Journal articles: 'Ground and surface water environments'

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Rossi, P., N. Dörfliger, K. Kennedy, I. Müller, and M. Aragno. "Bacteriophages as surface and ground water tracers." Hydrology and Earth System Sciences 2, no. 1 (March 31, 1998): 101–10. http://dx.doi.org/10.5194/hess-2-101-1998.

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Abstract. Bacteriophages are increasingly used as tracers for quantitative analysis in both hydrology and hydrogeology. The biological particles are neither toxic nor pathogenic for other living organisms as they penetrate only a specific bacterial host. They have many advantages over classical fluorescent tracers and offer the additional possibility of multi-point injection for tracer tests. Several years of research make them suitable for quantitative transport analysis and flow boundary delineation in both surface and ground waters, including karst, fractured and porous media aquifers. This article presents the effective application of bacteriophages based on their use in differing Swiss hydrological environments and compares their behaviour to conventional coloured dye or salt-type tracers. In surface water and karst aquifers, bacteriophages travel at about the same speed as the typically referenced fluorescent tracers (uranine, sulphurhodamine G extra). In aquifers of interstitial porosity, however, they appear to migrate more rapidly than fluorescent tracers, albeit with a significant reduction in their numbers within the porous media. This faster travel time implies that a modified rationale is needed for defining some ground water protection area boundaries. Further developments of other bacteriophages and their documentation as tracer methods should result in an accurate and efficient tracer tool that will be a proven alternative to conventional fluorescent dyes.

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Chin, David A., and Xing Qi. "Ground Water under Direct Influence of Surface Water." Journal of Environmental Engineering 126, no. 6 (June 2000): 501–8. http://dx.doi.org/10.1061/(asce)0733-9372(2000)126:6(501).

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Poyiadji, Eleftheria, Nikolaos Nikolaou, and Petros Karmis. "GROUND FAILURE DUE TO GYPSUM DISSOLUTION." Bulletin of the Geological Society of Greece 43, no. 3 (January 24, 2017): 1393. http://dx.doi.org/10.12681/bgsg.11315.

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Gypsum in Hellas and Cyprus occurs in three different types: (a) bedded (mainly of Messinian age in Cyprus and Crete), (b) domes (mainly western Hellas and Crete), and (c) as bodies, fragments and cementing material in Triassic conglomerate formations (western Hellas). Ground failure caused by void migration to the surface, resulting from gypsum dissolution, is a common phenomenon in such areas, which are also found in other European countries (e.g., Italy, Spain, Switzerland, U.K., Lithuania, Latvia, Poland, Romania, Turkey, Ukraine and Russia). In this paper three different case studies of ground failure are presented: Cyprus, Crete (Viannos) and Corfu. Engineering geological, stratigraphical, geophysical, hydrogeological and hydrogeochemical studies of these areas, revealed the direct relationship between surface runoff, and ground water circulation with the rate of gypsum dissolution, the subsequent development of karst hollows, and the associated ground failure in urban and suburban environments. Two main models were defined, according to different mechanisms of gypsum dissolution. The first model is associated with the erosion activity of surface runoff, the second with the dissolving capacity of ground water. Risks to the urban and suburban environments were assessed, and guidelines as well as mitigation measures were proposed.

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Abdullateef Abdullahi Ibrahim, Muhammad Abdullahi Ibrahim, and Ali Gambo Yusuf. "Implications of industrial effluents on surface water and ground water." World Journal of Advanced Research and Reviews 09, no. 03 (March 30, 2021): 330–36. http://dx.doi.org/10.30574/wjarr.2021.9.3.0110.

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The industrial discharge carries significant level of contaminants to the surface water and ground water. Whereas the quality of freshwater is very vital because is highly use by human for drinking, bathing, agriculture and other needs. The presence of contaminants from industries within the water may reduce the yield of crops and the growth of plants; it is also harmful to the aquatic living organisms, it alters the surface water and ground water quality. Industrial pollution is one of the major factors causing degradation of the environment, affecting the water we use, the air we breathe and the soil we live on. Hence, the pollution of water is arguably the most serious threat to current human welfare. This paper review elucidates reasons of contamination of surface water by the industrial effluents, highlights major causes of ground water pollution; the work also indicates some industrial discharges and their contaminants.

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Lin, Henry. "Surface and Ground Water, Weathering, and Soils." Journal of Environmental Quality 35, no. 5 (September 2006): 1967–68. http://dx.doi.org/10.2134/jeq2006.0618br.

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Yan, Ailan, Xianyan Guo, Donghui Hu, and Xiaoyang Chen. "Reactive Transport of NH4+ in the Hyporheic Zone from the Ground Water to the Surface Water." Water 14, no. 8 (April 12, 2022): 1237. http://dx.doi.org/10.3390/w14081237.

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Nowadays, ammonia nitrogen (NH4+) pollution gets more and more attention in drinking water sources. This study investigated the main behavior of biogeochemical NH4+ from groundwater to surface water in a hyporheic zone (HZ) sediment from a reservoir. The experiments were conducted using synthetic groundwater to investigate ammonium transformation. The results indicated that ammonium concentration decreased, apparently resulting from the influence of microbial oxidation and ion exchange with Ca2+, Mg2+, K+, and Na+. However, all the ammonium in the sediment was oxidized, then the adsorbed NH4+ became bioavailable by being released back when NH4+ concentration decreased in the aqueous phase. The results showed NH4+ behavior in a HZ where the aerobic and anaerobic environments frequently exchange, with different hydrological conditions controlled by a strong coupling between microbial activities, geochemistry, hydrology, and ion exchange.

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Poulain, Thibault, José Mendez, Gilbert Hénaff, and Laurent de Baglion. "Influence of the Strain Rate on the Low Cycle Fatigue Life of an Austenitic Stainless Steel with a Ground Surface Finish in Different Environments." Advanced Materials Research 891-892 (March 2014): 1320–26. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.1320.

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This paper focuses on the influence of strain rate in Low Cycle Fatigue (LCF) of a 304L austenitic stainless steel at 300 °C in different environments (secondary vacuum, air and Pressurized Water Reactor (PWR) water environment). Moreover test samples are ground to obtain a surface finish rougher than all that could be found in nuclear power plants. Different strain rates (4x10-3, 1x10-4and 1x10-5s-1) are studied, with a triangular waveform at a total strain amplitude of ±0.6%. The influence of strain rate on cyclic stress-strain behavior and fatigue life is firstly analyzed in secondary vacuum, considered as a non-active environment. Then, interactions between stain rate and environmental effects in Air and in PWR environment are presented. In all environments, a decrease in strain rate leads to a negative strain rate dependence of the stress response and a reduction in fatigue life. Finally, SEM observations of fatigue striations in PWR environment indicate a crack propagation rate enhancement when the strain rate is decreased.

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Tkáčová, Klára, Nadežda Števulová, Zdeněk Bastl, Pavel Stopka, and Magdaléna Bálintová. "Changes in surface area and composition during grinding of silicon in environments of various quality." Journal of Materials Research 10, no. 11 (November 1995): 2728–35. http://dx.doi.org/10.1557/jmr.1995.2728.

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Changes in particle size, surface properties, and composition brought about by planetary grinding of silicon in air and various permittivity liquids were investigated. Using a variety of spectroscopic techniques (ESR, IRS, and XPS), a mechanically induced surface oxidation was proved. While at grinding in air and organic liquids a part of the centers originating from dangling orbitals on SiIII are preserved, the properties of water-ground silicon are fully governed by the oxide surface shell. The most effective particle size reduction and surface protection can be reached by grinding in nonpolar liquids.

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Riveros-Iregui, Diego A., and Jennifer Y. King. "Isotopic evidence of methane oxidation across the surface water-ground water interface." Wetlands 28, no. 4 (December 2008): 928–37. http://dx.doi.org/10.1672/07-191.1.

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Gisnås, Kjersti, Sebastian Westermann, Thomas Vikhamar Schuler, Kjetil Melvold, and Bernd Etzelmüller. "Small-scale variation of snow in a regional permafrost model." Cryosphere 10, no. 3 (June 3, 2016): 1201–15. http://dx.doi.org/10.5194/tc-10-1201-2016.

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Abstract. The strong winds prevalent in high altitude and arctic environments heavily redistribute the snow cover, causing a small-scale pattern of highly variable snow depths. This has profound implications for the ground thermal regime, resulting in highly variable near-surface ground temperatures on the metre scale. Due to asymmetric snow distributions combined with the nonlinear insulating effect of snow, the spatial average ground temperature in a 1 km2 area cannot be determined based on the average snow cover for that area. Land surface or permafrost models employing a coarsely classified average snow depth will therefore not yield a realistic representation of ground temperatures. In this study we employ statistically derived snow distributions within 1 km2 grid cells as input to a regional permafrost model in order to represent sub-grid variability of ground temperatures. This improves the representation of both the average and the total range of ground temperatures. The model reproduces observed sub-grid ground temperature variations of up to 6 °C, and 98 % of borehole observations match the modelled temperature range. The mean modelled temperature of the grid cell reproduces the observations with an accuracy of 1.5 °C or better. The observed sub-grid variations in ground surface temperatures from two field sites are very well reproduced, with estimated fractions of sub-zero mean annual ground surface temperatures within &pm;10 %. We also find that snow distributions within areas of 1 km2 in Norwegian mountain environments are closer to a gamma than to a lognormal theoretical distribution. The modelled permafrost distribution seems to be more sensitive to the choice of distribution function than to the fine-tuning of the coefficient of variation. When incorporating the small-scale variation of snow, the modelled total permafrost area of mainland Norway is nearly twice as large compared to the area obtained with grid-cell average snow depths without a sub-grid approach.

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Behl, Elizabeth. "Computer Models for Fate Assessment During the Registration Process: Data Needs." Weed Technology 6, no. 3 (September 1992): 696–700. http://dx.doi.org/10.1017/s0890037x00036071.

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Computer models designed to simulate the fate and transport of pesticide residues in surface runoff and water that recharges shallow aquifers are used at several stages in the regulation of pesticides. Models can be a powerful tool to identify environments in which pesticides are more mobile and are more likely to impact ground-water quality. Models can also be used to highlight pesticides that can contaminate surface or ground water at an early stage of the registration process. At present, models are utilized primarily as comparative tools to identify which compounds should be examined on a priority basis. Results may be used to calibrate numerical models and estimate the long term impact on the environment from the use of a particular product or its alternatives. To date, field monitoring studies have been required for over 40 chemicals by the Office of Pesticide Programs (OPP) to evaluate the leaching potential of pesticides under realistic usage conditions. As the capabilities of models improve and linkages are developed between databases and the models, computer simulation models will play an increasingly important role in the Environmental Protection Agency's (EPA's) efforts to manage pesticide use to prevent adverse effects on the environment.

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Verstraeten, I. M., J. D. Carr, G. V. Steele, E. M. Thurman, K. C. Bastian, and D. F. Dormedy. "Surface Water‐Ground Water Interaction: Herbicide Transport into Municipal Collector Wells." Journal of Environmental Quality 28, no. 5 (September 1999): 1396–405. http://dx.doi.org/10.2134/jeq1999.00472425002800050002x.

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Gisnås, K., S. Westermann, T. V. Schuler, T. Litherland, K. Isaksen, J. Boike, and B. Etzelmüller. "A statistical approach to represent small-scale variability of permafrost temperatures due to snow cover." Cryosphere 8, no. 6 (November 14, 2014): 2063–74. http://dx.doi.org/10.5194/tc-8-2063-2014.

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Abstract. In permafrost environments exposed to strong winds, drifting snow can create a small-scale pattern of strongly variable snow heights, which has profound implications for the thermal regime of the ground. Arrays of 26 to more than 100 temperature loggers were installed to record the distribution of ground surface temperatures within three study areas across a climatic gradient from continuous to sporadic permafrost in Norway. A variability of the mean annual ground surface temperature of up to 6°C was documented within areas of 0.5 km2. The observed variation can, to a large degree, be explained by variation in snow height. Permafrost models, employing averages of snow height for grid cells of, e.g., 1 km2, are not capable of representing such sub-grid variability. We propose a statistical representation of the sub-grid variability of ground surface temperatures and demonstrate that a simple equilibrium permafrost model can reproduce the temperature distribution within a grid cell based on the distribution of snow heights.

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Gisnås, K., S. Westermann, T. V. Schuler, T. Litherland, K. Isaksen, J. Boike, and B. Etzelmüller. "A statistical approach to represent small-scale variability of permafrost temperatures due to snow cover." Cryosphere Discussions 8, no. 1 (January 22, 2014): 509–36. http://dx.doi.org/10.5194/tcd-8-509-2014.

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Abstract. In permafrost environments exposed to strong winds, drifting snow can create a small-scale pattern of strongly variable snow heights which has profound implications for the thermal regime of the ground. Arrays of 26 to more than 100 temperature loggers were installed to record the distribution of ground surface temperatures within three study areas across a climatic gradient from continuous to sporadic permafrost in Norway. A variability of the mean annual ground surface temperature of up to 6 °C was documented within areas of 0.5 km2. The observed variation can to a large degree be explained by variation in snow height. Permafrost models employing averages of snow height for grid cells of e.g. 1 km2 are not capable of representing such sub-grid variability. We propose a statistical representation of the sub-grid variability of ground surface temperatures and demonstrate that a simple equilibrium permafrost model can reproduce the temperature distribution within a grid-cell based on the distribution of snow heights.

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Gyawu-Asante, F. N., S. Aikins, and R. B. Voegborlo. "Effects of surface gold mining on surface and groundwater bodies in Bibiani, Ghana." Journal of Science and Technology (Ghana) 37, no. 1 (December 15, 2017): 9–24. http://dx.doi.org/10.4314/just.v37i1.2.

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A study of the water sources from Bibiani and its environs was conducted between November, 2009 and April, 2010 to determine whether contamination (of water sources) from (these parameters) physical, chemical and trace metal in Bibiani is as a result of mining or geochemicaland biochemical processes within the environment. This was done by collecting water samples from two streams, two rivers, three boreholes (BHs) and three hand dug wells (HDWs). These were analysed in the laboratory. Levels of Arsenic (As), Iron (Fe), Manganese (Mn), pH, TotalDissolved Solids (TDS), Electrical Conductivity (EC), Temperature, Alkalinity, Hardness, Phosphate (P) and Cyanide (CN) in water sources were determined. Mining related contaminants detected in water samples were As, CN, Mn and Fe. It was observed that surface water pH values were generally higher than that of groundwater samples. As concentrations in surface water samples were higher compared to that of groundwater samples. Also, CN concentration in ground water samples was higher than that of surface water. Ground water contained higher concentration of Mn than surface water; the opposite can be said of Fe concentration in surfacewater which was higher than that of ground water. The study also observed that pH, TDS, EC, total alkalinity, total hardness , Arsenic and total cyanide levels in the HDW and BH samples showed 100% compliance with the WHO and EPA limits while Mn and Fe levels indicated traces of non – compliance. Compared to WHO / EPA guidelines, few water sources had one or moretrace metal (Fe, As and Mn) levels outside acceptable limits for drinking. However, most of the levels were safe for human consumption.Keywords: Surface, gold mining, quality, degradation, Bibiani

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Roy, A., A. Royer, O. St-Jean-Rondeau, B. Montpetit, G. Picard, A. Mavrovic, N. Marchand, and A. Langlois. "Microwave snow emission modeling uncertainties in boreal and subarctic environments." Cryosphere Discussions 9, no. 5 (October 27, 2015): 5719–73. http://dx.doi.org/10.5194/tcd-9-5719-2015.

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Abstract. This study aims to better understand and quantify the uncertainties in microwave snow emission models using the Dense Media Radiative Theory-Multilayer model (DMRT-ML) with in situ measurements of snow properties. We use surface-based radiometric measurements at 10.67, 19 and 37 GHz in boreal forest and subarctic environments and a new in situ dataset of measurements of snow properties (profiles of density, snow grain size and temperature, soil characterization and ice lens detection) acquired in the James Bay and Umijuaq regions of Northern Québec, Canada. A snow excavation experiment – where snow was removed from the ground to measure the microwave emission of bare frozen ground – shows that small-scale spatial variability in the emission of frozen soil is small. Hence, variability in the emission of frozen soil has a small effect on snow-covered brightness temperature (TB). Grain size and density measurement errors can explain the errors at 37 GHz, while the sensitivity of TB at 19 GHz to snow increases during the winter because of the snow grain growth that leads to scattering. Furthermore, the inclusion of observed ice lenses in DMRT-ML leads to significant improvements in the simulations at horizontal polarization (H-pol) for the three frequencies (up to 20 K of root mean square error). However, the representation of the spatial variability of TB remains poor at 10.67 and 19 GHz at H-pol given the spatial variability of ice lens characteristics and the difficulty in simulating snowpack stratigraphy related to the snow crust. The results also show that for ground-based radiometric measurements, forest emission reflected by the surface leads to TB underestimation of up to 40 K if neglected. We perform a comprehensive analysis of the components that contribute to the snow-covered microwave signal, which will help to develop DMRT-ML and to improve the required field measurements. The analysis shows that a better consideration of ice lenses and snow crusts is essential to improve TB simulations in boreal forest and subarctic environments.

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Nouri, H., S. Beecham, A. M. Hassanli, and G. Ingleton. "Spatial and temporal distribution of drainage and solute leaching in heterogeneous urban vegetation environments." Hydrology and Earth System Sciences Discussions 10, no. 5 (May 29, 2013): 6695–721. http://dx.doi.org/10.5194/hessd-10-6695-2013.

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Abstract. Deep percolation enhancement from recycled wastewater irrigation may contribute to salt accumulation and water table elevation that can ultimately cause soil and ground water degradation. The spatial and temporal variation of drainage rate and solute leaching were investigated in an urban park containing heterogeneous landscape plants that were irrigated with recycled wastewater. Field monitoring was undertaken at Veale Gardens in the Adelaide Parklands, Australia. Based on the landscape variation in Veale Gardens, two landscape zones were defined: one being largely covered with turf grasses with few trees and shrubs (MG) with the second zone being mostly trees and shrubs with intermittent turf grasses (MT). Experiments were performed using two zero-tension lysimeters placed horizontally 100 cm below ground to monitor the spatio-temporal behaviour of drained water and nutrient loadings for four seasons. The outcomes showed a large spatial and temporal variation of drainage quantity and quality in the MT and MG zones. The low vegetation cover in the MG zone resulted in more drained water than in the high vegetation cover (MT zone). In both zones, more drainage water was collected in winter than in other seasons. This is in spite of the input water showing a maximum rate in summer. The seasonal salinities measured in the two lysimeters showed very similar trends with the lowest salinity rate in autumn with the levels increasing through winter and spring. Chemical analyses of the leachate solute indicated no detrimental impact from using recycled wastewater during the study period.

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Erg, K., E. Reinsalu, and I. Valgma. "GEOTECHNICAL PROCESSES AND SOIL-WATER MOVEMENT WITH TRANSPORT OF POLLUTANTS IN THE ESTONIAN OIL SHALE MINING AREA." Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 1 (June 26, 2006): 79. http://dx.doi.org/10.17770/etr2003vol1.1984.

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One of the most important industries of Northeast Estonia is oil shale mining. Ground movements caused by mining reach the ground surface easily due to shallow location of workings. A new, artificial topography is formed on undermined areas, where the ground surface depressions are alternating with rising grounds. When the Quaternary cover contains loamy sediments, the surface water will accumulate in the depressions. The response of usable lands on undermined areas depends on the degree of changes in the relief and water regime. The accumulation of solid residues by oil shale mines and processing plants has resulted in numerous ash hills, which are polluting the environment. The streams are polluted by phenols, oil products and sulphates. The main source of water supply is groundwater in the oil shale basin. The hydrostratigraphic section is represented by three aquifers. Two (Quaternary and Ordovician) of these aquifers are affected by the human activity. Intensive water consumption has caused a fall in the water level in these aquifers. Due to oil shale production the concentration of Ca2+, Mg2+, SO4 2- and Cl- contained in the groundwater from the Ordovician deposits is noticeably higher than in the water with a natural background level. The natural water chemical regime is restored at the cessation of mining.

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Hossain, Md Lokman, Satyajit Roy Das, and Mohammed Kamal Hossain. "Impact of Landfill Leachate on Surface and Ground Water Quality." Journal of Environmental Science and Technology 7, no. 6 (October 15, 2014): 337–46. http://dx.doi.org/10.3923/jest.2014.337.346.

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Abermann, J., A. Fischer, A. Lambrecht, and T. Geist. "On the potential of very high-resolution repeat DEMs in glacial and periglacial environments." Cryosphere 4, no. 1 (January 25, 2010): 53–65. http://dx.doi.org/10.5194/tc-4-53-2010.

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Abstract. The potential of high-resolution repeat DEMs was investigated for glaciological applications including periglacial features (e.g. rock glaciers). It was shown that glacier boundaries can be delineated using airborne LIDAR-DEMs as a primary data source and that information on debris cover extent could be extracted using multi-temporal DEMs. Problems and limitations are discussed, and accuracies quantified. Absolute deviations of airborne laser scanning (ALS) derived glacier boundaries from ground-truthed ones were below 4 m for 80% of the ground-truthed values. Overall, we estimated an accuracy of +/−1.5% of the glacier area for glaciers larger than 1 km2. The errors in the case of smaller glaciers did not exceed +/−5% of the glacier area. The use of repeat DEMs in order to obtain information on the extent, characteristics and activity of rock glaciers was investigated and discussed based on examples.

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Puckett, Larry J., Celia Zamora, Hedeff Essaid, John T. Wilson, Henry M. Johnson, Michael J. Brayton, and Jason R. Vogel. "Transport and Fate of Nitrate at the Ground-Water/Surface-Water Interface." Journal of Environmental Quality 37, no. 3 (May 2008): 1034–50. http://dx.doi.org/10.2134/jeq2006.0550.

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Habib, MA, MA Hoque, MS Islam, MM Islam, and MN Islam. "Phosphate Level in Some Selected Surface and Ground Water Bodies of Rajshahi City Corporation." Journal of Environmental Science and Natural Resources 8, no. 1 (August 24, 2015): 129–33. http://dx.doi.org/10.3329/jesnr.v8i1.24685.

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Optimum PO4-P level in surface and ground water is essential for maintaining good health and environment. In this study, the PO4-P level was measured for 148 different water samples collected from ponds, supply tape and tube-well of 8 different areas of Rajshahi City Corporation. All the sites of surface water bodies crossed the United States Environmental Protection Agency (USEPA) criterion of 0.01-0.03 mg L-1 PO4P to be free from eutrophication. Among the samples, 4.2% were within the range (0.025-0.1 mg L-1) of onset of eutrophication while 95.8% crossed the hyper-eutrophication level (> 0.10 mg L-1). However, most of the ground (83.1%) and tap (92.7%) water were excellent in quality for drinking with respect to PO4P level (<1 mg L-1). Only 15.3% of ground water and 7.3% of tap water were good quality and a negligible amount (1.6%) of ground water was fair quality.J. Environ. Sci. & Natural Resources, 8(1): 129-133 2015

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Filipovic, Dejan, and Danijela Obradovic. "Quality of the surface and ground water in the municipality of Subotica." Glasnik Srpskog geografskog drustva 88, no. 1 (2008): 101–16. http://dx.doi.org/10.2298/gsgd0801101f.

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All the activities and development processes existing on the territory of the municipality of Subotica result in certain effects on the environment. Based on the analysis of the present environmental state, the authors identified certain influences on the quality of the surface and ground water. It is necessary to pay attention much more on the problem of the pollution and protection of the surface and ground water, considering insufficiency of water recourses on this territory, as well as its threatened quality.

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Schreiber, J. D., S. Smith, and C. M. Cooper. "The occurrence, distribution, and remediation of transient pollution events in agricultural and silvicultural environments." Water Science and Technology 33, no. 2 (January 1, 1996): 17–26. http://dx.doi.org/10.2166/wst.1996.0034.

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Transient pollution events occur in runoff from both agricultural and silvicultural environments. In agricultural runoff, transient pollution events may be associated with sediment, nutrients, and pesticides. Depending upon hydrological conditions, these events may be responsible for most of the yearly yield of sediment, nutrients, and pesticides, and may have a profound effect on the ecological health of streams and reservoirs, limiting seasonal primary productivity, changing the balance of functional groups, and altering reproductive cycles. Transient pollution events are most noticeable in surface runoff, but are also observable in shallow ground water. Such occurrences in both runoff and shallow ground water may be associated with natural seasonal events including the fall leaching of crop residues, or with cultural activities including the application of fertilizers and pesticides. In either case, rainfall distribution and intensity become important factors in the magnitude of the transient pollution event. Best management practices (BMPs) must be designed to remediate transient pollution in agricultural storm events. Not only must total storm agrichemical loading to aquatic ecosystems be reduced, but also the transient agrichemical concentration peaks occurring within the storm hydrograph.

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Zanacic, Enisa, and Dena W. McMartin. "Calibration and Validation of Calcium Carbonate Precipitation Potential (CCPP) Model for Strontium Quantification in Cold Climate Aquatic Environments." Environments 9, no. 6 (June 18, 2022): 74. http://dx.doi.org/10.3390/environments9060074.

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The ability to robustly quantify the potential for strontium precipitation and scaling in both natural surface waters and water infrastructure systems is limited. In some regions, both surface and ground water supplies contain significant concentrations of naturally occurring radionuclides, such as strontium, that can accumulate in water, soils and sediments, media, and living tissues. Methods for quantifying and predicting the potential for these occurrences are not readily available nor have they been tested and calibrated to cold region aquatic environments. Through extensive literature review, it was determined that a modified calcium carbonate precipitation potential (CCPP) model offered a scientifically credible approach to filling that knowledge gap in both the science and engineering of strontium fate and transport in water. The results from previous field and laboratory experiments were compiled to not only elucidate the fate and transport of strontium in water systems, but also to calculate the logarithmic distribution coefficient, λ, for strontium under co-precipitation conditions. Lambda (λ) is both time- and water-quality sensitive and must be measured as water mixes from source to receiving environment to determine continuous loss of Sr from the water phase. The data were collected to develop the strontium precipitation potential model that can be used in surface water quality assessment. The tool was then applied to pre-existing, publicly available, and extensive datasets for several rivers in Saskatchewan, Canada, to validate the model and produce estimates for strontium precipitation potential in those rivers.

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Cui, Yaoping, Yiming Fu, Nan Li, Xiaoyan Liu, Zhifang Shi, Jinwei Dong, and Yan Zhou. "A Novel Approach for Automatic Urban Surface Water Mapping with Land Surface Temperature (AUSWM)." Remote Sensing 14, no. 13 (June 25, 2022): 3060. http://dx.doi.org/10.3390/rs14133060.

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The principal difficulty in extracting urban surface water using remote-sensing techniques is the influence of noise from complex urban environments. Although various methods exist, there are still many sources of noise interference when extracting urban surface water, and automatic cartographic methods with long time series are especially scarce. Here, we construct an automatic urban surface water extraction method from the combination of traditional water index, urban shadow index (USI), and land surface temperature (LST) by using the Google Earth Engine cloud computing platform and Landsat imagery. The three principal findings derived from the application of the method were as follows. (i) In comparison with autumn and winter, LST in spring and summer could better distinguish water from high-reflection ground objects, shadows, and roads and roofs covered by asphalt. (ii) The overall accuracy of Automated Water Extraction Index (AWEIsh) in Zhengzhou was 77.5% and the Kappa coefficient was 0.55; with consideration of the USI and LST, the overall accuracy increased to 96.0% and the Kappa coefficient increased to 0.92. (iii) During 1990–2020, the area of urban surface water in Zhengzhou increased, with an evident trend in expansion from 11.51 km2 in 2008 to 49.28 km2 in 2020. Additionally, possible omissions attributable to using 30m-resolution imagery to extract urban water areas were also discussed. The method proposed in this study was proven effective in eliminating the influence of noise in urban areas, and it could be used as a general method for high-accuracy long-term mapping of urban surface water.

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Hövelmann, Jörn, Christine Putnis, and Liane Benning. "Metal Sequestration through Coupled Dissolution–Precipitation at the Brucite–Water Interface." Minerals 8, no. 8 (August 10, 2018): 346. http://dx.doi.org/10.3390/min8080346.

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The increasing release of potentially toxic metals from industrial processes can lead to highly elevated concentrations of these metals in soil, and ground- and surface-waters. Today, metal pollution is one of the most serious environmental problems and thus, the development of effective remediation strategies is of paramount importance. In this context, it is critical to understand how dissolved metals interact with mineral surfaces in soil–water environments. Here, we assessed the processes that govern the interactions between six common metals (Zn, Cd, Co, Ni, Cu, and Pb) with natural brucite (Mg(OH)2) surfaces. Using atomic force microscopy and a flow-through cell, we followed the coupled process of brucite dissolution and subsequent nucleation and growth of various metal bearing precipitates at a nanometer scale. Scanning electron microscopy and Raman spectroscopy allowed for the identification of the precipitates as metal hydroxide phases. Our observations and thermodynamic calculations indicate that this coupled dissolution–precipitation process is governed by a fluid boundary layer at the brucite–water interface. Importantly, this layer differs in composition and pH from the bulk solution. These results contribute to an improved mechanistic understanding of sorption reactions at mineral surfaces that control the mobility and fate of toxic metals in the environment.

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Gisnås, K., S. Westermann, T. V. Schuler, K. Melvold, and B. Etzelmüller. "Small-scale variation of snow in a regional permafrost model." Cryosphere Discussions 9, no. 6 (December 8, 2015): 6661–96. http://dx.doi.org/10.5194/tcd-9-6661-2015.

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Abstract. The strong winds prevalent in high altitude and arctic environments heavily redistribute the snow cover, causing a small-scale pattern of highly variable snow depths. This has profound implications for the ground thermal regime, resulting in highly variable near-surface ground temperatures on the meter scale. Asymmetric snow distributions combined with the non-linear insulating effect of snow also mean that the spatial average ground temperature in a 1 km2 area can not necessarily be determined based on the average snow cover for that area. Land surface or permafrost models employing a coarsely classified average snow depth will therefore not yield a realistic representation of ground temperatures. In this study we employ statistically derived snow distributions within 1 km2 grid cells as input to a regional permafrost model in order to represent sub-grid variability of ground temperatures. This is shown to improve the representation of both the average and the total range of ground temperatures: the model results show that we reproduce observed sub-grid ground temperature variations of up to 6 °C, with 98 % of borehole observations within the modelled temperature range. Based on this more faithful representation of ground temperatures, we find the total permafrost area of mainland Norway to be nearly twice as large as what is modelled without a sub-grid approach.

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Dornbusch, Uwe. "Ground Survey Methods for Mixed Sand and Gravel Beaches in Intertidal Environments: A Comparison." Journal of Coastal Research 263 (May 2010): 451–64. http://dx.doi.org/10.2112/08-1134.1.

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Wu, Dai-Ling, Min Zhang, Lu-Xi He, Hai-Yan Zou, You-Sheng Liu, Bei-Bei Li, Yuan-Yuan Yang, Chongxuan Liu, Liang-Ying He, and Guang-Guo Ying. "Contamination profile of antibiotic resistance genes in ground water in comparison with surface water." Science of The Total Environment 715 (May 2020): 136975. http://dx.doi.org/10.1016/j.scitotenv.2020.136975.

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Cagle, Alexander E., Alona Armstrong, Giles Exley, Steven M. Grodsky, Jordan Macknick, John Sherwin, and Rebecca R. Hernandez. "The Land Sparing, Water Surface Use Efficiency, and Water Surface Transformation of Floating Photovoltaic Solar Energy Installations." Sustainability 12, no. 19 (October 2, 2020): 8154. http://dx.doi.org/10.3390/su12198154.

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Floating photovoltaic solar energy installations (FPVs) represent a new type of water surface use, potentially sparing land needed for agriculture and conservation. However, standardized metrics for the land sparing and resource use efficiencies of FPVs are absent. These metrics are critical to understanding the environmental and ecological impacts that FPVs may potentially exhibit. Here, we compared techno-hydrological and spatial attributes of four FPVs spanning different climatic regimes. Next, we defined and quantified the land sparing and water surface use efficiency (WSUE) of each FPV. Lastly, we coined and calculated the water surface transformation (WST) using generation data at the world’s first FPV (Far Niente Winery, California). The four FPVs spare 59,555 m2 of land and have a mean land sparing ratio of 2.7:1 m2 compared to ground-mounted PVs. Mean direct and total capacity-based WSUE is 94.5 ± 20.1 SD Wm−2 and 35.2 ± 27.4 SD Wm−2, respectively. Direct and total generation-based WST at Far Niente is 9.3 and 13.4 m2 MWh−1 yr−1, respectively; 2.3 times less area than ground-mounted utility-scale PVs. Our results reveal diverse techno-hydrological and spatial attributes of FPVs, the capacity of FPVs to spare land, and the utility of WSUE and WST metrics.

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Pan, Xicai, Stefan Jaumann, Jiabao Zhang, and Kurt Roth. "Efficient estimation of effective hydraulic properties of stratal undulating surface layer using time-lapse multi-channel GPR." Hydrology and Earth System Sciences 23, no. 9 (September 10, 2019): 3653–63. http://dx.doi.org/10.5194/hess-23-3653-2019.

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Abstract. Multi-scale soil architectures in shallow subsurface are widespread in natural and anthropogenic depositional environments, and acquisition of the surface stratal structure and hydrological properties are essential in quantifying water cycling. Geophysical methods like ground-penetrating radar (GPR) can provide quantitative information like soil architecture and spatiotemporal soil water content distribution for the shallow layer. Concerning the informative multi-dimensional water flow in the surface layer with an undulating bottom at the plot scale, this study assesses the feasibility of efficiently estimating soil hydraulic properties using a few time-lapse multi-channel GPR observations, namely soil water storage and layer thickness of the surface layer, at reclamation land near an old river channel. We show that effective hydraulic properties of the surface layer can be obtained with a small number of time-lapse GPR measurements during a rainfall event. Additionally, we analyze the effect of some key factors controlling the informative lateral water redistribution on the results of the proposed approach using synthetic simulations.

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Kneisel, C., A. Bast, and D. Schwindt. "Quasi-3-D resistivity imaging – mapping of heterogeneous frozen ground conditions using electrical resistivity tomography." Cryosphere Discussions 3, no. 3 (October 30, 2009): 895–918. http://dx.doi.org/10.5194/tcd-3-895-2009.

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Abstract. Up to now an efficient 3-D geophysical mapping of the subsurface in mountainous environments with rough terrain has not been possible. A merging approach of several closely spaced 2-D electrical resistivity tomography (ERT) surveys to build up a quasi-3-D model of the electrical resistivity is presented herein as a practical compromise for inferring subsurface characteristics and lithology. The ERT measurements were realised in a small glacier forefield in the Swiss Alps with complex terrain exhibiting a small scale spatial variability of surface substrate. To build up the grid for the quasi-3-D measurements the ERT surveys were arranged as parallel profiles and perpendicular tie lines. The measured 2-D datasets were collated into one quasi-3-D file. A forward modelling approach – based on studies at a permafrost site below timberline – was used to optimize the geophysical survey design for the mapping of the mountain permafrost distribution in the investigated glacier forefield. Quasi-3-D geoelectrical imaging is a useful method for mapping of heterogeneous frozen ground conditions and can be considered as a further milestone in the application of near surface geophysics in mountain permafrost environments.

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Lehmann-Horn, J. A., J. O. Walbrecker, M. Hertrich, G. Langston, A. F. McClymont, and A. G. Green. "Imaging groundwater beneath a rugged proglacial moraine." GEOPHYSICS 76, no. 5 (September 2011): B165—B172. http://dx.doi.org/10.1190/geo2011-0095.1.

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With the changing precipitation patterns and melting of mountain glaciers and permafrost that result from global warming, information on the distribution of groundwater in mountainous terrains is becoming increasingly important for developing prudent resource and hazard management strategies. Obtaining this information across topographically craggy and variably frozen ground in a cost-effective and nonintrusive manner is challenging. We introduce a modified 2D surface nuclear magnetic resonance (NMR) tomographic technique that allows us to account for substantial variations in surface topography in locating and quantifying groundwater occurrences in rugged mountains. Because contact with the ground is not necessary, it is a rare geophysical technique not affected by sensor-to-ground coupling problems common in high mountain environments. To demonstrate the efficacy of the tomographic imaging scheme, we invert a large multioffset surface NMR data set collected across a partially ice-cored proglacial terminal moraine in the Canadian Rocky Mountains. Our preferred model contains a 2- to 5-m-thick water layer, the top of which has practically the same elevation as the surface of a nearby lake and the bottom of which coincides with bedrock resolved in companion seismic and ground-penetrating radar studies.

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Dietze, A., R. Gnirß, and U. Wiesmann. "Phosphorus removal with membrane filtration for surface water treatment." Water Science and Technology 46, no. 4-5 (August 1, 2002): 257–64. http://dx.doi.org/10.2166/wst.2002.0600.

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Surface waters are often burdened with inflows of low quality water, so that drinking-water production, swimming or ground water charging must be restricted. To ensure the long-term use of such surface water it is necessary to treat the influents or the water used for ground water charging. The current treatment process for phosphorus and turbidity removal is a process combination called floc filtration. By using this conventional method it is possible to reduce the dissolved ortho-phosphate and the turbidity (particulate phosphorus) as well as the amounts of algae and pathogenic organisms to very low concentrations. The high degree of reduction is only achieved by a relatively high dosage of chemicals. A comparison will be made between this process, which represents the state-of-the-art, and the combination of precipitation/coagulation with micro-/ultrafiltration in dead-end filtration mode.

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Renette, Cas, Kristoffer Aalstad, Juditha Aga, Robin Benjamin Zweigel, Bernd Etzelmüller, Karianne Staalesen Lilleøren, Ketil Isaksen, and Sebastian Westermann. "Simulating the effect of subsurface drainage on the thermal regime and ground ice in blocky terrain in Norway." Earth Surface Dynamics 11, no. 1 (January 27, 2023): 33–50. http://dx.doi.org/10.5194/esurf-11-33-2023.

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Abstract. Ground temperatures in coarse, blocky deposits such as mountain blockfields and rock glaciers have long been observed to be lower in comparison with other (sub)surface material. One of the reasons for this negative temperature anomaly is the lower soil moisture content in blocky terrain, which decreases the duration of the zero curtain in autumn. Here we used the CryoGrid community model to simulate the effect of drainage on the ground thermal regime and ground ice in blocky terrain permafrost at two sites in Norway. The model set-up is based on a one-dimensional model domain and features a surface energy balance, heat conduction and advection, as well as a bucket water scheme with adjustable lateral drainage. We used three idealized subsurface stratigraphies, blocks only, blocks with sediment and sediment only, which can be either drained (i.e. with strong lateral subsurface drainage) or undrained (i.e. without drainage), resulting in six scenarios. The main difference between the three stratigraphies is their ability to retain water against drainage: while the blocks only stratigraphy can only hold small amounts of water, much more water is retained within the sediment phase of the two other stratigraphies, which critically modifies the freeze–thaw behaviour. The simulation results show markedly lower ground temperatures in the blocks only, drained scenario compared to other scenarios, with a negative thermal anomaly of up to 2.2 ∘C. For this scenario, the model can in particular simulate the time evolution of ground ice, with build-up during and after snowmelt and spring and gradual lowering of the ice table in the course of the summer season. The thermal anomaly increases with larger amounts of snowfall, showing that well-drained blocky deposits are less sensitive to insulation by snow than other soils. We simulate stable permafrost conditions at the location of a rock glacier in northern Norway with a mean annual ground surface temperature of 2.0–2.5 ∘C in the blocks only, drained simulations. Finally, transient simulations since 1951 at the rock glacier site (starting with permafrost conditions for all stratigraphies) showed a complete loss of perennial ground ice in the upper 5 m of the ground in the blocks with sediment, drained run; a 1.6 m lowering of the ground ice table in the sediment only, drained run; and only 0.1 m lowering in the blocks only, drained run. The interplay between the subsurface water–ice balance and ground freezing/thawing driven by heat conduction can at least partly explain the occurrence of permafrost in coarse blocky terrain below the elevational limit of permafrost in non-blocky sediments. It is thus important to consider the subsurface water–ice balance in blocky terrain in future efforts in permafrost distribution mapping in mountainous areas. Furthermore, an accurate prediction of the evolution of the ground ice table in a future climate can have implications for slope stability, as well as water resources in arid environments.

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Idzelis, Raimondas Leopoldas, Kristina Greičiūtė, and Dainius Paliulis. "INVESTIGATION AND EVALUATION OF SURFACE WATER POLLUTION WITH HEAVY METALS AND OIL PRODUCTS IN KAIRIAI MILITARY GROUND TERRITORY." JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 14, no. 4 (December 31, 2006): 183–90. http://dx.doi.org/10.3846/16486897.2006.9636896.

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Water pollution with heavy metals, oil and its products is a very important environmental problem. Major part of chemical elements penetrating into the environment gets accumulated in the soil and bed sediment of water bodies. They may also migrate into surface, ground and underground water and spread at great distances. From here, they may enter again nutritional chains and poison living organisms. It is very important and necessary to investigate military territories and evaluate their environmental condition in order to identify the works of their cleaning and optimization of their environmental condition as well as their scope. However, not all the military territories in Lithuania have been sufficiently investigated so far, damage to the environment is not known. Therefore, investigation of such territories is of utmost importance, it is of scientific and environmental significance. This work is dedicated to the investigation and evaluation of surface water and bed sediment pollution with heavy metals and oil products in one of the biggest military grounds of Lithuania ‐ Kairiai Military Ground. Results of the investigation allowed answering the main questions about the most common pollutants, spreading in the environment because of military activities, to determine the level of pollution and most vulnerable territories.

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Waite, D. T., H. Sommerstad, R. Grover, L. Kerr, and N. D. Westcott. "Pesticides in ground water, surface water and spring runoff in a small saskatchewan watershed." Environmental Toxicology and Chemistry 11, no. 6 (June 1992): 741–48. http://dx.doi.org/10.1002/etc.5620110603.

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Donald, David B., Howard Block, and John Wood. "Role of ground water on hexachlorocyclohexane (lindane) detections in surface water in western Canada." Environmental Toxicology and Chemistry 16, no. 9 (September 1997): 1867–72. http://dx.doi.org/10.1002/etc.5620160915.

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Welch, Brian C., Robert W. Jacobel, and Steven A. Arcone. "First results from radar profiles collected along the US-ITASE traverse from Taylor Dome to South Pole (2006–2008)." Annals of Glaciology 50, no. 51 (2009): 35–41. http://dx.doi.org/10.3189/172756409789097496.

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AbstractThe 2006/07 and 2007/08 US-ITASE traverses from Taylor Dome to South Pole in East Antarctica provided opportunities to survey the subglacial and englacial environments using 3 MHz and 200MHz radar. We present first results of these new ground-based radar data. A prominent basal deformation layer indicates different ice-flow regimes for the northern and southern halves of the Byrd Glacier drainage. Buried dune stratigraphy that appears to be related to the megadunes towards the west occurs at depths of up to 1500 m. At least two new water-filled subglacial lakes were discovered, while two recently drained lakes identified from repeat ICESat surface elevation surveys appear to be devoid of water.

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Chudley, Thomas R., Poul Christoffersen, Samuel H. Doyle, Antonio Abellan, and Neal Snooke. "High-accuracy UAV photogrammetry of ice sheet dynamics with no ground control." Cryosphere 13, no. 3 (March 19, 2019): 955–68. http://dx.doi.org/10.5194/tc-13-955-2019.

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Abstract. Unmanned aerial vehicles (UAVs) and structure from motion with multi-view stereo (SfM–MVS) photogrammetry are increasingly common tools for geoscience applications, but final product accuracy can be significantly diminished in the absence of a dense and well-distributed network of ground control points (GCPs). This is problematic in inaccessible or hazardous field environments, including highly crevassed glaciers, where implementing suitable GCP networks would be logistically difficult if not impossible. To overcome this challenge, we present an alternative geolocation approach known as GNSS-supported aerial triangulation (GNSS-AT). Here, an on-board carrier-phase GNSS receiver is used to determine the location of photo acquisitions using kinematic differential carrier-phase positioning. The camera positions can be used as the geospatial input to the photogrammetry process. We describe the implementation of this method in a low-cost, custom-built UAV and apply the method in a glaciological setting at Store Glacier in western Greenland. We validate the technique at the calving front, achieving topographic uncertainties of ±0.12 m horizontally (∼1.1× the ground sampling distance) and ±0.14 m vertically (∼1.3× the ground sampling distance), when flying at an altitude of ∼ 450 m above ground level. This compares favourably with previous GCP-derived uncertainties in glacial environments and allows us to apply the SfM–MVS photogrammetry at an inland study site where ice flows at 2 m day−1 and stable ground control is not available. Here, we were able to produce, without the use of GCPs, the first UAV-derived velocity fields of an ice sheet interior. Given the growing use of UAVs and SfM–MVS in glaciology and the geosciences, GNSS-AT will be of interest to those wishing to use UAV photogrammetry to obtain high-precision measurements of topographic change in contexts where GCP collection is logistically constrained.

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Kurazumi, Yoshihito, Emi Kondo, Kenta Fukagawa, Yoshiaki Yamato, Kunihito Tobita, and Tadahiro Tsuchikawa. "Thermal environment mitigation effects in suburban area." E3S Web of Conferences 111 (2019): 06041. http://dx.doi.org/10.1051/e3sconf/201911106041.

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The purpose of this paper is to clarify the relationship between the physiological and psychological responses of the human body and the outdoor environment evaluation index ETFe (enhanced conductioncorrected modified effective temperature). The experiments were carried out in summer. For the measurements, observation points were selected with consideration for the condition of the ground surface such as bare ground where the surface is gravel or soil; paved ground such as concrete, asphalt or blocks; green areas covered in plants and water surfaces and with consideration for the condition of the sky factor due to buildings or trees. 19 observation points were chosen. Subjects were 38 healthy young. ETFe that was considered to report neither hot nor cold, thermally neutral sensation, was 30.6°C. ETFe that was considered to report neither comfortable nor uncomfortable comfort was 35.5°C. It was considered that the threshold for the human body with regards to thermal environment stimuli in an outdoor space is higher than the thermal environment stimuli in a summer indoor space.

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Li, Mengyun, Liang Hong, Jintao Guo, and Axing Zhu. "Automated Extraction of Lake Water Bodies in Complex Geographical Environments by Fusing Sentinel-1/2 Data." Water 14, no. 1 (December 23, 2021): 30. http://dx.doi.org/10.3390/w14010030.

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Lakes are an important component of global water resources. Lake water bodies extraction based on satellite remote sensing mainly utilizes optical or radar data. However, due to the influence of water quality, ground features with low reflectivity, and smooth surface features, it is still challenging to accurately extract water bodies in complex geographic environments. In this work, we proposed a lake water bodies extraction method by fusing Sentinel-1/2 data. Firstly, the proposed method analyzed the difference of the spectral polarization features between water and non-water in complex geographical environment. Then, the spectral polarization and water index were fused to multidimensional features by feature stacking. Finally, support vector machines are used to classify. Six typical lakes (including urban, mountains, and polluted and clean lakes) in China were used to verify the mapping accuracy. The results showed that extracting lake water bodies by fusing Sentinel-1/2 data had a better performance than using optical or radar data solely, all types of lakes achieved better extraction results, the overall accuracy of lake water extraction is improved by 3%, and the error of commission and omission is controlled within 6%. Comparative experiments indicate that combine radar polarization information with spectral information is helpful to improve the accuracy of different types of lakes extraction in complex geographical environment.

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Iqbal, R., S. Akimoto, K. Tokutake, T. Inoue, and H. Tachibana. "Water chemistry gradient in a degraded bog area." Water Science and Technology 53, no. 2 (January 1, 2006): 63–71. http://dx.doi.org/10.2166/wst.2006.039.

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Surface and ground water was sampled in a degraded bog area 36 times during 1993–2003 at Five representative points: point E (natural area with Sphagnum as the main vegetal cover), point W (boundary between the natural and degraded areas), point W' (area installed with vinyl sheeting), point WW (area where Sasa thrives), and point NC (area with naturally formed ditches). Analysis of variance (ANOVA) was conducted for parameters measured in surface water and ground water at 0.5, 1.0, 1.5, and 2.0 m depths. “Sampling point” (i.e. locations along the degradation gradient) accounted for most of the variation in surface and ground water chemistry. It accounted for 30–80% of the total variation in pH, electrical conductivity, ammonia, dissolved nitrogen, major cations (Na+, K+, Ca2+ , Mg2+ ), alkalinity and dissolved organic carbon. “Year” accounted for more variation in nitrate, nitrite, chloride, and sulfate than the sampling point did, but the variation in dissolved reactive phosphorus and dissolved phosphorus concentrations was not based on any of the calculated variables.

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Weisbrod, N., and M. I. Dragila. "Potential impact of convective fracture venting on salt-crust buildup and ground-water salinization in arid environments." Journal of Arid Environments 65, no. 3 (May 2006): 386–99. http://dx.doi.org/10.1016/j.jaridenv.2005.07.011.

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Fuchs, M., P. Kuhry, and G. Hugelius. "Low below-ground organic carbon storage in a subarctic Alpine permafrost environment." Cryosphere 9, no. 2 (March 2, 2015): 427–38. http://dx.doi.org/10.5194/tc-9-427-2015.

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Abstract. This study investigates the soil organic carbon (SOC) storage in Tarfala Valley, northern Sweden. Field inventories, upscaled based on land cover, show that this alpine permafrost environment does not store large amounts of SOC, with an estimate mean of 0.9 ± 0.2 kg C m−2 for the upper meter of soil. This is 1 to 2 orders of magnitude lower than what has been reported for lowland permafrost terrain. The SOC storage varies for different land cover classes and ranges from 0.05 kg C m−2 for stone-dominated to 8.4 kg C m−2 for grass-dominated areas. No signs of organic matter burial through cryoturbation or slope processes were found, and radiocarbon-dated SOC is generally of recent origin (<2000 cal yr BP). An inventory of permafrost distribution in Tarfala Valley, based on the bottom temperature of snow measurements and a logistic regression model, showed that at an altitude where permafrost is probable the SOC storage is very low. In the high-altitude permafrost zones (above 1500 m), soils store only ca. 0.1 kg C m−2. Under future climate warming, an upward shift of vegetation zones may lead to a net ecosystem C uptake from increased biomass and soil development. As a consequence, alpine permafrost environments could act as a net carbon sink in the future, as there is no loss of older or deeper SOC from thawing permafrost.

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Fediuk, Annika, Dennis Wilken, Martin Thorwart, Tina Wunderlich, Ercan Erkul, and Wolfgang Rabbel. "The Applicability of an Inverse Schlumberger Array for Near-Surface Targets in Shallow Water Environments." Remote Sensing 12, no. 13 (July 3, 2020): 2132. http://dx.doi.org/10.3390/rs12132132.

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We investigate the applicability of offshore geoelectrical profiling in the littoral zone, e.g., for archaeological prospection, sediment classification and investigations on coastal ground water upwelling. We performed field measurements with a 20 m long multi-electrode streamer in inverse Schlumberger configuration, which we used to statistically evaluate measurement uncertainty and the reproducibility of offshore electric resistivity tomography. We compared floating and submerged electrodes, as well as stationary and towed measurements. We found out that apparent resistivity values can be determined with an accuracy of 1% to 5% (1σ) depending on the measurement setup under field conditions. Based on these values and focusing on typical meter-scale targets, we used synthetic resistivity models to theoretically investigate the tomographic resolution and depth penetration achievable near-beach underneath a column of brackish water of about 1 m depth. From the analysis, we conclude that offshore geoelectric sounding allows the mapping of archaeological stone settings. The material differentiation of low-porosity rock masses < 15% is critical. Submerged wooden objects show a significant resistivity contrast to sand and rocks. Distinguishing brine-saturated sandy sediments from cohesive silty-clayey sediments is difficult due to their equal or reversed resistivity contrasts. Submarine freshwater discharges in sandy aquifers can be localized well, though difficulties may occur if the seafloor encounters massive low-porosity rock masses. As to the measurement setups, submerged and floating electrodes differ in their spatial resolution. Whereas stone settings of 0.5 to 1 m can still be located with submerged electrodes within the uppermost 4 m underneath the seafloor, they have to be >2 m if floating electrodes are used. Therefore, we recommend using submerged electrodes, especially in archaeological prospection. Littoral geological and hydrogeological mapping is also feasible with floating electrodes in a more time-saving way.

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Roy, Alexandre, Alain Royer, Olivier St-Jean-Rondeau, Benoit Montpetit, Ghislain Picard, Alex Mavrovic, Nicolas Marchand, and Alexandre Langlois. "Microwave snow emission modeling uncertainties in boreal and subarctic environments." Cryosphere 10, no. 2 (March 16, 2016): 623–38. http://dx.doi.org/10.5194/tc-10-623-2016.

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Abstract. This study aims to better understand and quantify the uncertainties in microwave snow emission models using the Dense Media Radiative Theory Multi-Layer model (DMRT-ML) with in situ measurements of snow properties. We use surface-based radiometric measurements at 10.67, 19 and 37 GHz in boreal forest and subarctic environments and a new in situ data set of measurements of snow properties (profiles of density, snow grain size and temperature, soil characterization and ice lens detection) acquired in the James Bay and Umiujaq regions of Northern Québec, Canada. A snow excavation experiment – where snow was removed from the ground to measure the microwave emission of bare frozen ground – shows that small-scale spatial variability (less than 1 km) in the emission of frozen soil is small. Hence, in our case of boreal organic soil, variability in the emission of frozen soil has a small effect on snow-covered brightness temperature (TB). Grain size and density measurement errors can explain the errors at 37 GHz, while the sensitivity of TB at 19 GHz to snow increases during the winter because of the snow grain growth that leads to scattering. Furthermore, the inclusion of observed ice lenses in DMRT-ML leads to significant improvements in the simulations at horizontal polarization (H-pol) for the three frequencies (up to 20 K of root mean square error). However, representation of the spatial variability of TB remains poor at 10.67 and 19 GHz at H-pol given the spatial variability of ice lens characteristics and the difficulty in simulating snowpack stratigraphy related to the snow crust. The results also show that, in our study with the given forest characteristics, forest emission reflected by the snow-covered surface can increase the TB up to 40 K. The forest contribution varies with vegetation characteristics and a relationship between the downwelling contribution of vegetation and the proportion of pixels occupied by vegetation (trees) in fisheye pictures was found. We perform a comprehensive analysis of the components that contribute to the snow-covered microwave signal, which will help to develop DMRT-ML and to improve the required field measurements. The analysis shows that a better consideration of ice lenses and snow crusts is essential to improve TB simulations in boreal forest and subarctic environments.

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Legeas, M., J. Carré, and Ph Mérot. "Effect of Wastewater Injection on Ground Water Quality." Water Science and Technology 25, no. 12 (June 1, 1992): 283–86. http://dx.doi.org/10.2166/wst.1992.0360.

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Effluents from the treatment plant of Saint Jean de Monts and Saint Hilaire de Riez have been injected into a confined ground water for twelve years. This ground water is connected with the sea. Effluent floats on the surface of the aquifer and it disperses by dilution at the freshwater/salt water interface. The aquifer acts as a direct overflow pipe. The injection of effluent has preserved the quality of waters in the coastal area and in the Breton Marsh.

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Vankeerberghen, Marc, Michel De Smet, and Christian Malekian. "Gauge-Strain-Controlled Air and PWR Fatigue Life Data for 304 Stainless Steel—Some Effects of Surface Finish and Hold Time." Metals 10, no. 9 (September 16, 2020): 1248. http://dx.doi.org/10.3390/met10091248.

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We performed environmental fatigue testing in simulated primary water reactor (PWR) primary water and reference fatigue testing in air in the framework of an international, collaborative project (INCEFA-PLUS), where the effects of mean strain and stress, hold time, strain amplitude and surface finish on fatigue life of austenitic stainless steels in light water reactor environments are being studied. Our fatigue lives obtained on machined specimens in air at 300 °C lie close to the NUREG/CR6909 mean air fatigue curve and are in line with INCEFA-PLUS air fatigue lives. Our environmental fatigue lives obtained in simulated PWR primary water at 300 °C lie relatively close to the NUREG/CR6909 mean fatigue curve; derived from the NUREG/CR6909 mean air fatigue curve and the applicable environmental correction factor (Fen). The PWR results show that (1) a polished surface finish has a slightly higher and a ground surface finish a slightly lower fatigue life than the NUREG/CR6909 prediction; (2) the ratio of polished to ground specimen life is ~1.37 at 300 °C and ~1.47 at 230 °C; (3) holds—at zero strain after a positive strain-rate—have a slightly detrimental effect on fatigue life. These results are in line with the INCEFA-PLUS PWR fatigue lives. A novel gauge-strain extensometer was deployed in order to perform a true gauge-strain-controlled fatigue test in simulated PWR primary water.

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Journal articles on the topic 'Ground and surface water environments'

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