentrations decrease sharply in the sulfidic bottom waters. The redox-cline in Lake Vanda is dominated by diffusional processes and vertical transport of dissolved species driven by concentration gradients. Furthermore, because the ultraoligotrophic nature of the lake limits the potential for organic phases to act as metal carriers, metal oxide coatings and sulfide phases appear to largely govern the distribution of trace elements. We discuss REE cycling in relation to the roles of redox reactions and competitive scavenging onto Mn- and Fe-oxides coatings on clay sized particles in the upper oxic water column and their release by reductive dissolution near the anoxic/oxic interface. 相似文献
17.
María Celia García 《GeoJournal》2007,70(4):289-296
The paper focuses on the concentration of nitrates detected in superficial waters (lake and streams) and groundwater (wells)
used as sources of water supply. It attempts to determine the level of risk due to the presence of urban industrial uses and
correlate it with the quality of urban life, in order to determine social vulnerability to the risk of industrial contamination.
A geographic information system (GIS) was constructed with layers for various census data, topographic and landuse features
and the location of water samples. An index of quality of life was developed using selected variables. This was then compared
to the essential services provision data and the results of the water sample analyses. The concentration of nitrates (mg/l
or ppm) in the water samples was determined. These values were translated into maps of contaminants, which were then correlated
with their possible sources and with the quality of life of the population affected. The concentration of nitrates in wells
has been considered alarming, but more concern has been expressed about concentrations in the public water supply network.
Spatial correlation between areas with high risk of contaminated water and areas with the worst quality of life, indicates
the importance of controlling chemical contamination, and demands improvements in the public water supply network and revision
of the theory of social vulnerability. 相似文献
18.
Artesian basins contain the largest mineral water resources of the world. There are several types of mineral therapeutic water: sulfate, chloride, radon-rich, iron-rich waters, etc. Artesian basins occupy very large areas in Russia. However, genesis of water and brines is still not very clear. This is one of the most important hydrogeological problems that is being attempted to solve for many years. Most of the Russian hydrogeologists traditionally consider that these waters are of sedimentary origin. However, higher concentrations of bromine, iodine, iron, radon and other balneologically active components can be of different origin, for example, of infiltration or juvenile water. As an example, two areas will be considered – West-Siberian basin and East-European artesian area.West-Siberian artesian basin has very distinct latitudinal and vertical zonation. Latitudinal zonation is caused by climate changes from north to south. As for the vertical zonation, mineralization and chemical composition change in the vertical cross-section and from the periphery to the center within the same aquifer. The main mineral water resources of West-Siberian artesian basin are concentrated in Mesozoic rocks. Brackish waters and low-saturated brines without specific components are used for medical purposes. The most well-known spa is Karachi, which exploits chloride-hydrocarbonate brackish water. Sodium chloride bromine and iodine-bromine waters are used at other health resorts. It is possible to organize extraction of iodine from brines of Tcherkashinsko-Tobolskoe occurrence in Tumen region.East-European artesian area occupies most of the Russian Platform. The most widespread types of mineral water within the Russian Platform are sodium-chloride and magnesium-sulfate waters and brines. Such well-known spas, like Moscow mineral waters, Krainka, Staraya Russa and many others, belong to this type. Resources of these waters are definitely connected with sedimentogenic processes. The upper hydrodynamic zone contains iron-rich, hydrogen sulfide, and sometimes radon-rich water. Their formation is caused by the interaction between waters of infiltration and sedimentary genesis, or between infiltration waters and host rocks. One of the examples is Polustrovo iron-rich water. There are industrially valuable waters containing bromine and iodine.The resources of therapeutic water of sedimentary basins allow to increase balneological potential of spas in Russia. 相似文献
19.
陆地生态系统与气候相互作用的研究进展 总被引：43，自引：4，他引：43
陆地生态系统与气候系统通过地面与大气之间能量平衡、水汽交换和生物地球化学循环相互作用,影响大气中温室气体浓度和气溶胶,继而影响气候变化。较系统分析总结了当代国际上陆地生态系统与气候相互作用的最新研究进展。首先介绍了陆地生态系统与气候相互作用的机制与过程,总结了陆地生态系统与气候相互作用研究的三个发展阶段,以及当代相互作用的过程模拟研究中三类主要的全球生态系统模型,即生物物理模型、生物地理模型和生物地球化学模型。并介绍了气候对生态系统变化的响应,即两种主要的反馈机制。最后,对未来的研究方向和重点作了分析。 相似文献
20.
针对辽河油田地区地下水开采引起的降落漏斗形成及扩展、咸水入侵与水质污染等问题,已开展了大量研究。提出利用VB编程软件、MO组件在ArcView GIS和Access数据库的基础上建立一个集数据库管理、水质评价、水位和水量预测、空间分析等功能于一体的地下水资源管理决策支持系统的总体开发思路。该系统将信息管理与决策支持有效融合,在运用GIS功能的同时,嵌入专业模型,实现人机交互、信息共享。 相似文献