40 CFR 63.9942 - What definitions apply to this subpart?

Code of Federal Regulations, 2014 CFR

2014-07-01

... metal alloys from natural sources of magnesium chloride such as sea water or water from the Great Salt... gases exhausted from gas turbines. Wet scrubber means a device that contacts an exhaust gas with a...

40 CFR 63.9942 - What definitions apply to this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... metal alloys from natural sources of magnesium chloride such as sea water or water from the Great Salt... gases exhausted from gas turbines. Wet scrubber means a device that contacts an exhaust gas with a...

40 CFR 63.9942 - What definitions apply to this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... metal alloys from natural sources of magnesium chloride such as sea water or water from the Great Salt... gases exhausted from gas turbines. Wet scrubber means a device that contacts an exhaust gas with a...

40 CFR 63.9942 - What definitions apply to this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... metal alloys from natural sources of magnesium chloride such as sea water or water from the Great Salt... gases exhausted from gas turbines. Wet scrubber means a device that contacts an exhaust gas with a...

40 CFR 63.9942 - What definitions apply to this subpart?

Code of Federal Regulations, 2013 CFR

2013-07-01

... metal alloys from natural sources of magnesium chloride such as sea water or water from the Great Salt... gases exhausted from gas turbines. Wet scrubber means a device that contacts an exhaust gas with a...

METHOD DEVELOPMENT FOR THE DETERMINATION OF PERFLUORINATED ORGANIC COMPOUNDS ( PFCS ) IN SURFACE WATER

EPA Science Inventory

The method for the determination of perfluorinated organic compounds (PFCs) in surface water has been developed and applied to natural water. The method shows an adequate sensitivity, precision and accuracy for ten kinds of target compounds. These PFCs were found in most samples...

Decision-making under surprise and uncertainty: Arsenic contamination of water supplies

NASA Astrophysics Data System (ADS)

Randhir, Timothy O.; Mozumder, Pallab; Halim, Nafisa

2018-05-01

With ignorance and potential surprise dominating decision making in water resources, a framework for dealing with such uncertainty is a critical need in hydrology. We operationalize the 'potential surprise' criterion proposed by Shackle, Vickers, and Katzner (SVK) to derive decision rules to manage water resources under uncertainty and ignorance. We apply this framework to managing water supply systems in Bangladesh that face severe, naturally occurring arsenic contamination. The uncertainty involved with arsenic in water supplies makes the application of conventional analysis of decision-making ineffective. Given the uncertainty and surprise involved in such cases, we find that optimal decisions tend to favor actions that avoid irreversible outcomes instead of conventional cost-effective actions. We observe that a diversification of the water supply system also emerges as a robust strategy to avert unintended outcomes of water contamination. Shallow wells had a slight higher optimal level (36%) compare to deep wells and surface treatment which had allocation levels of roughly 32% under each. The approach can be applied in a variety of other cases that involve decision making under uncertainty and surprise, a frequent situation in natural resources management.

MONITORED NATURAL ATTENUATION FOR INORGANIC CONTAMINANT REMEDIATION IN GROUNDWATER

EPA Science Inventory

Monitored natural attenuation (MNA) has been applied as a knowledge-based remediation technology for organic contaminants in ground water. Development of a site-specific assessment of biotic and abiotic processes that lead to organic contaminant degradation provides the technica...

Sewage disinfection towards protection of drinking water resources.

PubMed

Kolch, A

2000-01-01

Wastewater applied in agriculture for irrigation could replace the use of natural drinking-water resources. With respect to high concentrations of human pathogens wastewater has to be disinfected prior to use. This paper introduces disinfection methods with emphasis on UV irradiation.

Water Relations, Gas Exchange, and Nutrient Response to a Long Term Constant Water Deficit

NASA Technical Reports Server (NTRS)

Berry, Wade L.; Goldstein, Guillermo; Dreschel, Thomas W.; Wheeler, Raymond M.; Sager, John C.; Knott, William M.

1992-01-01

Wheat plants (Triticum aestivum) were grown for 43 days in a micro-porous tube nutrient delivery system. Roots were unable to penetrate the microporous tube, but grew on the surface and maintained capillary contact with the nutrient solution on the inside of the tube through the 5-microns pores of the porous tube. Water potential in the system was controlled at -0.4, -0.8, and -3.0 kPa by adjusting the applied pressure (hydrostatic head) to the nutrient solution flowing through the microporous tubes. A relatively small decrease in applied water potential from -0.4 to -3.0 kPa resulted in a 34% reduction of shoot growth but only a moderate reduction in the mid-day leaf water potential from - 1.3 to - 1.7 MPa. Carbon dioxide assimilation decreased and water use efficiency increased with the more negative applied water Potentials, while intercellular C02 concentration remained constant. The physiological responses observed in this study in response to small constant differences in applied water potentials were much greater than expected from either the applied water potential or the observed plant water potential. Even though the micro-porous tube may not represent natural conditions and could possibly introduce morphological and physiological artifacts , it enables a high degree of control of water potential that facilitates the investigation of many aspects of water relations not practical with other experimental systems.

Environmental Perceptions of Surface Water Quality and Management: a tool to strengthen public participation in the search for solutions to the imbalance of water in nature. A study applied in Chiapas's Río Fogótico Microbasin

NASA Astrophysics Data System (ADS)

Benez, M. C.; Kauffer Michel, E. F.

2013-05-01

The study of environmental perceptions can expose interstings aspects involved in imbalance of water in nature. The main objective of this study was to assess the perceptions of quality and management of surface water in the Fogótico River microbasin in San Cristóbal de Las Casas, Chiapas, from the perspective of differents social groups. Secondary objectives consisted in analyzing the differences of perception according to social groups and considering the potential contribution of perception studies for watershed management.; t;

Estimating Natural Recharge in a Desert Environment Facing Increasing Ground-Water Demands

NASA Astrophysics Data System (ADS)

Nishikawa, T.; Izbicki, J. A.; Hevesi, J. A.; Martin, P.

2004-12-01

Ground water historically has been the sole source of water supply for the community of Joshua Tree in the Joshua Tree ground-water subbasin of the Morongo ground-water basin in the southern Mojave Desert. Joshua Basin Water District (JBWD) supplies water to the community from the underlying Joshua Tree ground-water subbasin, and ground-water withdrawals averaging about 960 acre-ft/yr have resulted in as much as 35 ft of drawdown. As growth continues in the desert, ground-water resources may need to be supplemented using imported water. To help meet future demands, JBWD plans to construct production wells in the adjacent Copper Mountain ground-water subbasin. To manage the ground-water resources and to identify future mitigating measures, a thorough understanding of the ground-water system is needed. To this end, field and numerical techniques were applied to determine the distribution and quantity of natural recharge. Field techniques included the installation of instrumented boreholes in selected washes and at a nearby control site. Numerical techniques included the use of a distributed-parameter watershed model and a ground-water flow model. The results from the field techniques indicated that as much as 70 acre-ft/yr of water infiltrated downward through the two principal washes during the study period (2001-3). The results from the watershed model indicated that the average annual recharge in the ground-water subbasins is about 160 acre-ft/yr. The results from the calibrated ground-water flow model indicated that the average annual recharge for the same area is about 125 acre-ft/yr. Although the field and numerical techniques were applied to different scales (local vs. large), all indicate that natural recharge in the Joshua Tree area is very limited; therefore, careful management of the limited ground-water resources is needed. Moreover, the calibrated model can now be used to estimate the effects of different water-management strategies on the ground-water subbasins.

Water, frost, and frost resistance of natural and artificial building stones

USGS Publications Warehouse

Breyer, H.; Britt, S. H.

1953-01-01

The worst enemy of construction engineering and of construction material is uncontrollable water, whether it be ground-, seepage-, rainwater, water of condensation, or melting snow and ice, exerting objectionable pressure upon tracks and roads. this applies as well to structures above the ground as to bridge piers and foundations, road construction, earthwork, etc. 

Natural Pathogen Control Chemistry to Replace Toxic Treatment of Microbes and Biofilm in Cooling Towers

PubMed Central

Brouse, Lon; Brouse, Richard; Brouse, Daniel

2017-01-01

Application of toxic antibacterial agents is considered necessary to control prevalent fresh water microorganisms that grow in evaporative cooling water systems, but can adversely affect the environment and human health. However, natural antibacterial water chemistry has been applied in industrial cooling water systems for over 10 years to inhibit microorganisms with excellent results. The water chemistry method concentrates natural minerals in highly-softened water to produce elevated pH and dissolved solids, while maintaining low calcium and magnesium content. The method provides further benefits in water conservation, and generates a small volume of non-toxic natural salt concentrate for cost efficient separation and disposal if required. This report describes the antimicrobial effects of these chemistry modifications in the cooling water environment and the resultant collective inhibition of microbes, biofilm, and pathogen growth. This article also presents a novel perspective of parasitic microbiome functional relationships, including “Trojan Protozoans” and biofilms, and the function of polyvalent metal ions in the formation and inhibition of biofilms. Reducing global dependence on toxic antibacterial agents discharged to the environment is an emerging concern due to their impact on the natural microbiome, plants, animals and humans. Concurrently, scientists have concluded that discharge of antibacterial agents plays a key role in development of pathogen resistance to antimicrobials as well as antibiotics. Use of natural antibacterial chemistry can play a key role in managing the cooling water environment in a more ecologically sustainable manner. PMID:28420074

An Approach for Evaluating the Progress of Natural Attenuation in Groundwater (Web Conference)

EPA Science Inventory

Monitored Natural Attenuation (MNA) is widely applied to ground water contamination at hazardous waste sites. Under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), MNA is considered to be a remedy like any other remedy. When MNA has been select...

Use of naturally growing aquatic plants for wastewater purification.

PubMed

Zimmels, Y; Kirzhner, F; Roitman, S

2004-01-01

This paper examines potential uses of naturally growing aquatic plants for wastewater purification. These plants enhance the removal of pollutants by consuming part of them in the form of plant nutrients. This applies to urban and agricultural wastewater, in particular, where treatment units of different sizes can be applied at the pollution source. The effectiveness of wastewater purification by different plants was tested on laboratory and pilot scales. The growth rate of the plants was related to the wastewater content in the water. Batch and semicontinuous experiments verified that the plants are capable of decreasing all tested indicators for water quality to levels that permit the use of the purified water for irrigation. This applies to biochemical oxygen demand (BOD), chemical oxygen demand, total suspended solids. pH, and turbidity. In specific cases, the turbidity reached the level of drinking water. Comparison of BOD concentrations with typical levels in water treatment facilities across the country indicates the effectiveness of water purification with plants. A major effect of treatment with plants was elimination of the disturbing smell from the wastewater. It is shown that mixtures of wastewater and polluted water from the Kishon River are amenable in varying degrees to treatment by the plants. The higher the wastewater content in the mixture, the more effective the treatment by the plants. In this context, a scheme for rehabilitation and restoration of the Kishon River is presented and technical and economical aspects of the purification technology are considered.

Methodology for applying monitored natural attenuation to petroleum hydrocarbon-contaminated ground-water systems with examples from South Carolina

USGS Publications Warehouse

Chapelle, Frank H.; Robertson, John F.; Landmeyer, James E.; Bradley, Paul M.

2000-01-01

These two sites illustrate how the efficiency of natural attenuation processes acting on petroleum hydrocarbons can be systematically evaluated using hydrologic, geochemical, and microbiologic methods.  These methods, in turn, can be used to assess the role that the natural attenuation of petroleum hydrocarbons can play in achieving overall site remediation.

RECYCLING OF WATER TREATMENT PLANT SLUDGE VIA LAND APPLICATION: ASSESSMENT OF RISK

EPA Science Inventory

Water treatment sludges (WTS) offer potential benefits when applied to soil and recycling of the waste stream via land application has been proposed as a management option. Recycling of WTS to the land helps conserve landfill disposal capacity and natural resources, but potential...

Bathing in carbon dioxide-enriched water alters protein expression in keratinocytes of skin tissue in rats

NASA Astrophysics Data System (ADS)

Kälsch, Julia; Pott, Leona L.; Takeda, Atsushi; Kumamoto, Hideo; Möllmann, Dorothe; Canbay, Ali; Sitek, Barbara; Baba, Hideo A.

2017-04-01

Beneficial effects of balneotherapy using naturally occurring carbonated water (CO2 enriched) have been known since the Middle Ages. Although this therapy is clinically applied for peripheral artery disease and skin disorder, the underlying mechanisms are not fully elucidated.

Using stable isotopes of water and strontium to investigate the hydrology of a natural and a constructed wetland

USGS Publications Warehouse

Hunt, R.J.; Bullen, T.D.; Krabbenhoft, D.P.; Kendall, C.

1998-01-01

Wetlands cannot exist without water, but wetland hydrology is difficult to characterize. As a result, compensatory wetland mitigation often only assumes the proper hydrology has been created. In this study, water sources and mass transfer processes in a natural and constructed wetland complex were investigated using isotopes of water and strontium. Water isotope profiles in the saturated zone revealed that the natural wetland and one site in the constructed wetland were primarily fed by ground water; profiles in another constructed wetland site showed recent rain was the predominant source of water in the root zone. Water isotopes in the capillary fringe indicated that the residence time for rain is less in the natural wetland than in the constructed wetland, thus transpiration (an important water sink) was greater in the natural wetland. Strontium isotopes showed a systematic difference between the natural and constructed wetlands that we attribute to the presence or absence of peat. In the peat-rich natural wetland, ??87Sr in the pore water increased along the flowline due to preferential weathering of minerals containing radiogenic Sr in response to elevated Fe concentrations in the water. In the constructed wetland, where peat thickness was thin and Fe concentrations in water were negligible, ??87Sr did not increase along the flowline. The source of the peat (on-site or off-site derived) applied in the constructed wetland controlled the ??87Sr at the top of the profile, but the effects were restricted by strong cation exchange in the underlying fluvial sediments. Based on the results of this study, neither constructed wetland site duplicated the water source and weathering environment of the adjoining natural wetland. Moreover, stable isotopes were shown to be effective tools for investigating wetlands and gaining insight not easily obtained using non-isotopic techniques. These tools have potential widespread application to wetlands that have distinct isotopic endmember sources.

Selective Determination of Lipid Hydroperoxides in Natural Waters Using a Fluorescent Probe

NASA Astrophysics Data System (ADS)

Sunday, M. O.; Sakugawa, H.

2016-12-01

The presence of various lipids in natural waters and the availability of conditions needed for their oxidation to lipid hydroperoxides (LHPs) suggest that LHPs may be part of the hydroperoxide mix in natural waters. While other hydroperoxides, including H2O2, methyl hydroperoxide (MHP) and ethyl hydroperoxide (EHP) etc. have been investigated, there is no information on LHPs in natural waters. In this study, we report the presence of LHPs in natural waters. Firstly, a method selective to LHPs determination was developed using 2-(4-diphenylphosphanyl-phenyl)-9-(3,6,9,12-tetraoxatridecyl)-anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10-tetraone, Liperfluo, as a fluorescent probe. A flow injector analysis equipped with fluorescence detector was used for fluorescence measurement of Liperfluo-Ox formed from the reaction between Liperfluo and LHP. Under the optimized conditions, the reaction of Liperfluo with LHP in MilliQ and river water had a linear range of 0-500 nM LHP. The method detection limit was 10.1 nM and 7.3 nM in riverwater and MilliQ respectively. The coefficient of variation for five replicate measurements each for 100 nM and 500 nM LHP was ≤ 3.8%. The probe and the conditions used in this study showed high selectivity for LHP over other natural water hydroperoxides, including H2O2, MHP and EHP. The method was applied in the quantification of LHPs in water from the Kurose River (Japan). The concentration ranged from below detection limit to 98 nM (ave. 37.2 nM; n=12). Increase in H2O2 formation upon irradiation of LHP-spiked riverwater in a solar simulator suggests H2O2 formation as one of the possible sinks of LHPs in natural waters. For the first time, this study reveals that LHPs are part of the hydroperoxide mix in natural waters and provides insight on its fate in natural waters.

Sustainable Drainage, Green Infrastructure or Natural Flood Management - which should you choose?

NASA Astrophysics Data System (ADS)

Wingfield, Thea; Potter, Karen; Jones, Gareth; Spees, Jack; Macdonald, Neil

2016-04-01

River catchments as management units are more effective than administrative boundaries to integrate and coordinate efforts of organisations that utilise and manage water, soil and habitat quality. The UK government announced a pilot integrated water management initiative called, 'The Catchment Based Approach', on World Water Day 2011. After successful trials the scheme was extended to all river catchments in England during the summer of 2013. This policy has been designed to improve the collaboration, partnership and coordination of organisations involved in water and land management through locally led partnership groups. The lead organisations are all charitable bodies with significantly varying levels of experience of stormwater management; a key component of integrated water management and of great concern to communities at risk. These partnerships have implemented a number of Nature Based Solutions, but these have been presented in different ways by the different groups. In the UK there are three terms commonly used to describe Nature Based Solutions for managing the drainage of stormwater: Sustainable Drainage (SuDS), Green Infrastructure (GI) and Natural Flood Management (NFM). The definitions of each refers to the replication of natural hydrological processes in order to slow the flow of water through the landscape. But, there has been some concerns as to which of these nature based terms should be applied and why they appear to be used interchangeably. This study demonstrates that, despite the definitions of these three terms being almost identical, in practice they are not the same and should not be used interchangeably. The terms were developed by different professional groups in response to their own objectives and histories. The hydrological processes used to manage storm-water may be the same and the suggested interventions may show a degree of convergence. Yet, they operate at different scales, both geographically and organisationally. The different professional disciplines have their own ideologies and work to distinct governing regulations which manage and perceive operational risk in varying ways. All of these factors lead to storm-water nature based solutions not just being applied differently within a catchment but viewed and understood differently by organisations that are working in partnership. The catchment partnerships will be better equipped to incorporate or employ nature based storm water management in the UK through this research. By understanding the factors and agents behind the development of SuDS, GI and NFM and providing ways in which to visualise and communicate this at a catchment level it is hoped to reduce some of the barriers to their practical implementation.

43 CFR 3275.12 - What environmental and safety requirements apply to facility operations?

Code of Federal Regulations, 2011 CFR

2011-10-01

... that: (1) Protects the quality of surface and subsurface waters, air, and other natural resources, including wildlife, soil, vegetation, and natural history; (2) Prevents unnecessary or undue degradation of the lands; (3) Protects the quality of cultural, scenic, and recreational resources; (4) Accommodates...

Modified zirconium-eriochrome cyanine R determination of fluoride

USGS Publications Warehouse

Thatcher, L.L.

1957-01-01

The Eriochrome Cyanine R method for determining fluoride in natural water has been modified to provide a single, stable reagent solution, eliminate interference from oxidizing agents, extend the concentration range to 3 p.p.m., and extend the phosphate tolerance. Temperature effect was minimized; sulfate error was eliminated by precipitation. The procedure is sufficiently tolerant to interferences found in natural and polluted waters to permit the elimination of prior distillation for most samples. The method has been applied to 500 samples.

Characterisation of hydrogeological connections in a lowland karst network using time series analysis of water levels in ephemeral groundwater-fed lakes (turloughs)

NASA Astrophysics Data System (ADS)

Gill, L. W.; Naughton, O.; Johnston, P. M.; Basu, B.; Ghosh, B.

2013-08-01

This research has used continuous water level measurements five groundwater-fed lakes (or turloughs) in a linked lowland karst network of south Galway in Ireland over a 3 year period in order to elucidate the hydrogeological controls and conduit configurations forming the flooded karstic hydraulic system beneath the ground. The main spring outflow from this network discharges below mean sea level making it difficult to determine the hydraulic nature of the network using traditional rainfall-spring flow cross analysis, as has been done in many other studies on karst systems. However, the localised groundwater-surface water interactions (the turloughs) in this flooded lowland karst system can yield information about the nature of the hydraulic connections beneath the ground. Various different analytical techniques have been applied to the fluctuating turlough water level time series data in order to determine the nature of the linkage between them as well as hydraulic pipe configurations at key points in order to improve the conceptual model of the overall karst network. Initially, simple cross correlations between the different turlough water levels were carried out applying different time lags. Frequency analysis of the signals was then carried out using Fast Fourier transform analysis and then both discrete and continuous wavelet analyses have been applied to the data sets to characterise these inherently non-stationary time-series of fluctuating water levels. The analysis has indicated which turloughs are on the main line conduit system and which are somewhat off-line, the relative size of the main conduit in the network including evidence of localised constrictions, as well as clearly showing the tidal influence on the water levels in the three lower turloughs at shallow depths ∼8 km from the main spring outfall at the sea. It has also indicated that the timing of high rainfall events coincident with maximum spring tide levels may promote more consistent, long duration flooding of the turloughs throughout the winter.

Validation of an SPME method, using PDMS, PA, PDMS-DVB, and CW-DVB SPME fiber coatings, for analysis of organophosphorus insecticides in natural waters.

PubMed

Lambropoulou, D A; Sakkas, V A; Albanis, T A

2002-11-01

Solid-phase microextraction (SPME) has been optimized and applied to the determination of the organophosphorus insecticides diazinon, dichlofenthion, parathion methyl, malathion, fenitrothion, fenthion, parathion ethyl, bromophos methyl, bromophos ethyl, and ethion in natural waters. Four types of SPME fiber coated with different stationary phases (PDMS, PA, PDMS-DVB, and CW-DVB) were used to examine their extraction efficiencies for the compounds tested. Conditions that might affect the SPME procedure, such as extraction time and salt content, were investigated to determine the analytical performance of these fiber coatings for organophosphorus insecticides. The optimized procedure was applied to natural waters - tap, sea, river, and lake water - spiked in the concentration range 0.5 to 50 micro g L(-1) to obtain the analytical characteristics. Recoveries were relatively high - >80% for all types of aqueous sample matrix - and the calibration plots were reproducible and linear (R(2)>0.982) for all analytes with all the fibers tested. The limits of detection ranged from 2 to 90 ng L(-1), depending on the detector and the compound investigated, with relative standard deviations in the range 3-15% at all the concentration levels tested. The SPME partition coefficients (K(f)) of the organophosphorus insecticides were calculated experimentally for all the polymer coatings. The effect of organic matter such as humic acids on extraction efficiency was also studied. The analytical performance of the SPME procedure using all the fibers in the tested natural waters proved effective for the compounds.

Effect of Electric Field on Gas Hydrate Nucleation Kinetics: Evidence for the Enhanced Kinetics of Hydrate Nucleation by Negatively Charged Clay Surfaces.

PubMed

Park, Taehyung; Kwon, Tae-Hyuk

2018-03-06

Natural gas hydrates are found widely in oceanic clay-rich sediments, where clay-water interactions have a profound effect on the formation behavior of gas hydrates. However, it remains unclear why and how natural gas hydrates are formed in clay-rich sediments in spite of factors that limit gas hydrate formation, such as small pore size and high salinity. Herein, we show that polarized water molecules on clay surfaces clearly promote gas hydrate nucleation kinetics. When water molecules were polarized with an electric field of 10 4 V/m, gas hydrate nucleation occurred significantly faster with an induction time reduced by 5.8 times. Further, the presence of strongly polarized water layers at the water-gas interface hindered gas uptake and thus hydrate formation, when the electric field was applied prior to gas dissolution. Our findings expand our understanding of the formation habits of naturally occurring gas hydrates in clay-rich sedimentary deposits and provide insights into gas production from natural hydrate deposits.

Determination of barium in natural waters by ICP-OES technique. Part II: Assessment of human exposure to barium in bottled mineral and spring waters produced in Poland.

PubMed

Garboś, Sławomir; Swiecicka, Dorota

2013-01-01

A method of the classification of natural mineral and spring waters and maximum admissible concentration (MAC) levels of metals present in such types of waters are regulated by Commission Directive 2003/40/EC, Directive 2009/54/EC of the European Parliament and of the Council and Ordinance of Minister of Health of 30 March 2011 on the natural mineral waters, spring waters and potable waters. MAC of barium in natural mineral and spring waters was set at 1.0 mg/l, while World Health Organization determined the Ba guideline value in water intended for human consumption at the level of 0.7 mg/l. The aims of the study were: the determination of barium in natural mineral and spring waters (carbonated, non-carbonated and medium-carbonated waters) produced and bottled on the area of Poland, and assessment of human exposure to this metal presents in the above-mentioned types of waters. The study concerning barium determinations in 23 types of bottled natural mineral waters and 15 types of bottled spring waters (bought in Polish retail outlets) was conducted in 2010. The analyses were performed by validated method of determination of barium in water based on inductively coupled plasma optical emission spectrometry, using modern internal quality control scheme. Concentrations of barium determined in natural mineral and spring waters were in the ranges from 0.0136 mg/l to 1.12 mg/l and from 0.0044 mg/l to 0.43 mg/l, respectively. Only in the single case of natural mineral water the concentration of barium (1.12 mg/l), exceeded above-mentioned MAC for this metal, which is obligatory in Poland and the European Union - 1.0 mg/l. The long-term monitoring of barium concentration in another natural mineral water (2006 - 2010), in which incidental exceeding MAC was observed in 2006, was conducted. All measured barium concentrations in this water were lower than 1.0 mg/l and therefore, it is possible to state that the proper method of mixing waters taken from six independent groundwater intakes applied during production is actually used. The estimated Hazard Quotient indices were in the ranges: 0.0019 - 0.16 (natural mineral waters) and 0.00063 - 0.061 (natural spring waters), respectively. The natural mineral waters are usually characterized by higher Ba concentrations than those observed in the cases of natural spring waters. The presence of a high concentration of HCO3- in such types of natural waters ensures the existence of Ba2+ in solution as Ba(HCO3)2, which is a highly soluble salt. Taking into account the concentrations of barium determined in above-mentioned waters and the available toxicological data for this metal no long-term risk for human health could be expected (estimated Hazard Quotient indices < or = 0.16).

Water conservation implications for decarbonizing non-electric energy supply: A hybrid life-cycle analysis.

PubMed

Liu, Shiyuan; Wang, Can; Shi, Lei; Cai, Wenjia; Zhang, Lixiao

2018-08-01

Low-carbon transition in the non-electric energy sector, which includes transport and heating energy, is necessary for achieving the 2 °C target. Meanwhile, as non-electric energy accounts for over 60% of total water consumption in the energy supply sector, it is vital to understand future water trends in the context of decarbonization. However, few studies have focused on life-cycle water impacts for non-electric energy; besides, applying conventional LCA methodology to assess non-electric energy has limitations. In this paper, a Multi-Regional Hybrid Life-Cycle Assessment (MRHLCA) model is built to assess total CO 2 emissions and water consumption of 6 non-electric energy technologies - transport energy from biofuel and gasoline, heat supply from natural gas, biogas, coal, and residual biomass, within 7 major emitting economies. We find that a shift to natural gas and residual biomass heating can help economies reduce 14-65% CO 2 and save more than 21% water. However, developed and developing economies should take differentiated technical strategies. Then we apply scenarios from IMAGE model to demonstrate that if economies take cost-effective 2 °C pathways, the water conservation synergy for the whole energy supply sector, including electricity, can also be achieved. Copyright © 2018 Elsevier Ltd. All rights reserved.

Optimisation of the storage of natural freshwaters before organotin speciation.

PubMed

Bancon-Montigny, C; Lespes, G; Potin-Gautier, M

2001-01-01

The speciation of organotin compounds is essential due to the species-dependent toxicity, especially in natural waters. Precautions have to be taken during sampling and storage of waters in order to prevent degradations and losses. Experimental design methodology has been used to study the conditions of stability of organotins after water sampling in rivers. The modelling of results allows the determination of optimal conditions of preservation. After acidification at pH = 4 with nitric acid, the storage in polyethylene containers at 4 degrees C in the dark is suitable to preserve the most degradable trisubstituted (butyl- and phenyl-) species over 1 month. These conditions of sampling and storage are applied to two different freshwaters. The rate of species decomposition appears to be only dependent on the water nature, whatever the organotin concentrations in the sample. Speciation could be so preserved between 1 and 3 months.

Electrochemical advanced oxidation processes as decentralized water treatment technologies to remediate domestic washing machine effluents.

PubMed

Dos Santos, Alexsandro Jhones; Costa, Emily Cintia Tossi de Araújo; da Silva, Djalma Ribeiro; Garcia-Segura, Sergi; Martínez-Huitle, Carlos Alberto

2018-03-01

Water scarcity is one of the major concerns worldwide. In order to secure this appreciated natural resource, management and development of water treatment technologies are mandatory. One feasible alternative is the consideration of water recycling/reuse at the household scale. Here, the treatment of actual washing machine effluent by electrochemical advanced oxidation processes was considered. Electrochemical oxidation and electro-Fenton technologies can be applied as decentralized small-scale water treatment devices. Therefore, efficient decolorization and total organic abatement have been followed. The results demonstrate the promising performance of solar photoelectro-Fenton process, where complete color and organic removal was attained after 240 min of treatment under optimum conditions by applying a current density of 66.6 mA cm -2 . Thus, electrochemical technologies emerge as promising water-sustainable approaches.

Liquid chromatography with diode array detection and multivariate curve resolution for the selective and sensitive quantification of estrogens in natural waters.

PubMed

Pérez, Rocío L; Escandar, Graciela M

2014-07-04

Following the green analytical chemistry principles, an efficient strategy involving second-order data provided by liquid chromatography (LC) with diode array detection (DAD) was applied for the simultaneous determination of estriol, 17β-estradiol, 17α-ethinylestradiol and estrone in natural water samples. After a simple pre-concentration step, LC-DAD matrix data were rapidly obtained (in less than 5 min) with a chromatographic system operating isocratically. Applying a second-order calibration algorithm based on multivariate curve resolution with alternating least-squares (MCR-ALS), successful resolution was achieved in the presence of sample constituents that strongly coelute with the analytes. The flexibility of this multivariate model allowed the quantification of the four estrogens in tap, mineral, underground and river water samples. Limits of detection in the range between 3 and 13 ng L(-1), and relative prediction errors from 2 to 11% were achieved. Copyright © 2014 Elsevier B.V. All rights reserved.

Total and Viable Legionella pneumophila Cells in Hot and Natural Waters as Measured by Immunofluorescence-Based Assays and Solid-Phase Cytometry ▿†

PubMed Central

Parthuisot, N.; Binet, M.; Touron-Bodilis, A.; Pougnard, C.; Lebaron, P.; Baudart, J.

2011-01-01

A new method was developed for the rapid and sensitive detection of viable Legionella pneumophila. The method combines specific immunofluorescence (IF) staining using monoclonal antibodies with a bacterial viability marker (ChemChrome V6 cellular esterase activity marker) by means of solid-phase cytometry (SPC). IF methods were applied to the detection and enumeration of both the total and viable L. pneumophila cells in water samples. The sensitivity of the IF methods coupled to SPC was 34 cells liter−1, and the reproducibility was good, with the coefficient of variation generally falling below 30%. IF methods were applied to the enumeration of total and viable L. pneumophila cells in 46 domestic hot water samples as well as in cooling tower water and natural water samples, such as thermal spring water and freshwater samples. Comparison with standard plate counts showed that (i) the total direct counts were always higher than the plate counts and (ii) the viable counts were higher than or close to the plate counts. With domestic hot waters, when the IF assay was combined with the viability test, SPC detected up to 3.4 × 103 viable but nonculturable L. pneumophila cells per liter. These direct IF methods could be a powerful tool for high-frequency monitoring of domestic hot waters or for investigating the occurrence of viable L. pneumophila in both man-made water systems and environmental water samples. PMID:21742913

Ground-water hydraulics - A summary of lectures presented by John G. Ferris at short courses conducted by the Ground Water Branch, part 1, Theory

USGS Publications Warehouse

Knowles, D.B.

1955-01-01

The objective of the Ground Water Branch is to evaluate the occurrence, availability, and quality of ground water.  The science of ground-water hydrology is applied toward attaining that goal.  Although many ground-water investigations are of a qualitative nature, quantitative studies are necessarily an integral component of the complete evaluation of occurrence and availability.  The worth of an aquifer as a fully developed source of water depends largely on two inherent characteristics: its ability to store, and its ability to transmit water.  Furthermore, quantitative knowledge of these characteristics facilitates measurement of hydrologic entities such as recharge, leakage, evapotranspiration, etc.  It is recognized that these two characteristics, referred to as the coefficients of storage and transmissibility, generally provide the very foundation on which quantitative studies are constructed.  Within the science of ground-water hydrology, ground-water hydraulics methods are applied to determine these constats from field data.

A settling curve modeling method for quantitative description of the dispersion stability of carbon nanotubes in aquatic environments.

PubMed

Zhou, Lixia; Zhu, Dunxue; Zhang, Shujuan; Pan, Bingcai

2015-03-01

Understanding the aggregation and deposition behavior of carbon nanotubes (CNTs) is of great significance in terms of their fate and transport in the environment. Attachment efficiency is a widely used index for well-dispersed CNT solutions. However, in natural waters, CNTs are usually heterogeneous in particle size. The attachment efficiency method is not applicable to such systems. Describing the dispersion stability of CNTs in natural aquatic systems is still a challenge. In this work, a settling curve modeling (SCM) method was developed for the description of the aggregation and deposition behavior of CNTs in aqueous solutions. The effects of water chemistry (natural organic matter, pH, and ionic strength) on the aggregation and deposition behavior of pristine and surface-functionalized multi-walled carbon nanotubes (MWCNTs) were systematically studied to evaluate the reliability of the SCM method. The results showed that, as compared to particle size and optical density, the centrifugal sedimentation rate constant (ks) from the settling curve profile is a practical, useful and reliable index for the description of heterogeneous CNT suspensions. The SCM method was successfully applied to MWCNT in three natural waters. The constituents in water, especially organic matter, determine the dispersion stability of MWCNTs in natural water bodies. Copyright © 2015. Published by Elsevier B.V.

Water Relations, Gas Exchange, and Nutrient Response to a Long Term Constant Water Deficit

NASA Technical Reports Server (NTRS)

Berry, Wade L.; Goldstein, Guillermo; Dreschel, Thomas W.; Wheeler, Raymond M.; Sager, John C.; Knott, William M.

1992-01-01

Wheat plants (Triticum aestivum) were grown for 43 days in a micro-porous tube nutrient delivery system. Roots were unable to penetrate the microporous tube, but grew on the surface and maintained capillary contact with the nutrient solution on the inside of the tube through the 5-micron pores of the porous tube. Water potential in the system was controlled at -0.4, -0.8, and -3.0 kPa by adjusting the applied pressure (hydrostatic head) to the nutrient solution flowing through the microporous tubes. A relatively small decrease in applied water potential from -0.4 to -3.0 kPa resulted in a 34% reduction of shoot growth but only a moderate reduction in the midday leaf water potential from -1.3 to -1.7 MPa. Carbon dioxide assimilation decreased and water use efficiency increased with the more negative applied water potentials, while intercellular CO2 concentration remained constant. This was associated with a decrease in stomatal conductance to water vapor from 1.90 to 0.98 mol/(sq m sec) and a decrease in total apparent hydraulic conductance from 47 to 12 (micro)mol/(sec MPa). Although the applied water potentials were in the -0.4 to -3.0 kPa range, the actual water potential perceived by the plant roots appeared to be in the range of -0.26 to -0.38 MPa as estimated by the leaf water potential of bagged plants. The amount of K, Ca, Mg, Zn, Cu, and B accumulated with each unit of transpired water increased as the applied water potential became less negative. The increase in accumulation ranged from 1.4-fold for K to 2.2-fold for B. The physiological responses observed in this study in response to small constant differences in applied water potentials were much greater than expected from either the applied water potential or the observed plant water potential. Even though the micro-porous tube may not represent natural conditions and could possibly introduce morphological and physiological artifacts, it enables a high degree of control of water potential that facilitates the investigation of many aspects of water relations not practical with other experimental systems.

Water. Shopware[R] Applied Biology/Chemistry. [CD-ROM].

ERIC Educational Resources Information Center

2000

This CD-ROM is part of a multimedia software and video collection for high school and vocational schools. Applied Biology/Chemistry is one of many series providing resources for science education. There are six individual titles in this series which include: (1) Natural Resources; (2) Air and Other Gases; (3) Nutrition; (4) Continuity of Life; (5)…

An environmental forensic procedure to analyse anthropogenic pressures of urban origin on surface water of protected coastal agro-environmental wetlands (L'Albufera de Valencia Natural Park, Spain).

PubMed

Pascual-Aguilar, Juan; Andreu, Vicente; Picó, Yolanda

2013-12-15

Detection and spatial distribution of 14 drugs of abuse and 17 pharmaceuticals in surface waters was investigated to determine transport hydrological connectivity between urban, agriculture and natural environments. Solid-phase extraction and liquid chromatography tandem mass spectrometry was applied to all samples. To determine spatial incidence of contaminants, analytical results of target compounds were georeferenced and integrated into a geographical information systems structure together with layers of municipal population, location of sewage water treatment plants and irrigation channels and sectors. The methodology was applied to L'Albufera Natural Park in Valencia (Spain). A total of 9 drugs of abuse were detected at 16 points (76% of the sample sites). Cocaine and its metabolite, benzoylecgonine, were the most detected substances, being found in 12 and 16 samples, respectively. Maximum concentrations were found in benzoylecgonine (78.71 ng/L) and codeine (51.60 ng/L). Thirteen pharmaceuticals were found at 16 points. The most detected compounds were carbamazepine (15 samples) and ibuprofen (11 samples). Maximum concentrations were detected in acetaminophen (17,699.4 ng/L), ibuprofen (3913.7 ng/L) and codeine (434.0 ng/L). Spatial distribution of pharmaceuticals showed a clear relationship between irrigation areas, high population densities municipalities (above 1000 h/km(2)) and sewage water treatment plants. Copyright © 2013 Elsevier B.V. All rights reserved.

Use of natural and applied tracers to guide targeted remediation efforts in an acid mine drainage system, Colorado Rockies, USA

USGS Publications Warehouse

Cowie, Rory; Williams, Mark W.; Wireman, Mike; Runkel, Robert L.

2014-01-01

Stream water quality in areas of the western United States continues to be degraded by acid mine drainage (AMD), a legacy of hard-rock mining. The Rico-Argentine Mine in southwestern Colorado consists of complex multiple-level mine workings connected to a drainage tunnel discharging AMD to passive treatment ponds that discharge to the Dolores River. The mine workings are excavated into the hillslope on either side of a tributary stream with workings passing directly under the stream channel. There is a need to define hydrologic connections between surface water, groundwater, and mine workings to understand the source of both water and contaminants in the drainage tunnel discharge. Source identification will allow targeted remediation strategies to be developed. To identify hydrologic connections we employed a combination of natural and applied tracers including isotopes, ionic tracers, and fluorescent dyes. Stable water isotopes (δ18O/δD) show a well-mixed hydrological system, while tritium levels in mine waters indicate a fast flow-through system with mean residence times of years not decades or longer. Addition of multiple independent tracers indicated that water is traveling through mine workings with minimal obstructions. The results from a simultaneous salt and dye tracer application demonstrated that both tracer types can be successfully used in acidic mine water conditions.

Measurement of tritium in natural water

NASA Astrophysics Data System (ADS)

Li, Meifen

1985-06-01

A detergent-scintillation liquid mixture applied to measure low specific activity of tritium in natural water was studied. The DYS-1 low level liquid scintillation counter designed and manufactured by our institute was employed. In comparing the Triton X-100 scintillation liquid mixture with the dioxane-based-scintillation liquid, a better formula for Triton X-100 scintillation liquid mixture was determined, the mixture possesses the quality of high water content; high efficiency and low back-ground in measuring tritium in water. Chemiluminescence of the Triton X-100 scintillation liquid mixture can be totally de-excited in short time. It can be employed at ambient temperature 11 28°C. For 20ml sample in quartz vials, counting efficiency is 15% with a background 2.17 cpm, Y=31 TU (t=30 min).

Modeling adsorption of cationic surfactants at air/water interface without using the Gibbs equation.

PubMed

Phan, Chi M; Le, Thu N; Nguyen, Cuong V; Yusa, Shin-ichi

2013-04-16

The Gibbs adsorption equation has been indispensable in predicting the surfactant adsorption at the interfaces, with many applications in industrial and natural processes. This study uses a new theoretical framework to model surfactant adsorption at the air/water interface without the Gibbs equation. The model was applied to two surfactants, C14TAB and C16TAB, to determine the maximum surface excesses. The obtained values demonstrated a fundamental change, which was verified by simulations, in the molecular arrangement at the interface. The new insights, in combination with recent discoveries in the field, expose the limitations of applying the Gibbs adsorption equation to cationic surfactants at the air/water interface.

Protecting Water Quality With Smart Growth Strategies and Natural Stormwater Management in Sussex County, Delaware

EPA Pesticide Factsheets

The report describes a technical assistance project that explored how smart growth and sustainable stormwater management approaches (known as green infrastructure) could be applied to Sussex County, DE.

Resource analysis and land use planning with space and high altitude photography

NASA Technical Reports Server (NTRS)

Schrumpf, B. J.

1972-01-01

Photographic scales providing resource data for decision making processes of land use and a legend system for barren lands, water resources, natural vegetation, agricultural, urban, and industrial lands in hierarchical framework are applied to various remote sensing techniques. Two natural vegetation resource and land use maps for a major portion of Maricopa County, Arizona are also produced.

Characterization of biofilm formation in natural water subjected to low-frequency electromagnetic fields.

PubMed

Mercier, Anne; Bertaux, Joanne; Lesobre, Jérôme; Gravouil, Kevin; Verdon, Julien; Imbert, Christine; Valette, Eric; Héchard, Yann

2016-01-01

Electromagnetic field (EMF) treatment has proven to be effective against mineral scaling in water systems. Therefore, it should be assessed for the treatment of other deposits such as biofilms. In this study, a commercial device producing low-frequency EMF (1-10 kHz) was applied to a reactor fed with natural water for 45 days. The treatment promoted the concentration of microorganisms in suspension and limited the amount of sessile microorganisms in the biofilm, as determined by the measurement of total DNA, qPCR and microscopy. The structure of the bacterial community was assessed by t-RFLP and pyrosequencing analysis. The results showed that EMF treatment affected both planktonic and sessile community composition. EMFs were responsible for a shift in classes of Proteobacteria during development of the biofilm. It may be speculated that the EMF treatment affected particle solubility and/or microorganism hydration. This study indicated that EMFs modulated biofilm formation in natural water.

Chemical Tracer Methods: Chapter 7

USGS Publications Warehouse

Healy, Richard W.

2017-01-01

Tracers have a wide variety of uses in hydrologic studies: providing quantitative or qualitative estimates of recharge, identifying sources of recharge, providing information on velocities and travel times of water movement, assessing the importance of preferential flow paths, providing information on hydrodynamic dispersion, and providing data for calibration of water flow and solute-transport models (Walker, 1998; Cook and Herczeg, 2000; Scanlon et al., 2002b). Tracers generally are ions, isotopes, or gases that move with water and that can be detected in the atmosphere, in surface waters, and in the subsurface. Heat also is transported by water; therefore, temperatures can be used to trace water movement. This chapter focuses on the use of chemical and isotopic tracers in the subsurface to estimate recharge. Tracer use in surface-water studies to determine groundwater discharge to streams is addressed in Chapter 4; the use of temperature as a tracer is described in Chapter 8.Following the nomenclature of Scanlon et al. (2002b), tracers are grouped into three categories: natural environmental tracers, historical tracers, and applied tracers. Natural environmental tracers are those that are transported to or created within the atmosphere under natural processes; these tracers are carried to the Earth’s surface as wet or dry atmospheric deposition. The most commonly used natural environmental tracer is chloride (Cl) (Allison and Hughes, 1978). Ocean water, through the process of evaporation, is the primary source of atmospheric Cl. Other tracers in this category include chlorine-36 (36Cl) and tritium (3H); these two isotopes are produced naturally in the Earth’s atmosphere; however, there are additional anthropogenic sources of them.

COMMENTS ON THE DEFINITION OF THE CURIE, WITH SPECIAL REFERENCE TO NATURAL RADIOACTIVE MATERIALS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaeger, R.G.; Houtermans, H.

1962-06-01

An analysis of maximum permissible levels of radionuclides showed that the definition of the curie, when applied to natural radioactive materials, is ambiguous. The history of the definition of the curie is reviewed. In the past, no clear distinction was raade between the curie as a unit of the quantity of a radioactive substance, and the curie as a unit of radioactivity. This has caused different interpretation of the curic as applied to natural radioactive materials, e.g., natural uranium and natural thorium. A redefinition of the curie as a pure unit of radioactivity is suggested, and maximum permissible levels ormore » concentrations of natural radioactive materials, such as uranium or thorium, should be stated in mass per unit mass or volume of air, water, food, etc. It is recommended that, in legislation listing the amounts of naturally occurring radioactive substances, these amounts be stated in milligrams or Kilograms. (auth)« less

Rapid, sensitive and direct analysis of exopolysaccharides from biofilm on aluminum surfaces exposed to sea water using MALDI-TOF MS.

PubMed

Hasan, Nazim; Gopal, Judy; Wu, Hui-Fen

2011-11-01

Biofilm studies have extensive significance since their results can provide insights into the behavior of bacteria on material surfaces when exposed to natural water. This is the first attempt of using matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) for detecting the polysaccharides formed in a complex biofilm consisting of a mixed consortium of marine microbes. MALDI-MS has been applied to directly analyze exopolysaccharides (EPS) in the biofilm formed on aluminum surfaces exposed to seawater. The optimal conditions for MALDI-MS applied to EPS analysis of biofilm have been described. In addition, microbiologically influenced corrosion of aluminum exposed to sea water by a marine fungus was also observed and the fungus identity established using MALDI-MS analysis of EPS. Rapid, sensitive and direct MALDI-MS analysis on biofilm would dramatically speed up and provide new insights into biofilm studies due to its excellent advantages such as simplicity, high sensitivity, high selectivity and high speed. This study introduces a novel, fast, sensitive and selective platform for biofilm study from natural water without the need of tedious culturing steps or complicated sample pretreatment procedures. Copyright © 2011 John Wiley & Sons, Ltd.

Establishing and testing a catchment water footprint framework to inform sustainable irrigation water use for an aquifer under stress.

PubMed

le Roux, Betsie; van der Laan, Michael; Vahrmeijer, Teunis; Bristow, Keith L; Annandale, John G

2017-12-01

Future water scarcities in the face of an increasing population, climate change and the unsustainable use of aquifers will present major challenges to global food production. The ability of water footprints (WFs) to inform water resource management at catchment-scale was investigated on the Steenkoppies Aquifer, South Africa. Yields based on cropping areas were multiplied with season-specific WFs for each crop to determine blue and green water consumption by agriculture. Precipitation and evapotranspiration of natural vegetation and other uses of blue water were included with the agricultural WFs to compare water availability and consumption in a catchment sustainability assessment. This information was used to derive a water balance and develop a catchment WF framework that gave important insights into the hydrology of the aquifer through a simplified method. This method, which requires the monitoring of only a few key variables, including rainfall, agricultural production, WFs of natural vegetation and other blue water flows, can be applied to inform the sustainability of catchment scale water use (as opposed to more complex hydrological studies). Results indicate that current irrigation on the Steenkoppies Aquifer is unsustainable. This is confirmed by declining groundwater levels, and suggests that there should be no further expansion of irrigated agriculture on the Steenkoppies Aquifer. Discrepancies between in- and outflows of water in the catchment indicated that further development of the WF approach is required to improve understanding of the geohydrology of the aquifer and to set and meet sustainability targets for the aquifer. It is envisaged that this 'working' framework can be applied to other water-stressed aquifers around the world. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Treatment of industrial effluent water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levitskii, Yu.N.

1982-09-01

This article reports on a thematic exhibition on ''New Developments in Treatment of Natural and Effluent Water'' in the Sanitary-Technical Construction Section at the Exhibition of Achievements of the National Economy of the USSR. The exhibition acquainted visitors with the achievements of leading organizations in different branches of industry with respect to treatment of natural and industrial effluent water. The Kharkov ''Vodkanalproekt'' Institute and the Kharkov affiliate of the All-Union Scientific-Research Institute of Water and Geodesy has jointly developed a ''Polymer-25'' filter for removal of oil products from nonexplosive effluent water discharged by machine building plants. A Baku affiliate hasmore » developed a new ShFP-1 screw-type press filter for dewatering the sediments from water treatment plants as well as for sediments from chemical, food, and other types of plants. The State Institute for Applied Chemistry has designed a continuous process plant for treating effluent water and removing toxic organic waste by converting them into mineral salts with high efficiency.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The site observational work plan (SOWP) for the Riverton, Wyoming, Uranium Mill Tailings Remedial Action (UMTRA) Project Site is the first document for the UMTRA Ground Water Project to address site-specific activities to meet compliance with the U.S. Environmental Protection Agency (EPA) proposed ground water standards (52 FR 36000 (1987)). In support of the activities the regulatory framework and drivers are presented along with a discussion of the relationship of this SOWP to other UMTRA Ground Water Project programmatic documents. A combination of the two compliance strategies that will be recommended for this site are no remediation with the applicationmore » of alternate concentration levels (ACL) and natural flushing in conjunction with institutional controls. ACLs are to be applied to constituents that occur at concentrations above background levels but which are essential nutrients and occur within nutritional ranges and/or have very low toxicity and high dietary intake rates compared to the levels detected in the ground water. The essential premise of natural flushing is that ground water movement and natural attenuation processes will reduce the detected contamination to background levels within 1 00 years. These two recommended compliance strategies were evaluated by applying Riverton site-specific data to the compliance framework developed in the UMTRA Ground Water programmatic environmental impact statement. There are three aquifers beneath the site: a surficial unconfined aquifer, a middle semiconfined aquifer, and a deeper confined aquifer. The milling-related contamination at the site has affected both the surficial and semiconfined aquifers, although the leaky shale aquifers separating these units limits the downward migration of contamination into the semiconfined aquifer. A shale aquitard separates the semiconfined aquifer from the underlying confined aquifer which has not been contaminated by milling-related constituents.« less

Possible effects of groundwater pumping on surface water in the Verde Valley, Arizona

USGS Publications Warehouse

Leake, Stanley A.; Haney, Jeanmarie

2010-01-01

The U.S. Geological Survey (USGS), in cooperation with The Nature Conservancy, has applied a groundwater model to simulate effects of groundwater pumping and artificial recharge on surface water in the Verde Valley sub-basin of Arizona. Results are in two sets of maps that show effects of locations of pumping or recharge on streamflow. These maps will help managers make decisions that will meet water needs and minimize environmental impacts.

An agent-based hydroeconomic model to evaluate water policies in Jordan

NASA Astrophysics Data System (ADS)

Yoon, J.; Gorelick, S.

2014-12-01

Modern water systems can be characterized by a complex network of institutional and private actors that represent competing sectors and interests. Identifying solutions to enhance water security in such systems calls for analysis that can adequately account for this level of complexity and interaction. Our work focuses on the development of a hierarchical, multi-agent, hydroeconomic model that attempts to realistically represent complex interactions between hydrologic and multi-faceted human systems. The model is applied to Jordan, one of the most water-poor countries in the world. In recent years, the water crisis in Jordan has escalated due to an ongoing drought and influx of refugees from regional conflicts. We adopt a modular approach in which biophysical modules simulate natural and engineering phenomena, and human modules represent behavior at multiple scales of decision making. The human modules employ agent-based modeling, in which agents act as autonomous decision makers at the transboundary, state, organizational, and user levels. A systematic nomenclature and conceptual framework is used to characterize model agents and modules. Concepts from the Unified Modeling Language (UML) are adopted to promote clear conceptualization of model classes and process sequencing, establishing a foundation for full deployment of the integrated model in a scalable object-oriented programming environment. Although the framework is applied to the Jordanian water context, it is generalizable to other regional human-natural freshwater supply systems.

Differentiating the Spatiotemporal Distribution of Natural and Anthropogenic Processes on River Water-Quality Variation Using a Self-Organizing Map With Factor Analysis.

PubMed

Wang, Yeuh-Bin; Liu, Chen-Wuing; Lee, Jin-Jing

2015-08-01

To elucidate the historical improvement and advanced measure of river water quality in the Taipei metropolitan area, this study applied the self-organizing map (SOM) technique with factor analysis (FA) to differentiate the spatiotemporal distribution of natural and anthropogenic processes on river water-quality variation spanning two decades. The SOM clustered river water quality into five groups: very low pollution, low pollution, moderate pollution, high pollution, and very high pollution. FA was then used to extract four latent factors that dominated water quality from 1991 to 2011 including three anthropogenic process factors (organic, industrial, and copper pollution) and one natural process factor [suspended solids (SS) pollution]. The SOM revealed that the water quality improved substantially over time. However, the downstream river water quality was still classified as high pollution because of an increase in anthropogenic activity. FA showed the spatiotemporal pattern of each factor score decreasing over time, but the organic pollution factor downstream of the Tamsui River, as well as the SS factor scores in the upstream major tributary (the Dahan Stream), remained within the high pollution level. Therefore, we suggest that public sewage-treatment plants should be upgraded from their current secondary biological processing to advanced treatment processing. The conservation of water and soil must also be reinforced to decrease the SS loading of the Dahan Stream from natural erosion processes in the future.

Parametric distribution approach for flow availability in small hydro potential analysis

NASA Astrophysics Data System (ADS)

Abdullah, Samizee; Basri, Mohd Juhari Mat; Jamaluddin, Zahrul Zamri; Azrulhisham, Engku Ahmad; Othman, Jamel

2016-10-01

Small hydro system is one of the important sources of renewable energy and it has been recognized worldwide as clean energy sources. Small hydropower generation system uses the potential energy in flowing water to produce electricity is often questionable due to inconsistent and intermittent of power generated. Potential analysis of small hydro system which is mainly dependent on the availability of water requires the knowledge of water flow or stream flow distribution. This paper presented the possibility of applying Pearson system for stream flow availability distribution approximation in the small hydro system. By considering the stochastic nature of stream flow, the Pearson parametric distribution approximation was computed based on the significant characteristic of Pearson system applying direct correlation between the first four statistical moments of the distribution. The advantage of applying various statistical moments in small hydro potential analysis will have the ability to analyze the variation shapes of stream flow distribution.

Measuring free metal ion concentrations in situ in natural waters using the Donnan Membrane Technique.

PubMed

Kalis, Erwin J J; Weng, Liping; Dousma, Freerk; Temminghoff, Erwin J M; Van Riemsdijk, Willem H

2006-02-01

Metal toxicity is not related to the total but rather to the free or labile metal ion concentration. One of the techniques that can be used to measure several free metal ion concentrations simultaneously is the Donnan Membrane Technique (DMT) in combination with the inductively coupled plasma-mass spectrometer (ICP-MS). However, free metal ion concentrations in natural waters are commonly below the detection limit of ICP-MS. We decreased the detection limit by making use of a ligand, and we developed a field DMT cell that can be applied in situ in natural waters. A kinetic approach can be used to calculate free metal ion concentrations when the equilibrium time becomes too large. The field DMT measured in situ in natural waters a free metal ion concentration ranging from 0.015% (Cu) to 13% (Zn) of a total metal concentration ranging from 0.06 nM (Cd) to 237 nM (Zn). The free metal ion concentrations were difficult to predict using an equilibrium speciation model, probably due to the uncertainty in the nature of the dissolved organic matter or the presence of other reactive colloids. It is shown that DMT can follow changes in the free metal ion concentration on times scales less than a day under certain conditions.

Evaluation of strategies for nature-based solutions to drought: a decision support model at the national scale

NASA Astrophysics Data System (ADS)

Simpson, Mike; Ives, Matthew; Hall, Jim

2016-04-01

There is an increasing body of evidence in support of the use of nature based solutions as a strategy to mitigate drought. Restored or constructed wetlands, grasslands and in some cases forests have been used with success in numerous case studies. Such solutions remain underused in the UK, where they are not considered as part of long-term plans for supply by water companies. An important step is the translation of knowledge on the benefits of nature based solutions at the upland/catchment scale into a model of the impact of these solutions on national water resource planning in terms of financial costs, carbon benefits and robustness to drought. Our project, 'A National Scale Model of Green Infrastructure for Water Resources', addresses this issue through development of a model that can show the costs and benefits associated with a broad roll-out of nature based solutions for water supply. We have developed generalised models of both the hydrological effects of various classes and implementations of nature-based approaches and their economic impacts in terms of construction costs, running costs, time to maturity, land use and carbon benefits. Our next step will be to compare this work with our recent evaluation of conventional water infrastructure, allowing a case to be made in financial terms and in terms of security of water supply. By demonstrating the benefits of nature based solutions under multiple possible climate and population scenarios we aim to demonstrate the potential value of using nature based solutions as a component of future long-term water resource plans. Strategies for decision making regarding the selection of nature based and conventional approaches, developed through discussion with government and industry, will be applied to the final model. Our focus is on keeping our work relevant to the requirements of decision-makers involved in conventional water planning. We propose to present the outcomes of our model for the evaluation of nature-based solutions at catchment scale and ongoing results of our national-scale model.

Natural biopolymer-based nanocomposite films for packaging applications.

PubMed

Rhim, Jong-Whan; Ng, Perry K W

2007-01-01

Concerns on environmental waste problems caused by non-biodegradable petrochemical-based plastic packaging materials as well as the consumer's demand for high quality food products has caused an increasing interest in developing biodegradable packaging materials using annually renewable natural biopolymers such as polysaccharides and proteins. Inherent shortcomings of natural polymer-based packaging materials such as low mechanical properties and low water resistance can be recovered by applying a nanocomposite technology. Polymer nanocomposites, especially natural biopolymer-layered silicate nanocomposites, exhibit markedly improved packaging properties due to their nanometer size dispersion. These improvements include increased modulus and strength, decreased gas permeability, and increased water resistance. Additionally, biologically active ingredients can be added to impart the desired functional properties to the resulting packaging materials. Consequently, natural biopolymer-based nanocomposite packaging materials with bio-functional properties have a huge potential for application in the active food packaging industry. In this review, recent advances in the preparation of natural biopolymer-based films and their nanocomposites, and their potential use in packaging applications are addressed.

40 CFR 230.53 - Aesthetics.

Code of Federal Regulations, 2010 CFR

2010-07-01

... aquatic ecosystems apply to the quality of life enjoyed by the general public and property owners. (b... ecosystems by degrading water quality, creating distracting disposal sites, inducing inappropriate... quality, disrupt natural substrate and vegetational characteristics, deny access to or visibility of the...

40 CFR 230.53 - Aesthetics.

Code of Federal Regulations, 2011 CFR

2011-07-01

... aquatic ecosystems apply to the quality of life enjoyed by the general public and property owners. (b... ecosystems by degrading water quality, creating distracting disposal sites, inducing inappropriate... quality, disrupt natural substrate and vegetational characteristics, deny access to or visibility of the...

40 CFR 230.53 - Aesthetics.

Code of Federal Regulations, 2013 CFR

2013-07-01

... aquatic ecosystems apply to the quality of life enjoyed by the general public and property owners. (b... ecosystems by degrading water quality, creating distracting disposal sites, inducing inappropriate... quality, disrupt natural substrate and vegetational characteristics, deny access to or visibility of the...

40 CFR 230.53 - Aesthetics.

Code of Federal Regulations, 2012 CFR

2012-07-01

... aquatic ecosystems apply to the quality of life enjoyed by the general public and property owners. (b... ecosystems by degrading water quality, creating distracting disposal sites, inducing inappropriate... quality, disrupt natural substrate and vegetational characteristics, deny access to or visibility of the...

40 CFR 230.53 - Aesthetics.

Code of Federal Regulations, 2014 CFR

2014-07-01

... aquatic ecosystems apply to the quality of life enjoyed by the general public and property owners. (b... ecosystems by degrading water quality, creating distracting disposal sites, inducing inappropriate... quality, disrupt natural substrate and vegetational characteristics, deny access to or visibility of the...

The Use of Stable Isotope Tracers to Quantify the Transit Time Distribution of Water

NASA Astrophysics Data System (ADS)

Gray, T. M.; Troch, P. A. A.

2016-12-01

Water pollution is an important societal problem because it can have harmful effects on human and ecological health. In order to improve water quality, scientists must develop land management methods that can avoid or mitigate environmental pollution. State of the art tools to develop such methods are flow and transport models that trace water and other solutes through the landscape. These models deliver important information that can lead to remediation efforts, and improve the quality of water for humans, plants, and animals. However, these models may be difficult to apply since many details about the catchment may not be available. Instead, a lumped approach is often used to find the water transit time using stable isotope tracers such as 18O and 2H that are naturally applied by precipitation to a catchment. The transit time distribution of water is an important indicator for the amount of solutes soil water and groundwater can contain, and thus a predictor of water quality. We conducted a 2-week long experiment using a tilted weighing lysimeter at Biosphere 2 to observe the breakthrough curves of deuterium and specific artificial DNA particles. We show that hydrological parameters can be computed in order to provide an estimate for the transit time distribution of deuterium. The convolution integral is then used to determine the distribution of the water transit time in the system. Unfortunately, stable isotopes such as deuterium make it difficult to pinpoint a specific flowpath since they naturally occur in the environment. Recent studies have shown that DNA tracers are able to trace water through the landscape. We found that DNA has a similar breakthrough curve happening at similar timescales as the deuterium. Therefore, DNA tracers may be able to identify sources of nonpoint source pollution in the future.

Pawcatuck River and Narragansett Bay Drainage Basins Water and Related Land Resources Study. Big River Reservoir Project. Volume I. Main Report.

DTIC Science & Technology

1981-07-01

Bristol County Water Company Kent County Water Authority Audubon Society of Rhode Island Rhode Island League of Women Voters Ecology Action for Rhode Island...restoration, or improvement of the quality of certain natural and cultural resources and ecological systems. The NED objectives can be achieved by...achieved by the same project purposes, if properly applied. Flood control measures that include or allow preser- vation of ecologically valuable wetland

The efficiency of macroporous polystyrene ion-exchange resins in natural organic matter removal from surface water

NASA Astrophysics Data System (ADS)

Urbanowska, Agnieszka; Kabsch-Korbutowicz, Małgorzata

2017-11-01

Natural water sources used for water treatment contains various organic and inorganic compounds. Surface waters are commonly contaminated with natural organic matter (NOM). NOM removal from water is important e.g. due to lowering the risk of disinfection by-product formation during chlorination. Ion exchange with the use of synthetic ion-exchange resins is an alternative process to typical NOM removal approach (e.g. coagulation, adsorption or oxidation) as most NOM compounds have anionic character. Moreover, neutral fraction could be removed from water due to its adsorption on resin surface. In this study, applicability of two macroporous, polystyrene ion exchange resins (BD400FD and A100) in NOM removal from water was assessed including comparison of treatment efficiency in various process set-ups and conditions. Moreover, resin regeneration effectivity was determined. Obtained results shown that examined resins could be applied in NOM removal and it should be noticed that column set-up yielded better results (contrary to batch set-up). Among the examined resins A100 one possessed better properties. It was determined that increase of solution pH resulted in a slight decrease in treatment efficiency while higher temperature improved it. It was also observed that regeneration efficiency was comparable in both tested methods but batch set-up required less reagents.

Stormwater harvesting for irrigation purposes: an investigation of chemical quality of water recycled in pervious pavement system.

PubMed

Nnadi, Ernest O; Newman, Alan P; Coupe, Stephen J; Mbanaso, Fredrick U

2015-01-01

Most available water resources in the world are used for agricultural irrigation. Whilst this level of water use is expected to increase due to rising world population and land use, available water resources are expected to become limited due to climate change and uneven rainfall distribution. Recycled stormwater has the potential to be used as an alternative source of irrigation water and part of sustainable water management strategy. This paper reports on a study to investigate whether a sustainable urban drainage system (SUDS) technique, known as the pervious pavements system (PPS) has the capability to recycle water that meets irrigation water quality standard. Furthermore, the experiment provided information on the impact of hydrocarbon (which was applied to simulate oil dripping from parked vehicles onto PPS), leaching of nutrients from different layers of the PPS and effects of nutrients (applied to enhance bioremediation) on the stormwater recycling efficiency of the PPS. A weekly dose of 6.23 × 10(-3) L of lubricating oil and single dose of 17.06 g of polymer coated controlled-release fertilizer granules were applied to the series of 710 mm × 360 mm model pervious pavement structure except the controls. Rainfall intensity of 7.4 mm/h was applied to the test models at the rate of 3 events per week. Analysis of the recycled water showed that PPS has the capability to recycle stormwater to a quality that meets the chemical standards for use in agricultural irrigation irrespective of the type of sub-base used. There is a potential benefit of nutrient availability in recycled water for plants, but care should be taken not to dispose of this water in natural water courses as it might result in eutrophication problems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Precisely Determining Ultralow level UO22+ in Natural Water with Plasmonic Nanowire Interstice Sensor

NASA Astrophysics Data System (ADS)

Gwak, Raekeun; Kim, Hongki; Yoo, Seung Min; Lee, Sang Yup; Lee, Gyoung-Ja; Lee, Min-Ku; Rhee, Chang-Kyu; Kang, Taejoon; Kim, Bongsoo

2016-01-01

Uranium is an essential raw material in nuclear energy generation; however, its use raises concerns about the possibility of severe damage to human health and the natural environment. In this work, we report an ultrasensitive uranyl ion (UO22+) detection method in natural water that uses a plasmonic nanowire interstice (PNI) sensor combined with a DNAzyme-cleaved reaction. UO22+ induces the cleavage of DNAzymes into enzyme strands and released strands, which include Raman-active molecules. A PNI sensor can capture the released strands, providing strong surface-enhanced Raman scattering signal. The combination of a PNI sensor and a DNAzyme-cleaved reaction significantly improves the UO22+ detection performance, resulting in a detection limit of 1 pM and high selectivity. More importantly, the PNI sensor operates perfectly, even in UO22+-contaminated natural water samples. This suggests the potential usefulness of a PNI sensor in practical UO22+-sensing applications. We anticipate that diverse toxic metal ions can be detected by applying various ion-specific DNA-based ligands to PNI sensors.

Xanthoceraside hollow gold nanoparticles, green pharmaceutics preparation for poorly water-soluble natural anti-AD medicine.

PubMed

Meng, Da-Li; Shang, Lei; Feng, Xiao-He; Huang, Xing-Fei; Che, Xin

2016-06-15

In order to increase the solubility of poorly water-soluble natural product, xanthoceraside, an effective anti-AD compound from Xanthoceras sorbifolia Bunge, and maintain its natural property, the xanthoceraside hollow gold nanoparticles were successively prepared by green ultrasonic method with silica spheres as templates and HF solution as selective etching solvent. Hollow gold nanoparticles and drug-loaded hollow gold nanoparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The solubilities of xanthoceraside loaded on hollow gold nanoparticles were increased obviously from 3.0μg/ml and 2.5μg/ml to 12.7μg/ml and 10.7μg/ml at 25°C and 37°C, respectively. The results of XRD and DSC indicated that the reason for this increase was mainly due to the amorphous state of xanthoceraside loaded on the hollow gold nanoparticles. In summary, the method of loading xanthoceraside onto hollow gold nanoparticles was a green and useful strategy to improve the solubility and dissolution of poorly water-soluble natural products and worth to applying to other natural products. Copyright © 2016 Elsevier B.V. All rights reserved.

Biogeochemical assessment of natural attenuation of JP-4-contaminated ground water in the presence of fluorinated surfactants.

PubMed

Levine, A D; Libelo, E L; Bugna, G; Shelley, T; Mayfield, H; Stauffer, T B

1997-12-22

The biogeochemistry of the natural attenuation of petroleum-contaminated ground water was investigated in a field study. The focus of the study was a fire training site located on Tyndall Air Force Base in Florida. The site has been used by the Air Force for approximately 11 years in fire fighting exercises. An on-site above-ground tank of JP-4 provided fuel for setting controlled fires for the exercises. Various amounts of water and aqueous film forming foams (AFFF) were applied to extinguish the fires. The sources of contamination included leaks from pipelines transporting the fuel, leaks from an oil/water separator and runoff and percolation from the fire fighting activities. Previous investigations had identified jet fuel contamination at the site, however, no active remediation efforts have been conducted to date. The goal of this study was to use biogeochemical monitoring data to delineate redox zones within the site and to identify evidence of natural attenuation of JP-4 contamination. In addition to identifying several hydrocarbon metabolites, fluorinated surfactants (AFFF) were detected down-gradient of the hydrocarbon plume.

Pulsed Reductive Doping in Titanium Dioxide: An Easy Way for Multiplying the Efficiency of Solar H2 Production from Water

NASA Astrophysics Data System (ADS)

Seferlis, Andreas K.; Neophytides, Stylianos G.

2014-08-01

Solar photoelectrochemical water splitting on TiO2 for H2 production has been investigated for many years and is still considered very promising. Despite the many advantages, Titania's UV-only absorption, limits its terrestrial practical applications. In space though, with the lack of ozone's natural UV filter, this handicap is lifted, rendering TiO2 an attractive candidate as photoelectrocatalyst in space applications. Reductive doping of TiO2 has been investigated over the years for its impressive results but, till now, without practical application due to the impermanent nature of the doping. In this work we present a method that not only multiplies TiO2 water splitting efficiency, but also is facile, stable and easily applied in working conditions.

The aqueous photolysis of α-pinene in solution with humic acid

USGS Publications Warehouse

Goldberg, Marvin C.; Cunningham, Kirkwood M.; Aiken, George R.; Weiner, Eugene R.; ,

1992-01-01

Terpenes are produced abundantly by environmental processes but are found in very low concentrations in natural waters. Aqueous photolysis of solutions containing α-pinene, a representative terpene, in the presence of humic acid resulted in degradation of the pinene. Comparison of this reaction to photolysis of α-pinene in the presence of methylene blue leads to the conclusion that the reactive pathway for the abiotic degradation of α-pinene is due to reaction with singlet oxygen produced by irradiation of the humic material. The initial product of single oxygen and α-pinene is a hydroperoxide. Since humic materials are prevalent in most natural waters, this mechanism of photodecomposition for α-pinene probably also applies to other terpenes in surface waters and may be reasonably considered to contribute to their low environmental concentration.

Water Resources: the Central Component of the WEF Nexus?

NASA Astrophysics Data System (ADS)

Ding, K.; Gunda, T.; Hornberger, G. M.

2017-12-01

Increasing population growth, consumption of natural resources, and deterioration of the environment coupled with climate change impacts (such as increased variability in precipitation) will challenge our abilities to provide water, energy and food (WEF) to the global populace. Less developed areas, such as the countries in Sub-Saharan Africa, are particularly vulnerable to such resource issues due to immature governance and management structures and strategies. We introduce an integrated approach to resource security analysis, which traditionally has focused on the WEF components separately and apply the methods to a suite of countries in Sub-Saharan Africa. Specifically, we evaluate the inter-connected nature of WEF securities by considering physical, demographic, socioeconomic, health, and institutional parameters related to each of the resource securities and by analyzing the relationships among the metrics. For example, reported food deficits for countries are strongly correlated with reported levels of access to safe drinking water. Multivariate statistical analyses are applied to identify relationships among resources and to develop indices that robustly and comprehensively capture the WEF nexus. Our results indicate that water plays the central role in the WEF nexus, due to its extensive use for both food and energy production in these countries. This approach provides a framework for analyzing the WEF nexus in other regions of the world.

Restrained Proton Indicator in Combined Quantum-Mechanics/Molecular-Mechanics Dynamics Simulations of Proton Transfer through a Carbon Nanotube.

PubMed

Duster, Adam W; Lin, Hai

2017-09-14

Recently, a collective variable "proton indicator" was purposed for tracking an excess proton solvated in bulk water in molecular dynamics simulations. In this work, we demonstrate the feasibility of utilizing the position of this proton indicator as a reaction coordinate to model an excess proton migrating through a hydrophobic carbon nanotube in combined quantum-mechanics/molecular-mechanics simulations. Our results indicate that applying a harmonic restraint to the proton indicator in the bulk solvent near the nanotube pore entrance leads to the recruitment of water molecules into the pore. This is consistent with an earlier study that employed a multistate empirical valence bond potential and a different representation (center of excess charge) of the proton. We attribute this water recruitment to the delocalized nature of the solvated proton, which prefers to be in high-dielectric bulk solvent. While water recruitment into the pore is considered an artifact in the present simulations (because of the artificially imposed restraint on the proton), if the proton were naturally restrained, it could assist in building water wires prior to proton transfer through the pore. The potential of mean force for a proton translocation through the water-filled pore was computed by umbrella sampling, where the bias potentials were applied to the proton indicator. The free energy curve and barrier heights agree reasonably with those in the literature. The results suggest that the proton indicator can be used as a reaction coordinate in simulations of proton transport in confined environments.

Developing Sustainable Urban Water-Energy Infrastructures: Applying a Multi-Sectoral Social-Ecological-Infrastructural Systems (SEIS) Framework

NASA Astrophysics Data System (ADS)

Ramaswami, A.

2016-12-01

Urban infrastructure - broadly defined to include the systems that provide water, energy, food, shelter, transportation-communication, sanitation and green/public spaces in cities - have tremendous impact on the environment and on human well-being (Ramaswami et al., 2016; Ramaswami et al., 2012). Aggregated globally, these sectors contribute 90% of global greenhouse gas (GHG) emissions and 96% of global water withdrawals. Urban infrastructure contributions to such impacts are beginning to dominate. Cities are therefore becoming the action arena for infrastructure transformations that can achieve high levels of service delivery while reducing environmental impacts and enhancing human well-being. Achieving sustainable urban infrastructure transitions requires: information about the engineered infrastructure, and its interaction with the natural (ecological-environmental) and the social sub-systems In this paper, we apply a multi-sector, multi-scalar Social-Ecological-Infrastructural Systems framework that describes the interactions among biophysical engineered infrastructures, the natural environment and the social system in a systems-approach to inform urban infrastructure transformations. We apply the SEIS framework to inform water and energy sector transformations in cities to achieve environmental and human health benefits realized at multiple scales - local, regional and global. Local scales address pollution, health, wellbeing and inequity within the city; regional scales address regional pollution, scarcity, as well as supply risks in the water-energy sectors; global impacts include greenhouse gas emissions and climate impacts. Different actors shape infrastructure transitions including households, businesses, and policy actors. We describe the development of novel cross-sectoral strategies at the water-energy nexus in cities, focusing on water, waste and energy sectors, in a case study of Delhi, India. Ramaswami, A.; Russell, A.G.; Culligan, P.J.; Sharma, K.R.; Kumar, E. (2016). Meta-Principles for developing smart, sustainable, and healthy cities, Science, 352(6288), 940-3. Ramaswami, A., et al. A Social-Ecological Infrastructural Systems Framework for Inter-Disciplinary Study of Sustainable City-Systems. J. Ind Ecol, 16(6): 801-813, 2012.

Twinning European and South Asian river basins to enhance capacity and implement adaptive integrated water resources management approaches - results from the EC-project BRAHMATWINN

NASA Astrophysics Data System (ADS)

Flügel, W.-A.

2011-04-01

The EC-project BRAHMATWINN was carrying out a harmonised integrated water resources management (IWRM) approach as addressed by the European Water Initiative (EWI) in headwater river systems of alpine mountain massifs of the twinning Upper Danube River Basin (UDRB) and the Upper Brahmaputra River Basins (UBRB) in Europe and Southeast Asia respectively. Social and natural scientists in cooperation with water law experts and local stakeholders produced the project outcomes presented in Chapter 2 till Chapter 10 of this publication. BRAHMATWINN applied a holistic approach towards IWRM comprising climate modelling, socio-economic and governance analysis and concepts together with methods and integrated tools of applied Geoinformatics. A detailed description of the deliverables produced by the BRAHMATWINN project is published on the project homepage http://www.brahmatwinn.uni-jena.de.

Development of new critical fluid-based processing methods for nutraceuticals and natural products

DOE Office of Scientific and Technical Information (OSTI.GOV)

King, J. W.

2004-01-01

The development of new supercritical fluid processing technology as applied to nutraceuticals and natural products is no longer confined to using just supercritical fluid extraction (SFE) and supercritical carbon dioxide (SC-CO{sub 2}). Recently reported advances have been focused on modifying natural products and improving functionality of an end product using newer experimental techniques and fluid phases. In this presentation four focus areas will be emphasized: (1) control of particle size/morphology and encapsulation of the nutraceutical ingredients, (2) the use of combinatorial methodology to optimize critical fluid processing, (3) application of sub-critical water as a complementary medium for processing natural products,more » and (4) an assessment of the current state of products and processing which use critical fluid to produce nutraceutical and natural products for the food and cosmetic marketplace. Application of the various particle fomiation processes conducted in the presence of critical fluid media, such as: CPF, SAS, DELOS, RESS, PGSS, and GAS, can be used to produce particles of small and uniform distribution, having unique morphologies, that facilitate rapid dissolution or sustained release of many nutraceutical ingredients. These substances have included: therapeutic spices, phystosterols, vitamins, phospholpids, and carotenoids. Accelerating the development of critical fluid processing has been the application of combinatorial methodology to optimize extraction, fractionation, and/or reactions in near-, SC-, or subcritical fluid media. This is frequently accomplished by using sequential or multichannel automated instrumentation that was originally designed for analytical purposes. Several examples will be provided of rapidly assessing the extraction of anthocyanins with sub-critical water and the SFE of natural products. However, differences do exist in conducting experiments on the above instrumentation vs. scaled-up continuous processes, which will be noted. Sub-critical water is finding increase use as an extraction/fractionation or reaction medium. The literature reports applications for the extraction spices, natural antioxidants (rosemary, anthocyanins, etc.), and herbal components (tea and coffee ingredients), Our studies and the literature provide adequate correlations of solute solubility in sub-critical water as well as models for the kinetics of extraction in this medium. Finally, the current state of critical fluid technology as applied to natural products and nutraceuticals will be assessed; noting specific processes, organizations, and products that exist.« less

Comparison of two filtration-elution procedures to improve the standard methods ISO 10705-1 & 2 for bacteriophage detection in groundwater, surface water and finished water samples.

PubMed

Helmi, K; Jacob, P; Charni-Ben-Tabassi, N; Delabre, K; Arnal, C

2011-09-01

To select a reliable method for bacteriophage concentration prior detection by culture from surface water, groundwater and drinking water to enhance the sensitivity of the standard methods ISO 10705-1 & 2. Artificially contaminated (groundwater and drinking water) and naturally contaminated (surface water) 1-litre samples were processed for bacteriophages detection. The spiked samples were inoculated with about 150 PFU of F-specific RNA bacteriophages and somatic coliphages using wastewater. Bacteriophage detection in the water samples was achieved using the standard method without and with a concentration step (electropositive Anodisc membrane or a pretreated electronegative Micro Filtration membrane, MF). For artificially contaminated matrices (drinking and ground waters), recovery rates using the concentration step were superior to 70% whilst analyses without concentration step mainly led to false negative results. Besides, the MF membrane presented higher performances compared with the Anodisc membrane. The concentration of a large volume of water (up to one litre) on a filter membrane avoids false negative results obtained by direct analysis as it allows detecting low number of bacteriophages in water samples. The addition of concentration step before applying the standard method could be useful to enhance the reliability of bacteriophages monitoring in water samples as bio-indicators to highlight faecal pollution. © No claim to French Government works. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

Developing Intelligent System Dynamic Management Instruments on Water-Food-Energy Nexus in Response to Urbanization

NASA Astrophysics Data System (ADS)

Tsai, W. P.; Chang, F. J.; Lur, H. S.; Fan, C. H.; Hu, M. C.; Huang, T. L.

2016-12-01

Water, food and energy are the most essential natural resources needed to sustain life. Water-Food-Energy Nexus (WFE Nexus) has nowadays caught global attention upon natural resources scarcity and their interdependency. In the past decades, Taiwan's integrative development has undergone drastic changes due to population growth, urbanization and excessive utilization of natural resources. The research intends to carry out interdisciplinary studies on WFE Nexus based on data collection and analysis as well as technology innovation, with a mission to develop a comprehensive solution to configure the synergistic utilization of WFE resources in an equal and secure manner for building intelligent dynamic green cities. This study aims to establish the WFE Nexus through interdisciplinary research. This study will probe the appropriate and secure resources distribution and coopetition relationship by applying and developing techniques of artificial intelligence, system dynamics, life cycle assessment, and synergy management under data mining, system analysis and scenario analysis. The issues of synergy effects, economic benefits and sustainable social development will be evaluated as well. First, we will apply the system dynamics to identify the interdependency indicators of WFE Nexus in response to urbanization and build the dynamic relationship among food production, irrigation water resource and energy consumption. Then, we conduct comparative studies of WFE Nexus between the urbanization and the un-urbanization area (basin) to provide a referential guide for optimal resource-policy nexus management. We expect to the proposed solutions can help achieve the main goals of the research, which is the promotion of human well-being and moving toward sustainable green economy and prosperous society.

How reliable are environmental data on 'orphan' elements? The case of bismuth concentrations in surface waters.

PubMed

Filella, Montserrat

2010-01-01

Like all elements of the periodic table, bismuth is ubiquitously distributed throughout the environment as a result of natural processes and human activities. It is present as Bi(III) in environmental, biological and geochemical samples. Although bismuth and its compounds are considered to be non-toxic to humans, its increasing use as a replacement for lead has highlighted how little is known about its environmental and ecotoxicological behaviour. In this first critical review paper on the existing information on bismuth occurrence in natural waters, 125 papers on fresh and marine waters have been collated. Although the initial objective of this study was to establish the range of the typical concentrations of total dissolved bismuth in natural waters, this proved impossible to achieve due to the wide, and hitherto unexplained, dispersion of published data. Since analytical limitations might be one of the reasons underlying value dispersion, new analytical methods published since 2000--intended to be applied to natural waters--have also been reviewed. Disappointingly, the detection limits of the bulk of them are well above those required; they are thus of limited usefulness. Analysis of the existing information on bismuth in secondary references (i.e., books, review chapters) and on its chemical speciation in seawater revealed that the uncritical reproduction of old data is a widespread practice.

Water and vegetation indices by using MODIS products for eucalyptus, pasture, and natural ecosystems in the eastern São Paulo state, Southeast Brazil

NASA Astrophysics Data System (ADS)

de C. Teixeira, Antônio H.; Leivas, Janice F.; Ronquim, Carlos C.; Garçon, Edlene A. M.; Bayma-Silva, Gustavo

2017-10-01

Eucalyptus (Ec) and pasture (Pt) are expanding while natural vegetation (Nv) are losing space in the Paraíba Valley, eastern side of the São Paulo state, Southeast Brazil. For quantification of water and vegetation conditions, the MODIS product MOD13Q1 was used together with a net of weather stations and vegetation land masks during the year 2015. The SAFER algorithm was applied to retrieve the actual evapotranspiration (ET), which was combined with the Monteith's radiation use efficiency (RUE) model to estimate the biomass production (BIO). Three moisture indices were applied, the climatic water balance ratio (WBr), the ratio of precipitation (P) to ET, the water balance deficit (WBd), the difference between P and ET, and the evapotranspiration ratio (ETr), the ratio of ET to the reference evapotranspiration (ET0). On the one hand, the highest ET rates for the Ec ecosystem should be a negative aspect under water scarcity conditions; however, it presented the best water productivity. Although the Ec ecosystem presenting the lowest WBr and WBd values, it had the highest ETr, averaging 0.92, when comparing to those for Nv (0.88) and Pt (0.79). These results indicated that eucalyptus plants have greater ability of conserving soil moisture in their root zones, increasing WP, when comparing with Pt and Nv ecosystems. These water relationships are relevant issues under the land-use change conditions in the Paraiba Valley, confirming the suitability of using the MODIS products together with weather stations to study the ecosystem dynamics.

Degradation of ketoprofen by sulfate radical-based advanced oxidation processes: Kinetics, mechanisms, and effects of natural water matrices.

PubMed

Feng, Yiping; Song, Qingyun; Lv, Wenying; Liu, Guoguang

2017-12-01

Ketoprofen (KET) is a mostly used nonsteroidal anti-inflammatory drug that has been frequently detected in wastewater effluents and surface waters. In this study, we investigated the degradation of KET by sulfate radical (SO 4 - ) based advanced oxidation processes (SR-AOPs) in aqueous solution. The degradation kinetics, mechanisms, and effects of natural water matrices on thermally activated persulfate (TAP) oxidation of KET were systematically investigated. Increasing the temperature and persulfate (PS) concentrations greatly enhanced the degradation of KET. KET degradation is pH-dependent with an optimum pH of 5.0. Reactions in the presence of radical quenchers revealed the dominant role of SO 4 - in oxidizing KET. Water matrix significantly influenced the degradation of KET. The common inorganic anions present in natural waters exhibited inhibitory effect on KET degradation, and the inhibition followed the order of Cl -  > CO 3 2-  > HCO 3 -  > NO 3 - ; however, no significant inhibition of KET degradation was observed in the presence of Ca 2+ and Mg 2+ cations. The presence of natural organic matter (NOM) suppressed KET degradation, and the suppression increased as NOM concentration increase. Products identification and mineralization experiments revealed that KET and its degradation intermediates were finally transformed into CO 2 and H 2 O. The results of this study indicated that applying SR-AOPs for the remediation of KET contaminated water matrix is technically possible. Copyright © 2017 Elsevier Ltd. All rights reserved.

Solar or UVA-Visible Photocatalytic Ozonation of Water Contaminants.

PubMed

Beltrán, Fernando J; Rey, Ana

2017-07-14

An incipient advanced oxidation process, solar photocatalytic ozonation (SPO), is reviewed in this paper with the aim of clarifying the importance of this process as a more sustainable water technology to remove priority or emerging contaminants from water. The synergism between ozonation and photocatalytic oxidation is well known to increase the oxidation rate of water contaminants, but this has mainly been studied in photocatalytic ozonation systems with lamps of different radiation wavelength, especially of ultraviolet nature (UVC, UVB, UVA). Nowadays, process sustainability is critical in environmental technologies including water treatment and reuse; the application of SPO systems falls into this category, and contributes to saving energy and water. In this review, we summarized works published on photocatalytic ozonation where the radiation source is the Sun or simulated solar light, specifically, lamps emitting radiation to cover the UVA and visible light spectra. The main aspects of the review include photoreactors used and radiation sources applied, synthesis and characterization of catalysts applied, influence of main process variables (ozone, catalyst, and pollutant concentrations, light intensity), type of water, biodegradability and ecotoxicity, mechanism and kinetics, and finally catalyst activity and stability.

Hydrodynamic cavitation in combination with the ozone, hydrogen peroxide and the UV-based advanced oxidation processes for the removal of natural organic matter from drinking water.

PubMed

Čehovin, Matej; Medic, Alojz; Scheideler, Jens; Mielcke, Jörg; Ried, Achim; Kompare, Boris; Žgajnar Gotvajn, Andreja

2017-07-01

Natural organic matter in drinking water is causing concern especially due to the formation of disinfection by-products (DBPs) by chlorine, as these are proven to have adverse health effects on consumers. In this research, humic acid was used as a source of dissolved organic carbon (DOC) in drinking water (up to 3mgL -1 ). The efficiency of DOC removal was studied by applying O 3 , H 2 O 2 /O 3 , H 2 O 2 /UV and O 3 /UV advanced oxidation processes (AOPs) alone and combined with hybrid hydrodynamic cavitation (HC), generated by an orifice plate, as this technology recently shows promising potential for the treatment of water, containing recalcitrant organic substances. It was observed that the combined treatment by HC could significantly affect the performance of the applied AOPs, with as little as 3-9 passes through the cavitation generators. For O 3 and H 2 O 2 dosages up to 2 and 4mgL -1 , respectively, and UV dosage up to 300mJcm -2 , HC enhanced DOC removal by 5-15% in all combinations, except for O 3 /UV AOPs. Overall, the potential benefits of HC for DOC removal were emphasized for low ratio between applied oxidants to DOC and high UV absorbance of the sample. Investigated DBPs formation potentials require special attention for H 2 O 2 /UV AOPs and combinations with HC. Copyright © 2017 Elsevier B.V. All rights reserved.

Variation of desiccation tolerance and longevity in fern spores

USDA-ARS?s Scientific Manuscript database

This work contributes to the understanding of plant cell responses to water stress when applied at different intensity and duration. Fern spores are used to explore survival at relative humidity (RH) < 85% because their unicellular nature eliminates complexities that may arise in multicellular orga...

EFFECT OF SEPARATION PROCESSES ON THE FORMATION OF BROMINATED THMS

EPA Science Inventory

Separation treatment processes are being investigated as a way to control the formation of disinfection by-products (DBPs) in finished waters. These processes remove natural organic matter before a disinfection is applied, thus limiting the amount of material available to form D...

Coupling socioeconomic and lake systems for sustainability: a conceptual analysis using Lake St. Clair region as a case study.

PubMed

Mavrommati, Georgia; Baustian, Melissa M; Dreelin, Erin A

2014-04-01

Applying sustainability at an operational level requires understanding the linkages between socioeconomic and natural systems. We identified linkages in a case study of the Lake St. Clair (LSC) region, part of the Laurentian Great Lakes system. Our research phases included: (1) investigating and revising existing coupled human and natural systems frameworks to develop a framework for this case study; (2) testing and refining the framework by hosting a 1-day stakeholder workshop and (3) creating a causal loop diagram (CLD) to illustrate the relationships among the systems' key components. With stakeholder assistance, we identified four interrelated pathways that include water use and discharge, land use, tourism and shipping that impact the ecological condition of LSC. The interrelationships between the pathways of water use and tourism are further illustrated by a CLD with several feedback loops. We suggest that this holistic approach can be applied to other case studies and inspire the development of dynamic models capable of informing decision making for sustainability.

Fluorometric Index for Sensing Oil in the Sea Environment.

PubMed

Baszanowska, Emilia; Otremba, Zbigniew

2017-06-02

Excitation-emission matrix spectroscopy (EEMS) was applied to determine the fluorometric index (FI) as a parameter indicating the presence of a source of oil pollution in a specific area of the sea. Seawater from the Polish coast (the Baltic Sea) and the same water combined with various amounts of crude oil extracted from the Baltic Sea shelf ( Petrobaltic -type oil) were used in this study. The FI values were calculated for excitation and emission wavelengths found at the maximal peak, taking into account the natural seawater and the seawater artificially contaminated (for an oil-to-water ratio range of 0.5 × 10 -6 - 500 × 10 -6 ). The wavelength configurations (Ex/Em) (225/355 and 225/340) for the FI index were applied. It was found that, independent of the amount of oil, the FI achieves a higher value for natural seawater than for seawater that has had contact with oil. These results provide the basis to design a sensor signaling the appearance of oil in a defined sea area.

Everglades Depth Estimation Network (EDEN) Applications: Tools to View, Extract, Plot, and Manipulate EDEN Data

USGS Publications Warehouse

Telis, Pamela A.; Henkel, Heather

2009-01-01

The Everglades Depth Estimation Network (EDEN) is an integrated system of real-time water-level monitoring, ground-elevation data, and water-surface elevation modeling to provide scientists and water managers with current on-line water-depth information for the entire freshwater part of the greater Everglades. To assist users in applying the EDEN data to their particular needs, a series of five EDEN tools, or applications (EDENapps), were developed. Using EDEN's tools, scientists can view the EDEN datasets of daily water-level and ground elevations, compute and view daily water depth and hydroperiod surfaces, extract data for user-specified locations, plot transects of water level, and animate water-level transects over time. Also, users can retrieve data from the EDEN datasets for analysis and display in other analysis software programs. As scientists and managers attempt to restore the natural volume, timing, and distribution of sheetflow in the wetlands, such information is invaluable. Information analyzed and presented with these tools is used to advise policy makers, planners, and decision makers of the potential effects of water management and restoration scenarios on the natural resources of the Everglades.

Herbicide monitoring in soil, runoff waters and sediments in an olive orchard.

PubMed

Calderon, Maria Jesus; De Luna, Elena; Gomez, Jose Alfonso; Hermosin, M Carmen

2016-11-01

Occurrences of surface water contamination by herbicides in areas where olive orchards are established reveal a need to understand soil processes affecting herbicide fate at field scale for this popular Mediterranean crop. A monitoring study with two herbicides (terbuthylazine and oxyfluorfen) in the first 2cm of soil, runoff waters, and sediments, was carried out after under natural rainfall conditions following winter herbicide application. At the end of the 107day field experiment, no residues of the soil applied terbuthylazine were recovered, whereas 42% of the oxyfluorfen applied remained in the top soil. Very low levels of both herbicides were measured in runoff waters; however, concentrations were slightly higher for terbuthylazine (0.53% of applied) than for oxyfluorfen (0.03% of applied), relating to their respective water solubilities. Congruent with soil residue data, 38.15% of the applied oxyfluorfen was found in runoff-sediment, compared to only 0.46% for terbuthylazine. Accordingly, the herbicide soil distribution coefficients measured within runoff field tanks was much greater for oxyfluorfen (Kd=3098) than for terbuthylazine (Kd=1.57). The herbicide oxyfluorfen is co-transported with sediment in runoff, remaining trapped and/or adsorbed to soil particle aggregates, due in part to its low water solubility. In contrast, terbuthylazine soil dissipation may be associated more so with leaching processes, favored by its high water solubility, low sorption, and slow degradation. By comparing these two herbicides, our results reaffirm the importance of herbicide physico-chemical properties in dictating their behavior in soil and also suggest that herbicides with low solubility, as seen in the case oxyfluorfen, remain susceptible to offsite transport associated with sediments. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of municipal biosolids to dry-land wheat fields - A monitoring program near Deer Trail, Colorado (USA). A presentation for an international conference: "The Future of Agriculture: Science, Stewardship, and Sustainability", August 7-9, 2006, Sacramento, CA

USGS Publications Warehouse

Crock, James G.; Smith, David B.; Yager, Tracy J.B.

2006-01-01

Since late 1993, Metro Wastewater Reclamation District of Denver (Metro District), a large wastewater treatment plant in Denver, Colorado, has applied Grade I, Class B biosolids to about 52,000 acres of non-irrigated farmland and rangeland near Deer Trail, Colorado. In cooperation with the Metro District in 1993, the U.S. Geological Survey (USGS) began monitoring ground water at part of this site. In 1999, the USGS began a more comprehensive study of the entire site to address stakeholder concerns about the chemical effects of biosolids applications. This more comprehensive monitoring program has recently been extended through 2010. Monitoring components of the more comprehensive study included biosolids collected at the wastewater treatment plant, soil, crops, dust, alluvial and bedrock ground water, and stream bed sediment. Streams at the site are dry most of the year, so samples of stream bed sediment deposited after rain were used to indicate surface-water effects. This presentation will only address biosolids, soil, and crops. More information about these and the other monitoring components are presented in the literature (e.g., Yager and others, 2004a, b, c, d) and at the USGS Web site for the Deer Trail area studies at http://co.water.usgs.gov/projects/CO406/CO406.html. Priority parameters identified by the stakeholders for all monitoring components, included the total concentrations of nine trace elements (arsenic, cadmium, copper, lead, mercury, molybdenum, nickel, selenium, and zinc), plutonium isotopes, and gross alpha and beta activity, regulated by Colorado for biosolids to be used as an agricultural soil amendment. Nitrogen and chromium also were priority parameters for ground water and sediment components. In general, the objective of each component of the study was to determine whether concentrations of priority parameters (1) were higher than regulatory limits, (2) were increasing with time, or (3) were significantly higher in biosolids-applied areas than in a similar farmed area where biosolids were not applied. Where sufficient samples could be collected, statistical methods were used to evaluate effects. Rigorous quality assurance was included in all aspects of the study. The roles of hydrology and geology also were considered in the design, data collection, and interpretation phases of the study. Study results indicate that the chemistry of the biosolids from the Denver plant was consistent during 1999-2005, and total concentrations of regulated trace elements were consistently lower than the regulatory limits. Plutonium isotopes were not detected in the biosolids. Leach tests using deionized water to simulate natural precipitation indicate arsenic, molybdenum, and nickel were the most soluble priority parameters in the biosolids. Study results show no significant difference in concentrations of priority parameters between biosolids-applied soils and unamended soils where no biosolids were applied. However, biosolids were applied only twice during 1999-2003. The next soil sampling is not scheduled until 2010. To date concentrations of most of the priority parameters were not much greater in the biosolids than in natural soil from the sites. Therefore, many more biosolids applications would need to occur before biosolids effects on the soil priority constituents can be quantified. Leach tests using deionized water to simulate precipitation indicate that molybdenum and selenium were the priority parameters that were most soluble in both biosolids-applied soil and natural or unamended soil. Study results do not indicate significant differences in concentrations of priority parameters between crops grown in biosolids-applied areas and crops grown where no biosolids were applied. However, crops were grown only twice during 1999-2003, so only two crop samples could be collected. The wheat-grain elemental data collected during 1999-2003 for both biosolids-applied areas and unamended areas are similar

Band gaps and localization of surface water waves over large-scale sand waves with random fluctuations

NASA Astrophysics Data System (ADS)

Zhang, Yu; Li, Yan; Shao, Hao; Zhong, Yaozhao; Zhang, Sai; Zhao, Zongxi

2012-06-01

Band structure and wave localization are investigated for sea surface water waves over large-scale sand wave topography. Sand wave height, sand wave width, water depth, and water width between adjacent sand waves have significant impact on band gaps. Random fluctuations of sand wave height, sand wave width, and water depth induce water wave localization. However, random water width produces a perfect transmission tunnel of water waves at a certain frequency so that localization does not occur no matter how large a disorder level is applied. Together with theoretical results, the field experimental observations in the Taiwan Bank suggest band gap and wave localization as the physical mechanism of sea surface water wave propagating over natural large-scale sand waves.

China's transboundary waters: new paradigms for water and ecological security through applied ecology.

PubMed

He, Daming; Wu, Ruidong; Feng, Yan; Li, Yungang; Ding, Chengzhi; Wang, Wenling; Yu, Douglas W

2014-10-01

China is Asia's most important upstream riparian country, sharing 110 rivers and lakes with 18 downstream countries. Consequently, China's management of transboundary water resources must consider both environmental and geopolitical risks.The major threats to and conflicts over international rivers in China revolve around biotic homogenisation due to the installation of transport links, water allocation, water pollution, alteration of natural flow patterns and disruption of fisheries due to the installation of hydropower dams, and droughts and floods exacerbated by climate change. Because these problems have an international component, they fall under China's Peaceful Rise strategy, mandating that transboundary conflicts be resolved amicably as part of the overarching goal of increasing regional economic growth with as little conflict as possible.Science-backed policy is more likely to result in long term, mutually agreeable solutions; the results of applied ecological research have already resulted in a number of mitigation measures, including setting operational thresholds to reduce the downstream impact of dams, designating protected areas along key river stretches where dams cannot be installed (one dam in a critical location has been cancelled), and the installation of terrestrial protected-area networks. Synthesis and applications . Applied ecology will continue to play an important role in the diagnosis and resolution of environmental threats to China's transboundary waters. More importantly, applied ecology can inform the development of a transboundary environmental compensation mechanism and regional consultative mechanisms that support informed, cooperative decision-making for China and its riparian neighbours.

China's transboundary waters: new paradigms for water and ecological security through applied ecology

PubMed Central

He, Daming; Wu, Ruidong; Feng, Yan; Li, Yungang; Ding, Chengzhi; Wang, Wenling; Yu, Douglas W

2014-01-01

China is Asia's most important upstream riparian country, sharing 110 rivers and lakes with 18 downstream countries. Consequently, China's management of transboundary water resources must consider both environmental and geopolitical risks. The major threats to and conflicts over international rivers in China revolve around biotic homogenisation due to the installation of transport links, water allocation, water pollution, alteration of natural flow patterns and disruption of fisheries due to the installation of hydropower dams, and droughts and floods exacerbated by climate change. Because these problems have an international component, they fall under China's Peaceful Rise strategy, mandating that transboundary conflicts be resolved amicably as part of the overarching goal of increasing regional economic growth with as little conflict as possible. Science-backed policy is more likely to result in long term, mutually agreeable solutions; the results of applied ecological research have already resulted in a number of mitigation measures, including setting operational thresholds to reduce the downstream impact of dams, designating protected areas along key river stretches where dams cannot be installed (one dam in a critical location has been cancelled), and the installation of terrestrial protected-area networks. Synthesis and applications. Applied ecology will continue to play an important role in the diagnosis and resolution of environmental threats to China's transboundary waters. More importantly, applied ecology can inform the development of a transboundary environmental compensation mechanism and regional consultative mechanisms that support informed, cooperative decision-making for China and its riparian neighbours. PMID:25558084

APPLYING THE CLEAN WATER ACT SO THAT WE FIX THE RIGHT THINGS

EPA Science Inventory

Determining the cause of a biological impairment can be a daunting task, one that is complicated by multiple possible causes, spotty or irregularly collected data, natural variations due to season, weather, land formation and other factors, and a lack of basic scientific informat...

Water reclamation during drinking water treatments using polyamide nanofiltration membranes on a pilot scale.

PubMed

Kukučka, Miroslav; Kukučka, Nikoleta; Habuda-Stanić, Mirna

2016-09-01

The aim of this study was to investigate the performances of polyamide nanofiltration membranes during water reclamation. The study was conducted using nanofiltration concentrates obtained from two different nanofiltration drinking water treatment plants placed in the northern part of Serbia (Kikinda and Zrenjanin). Used nanofiltration concentrates contained high concentrations of arsenic (45 and 451 μg/L) and natural organic matter (43.1 and 224.40 mgKMnO4/L). Performances of polyamide nanofiltration membranes during water reclamation were investigated under various fluxes and transmembrane pressures in order to obtain drinking water from nanofiltration concentrates and, therefore, reduce the amount of produced concentrates and minimize the waste that has to be discharged in the environment. Applied polyamide nanofiltration membranes showed better removal efficiency during water reclamation when the concentrate with higher content of arsenic and natural organic matter was used while the obtained permeates were in accordance with European regulations. This study showed that total concentrate yield can be reduced to ~5 % of the optimum flux value, in both experiments. The obtained result for concentrate yield under the optimum flux presents considerable amount of reclaimed drinking water and valuable reduced quantity of produced wastewater.

Temporal Evolution of Water Use for Thermoelectric Generation

NASA Astrophysics Data System (ADS)

Reedy, R. C.; Scanlon, B. R.

2013-12-01

The long lifespan of power plants (30 - 50 yr) results in the current power plant fleet representing a legacy of past variations in fuel availability and costs, water availability and water rights, and advances in technologies, such as combined cycle plants, which impact trends in water consumption. The objective of this study was to reconstruct past water consumption and withdrawal of thermoelectric generation based on data on controls, including fuel types, generator technologies, and cooling systems, using Texas as a case study and comparing with the US. Fuel sources in Texas varied over time, from predominantly natural gas in the 1960s and early 1970s to coal and nuclear sources following the 1973 oil embargo and more recently to large increases in natural gas generation (85% increase 1998 - 2004) in response to hydraulic fracturing and low natural gas prices. The dominant generator technology in Texas was steam turbines until the early 1990s; however, combined cycle plants markedly increased in the late 1990s (400% increase 1998 - 2004). Proliferation of cooling ponds in Texas, mostly in the 1970s and 1980s (340% increase) reflects availability of large quantities of unappropriated surface water and increases in water rights permitting during this time and lower cost and higher cooling efficiency of ponds relative to wet cooling towers. Water consumption for thermoelectricity in Texas in 2010 totaled ~0.53 km3 (0.43 million acre feet, maf), accounting for ~4% of total state water consumption. High water withdrawals (32.3 km3, 26.2 maf) mostly reflect circulation between cooling ponds and power plants. About a third of the water withdrawals is not required for cooling and reflects circulation by idling plants being used as peaking plants. Controls on water consumption include (1) generator technology/thermal efficiency and (2) cooling system resulting in statewide consumption for natural gas combined cycle generators with mostly cooling towers being 60% lower than that of traditional coal, nuclear, or natural gas steam turbine generators with mostly cooling ponds. The primary control on water withdrawals is cooling system, with ~ two orders of magnitude lower withdrawals for cooling towers relative to once-through ponds statewide. Increases in natural gas combined cycle plants with cooling towers in response to high production of low-cost natural gas has greatly reduced water demand for thermoelectric cooling since 2000. A similar approach will be applied to thermoelectric generation throughout the US using information on fuel sources, generator technologies and cooling systems to better understand current water use for thermoelectric generation based on the legacy of past drivers and long lifespans of power plants. Understanding the historical evolution of water needs for thermoelectricity should allow us to better project future water needs.

Assessing Method to Identifying Water Resilience Against Natural and Climate Change Hazards.

NASA Astrophysics Data System (ADS)

Amril, Rofi; Maryono

2018-02-01

A geographic region may become vulnerable toward water resources in a variety of ways. Common issues arise when man-made infrastructure such as housing, industrial, agriculture and other spatial land use policy implementation exceeds more than desired level. Vulnerability of a region due to water resources could be interpreted as the inability of the region to sustaining economic and social activity associated to socio-economic water availability. This study assess four aspects of water resilience: water quantity, water distribution, water quality, and water requirements. Literature review then followed by interview with academic expert used as method of study. This study found that four aspect of water vulnerability mostly have been applied to asses water resource vulnerability. Each aspect have a specific characteristic and could be define more specific and detail indicator according to the local content.

Spatial clustering of metal and metalloid mixtures in unregulated water sources on the Navajo Nation - Arizona, New Mexico, and Utah, USA.

PubMed

Hoover, Joseph H; Coker, Eric; Barney, Yolanda; Shuey, Chris; Lewis, Johnnye

2018-08-15

Contaminant mixtures are identified regularly in public and private drinking water supplies throughout the United States; however, the complex and often correlated nature of mixtures makes identification of relevant combinations challenging. This study employed a Bayesian clustering method to identify subgroups of water sources with similar metal and metalloid profiles. Additionally, a spatial scan statistic assessed spatial clustering of these subgroups and a human health metric was applied to investigate potential for human toxicity. These methods were applied to a dataset comprised of metal and metalloid measurements from unregulated water sources located on the Navajo Nation, in the southwest United States. Results indicated distinct subgroups of water sources with similar contaminant profiles and that some of these subgroups were spatially clustered. Several profiles had metal and metalloid concentrations that may have potential for human toxicity including arsenic, uranium, lead, manganese, and selenium. This approach may be useful for identifying mixtures in water sources, spatially evaluating the clusters, and help inform toxicological research investigating mixtures. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

A hurricane modification process, applying a new technology tested for warm cloud seeding to produce artificial rains

NASA Astrophysics Data System (ADS)

Imai, T.; Martin, I.; Iha, K.

A Hurricane Modification Process with application of a new clean technology attested for seeding warm clouds with collector pure water droplets of controlled size to produce artificial rains in warm clouds is proposed to modify the hurricanes in order to avoid their formation or to modify the trajectory or to weaken hurricanes in action The Process is based on the time-dependent effects of cloud droplets microphysical processes for the formation and growth of the natural water droplets inside the clouds releasing large volumes of Aeolian energy to form the strong rotative upside air movements A new Paradigm proposed explain the strong and rotative winds created with the water droplets formation and grow process releasing the rotative Aeolian Energy in Tornados and Hurricanes This theory receive the Gold Medal Award of the Water Science in the 7th International Water Symposium 2005 in France Artificial seeding in the Process studies condensing a specified percentage of the water vapor to liquid water droplets where we observe the release of larges intensity of the Aeolian energy creates the hurricanes producing appreciable perturbations With they rotating strong wind created by the water droplets releasing Aeolian energy The Amplitudes of these winds are comparable to natural disasters Once this natural thermal process is completely understood artificial process to modify the hurricanes become scientifically possible to avoid them to happen or to deviate their trajectory or to weaken the already formed hurricanes In this work

Strategies to diagnose and control microbial souring in natural gas storage reservoirs and produced water systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morris, E.A.; Derr, R.M.; Pope, D.H.

1995-12-31

Hydrogen sulfide production (souring) in natural gas storage reservoirs and produced water systems is a safety and environmental problem that can lead to operational shutdown when local hydrogen sulfide standards are exceeded. Systems affected by microbial souring have historically been treated using biocides that target the general microbial community. However, requirements for more environmentally friendly solutions have led to treatment strategies in which sulfide production can be controlled with minimal impact to the system and environment. Some of these strategies are based on microbial and/or nutritional augmentation of the sour environment. Through research sponsored by the Gas Research Institute (GRI)more » in Chicago, Illinois, methods have been developed for early detection of microbial souring in natural gas storage reservoirs, and a variety of mitigation strategies have been evaluated. The effectiveness of traditional biocide treatment in gas storage reservoirs was shown to depend heavily on the methods by which the chemical is applied. An innovative strategy using nitrate was tested and proved ideal for produced water and wastewater systems. Another strategy using elemental iodine was effective for sulfide control in evaporation ponds and is currently being tested in microbially sour natural gas storage wells.« less

Application of water chemistry as a hydrological tracer in a volcano catchment area: A case study of the Tatun Volcano Group, North Taiwan

NASA Astrophysics Data System (ADS)

Lu, Hsueh-Yu

2014-04-01

In this paper, water chemistry is successfully applied to elucidate hydrological processes through the use of natural tracers in a hydrological system. The concept of a natural tracer is principally based on water-rock interaction. In this case, a volcanic watershed in the Tatun Volcano Group is examined with the hydrochemistry of the Peihuang Creek system analyzed in terms of acidic hydrothermal water. The application of principal component analysis demonstrates that the hydrochemistry of Peihuang Creek is dominated by mixing among three end members, Lujiaoken seep water, Matsao seep water and shallow circulated water. Conservative ions, such as halogens, reveal that recharge of shallow circulated water with low ionic concentration is dominant in the mountain area and gradually becomes insignificant in the plains area. Rare earth elements also confirm this derivation. In addition, rare earth elements demonstrate parallel pattern along the tributaries, which implies that the fractionation of rare earth elements is not considerable and dilution is the major factor attenuating the concentrations of rare earth elements. Therefore, the constant slope of REE pattern allows for semi-quantitative estimation of mixing proportion of the two major tributaries. The results show that Lujiaoken Creek supplies about 50% of waters to the downstream Peihuang Creek. Comparing commonly used nature tracers, such as Cl- and environmental isotopes, this study demonstrates that rare earth elements have the advantage of very low background concentrations and easily defined sources if fractionation is not considerable. Under this circumstance, the calculation of water mixing is applicable.

Ab initio simulation of particle momentum distributions in high-pressure water

NASA Astrophysics Data System (ADS)

Ceriotti, M.

2014-12-01

Applying pressure to water reduces the average oxygen-oxygen distance, and facilitates the delocalisation of protons along the hydrogen bond. This pressure-induced delocalisation is further enhanced by the quantum nature of hydrogen nuclei, which is very significant even well above room temperature. Here we will evaluate the quantum kinetic energy and the particle momentum distribution of hydrogen and oxygen nuclei in water at extreme pressure, using ab initio path integral molecular dynamics. We will show that (transient) dissociation of water molecules induce measurable changes in the kinetic energy hydrogen atoms, although current deep inelastic scattering experiments are probably unable to capture the heterogeneity of the sample.

MALDI-TOF MS for the Identification of Cultivable Organic-Degrading Bacteria in Contaminated Groundwater near Unconventional Natural Gas Extraction Sites.

PubMed

Santos, Inês C; Martin, Misty S; Carlton, Doug D; Amorim, Catarina L; Castro, Paula M L; Hildenbrand, Zacariah L; Schug, Kevin A

2017-08-10

Groundwater quality and quantity is of extreme importance as it is a source of drinking water in the United States. One major concern has emerged due to the possible contamination of groundwater from unconventional oil and natural gas extraction activities. Recent studies have been performed to understand if these activities are causing groundwater contamination, particularly with respect to exogenous hydrocarbons and volatile organic compounds. The impact of contaminants on microbial ecology is an area to be explored as alternatives for water treatment are necessary. In this work, we identified cultivable organic-degrading bacteria in groundwater in close proximity to unconventional natural gas extraction. Pseudomonas stutzeri and Acinetobacter haemolyticus were identified using matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF MS), which proved to be a simple, fast, and reliable method. Additionally, the potential use of the identified bacteria in water and/or wastewater bioremediation was studied by determining the ability of these microorganisms to degrade toluene and chloroform. In fact, these bacteria can be potentially applied for in situ bioremediation of contaminated water and wastewater treatment, as they were able to degrade both compounds.

MALDI-TOF MS for the Identification of Cultivable Organic-Degrading Bacteria in Contaminated Groundwater near Unconventional Natural Gas Extraction Sites

PubMed Central

Martin, Misty S.; Carlton, Doug D.; Castro, Paula M. L.; Hildenbrand, Zacariah L.; Schug, Kevin A.

2017-01-01

Groundwater quality and quantity is of extreme importance as it is a source of drinking water in the United States. One major concern has emerged due to the possible contamination of groundwater from unconventional oil and natural gas extraction activities. Recent studies have been performed to understand if these activities are causing groundwater contamination, particularly with respect to exogenous hydrocarbons and volatile organic compounds. The impact of contaminants on microbial ecology is an area to be explored as alternatives for water treatment are necessary. In this work, we identified cultivable organic-degrading bacteria in groundwater in close proximity to unconventional natural gas extraction. Pseudomonas stutzeri and Acinetobacter haemolyticus were identified using matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF MS), which proved to be a simple, fast, and reliable method. Additionally, the potential use of the identified bacteria in water and/or wastewater bioremediation was studied by determining the ability of these microorganisms to degrade toluene and chloroform. In fact, these bacteria can be potentially applied for in situ bioremediation of contaminated water and wastewater treatment, as they were able to degrade both compounds. PMID:28796186

Thoughts on applying existing toxicological understanding to risk assessment for major ions in fresh waters

EPA Science Inventory

Recent research in our laboratories and many others have greatly increased understanding of the responses of freshwater organisms to increased concentrations of major geochemical ions (Na, K, Ca, Mg, Cl, SO4, HCO3) in laboratory toxicity tests, stream mesocosms, and in natural st...

Emergency watershed treatments on burned lands in southwestern Oregon

Treesearch

Ed Gross; Ivars Steinblums; Curt Ralston; Howard Jubas

1989-01-01

Following extensive, natural wildfires on the Siskiyou National Forest in southwest Oregon during fall 1987, numerous rehabilitation measures were applied to severely burned public and private forest watersheds. Treatments were designed to prevent offsite degradation of water quality and fisheries, to minimize soil erosion and productivity losses, and to prevent...

WEPP model implementation project with the USDA-Natural Resources Conservation Service

USDA-ARS?s Scientific Manuscript database

The Water Erosion Prediction Project (WEPP) is a physical process-based soil erosion model that can be used to estimate runoff, soil loss, and sediment yield from hillslope profiles, fields, and small watersheds. Initially developed from 1985-1995, WEPP has been applied and validated across a wide r...

The transboundary nature of seabird ecology: Chapter 8

USGS Publications Warehouse

Jodice, Patrick G.R.; Suryan, Robert M.

2015-01-01

The term ‘seabird’ is generally applied to avian species that forage in the marine environment over open water. Seabirds typically nest in colonies and are long-lived species with low annual reproductive rates. Seabird breeding sites typically occur on islands or along coasts and as such are often at the boundaries of ecological or political zones. During the breeding season, seabirds cross a very distinct terrestrial/marine ecological boundary on a regular basis to forage. Even relatively ‘local’ species cross multiple jurisdictions within a day (e.g., state lands and waters, and federal waters) while pelagic species may transit through international waters on a daily, weekly, or monthly time-frame. Seabird life-histories expose individuals and populations to environmental conditions affecting both terrestrial and marine habitats. The wide-ranging and transboundary nature of seabird ecology also exposes these species to various environmental and anthropogenic forces such as contamination, commercial fisheries and climate forcing that also are transboundary in nature. Therefore, wherever conservation of seabirds or the management of their populations is the goal, consideration must be given to ecosystem dynamics on land and at sea. Because the jurisdiction of agencies does not cross the land-sea boundary in the same manner as the seabirds they are managing, these efforts are facilitated by multi-agency communication and collaboration. By their very nature and by the nature of the systems that they must function within, seabirds embody the complexity of wildlife ecology and conservation in the twenty-first century.

PbO2(s, plattnerite) reductive dissolution by natural organic matter: reductant and inhibitory subfractions.

PubMed

Shi, Zhi; Stone, Alan T

2009-05-15

Natural organic matter (NOM) is a diverse collection of molecules, each possessing its own reductant, complexant, and adsorption properties. Here, we are interested in the ability of NOM to bring about the reductive dissolution of Pb(IV)O2(s). Adding the coagulants FeCl3 or Al2(SO4)3 followed by membrane filtration is one way to remove a subset of NOM molecules from surface water samples. Another is to pass water samples through a granular activated carbon (GAC) column. Results from applying these treatments to Great Dismal Swamp water (DSW) and Nequasset Bog Water (NBW) can best be explained as follows: (i) GAC column treatment is more efficient at removing the NOM fraction most responsible for reductive dissolution. (ii) Coagulation/filtration, with either coagulant, is most efficient at removing a second, inhibitory fraction. Inhibition may arise from (i) adsorption at the mineral/water interface, which blocks approach of reductant molecules and (ii) a micelle-like aggregate nature, which provides hydrophobic pockets that capture reductantmolecules, again keeping them away from the mineral/water interface. Hypotheses regarding reductant and inhibitory fractions are further evaluated using representative low-molecular-weight compounds. Substituted hydroquinones are used as mimics of the reductant fraction, and malonic acid, quinic acid, trehalose, alginic acid, and polygalacturonic acid are used as mimics of the inhibitory fraction.

Hydrologic behavior of model slopes with synthetic water repellent soils

NASA Astrophysics Data System (ADS)

Zheng, Shuang; Lourenço, Sérgio D. N.; Cleall, Peter J.; Chui, Ting Fong May; Ng, Angel K. Y.; Millis, Stuart W.

2017-11-01

In the natural environment, soil water repellency decreases infiltration, increases runoff, and increases erosion in slopes. In the built environment, soil water repellency offers the opportunity to develop granular materials with controllable wettability for slope stabilization. In this paper, the influence of soil water repellency on the hydrological response of slopes is investigated. Twenty-four flume tests were carried out in model slopes under artificial rainfall; soils with various wettability levels were tested, including wettable (Contact Angle, CA < 90°), subcritical water repellent (CA ∼ 90°) and water repellent (CA > 90°). Various rainfall intensities (30 mm/h and 70 mm/h), slope angles (20° and 40°) and relative compactions (70% and 90%) were applied to model the response of natural and man-made slopes to rainfall. To quantitatively assess the hydrological response, a number of measurements were made: runoff rate, effective rainfall rate, time to ponding, time to steady state, runoff acceleration, total water storage and wetting front rate. Overall, an increase in soil water repellency reduces infiltration and shortens the time for runoff generation, with the effects amplified for high rainfall intensity. Comparatively, the slope angle and relative compaction had only a minor contribution to the slope hydrology. The subcritical water repellent soils sustained infiltration for longer than both the wettable and water repellent soils, which presents an added advantage if they are to be used in the built environment as barriers. This study revealed substantial impacts of man-made or synthetically induced soil water repellency on the hydrological behavior of model slopes in controlled conditions. The results shed light on our understanding of hydrological processes in environments where the occurrence of natural soil water repellency is likely, such as slopes subjected to wildfires and in agricultural and forested slopes.

The eutrophication history of a naturally eutrophic watercourse

NASA Astrophysics Data System (ADS)

Tammelin, Mira; Kauppila, Tommi

2015-04-01

For efficient inland water protection, it is essential to know the natural states of lakes or, at least, the reference conditions before intensive human impact. The estimation of the natural state is particularly difficult for geologically anomalous areas, where naturally eutrophic lakes are located within nutrient-poorer regions. This is because of the lack of monitoring data and pristine reference lakes and the poor functioning of regional paleoecological nutrient models in such anomalous areas. A paleoecological model that is specifically targeted to the anomalously eutrophic area, however, could be used to interpret the eutrophication histories and natural states of the naturally eutrophic lakes in that area. We applied a targeted paleoecological diatom-total phosphorus transfer function to examine the natural eutrophy and eutrophication history of a central basin and two upstream lakes of the anomalously nutrient-rich Iisalmi watercourse in Eastern Finland. In addition to the nutrient reconstruction based on stratigraphic diatom samples, we studied chrysophyte cyst to diatom ratio, taxonomic diversity and the magnetic susceptibility of the sediment core to find further evidence for possible changes in the lakes and their catchments. The results show that the three lakes are naturally eutrophic with average background total phosphorus levels between 40 μg/l - 60 μg/l. However, human-induced eutrophication has also affected the lakes, which can be seen as rapid changes in the diatom assemblages and magnetic susceptibility between the sediment depths of 40 cm and 90 cm. The modeled lake water total phosphorus concentration has increased less abruptly, approximately 20 μg/l altogether, and the reconstructions of the top sediments mainly correspond well with the water quality observations of the last few decades. The results of this study indicate that a targeted paleoecological nutrient model can be used to interpret the natural state and the eutrophication history of a locality that has anomalous water quality characteristics compared to its surroundings and where regional models perform poorly. Despite their exceptional natural conditions, these localities may often be very important economically, recreationally or historically, which is why we need to be able to focus water protection measures rationally and efficiently to them as well.

Removal of arsenate from groundwater by electrocoagulation method.

PubMed

Ali, Imran; Khan, Tabrez A; Asim, Mohd

2012-06-01

Arsenic, a toxic metalloid in drinking water, has become a major threat for human beings and other organisms. In the present work, attempts have been made to remove arsenate from the synthetic as well as natural water of Ballia district, India by electrocoagulation method. Efforts have also been made to optimize the various parameters such as initial arsenate concentration, pH, applied voltage, processing time, and working temperature. Electrocoagulation is a fast, inexpensive, selective, accurate, reproducible, and eco-friendly method for arsenate removal from groundwater. The present paper describes an electrocoagulation method for arsenate removal from groundwater using iron and zinc as anode and cathode, respectively. The maximum removal of arsenate was 98.8% at 2.0 mg L(-1), 7.0, 3.0 V, 10.0 min, and 30°C as arsenate concentration, pH, applied voltage, processing time, and working temperature, respectively. Relative standard deviation, coefficient of determination (r (2)), and confidence limits were varied from 1.50% to 1.59%, 0.9996% to 0.9998%, and 96.0% to 99.0%, respectively. The treated water was clear, colorless, and odorless without any secondary contamination. The developed and validated method was applied for arsenate removal of two samples of groundwater of Ballia district, U.P., India, having 0.563 to 0.805 mg L(-1), arsenate concentrations. The reported method is capable for the removal of arsenate completely (100% removal) from groundwater of Ballia district. There was no change in the groundwater quality after the removal of arsenate. The treated water was safe for drinking, bathing, and recreation purposes. Therefore, this method may be the choice of arsenate removal from natural groundwater.

Factors Affecting Comparative Resistance of Naturally Occurring and Subcultured Pseudomonas aeruginosa to Disinfectants

PubMed Central

Carson, L. A.; Favero, M. S.; Bond, W. W.; Petersen, N. J.

1972-01-01

A strain of Pseudomonas aeruginosa was isolated in pure culture from the reservoir of a hospital mist therapy unit by an extinction-dilution technique; its natural distilled water environment was used as a growth and maintenance medium. After a single subculture on Trypticase soy agar, the strain showed a marked decrease in resistance to inactivation by acetic acid, glutaraldehyde, chlorine dioxide, and a quaternary ammonium compound when compared with naturally occurring cells grown in mist therapy unit water. The following factors were observed to affect the relative resistances of naturally occurring and subcultured cells of the P. aeruginosa strain: (i) temperature at which the cultures were incubated prior to exposure to disinfectants, (ii) growth phase of the cultures at the time of exposure to disinfectants, (iii) nature of the suspending menstruum for disinfectants, and (iv) exposure to fluorescent light during incubation of inocula prior to testing. The applied significance of these findings may alter the present concepts of disinfectant testing as well as routine control procedures in the hospital environment. PMID:4624209

Cream concentrated latex for foam rubber products

NASA Astrophysics Data System (ADS)

Suksup, R.; Imkaew, C.; Smitthipong, W.

2017-12-01

Fresh natural latex (around 40% rubber and 60% water) can be transformed to concentrated natural latex (around 60% rubber and 40% water) in order to realise economical transportation and easier latex product’s preparation. The concentrated natural latex is an extremely valuable material. It can be applied for many types of products, for example, foam rubber as pillow and mattress, elastic band, etc. Industrially, the concentrated natural latex can be prepared by centrifugation which requires an enormous expensive machine. From the eco-friendly products point of view, most of rubber entrepreneurs in the world try to develop a green rubber product. So, the main objective of this study is to prepare the cream concentrated latex without any sophisticated machine. Thus, we work on a simple, cheap and green method that does not use any expensive machine but uses water-based chemical as sodium alginate to prepare the cream concentrated latex. The optimal amount of sodium alginate in the latex was studied. The main characteristics of the cream concentrated latex were tested by various technics, such as alkalinity, total solid content (TSC), dry rubber content (DRC), etc. We found that there are no significant differences of results between fresh natural latex and cream concentrated latex, except for the TSC and DRC. The TSC and DRC of cream latex are higher than those of fresh natural latex. Finally, we propose a model of natural rubber particle and sodium alginate to form the cream concentrated latex.

Innovative physico-chemical treatment of wastewater incorporating Moringa oleifera seed coagulant.

PubMed

Bhuptawat, Hitendra; Folkard, G K; Chaudhari, Sanjeev

2007-04-02

Moringa oleifera is a pan tropical, multipurpose tree whose seeds contain a high quality edible oil (up to 40% by weight) and water soluble proteins that act as effective coagulants for water and wastewater treatment. The use of this natural coagulant material has not yet realised its potential. A water extract of M. oleifera seed was applied to a wastewater treatment sequence comprising coagulation-flocculation-sedimentation-sand filtration. The study was laboratory based using an actual wastewater. Overall COD removals of 50% were achieved at both 50 and 100mg/l M. oleifera doses. When 50 and 100mg/l seed doses were applied in combination with 10mg/l of alum, COD removal increased to 58 and 64%, respectively. The majority of COD removal occurred during the filtration process. In the tests incorporating alum, sludge generation and filter head loss increased by factors of 3 and 2, respectively. These encouraging treatment results indicate that this may be the first treatment application that can move to large scale adoption. The simple water extract may be obtained at minimal cost from the presscake residue remaining after oil extraction from the seed. The regulatory compliance issues of adopting 'new materials' for wastewater treatment are significantly less stringent than those applying to the production of potable water.

Mathematical modeling of systemic factors determining the risk of deterioration of drinking water supply and development of allergic diseases of population

NASA Astrophysics Data System (ADS)

Bespalov, Yurii G.; Nosov, Konstantin V.; Vysotska, Olena V.; Porvan, Andrii P.; Omiotek, Zbigniew; Burlibay, Aron; Assembay, Azat; Szatkowska, Małgorzata

2017-08-01

This study aims at mathematical modeling of systemic factors threatening the sanitary and hygienic state of sources of water supply. It is well-known, that this state affects health of population consuming water from different water sources (lakes, reservoirs, rivers). In particular, water quality problem may cause allergic reactions that are the important problem of health care. In the paper, the authors present the mathematical model, that enables on the basis of observations of a natural system to predict the system's behavior and determine the risks related to deterioration of drinking water resources. As a case study, we uses supply of drinking water from Lake Sevan, but the approach developed in the study can be applied to wide area of adjacent problems.

Tilt and strain deformation induced by hydrologically active natural fractures: application to the tiltmeters installed in Sainte-Croix-aux-Mines observatory (France)

NASA Astrophysics Data System (ADS)

Longuevergne, Laurent; Florsch, Nicolas; Boudin, Frédéric; Oudin, Ludovic; Camerlynck, Christian

2009-08-01

We investigate the deformation induced by water pressure variations in hydrologically active natural fractures, and recorded by tiltmeters and strainmeters. The deformation associated with a single fracture is derived using finite-element modelling (FEM). A range in fracture geometries is explored, first to highlight the sensitivity of each geometrical parameter to the deformation, and secondly to allow transfer to observation sites. Water level variations in the fracture are then derived from a hydrological model, driven by observed rainfall, and calibrated on fracture water flow measurements. The modelling results are explicitly applied to constrain the local hydrological contribution to observations with the 100-m-long hydrostatic tiltmeter installed at Sainte-Croix-aux-Mines (France). Our study shows that well-founded physical modelling of local hydrological effect allows a substantial correction of records in observatories.

Solid-phase extraction of heavy metal ions on bucky tubes disc in natural water and herbal plant samples.

PubMed

Soylak, Mustafa; Unsal, Yunus Emre

2011-10-01

A preconcentration-separation procedure has been established based on solid-phase extraction of Fe(III) and Pb(II) on bucky tubes (BTs) disc. Fe(III) and Pb(II) ions were quantitatively recovered at pH 6. The influences of the analytical parameters like sample volume, flow rates on the recoveries of analytes on BT disc were investigated. The effects of co-existing ions on the recoveries were also studied. The detection limits for iron and lead were found 1.6 and 4.9 μg L⁻¹, respectively. The validation of the presented method was checked by the analysis of TMDA-51.3 fortified water certified reference material. The presented procedure was successfully applied to the separation-preconcentration and determination of iron and lead content of some natural water and herbal plant samples from Kayseri, Turkey.

Plastron properties of a superhydrophobic surface

NASA Astrophysics Data System (ADS)

Shirtcliffe, Neil J.; McHale, Glen; Newton, Michael I.; Perry, Carole C.; Pyatt, F. Brian

2006-09-01

Most insects and spiders drown when submerged during flooding or tidal inundation, but some are able to survive and others can remain submerged indefinitely without harm. Many achieve this by natural adaptations to their surface morphology to trap films of air, creating plastrons which fix the water-vapor interface and provide an incompressible oxygen-carbon dioxide exchange surface. Here the authors demonstrate how the surface of an extremely water-repellent foam mimics this mechanism of underwater respiration and allows direct extraction of oxygen from aerated water. The biomimetic principle demonstrated can be applied to a wide variety of man-made superhydrophobic materials.

Treatment wetlands in decentralised approaches for linking sanitation to energy and food security.

PubMed

Langergraber, Guenter; Masi, Fabio

2018-02-01

Treatment wetlands (TWs) are engineered systems that mimic the processes in natural wetlands with the purpose of treating contaminated water. Being a simple and robust technology, TWs are applied worldwide to treat various types of water. Besides treated water for reuse, TWs can be used in resources-oriented sanitation systems for recovering nutrients and carbon, as well as for growing biomass for energy production. Additionally, TWs provide a large number of ecosystem services. Integrating green infrastructure into urban developments can thus facilitate circular economy approaches and has positive impacts on environment, economy and health.

Locally Grown, Natural Ingredients? The Isotope Ratio Can Reveal a Lot!

PubMed

Rossier, Joël S; Maury, Valérie; Pfammatter, Elmar

2016-01-01

This communication gives an overview of selected isotope analyses applied to food authenticity assessment. Different isotope ratio detection technologies such as isotope ratio mass spectrometry (IRMS) and cavity ring down spectroscopy (CRDS) are briefly described. It will be explained how δ(18)O of water contained in fruits and vegetables can be used to assess their country of production. It will be explained why asparagus grown in Valais, in the centre of the Alps carries much less heavy water than asparagus grown closer to the sea coast. On the other hand, the use of δ(13)C can reveal whether a product is natural or adulterated. Applications including honey or sparkling wine adulteration detection will be briefly presented.

Generation of Hot Water from Hot-Dry for Heavy-Oil Recovery in Northern Alberta, Canada

NASA Astrophysics Data System (ADS)

Pathak, V.; Babadagli, T.; Majorowicz, J. A.; Unsworth, M. J.

2011-12-01

The focus of prior applications of hot-dry-rock (HDR) technology was mostly aimed at generating electricity. In northern Alberta, the thermal gradient is low and, therefore, this technology is not suitable for electricity generation. On the other hand, the cost of steam and hot water, and environmental impacts, are becoming critical issues in heavy-oil and bitumen recovery in Alberta. Surface generation of steam or hot-water accounts for six percent of Canada's natural gas consumption and about 50 million tons of CO2 emission. Lowered cost and environmental impacts are critical in the widespread use of steam (for in-situ recovery) and hot-water (for surface extraction of bitumen) in this region. This paper provides an extensive analysis of hot-water generation to be used in heavy-oil/bitumen recovery. We tested different modeling approaches used to determine the amount of energy produced during HDR by history matching to example field data. The most suitable numerical and analytical models were used to apply the data obtained from different regions containing heavy-oil/bitumen deposits in northern Alberta. The heat generation capacity of different regions was determined and the use of this energy (in the form of hot-water) for surface extraction processes was evaluated. Original temperature gradients were applied as well as realistic basement formation characteristics through an extensive hydro thermal analysis in the region including an experimental well drilled to the depth of 2,500m. Existing natural fractures and possible hydraulic fracturing scenarios were evaluated from the heat generation capacity and the economics points of view. The main problem was modeling difficulties, especially determination and representation of fracture network characteristics. A sensitivity analysis was performed for the selected high temperature gradient regions in Alberta. In this practice, the characteristics of hydraulic fractures, injection rate, depth, the distance between injection and production wells and formation thickness were used as variables and an optimization study was carried out based on these variables. The results showed that the hot water (50 C at surface) needed in Fort McMurray for extraction could be obtained at lower costs than the generation of it using natural gas.

Remote sensing applied in natural hazards mitigation - experiences from the international UNESCO/IUGS GARS-Program 1984 - 2002

NASA Astrophysics Data System (ADS)

Bannert, D.

Worldwide resources of arable land, water, groundwater, forest and expanding human habitat are under increasing pressure almost anywhere. Especially the non- industrialised countries with their rapidly increasing population are facing severe problems from natural catastrophes such as landslides, volcanic and seismic hazards, soil degradation and shortage of water or flooding. Geo-environmental research can help to identify the causes for these events, define the rehabilitation and can lead to early warning systems. Remote sensing adds considerable knowledge by providing a wide variety of sensors applied form airborne and space platforms, the data of which, once analysed, can provide completely new observations on natural risk areas. The UNESCO/IUGS sponsored GARS Program since 1984 is conducting- joint research with institutions in industrialised and developing countries. As of today, more than 40 institutes and individuals worldwide have joined the GARS- Program. Results of their research are among others contributions toLandslide assessment qVolcanic risk qCoastal hazards qDesertification processes q Space organisations and financing institutions serving developing nations are requested to help to deploy new sensors to monitor geo-dynamic processes, providing free and direct data reception in all parts of the world in order to allow national institutes to develop their own early warning capabilities.

Efficacy of hybrid adsorption/membrane pretreatment for low pressure membrane.

PubMed

Malczewska, B; Benjamin, M M

2016-08-01

Fouling by natural organic matter (NOM) is a major obstacle when water from natural sources is treated using low-pressure membranes. Prior research by our group has demonstrated that passing natural water through a thin, pre-deposited layer of heated aluminum oxide particles (HAOPs) can remove substantial amounts of NOM from the feed and thereby reduce the fouling rate of downstream membranes. The work reported here explored the technical efficacy of such a pretreatment process under more challenging (and therefore realistic) conditions than reported earlier. Several analytical techniques were applied to the feed and permeate in an attempt to identify the key fouling components. The results demonstrate that a HAOPs layer can be pre-deposited on a stainless steel mesh and then be readily washed off at the end of a filtration cycle with very little irreversible fouling due to residual NOM or HAOPs left on the mesh. In addition, the pretreatment step removes enough foulant to allow a downstream UF membrane to operate at significantly higher fluxes than when conventional pretreatment is applied. HAOPs pretreatment also reduced the formation of chlorinated and brominated trihalomethanes (THM4) by more than 67% and of haloacetic acids (HAA9) by 64%-88% in simulated distribution system (SDS) tests. Copyright © 2016 Elsevier Ltd. All rights reserved.

Restoring Natural Streamflow Variability by Modifying Multi-purpose Reservoir Operation

NASA Astrophysics Data System (ADS)

Shiau, J.

2010-12-01

Multi-purpose reservoirs typically provide benefits of water supply, hydroelectric power, and flood mitigation. Hydroelectric power generations generally do not consume water. However, temporal distribution of downstream flows is highly changed due to hydro-peaking effects. Associated with offstream diversion of water supplies for municipal, industrial, and agricultural requirements, natural streamflow characteristics of magnitude, duration, frequency, timing, and rate of change is significantly altered by multi-purpose reservoir operation. Natural flow regime has long been recognized a master factor for ecosystem health and biodiversity. Restoration of altered flow regime caused by multi-purpose reservoir operation is the main objective of this study. This study presents an optimization framework that modifying reservoir operation to seeking balance between human and environmental needs. The methodology presented in this study is applied to the Feitsui Reservoir, located in northern Taiwan, with main purpose of providing stable water-supply and auxiliary purpose of electricity generation and flood-peak attenuation. Reservoir releases are dominated by two decision variables, i.e., duration of water releases for each day and percentage of daily required releases within the duration. The current releasing policy of the Feitsui Reservoir releases water for water-supply and hydropower purposes during 8:00 am to 16:00 pm each day and no environmental flows releases. Although greater power generation is obtained by 100% releases distributed within 8-hour period, severe temporal alteration of streamflow is observed downstream of the reservoir. Modifying reservoir operation by relaxing these two variables and reserve certain ratio of streamflow as environmental flow to maintain downstream natural variability. The optimal reservoir releasing policy is searched by the multi-criterion decision making technique for considering reservoir performance in terms of shortage ratio and power generation and downstream hydrologic alterations in terms of ecological relevant indicators. The results show that the proposed methodology can mitigate hydro-peaking effects on natural variability, while maintains efficient reservoir operation.

Coal-derived humus: plant growth effects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Freeman, P.G.; Fowkes, W.W.

The growth-promoting properties of coal-derived humus were tested by a variety of bioassay methods. Humate materials used included leonardite, a form of naturally oxidized lignite, and humic acids extracted from leonardite. It was found that the greatest effects were evident when water-soluble humic acid was applied to excised root tips. No significant short-term effect was noted when water-soluble humic acid was applied to stem or coleoptile sections. Root initiation was promoted in bean stems when high concentrations of coal-derived humate were applied. Gross weight of tomato plants was increased by up to 40 percent when coal-derived humates were added inmore » concentrations of 10/sup 1/ to 10/sup 4/ ppM to the nutrient in a hydroponic growth test of 6 weeks' duration. It is concluded that coal-derived humate promotes the uptake of minerals, specifically iron, by serving as a metal chelate.« less

Comparative Hydrology, Water Quality, and Ecology of Selected Natural and Augmented Freshwater Wetlands in West-Central Florida

USGS Publications Warehouse

Lee, T.M.; Haag, K.H.; Metz, P.A.; Sacks, L.A.

2009-01-01

Comparing altered wetlands to natural wetlands in the same region improves the ability to interpret the gradual and cumulative effects of human development on freshwater wetlands. Hydrologic differences require explicit attention because they affect nearly all wetland functions and are an overriding influence on other comparisons involving wetland water quality and ecology. This study adopts several new approaches to quantify wetland hydrologic characteristics and then describes and compares the hydrology, water quality, and ecology of 10 isolated freshwater marsh and cypress wetlands in the mantled karst landscape of central Florida. Four of the wetlands are natural, and the other six have water levels indirectly lowered by ground-water withdrawals on municipally owned well fields. For several decades, the water levels in four of these altered wetlands have been raised by adding ground water in a mitigation process called augmentation. The two wetlands left unaugmented were impaired because their water levels were lowered. Multifaceted comparisons between the altered and natural wetlands are used to examine differences between marshes and cypress wetlands and to describe the effects of augmentation practices on the wetland ecosystems. In the karstic geologic setting, both natural and altered wetlands predominantly lost water to the surficial aquifer. Water leaking out of the wetlands created water-table mounds below the wetlands. The smallest mounds radiated only slightly beyond the vegetated area of the wetlands. The largest and steepest mounds occurred below two of the augmented wetlands. There, rapid leakage rates regenerated a largely absent surficial aquifer and mounds encompassed areas 7-8 times as large as the wetlands. Wetland leakage rates, estimated using a daily water-budget analysis applied over multiple years and normalized as inches per day, varied thirtyfold from the slowest leaking natural wetland to the fastest leaking augmented wetland. Leakage rates increased as the size of the flooded area decreased and as the downward head difference between the wetland and the underlying Upper Floridan aquifer increased. Allowing one of the augmented wetlands to dry up for about 2.5 months in the spring of 2004, and then refilling it, generated a net savings of augmentation water despite the amount of water required to recreate the water-table mound beneath the wetland. Runoff from the surrounding uplands was an important component of the water budget in all of the unaugmented wetlands and two of the augmented wetlands. At a minimum, runoff contributed from half (45 percent) to twice (182 percent) as much water as direct rainfall at individual wetlands. Wetland flooded areas, derived using wetland water levels and bathymetric data and presented as a percentage of total wetland area, were used to compare and contrast hydrologic conditions among the 10 wetlands. The percentages of the natural wetland areas that flooded during the study were comparable, despite differences in the sizes of the wetlands. The percent flooded area in each wetland was calculated daily over the study period and monthly for up to 16 years using historical water-level data. Historical flooding in the natural wetlands spanned a greater range in area and had more pronounced seasonality than historical flooding at either the impaired or augmented wetlands. Flooding in the impaired and natural wetlands was similar, however, during 2 years of the study with substantially reduced well-field pumping and above average rainfall. Comparisons indicated several hydrologic differences between the marsh and cypress wetlands in this study. The natural and impaired marshes leaked at about half the rate of the natural and impaired cypress wetlands, and the marshes collectively were underlain by geologic material with lower vertical leakance values than the cypress wetlands. The natural marshes had higher evaporation rates compared to cypress

Natural attenuation of metals and radionuclides: Report from a workshop held by Sandia National Laboratories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brady, P.V.; Borns, D.J.

1997-11-01

Natural attenuation is increasingly applied to remediate contaminated soils and ground waters. Roughly 25% of Superfund groundwater remedies in 1995 involved some type of monitored natural attenuation, compared to almost none 5 years ago. Remediation by natural attenuation (RNA) requires clear evidence that contaminant levels are decreasing sufficiently over time, a defensible explanation of the attenuation mechanism, long-term monitoring, and a contingency plan at the very least. Although the primary focus of implementation has to date been the biodegradation of organic contaminants, there is a wealth of scientific evidence that natural processes reduce the bioavailability of contaminant metals and radionuclides.more » Natural attenuation of metals and radionuclides is likely to revolve around sorption, solubility, biologic uptake and dilution controls over contaminant availability. Some of these processes can be applied to actively remediate sites. Others, such as phytoremediation, are likely to be ineffective. RNA of metals and radionuclides is likely to require specialized site characterization to construct contaminant and site-specific conceptual models of contaminant behavior. Ideally, conceptual models should be refined such that contaminant attenuation can be confidently predicted into the future. The technical approach to RNA of metals and radionuclides is explored here.« less

An assessment of rangeland activities on wildlife populations and habitats [Chapter 6

Treesearch

Paul R. Krausman; Vernon C. Bleich; William M. Block; David E. Naugle; Mark C. Wallace

2011-01-01

Numerous management practices are applied to rangelands in the western United States to enhance wildlife, including prescribed grazing, burning, brush management, mowing, fencing, land clearing, planting, and restoration to benefit soil and water. indeed, the natural resources conservation service (NRCS) lists 167 conservation practices (http://www.nrcs.usda.gov/...

A Regional Training Course in Natural Resources Management and Environmental Monitoring in Humid-Tropical Ecosystems.

ERIC Educational Resources Information Center

Ffolliott, Peter F.

Presented are the basic concepts, methods, and considerations relevant to formulating watershed resources goals, policies, and management practices. Intended primarily for resource managers and land use planners concerned with water resources, this regional training course manual emphasizes material which applies to humid and tropical ecosystems.…

Klamath Basin: A Watershed Approach to Support Habitat Restoration, Species Recovery, and Water Resource Planning

USGS Publications Warehouse

VanderKooi, S.P.; Thorsteinson, L.

2007-01-01

Water allocation among human and natural resource uses in the American West is challenging. Western rivers have been largely managed for hydropower, irrigation, drinking water, and navigation. Today land and water use practices have gained importance, particularly as aging dams are faced with re-licensing requirements and provisions of the Endangered Species and Clean Water Acts. Rising demand for scarce water heightens the need for scientific research to predict consequences of management actions on habitats, human resource use, and fish and wildlife. Climate change, introduction of invasive species, or restoration of fish passage can have large, landscape-scaled consequences - research must expand to encompass the appropriate scale and by applying multiple scientific disciplines to complex ecosystem challenges improve the adaptive management framework for decision-making.

Preparation of fungal conidia impacts their susceptibility to inactivation by ethanol vapours.

PubMed

Dao, Thien; Dantigny, Philippe

2009-11-15

A common protocol employed for the preparation of conidia employs flooding a fungal colony grown on semi-solid media under optimum conditions with an aqueous solution. In contrast, conidia produced in a natural environment are usually not hydrated when disseminated in air and can be produced under water stress. In order to simulate the latter conditions, cultures were grown at different water activities and conidia were dry-harvested on the lid by turning the dishes upside-down then gently tapping the bottom of the box. This study aimed at assessing the effect of the preparation of fungal conidia on their inactivation by ethanol vapours. Firstly ethanol vapours (either 0.30 or 0.45 kPa) were applied to conidia obtained from the standardised protocol and to dry-harvested conidia for some species of Penicillium. While all dry-harvested conidia remained viable after 24 h of treatment, about 1.0, 3.5 and 2.5 log(10) reductions were observed for hydrated conidia of Penicillium chrysogenum, Penicillium digitatum and Penicillium italicum respectively. Secondly ethanol vapours (0.67 kPa) were applied to dry-harvested conidia obtained from cultures grown at 0.99 a(w) and at reduced water activities. For all species, the susceptibility to ethanol vapours of conidia obtained at 0.99 a(w) was significantly greater than that of conidia obtained at reduced water activities. Conidia produced in a natural environment under non-optimal conditions would be much more resistant to ethanol vapours than those produced in the laboratory. This phenomenon may be due to a reduced intracellular water activity of dry-harvested conidia.

Dynamic water allocation policies improve the global efficiency of storage systems

NASA Astrophysics Data System (ADS)

Niayifar, Amin; Perona, Paolo

2017-06-01

Water impoundment by dams strongly affects the river natural flow regime, its attributes and the related ecosystem biodiversity. Fostering the sustainability of water uses e.g., hydropower systems thus implies searching for innovative operational policies able to generate Dynamic Environmental Flows (DEF) that mimic natural flow variability. The objective of this study is to propose a Direct Policy Search (DPS) framework based on defining dynamic flow release rules to improve the global efficiency of storage systems. The water allocation policies proposed for dammed systems are an extension of previously developed flow redistribution rules for small hydropower plants by Razurel et al. (2016).The mathematical form of the Fermi-Dirac statistical distribution applied to lake equations for the stored water in the dam is used to formulate non-proportional redistribution rules that partition the flow for energy production and environmental use. While energy production is computed from technical data, riverine ecological benefits associated with DEF are computed by integrating the Weighted Usable Area (WUA) for fishes with Richter's hydrological indicators. Then, multiobjective evolutionary algorithms (MOEAs) are applied to build ecological versus economic efficiency plot and locate its (Pareto) frontier. This study benchmarks two MOEAs (NSGA II and Borg MOEA) and compares their efficiency in terms of the quality of Pareto's frontier and computational cost. A detailed analysis of dam characteristics is performed to examine their impact on the global system efficiency and choice of the best redistribution rule. Finally, it is found that non-proportional flow releases can statistically improve the global efficiency, specifically the ecological one, of the hydropower system when compared to constant minimal flows.

Mycobacterium avium complex--the role of potable water in disease transmission.

PubMed

Whiley, H; Keegan, A; Giglio, S; Bentham, R

2012-08-01

Mycobacterium avium complex (MAC) is a group of opportunistic pathogens of major public health concern. It is responsible for a wide spectrum of disease dependent on subspecies, route of infection and patients pre-existing conditions. Presently, there is limited research on the incidence of MAC infection that considers both pulmonary and other clinical manifestations. MAC has been isolated from various terrestrial and aquatic environments including natural waters, engineered water systems and soils. Identifying the specific environmental sources responsible for human infection is essential in minimizing disease prevalence. This paper reviews current literature and case studies regarding the wide spectrum of disease caused by MAC and the role of potable water in disease transmission. Potable water was recognized as a putative pathway for MAC infection. Contaminated potable water sources associated with human infection included warm water distribution systems, showers, faucets, household drinking water, swimming pools and hot tub spas. MAC can maintain long-term contamination of potable water sources through its high resistance to disinfectants, association with biofilms and intracellular parasitism of free-living protozoa. Further research is required to investigate the efficiency of water treatment processes against MAC and into construction and maintenance of warm water distribution systems and the role they play in MAC proliferation. No claim to Australian Government works Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Microbiological Analysis in Three Diverse Natural Geothermal Bathing Pools in Iceland

PubMed Central

Thorolfsdottir, Berglind Osk Th.; Marteinsson, Viggo Thor

2013-01-01

Natural thermal bathing pools contain geothermal water that is very popular to bathe in but the water is not sterilized, irradiated or treated in any way. Increasing tourism in Iceland will lead to increasing numbers of bath guests, which can in turn affect the microbial flora in the pools and therefore user safety. Today, there is no legislation that applies to natural geothermal pools in Iceland, as the water is not used for consumption and the pools are not defined as public swimming pools. In this study, we conducted a microbiological analysis on three popular but different natural pools in Iceland, located at Lýsuhóll, Hveravellir and Landmannalaugar. Total bacterial counts were performed by flow cytometry, and with plate count at 22 °C, 37 °C and 50 °C. The presence of viable coliforms, Enterococcus spp. and pseudomonads were investigated by growth experiments on selective media. All samples were screened for noroviruses by real time PCR. The results indicate higher fecal contamination in the geothermal pools where the geothermal water flow was low and bathing guest count was high during the day. The number of cultivated Pseudomonas spp. was high (13,000–40,000 cfu/100 mL) in the natural pools, and several strains were isolated and classified as opportunistic pathogens. Norovirus was not detected in the three pools. DNA was extracted from one-liter samples in each pool and analyzed by partial 16S rRNA gene sequencing. Microbial diversity analysis revealed different microbial communities between the pools and they were primarily composed of alpha-, beta- and gammaproteobacteria. PMID:23493033

Conflicting Epistemologies and Inference in Coupled Human and Natural Systems

NASA Astrophysics Data System (ADS)

Garcia, M. E.

2017-12-01

Last year, I presented a model that projects per capita water consumption based on changes in price, population, building codes, and water stress salience. This model applied methods from hydrological science and engineering to relationships both within and beyond their traditional scope. Epistemologically, the development of mathematical models of natural or engineered systems is objectivist while research examining relationships between observations, perceptions and action is commonly constructivist or subjectivist. Drawing on multiple epistemologies is common in, and perhaps central to, the growing fields of coupled human and natural systems, and socio-hydrology. Critically, these philosophical perspectives vary in their view of the nature of the system as mechanistic, adaptive or constructed, and the split between aleatory and epistemic uncertainty. Interdisciplinary research is commonly cited as a way to address the critical and domain crossing challenge of sustainability as synthesis across perspectives can offer a more comprehensive view of system dynamics. However, combining methods and concepts from multiple ontologies and epistemologies can introduce contradictions into the logic of inference. These contractions challenge the evaluation of research products and the implications for practical application of research findings are not fully understood. Reflections on the evaluation, application, and generalization of the water consumption model described above are used to ground these broader questions and offer thoughts on the way forward.

Oxidative elimination of cyanotoxins: comparison of ozone, chlorine, chlorine dioxide and permanganate.

PubMed

Rodríguez, Eva; Onstad, Gretchen D; Kull, Tomas P J; Metcalf, James S; Acero, Juan L; von Gunten, Urs

2007-08-01

As the World Health Organization (WHO) progresses with provisional Drinking Water Guidelines of 1 microg/L for microcystin-LR and a proposed Guideline of 1 microg/L for cylindrospermopsin, efficient treatment strategies are needed to prevent cyanotoxins such as these from reaching consumers. A kinetic database has been compiled for the oxidative treatment of three cyanotoxins: microcystin-LR (MC-LR), cylindrospermopsin (CYN), and anatoxin-a (ANTX) with ozone, chlorine, chlorine dioxide and permanganate. This kinetic database contains rate constants not previously reported and determined in the present work (e.g. for permanganate oxidation of ANTX and chlorine dioxide oxidation of CYN and ANTX), together with previously published rate constants for the remaining oxidation processes. Second-order rate constants measured in pure aqueous solutions of these toxins could be used in a kinetic model to predict the toxin oxidation efficiency of ozone, chlorine, chlorine dioxide and permanganate when applied to natural waters. Oxidants were applied to water from a eutrophic Swiss lake (Lake Greifensee) in static-dose testing and dynamic time-resolved experiments to confirm predictions from the kinetic database, and to investigate the effects of a natural matrix on toxin oxidation and by-product formation. Overall, permanganate can effectively oxidize ANTX and MC-LR, while chlorine will oxidize CYN and MC-LR and ozone is capable of oxidizing all three toxins with the highest rate. The formation of trihalomethanes (THMs) in the treated water may be a restriction to the application of sufficiently high-chlorine doses.

Experimental determination of forces applied by liquid water drops at high drop velocities impacting a glass plate with and without a shallow water layer using wavelet deconvolution

NASA Astrophysics Data System (ADS)

Yu, Y.; Hopkins, C.

2018-05-01

Time-dependent forces applied by 2 and 4.5 mm diameter drops of water (with velocities up to terminal velocity) impacting upon a glass plate with or without a water layer (up to 10 mm depth) have been measured using two different approaches, force transduction and wavelet deconvolution. Both approaches are in close agreement for drops falling on dry glass. However, only the wavelet approach is able to measure natural features of the splash on shallow water layers that impart forces to the plate after the initial impact. At relatively high velocities (including terminal velocity) the measured peak force from the initial impact is significantly higher than that predicted by idealised drop shape models and models from Roisman et al. and Marengo et al. Hence empirical formulae are developed for the initial time-dependent impact force from drops falling at (a) different velocities up to and including terminal velocity onto a dry glass surface, (b) terminal velocity onto dry glass or glass with a water layer and (c) different velocities below terminal velocity onto dry glass or glass with a water layer. For drops on dry glass, the empirical formulae are applicable to a glass plate or a composite layered plate with a glass surface, although they apply to other plate thicknesses and are applicable to any plate material with a similar surface roughness and wettability. The measurements also indicate that after the initial impact there can be high level forces when bubbles are entrained in the water layer.

Framework for measuring sustainable development in catchment systems.

PubMed

Walmsley, Jay J

2002-02-01

Integrated catchment management represents an approach to managing the resources of a catchment by integrating environmental, economic, and social issues. It is aimed at deriving sustainable benefits for future generations, while protecting natural resources, particularly water, and minimizing possible adverse social, economic, and environmental consequences. Indicators of sustainable development, which summarize information for use in decision-making, are invaluable when trying to assess the diverse, interacting components of catchment processes and resource management actions. The Driving-Forces--Pressure--State--Impact--Response (DPSIR) indicator framework is useful for identifying and developing indicators of sustainable development for catchment management. Driving forces have been identified as the natural conditions occurring in a catchment and the level of development and economic activity. Pressures include the natural and anthropogenic supply of water, water demand, and water pollution. State indicators can be split into those of quantity and those of quality. Impacts include those that affect the ecosystems directly and those that impact the use value of the resource. It core indicators are identified within each of the categories given in the framework, most major catchment-based management issues can be evaluated. This framework is applied to identify key issues in catchment management in South Africa, and develop a set of indicators for evaluating catchments throughout the country.

Peak water limits to freshwater withdrawal and use

PubMed Central

Gleick, Peter H.; Palaniappan, Meena

2010-01-01

Freshwater resources are fundamental for maintaining human health, agricultural production, economic activity as well as critical ecosystem functions. As populations and economies grow, new constraints on water resources are appearing, raising questions about limits to water availability. Such resource questions are not new. The specter of “peak oil”—a peaking and then decline in oil production—has long been predicted and debated. We present here a detailed assessment and definition of three concepts of “peak water”: peak renewable water, peak nonrenewable water, and peak ecological water. These concepts can help hydrologists, water managers, policy makers, and the public understand and manage different water systems more effectively and sustainably. Peak renewable water applies where flow constraints limit total water availability over time. Peak nonrenewable water is observable in groundwater systems where production rates substantially exceed natural recharge rates and where overpumping or contamination leads to a peak of production followed by a decline, similar to more traditional peak-oil curves. Peak “ecological” water is defined as the point beyond which the total costs of ecological disruptions and damages exceed the total value provided by human use of that water. Despite uncertainties in quantifying many of these costs and benefits in consistent ways, more and more watersheds appear to have already passed the point of peak water. Applying these concepts can help shift the way freshwater resources are managed toward more productive, equitable, efficient, and sustainable use. PMID:20498082

Toward an Economic Definition of Sustainable Yield for Coastal Aquifers

NASA Astrophysics Data System (ADS)

Jenson, J. W.; Habana, N. C.; Lander, M.

2016-12-01

The concept of aquifer sustainable yield has long been criticized, debated, and even disparaged among groundwater hydrologists, but policy-makers and professional water resource managers inevitably ask them for unequivocal answers to such questions as "What is the absolute maximum volume of water that could be sustainably withdrawn from this aquifer?" We submit that it is therefore incumbent upon hydrologists to develop and offer valid practical definitions of sustainable yield that can be usefully applied to given conditions and types of aquifers. In coastal aquifers, water quality—in terms of salinity—is affected by changes in the natural water budget and the volume rate of artificial extraction. In principle, one can identify a family of assay curves for a given aquifer, showing the specific relationships between the quantity and quality of the water extracted under given conditions of recharge. The concept of the assay curve, borrowed from the literature of natural-resource extraction economics, has to our knowledge not yet found its way into the literature of applied hydrology. The relationships between recharge, extraction, and water quality that define the assay curve can be determined empirically from sufficient observations of groundwater response to recharge and extraction and can be estimated from models that have been reliably history-matched ("calibrated") to such data. We thus propose a working definition of sustainable yield for coastal aquifers in terms of the capacity that ultimately could be achieved by an ideal production system, given what is known or can be assumed about the natural limiting conditions. Accordingly, we also offer an approach for defining an ideal production system for a given aquifer, and demonstrate how observational data and/or modeling results can be used to develop assay curves of quality vs. quantity extracted, which can serve as reliable predictive tools for engineers, managers, regulators, and policy-makers interested in sustainable management of groundwater from coastal aquifers. Such tools can provide scientifically valid baselines against which to make informed economic evaluations of future options for holistic sustainable management of coastal aquifers.

Overview of groundwater management approaches at salinisation risk

NASA Astrophysics Data System (ADS)

Polemio, Maurizio; Zuffianò, Livia Emanuela

2013-04-01

All natural waters contain dissolved minerals from interactions with atmospheric and soil gases, mixing with other solutions, and/or interactions with the biosphere and lithosphere. In many cases, these processes result in natural waters containing solute or salinity above concentrations recommended for a specified use, which creates significant social and economic problems. Groundwater salinisation can be caused by natural phenomena and anthropogenic activities. For the former case, we can distinguish terrestrial and marine phenomena. Approximately 16% of the total area of continental earth is potentially involved in groundwater salinisation. Seawater intrusion can be considered to be the primary phenomenon to be studied in terms of groundwater salinisation. Three schematic approaches to the protection of groundwater via salinisation mitigation and/or groundwater salinity improvement are described based on the classifications of the primary salinisation sources and focusing on the effect of seawater intrusion. The complexity of these approaches generally increases due to difficulties caused by groundwater quality and quantity degradation and increased demand for quality water. In order from the lowest to the highest complexity, these approaches are the engineering approach, the discharge management approach, and the water and land management approach. The engineering approach is realised on the local or detailed scale with the purpose of controlling the salinisation, optimising the well discharge with specific technical solutions and/or completing works to improve the quality and/or quantity of the discharged fresh groundwater. The discharge management approach encompasses at least an entire coastal aquifer and defines rules concerning groundwater utilisation and well discharge. The water and land management approach should be applied on the regional scale. Briefly, this approach becomes necessary when one or more need creates an overall framework of high-quality water scarcity. These conditions, sometimes combined with an awareness of negative environmental effects, force people to accept new water saving practices and land use modifications. As the natural effects of salinisation can be enhanced by a multiplicity of human actions, the discharge management approach and the water and land management approach should generally be applied by water authorities or institutional and governmental organisations that are responsible for groundwater quality and availability. The practical study of Apulian karstic coastal aquifers is discussed in detail. Previously experienced management difficulties are described, as well as a proposed multi-methodological approach based on monitoring networks, the spatiotemporal analysis of groundwater quality changes, and multiparameter well logging. The core of this approach is the definition of the salinity threshold value between pure fresh groundwater and any fresh and saline groundwater mixture. The basic or single tools were defined to be simple, quick and cost-effective to be applicable to the widest range of situations.

Evaluating the impact of irrigation on surface water - groundwater interaction and stream temperature in an agricultural watershed.

PubMed

Essaid, Hedeff I; Caldwell, Rodney R

2017-12-01

Changes in groundwater discharge to streams caused by irrigation practices can influence stream temperature. Observations along two currently flood-irrigated reaches in the 640-square-kilometer upper Smith River watershed, an important agricultural and recreational fishing area in west-central Montana, showed a downstream temperature decrease resulting from groundwater discharge to the stream. A watershed-scale coupled surface water and groundwater flow model was used to examine changes in streamflow, groundwater discharge to the stream and stream temperature resulting from irrigation practices. The upper Smith River watershed was used to develop the model framework including watershed climate, topography, hydrography, vegetation, soil properties and current irrigation practices. Model results were used to compare watershed streamflow, groundwater recharge, and groundwater discharge to the stream for three scenarios: natural, pre-irrigation conditions (PreIrr); current irrigation practices involving mainly stream diversion for flood and sprinkler irrigation (IrrCurrent); and a hypothetical scenario with only groundwater supplying sprinkler irrigation (IrrGW). Irrigation increased groundwater recharge relative to natural PreIrr conditions because not all applied water was removed by crop evapotranspiration. Groundwater storage and groundwater discharge to the stream increased relative to natural PreIrr conditions when the source of irrigation water was mainly stream diversion as in the IrrCurrent scenario. The hypothetical IrrGW scenario, in which groundwater withdrawals were the sole source of irrigation water, resulted in widespread lowering of the water table and associated decreases in groundwater storage and groundwater discharge to the stream. A mixing analysis using model predicted groundwater discharge along the reaches suggests that stream diversion and flood irrigation, represented in the IrrCurrent scenario, has led to cooling of stream temperatures relative to natural PreIrr conditions improving fish thermal habitat. However, the decrease in groundwater discharge in the IrrGW scenario resulting from large-scale groundwater withdrawal for irrigation led to warmer than natural stream temperatures and possible degradation of fish habitat. Published by Elsevier B.V.

Evaluating the impact of irrigation on surface water – groundwater interaction and stream temperature in an agricultural watershed

USGS Publications Warehouse

Essaid, Hedeff I.; Caldwell, Rodney R.

2017-01-01

Changes in groundwater discharge to streams caused by irrigation practices can influence stream temperature. Observations along two currently flood-irrigated reaches in the 640-square-kilometer upper Smith River watershed, an important agricultural and recreational fishing area in west-central Montana, showed a downstream temperature decrease resulting from groundwater discharge to the stream. A watershed-scale coupled surface water and groundwater flow model was used to examine changes in streamflow, groundwater discharge to the stream and stream temperature resulting from irrigation practices. The upper Smith River watershed was used to develop the model framework including watershed climate, topography, hydrography, vegetation, soil properties and current irrigation practices. Model results were used to compare watershed streamflow, groundwater recharge, and groundwater discharge to the stream for three scenarios: natural, pre-irrigation conditions (PreIrr); current irrigation practices involving mainly stream diversion for flood and sprinkler irrigation (IrrCurrent); and a hypothetical scenario with only groundwater supplying sprinkler irrigation (IrrGW). Irrigation increased groundwater recharge relative to natural PreIrr conditions because not all applied water was removed by crop evapotranspiration. Groundwater storage and groundwater discharge to the stream increased relative to natural PreIrr conditions when the source of irrigation water was mainly stream diversion as in the IrrCurrent scenario. The hypothetical IrrGW scenario, in which groundwater withdrawals were the sole source of irrigation water, resulted in widespread lowering of the water table and associated decreases in groundwater storage and groundwater discharge to the stream. A mixing analysis using model predicted groundwater discharge along the reaches suggests that stream diversion and flood irrigation, represented in the IrrCurrent scenario, has led to cooling of stream temperatures relative to natural PreIrr conditions improving fish thermal habitat. However, the decrease in groundwater discharge in the IrrGW scenario resulting from large-scale groundwater withdrawal for irrigation led to warmer than natural stream temperatures and possible degradation of fish habitat.

Framework for a ground-water quality monitoring and assessment program for California

USGS Publications Warehouse

Belitz, Kenneth; Dubrovsky, Neil M.; Burow, Karen; Jurgens, Bryant C.; John, Tyler

2003-01-01

The State of California uses more ground water than any other State in the Nation. With a population of over 30 million people, an agricultural economy based on intensive irrigation, large urban industrial areas, and naturally elevated concentrations of some trace elements, there is a wide range of contaminant sources that have the potential to contaminate ground water and limit its beneficial uses. In response to the many-and different-potential sources of ground-water contamination, the State of California has evolved an extensive set of rules and programs to protect ground-water quality, and agencies to implement the rules and programs. These programs have in common a focus on compliance with regulations governing chemical use and (or) ground-water quality. Although appropriate for, and successful at, their specific missions, these programs do not at present provide a comprehensive view of ground-water quality in the State of California. In October 2001, The California Assembly passed a bill, AB 599, establishing the Ground-Water- Quality Monitoring Act of 2001.' The goal of AB 599 is to improve Statewide comprehensive ground-water monitoring and increase availability of information about ground-water quality to the public. AB 599 requires the State Water Resources Control Board (SWRCB), in collaboration with an interagency task force (ITF) and a public advisory committee (PAC), to develop a plan for a comprehensive ground-water monitoring program. AB 599 specifies that the comprehensive program should be capable of assessing each ground-water basin in the State through direct and other statistically reliable sampling approaches, and that the program should integrate existing monitoring programs and design new program elements, as necessary. AB 599 also stresses the importance of prioritizing ground-water basins that provide drinking water. The United States Geological Survey (USGS), in cooperation with the SWRCB, and in coordination with the ITF and PAC, has developed a framework for a comprehensive ground-water-quality monitoring and assessment program for California. The proposed framework relies extensively on previous work conducted by the USGS through its National Water-Quality Assessment (NAWQA) program. In particular, the NAWQA program defines three types of ground-water assessment: (1) status, the assessment of the current quality of the ground-water resource; (2) trends, the detection of changes in water quality, and (3) understanding, assessing the human and natural factors that affect ground-water quality. A Statewide, comprehensive ground-water quality-monitoring and assessment program is most efficiently accomplished by applying uniform and consistent study-design and data-collection protocols to the entire State. At the same time, a comprehensive program should be relevant at a variety of scales, and therefore needs to retain flexibility to address regional and local issues. Consequently, many of the program components include a predominant element that will be consistently applied in all basins, and a secondary element that may be applied in specific basins where local conditions warrant attention.

Negotiation techniques to resolve western water disputes

USGS Publications Warehouse

Lamb, Berton L.; Taylor, Jonathan G.

1990-01-01

There is a growing literature on the resolution of natural resources conflicts. Much of it is practical, focusing on guidelines for hands-on negotiation. This literature can be a guide in water conflicts. This is especially true for negotiations over new environmental values such as instream flow. The concepts of competitive, cooperative, and integrative styles of conflict resolution are applied to three cases of water resource bargaining. Lessons for the effective use of these ideas include: break a large number of parties into small working groups, approach value differences in small steps, be cautious in the presence of an attentive public, keeps decisions at the local level, and understand the opponent's interests.

Theoretical study of optical activity of 1:1 hydrogen bond complexes of water with S-warfarin

NASA Astrophysics Data System (ADS)

Dadsetani, Mehrdad; Abdolmaleki, Ahmad; Zabardasti, Abedin

2016-11-01

The molecular interaction between S-warfarin (SW) and a single water molecule was investigated using the B3LYP method at 6-311 ++G(d,p) basis set. The vibrational spectra of the optimized complexes have been investigated for stabilization checking. Quantum theories of atoms in molecules, natural bond orbitals, molecular electrostatic potentials and energy decomposition analysis methods have been applied to analyze the intermolecular interactions. The intermolecular charge transfer in the most stable complex is in the opposite direction from those in the other complexes. The optical spectra and the hyperpolarizabilities of SW-water hydrogen bond complexes have been computed.

Langley's DEVELOP Team Applies NASA's Earth Observations to Address Environmental Issues Across the Country and Around the Globe

NASA Technical Reports Server (NTRS)

Childs, Lauren M.; Miller, Joseph E.

2011-01-01

The DEVELOP National Program was established over a decade ago to provide students with experience in the practical application of NASA Earth science research results. As part of NASA's Applied Sciences Program, DEVELOP focuses on bridging the gap between NASA technology and the public through projects that innovatively use NASA Earth science resources to address environmental issues. Cultivating a diverse and dynamic group of students and young professionals, the program conducts applied science research projects during three terms each year (spring, summer, and fall) that focus on topics ranging from water resource management to natural disasters.

An Object-Based Machine Learning Classification Procedure for Mapping Impoundments in Brazil's Amazon-Cerrado Agricultural Frontier

NASA Astrophysics Data System (ADS)

Solvik, K.; Macedo, M.; Graesser, J.; Lathuilliere, M. J.

2017-12-01

Large-scale agriculture and cattle ranching in Brazil has driving the creation of tens of thousands of small stream impoundments to provide water for crops and livestock. These impoundments are a source of methane emissions and have significant impacts on stream temperature, connectivity, and water use over a large region. Due to their large numbers and small size, they are difficult to map using conventional methods. Here, we present a two-stage object-based supervised classification methodology for identifying man-made impoundments in Brazil. First, in Google Earth Engine pixels are classified as water or non-water using satellite data and HydroSHEDS products as predictors. Second, using Python's scikit-learn and scikit-image modules the water objects are classified as man-made or natural based on a variety of shape and spectral properties. Both classifications are performed by a random forest classifier. Training data is acquired by visually identifying impoundments and natural water bodies using high resolution satellite imagery from Google Earth.This methodology was applied to the state of Mato Grosso using a cloud-free mosaic of Sentinel 1 (10m resolution) radar and Sentinel 2 (10-20m) multispectral data acquired during the 2016 dry season. Independent test accuracy was estimated at 95% for the first stage and 93% for the second. We identified 54,294 man-made impoundments in Mato Grosso in 2016. The methodology is generalizable to other high resolution satellite data and has been tested on Landsat 5 and 8 imagery. Applying the same approach to Landsat 8 images (30 m), we identified 35,707 impoundments in the 2015 dry season. The difference in number is likely because the coarser-scale imagery fails to detect small (< 900 m2) objects. On-going work will apply this approach to satellite time series for the entire Amazon-Cerrado frontier, allowing us to track changes in the number, size, and distribution of man-made impoundments. Automated impoundment mapping over large areas may help with management of streams in agricultural landscapes in Brazil and other tropical regions.

Seeding and fertilization effects on plant cover and community recovery following wildfire in the Eastern Cascade Mountains, USA

Treesearch

Erich Kyle Dodson; David W. Peterson

2009-01-01

Slope stabilization treatments are frequently applied following high severity wildfires to reduce erosion, protect water quality, and mitigate threats to human life and property. However, the effectiveness of many treatment options has not been well established. Furthermore, treatments may unintentionally inhibit natural vegetation recovery or facilitate exotic species...

21 CFR 114.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... following definitions apply. (a) Acid foods means foods that have a natural pH of 4.6 or below. (b... have a finished equilibrium pH of 4.6 or below. These foods may be called, or may purport to be... alcoholic beverages, with a finished equilibrium pH greater than 4.6 and a water activity (aw) greater than...

21 CFR 114.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... following definitions apply. (a) Acid foods means foods that have a natural pH of 4.6 or below. (b... have a finished equilibrium pH of 4.6 or below. These foods may be called, or may purport to be... alcoholic beverages, with a finished equilibrium pH greater than 4.6 and a water activity (aw) greater than...

Comparative study on major bioactive components in natural, artificial and in-vitro cultured Calculus Bovis.

PubMed

Yan, Shi-Kai; Wu, Yan-Wen; Liu, Run-Hui; Zhang, Wei-Dong

2007-01-01

Major bioactive components in various Calculus Bovis, including natural, artificial and in-vitro cultured Calculus Bovis, were comparatively studied. An approach of high-performance liquid chromatography coupled with ultraviolet and evaporative light scattering detections (HPLC/UV/ELSD) was established to simultaneously determinate six bioactive components thereof, including five bile acids (cholic acid, deoxycholic acid, ursodeoxycholic, chenodeoxycholic acid, hyodeoxycholic acid) and bilirubin. ELSD and UV detector were applied to detect bile acids and bilirubin respectively. The assay was performed on a C(18) column with water-acetonitrile gradient elution and the investigated constituents were authenticated by comparing retention times and mass spectra with those of reference compounds. The proposed method was applied to analyze twenty-one Calculus Bovis extraction samples, and produced data with acceptable linearity, precision, repeatability and accuracy. The result indicated the variations among Calculus Bovis samples under different developmental conditions. Artificial and in-vitro cultured Calculus Bovis, especially in-vitro cultured ones, which contain total bioactive constituents no less than natural products and have the best batch-to-batch uniformity, suffice to be used as substitutes of natural Calculus Bovis.

Involvement of cell shape and flagella in the bacterial retention during percolation of contaminated water through soil columns in tropical region.

PubMed

Nola, Moise; Ewoti, Olive V Noah; Nougang, Mireille; Moungang, Marlyse L; Chihib, Nour-Eddine; Krier, Francois; Servais, Pierre; Hornez, Jean-Pierre; Njine, Thomas

2010-09-01

Microorganisms' retention in soil contributes to the natural purification of groundwater. Bacteria found in groundwater are generally of various shapes. The aim of this study was to assess the importance of cell shape and flagella in bacterial retention during polluted water percolation through two soil columns CA and CB, in the equatorial region in Central Africa. Percolation tests were carried out using different water loads samples which were contaminated by Escherichia coli (straight rods, peritrichous flagella), Vibrio parahaemolyticus (rods bacteria, polar flagella), and Staphylococcus saprophyticus (spherical, free-flagellum). It has been noted that showed that through soil column CA, the mean values of cells retention ratios (T(R)) varied with bacteria species considered, and from one applied water load sample to another. E. coli T(R) and that of S. saprophyticus were not significantly different (P> 0.05) for the two soil columns. V. parahaemolyticus T(R) significantly differed from that of E. coli and S. saprophyticus through soil column CA (P< 0.01) when the highest water load was applied, and through soil column CB (P< 0.05) for each of water load applied. A relative hierarchical arrangement of retained cells based on the T(R) showed that V. parahaemolyticus was less retained through the 2 soil columns. S. saprophyticus in most cases was more retained than others. The physical properties of the bacterial cell must be taken into consideration when evaluating the transfer of bacteriological pollutants towards groundwater.

Stability of loess

USGS Publications Warehouse

Lutenegger, A.J.; Hallberg, G.R.

1988-01-01

Lutenegger, A.J. and Hallberg, G.R., 1988. Stability of loess. Eng. Geol., 25: 247-261. The natural stability of loess soils can be related to fundamental geotechnical properties such as Atterberg limits, water content and void ratio. Field observations of unstable conditions in loess deposits in the upper midwest, U.S.A. show relationships between instability and the in situ moisture content and the liquidity index of the loess. Unstable loess can attain natural moisture contents equal to, or greater than, its liquid limit. Implications of these observations for applied engineering works are described. ?? 1988.

Determination of background levels on water quality of groundwater bodies: a methodological proposal applied to a Mediterranean River basin (Guadalhorce River, Málaga, southern Spain).

PubMed

Urresti-Estala, Begoña; Carrasco-Cantos, Francisco; Vadillo-Pérez, Iñaki; Jiménez-Gavilán, Pablo

2013-03-15

Determine background levels are a key element in the further characterisation of groundwater bodies, according to Water Framework Directive 2000/60/EC and, more specifically, Groundwater Directive 2006/118/EC. In many cases, these levels present very high values for some parameters and types of groundwater, which is significant for their correct estimation as a prior step to establishing thresholds, assessing the status of water bodies and subsequently identifying contaminant patterns. The Guadalhorce River basin presents widely varying hydrogeological and hydrochemical conditions. Therefore, its background levels are the result of the many factors represented in the natural chemical composition of water bodies in this basin. The question of determining background levels under objective criteria is generally addressed as a statistical problem, arising from the many aspects involved in its calculation. In the present study, we outline the advantages of applying two statistical techniques applied specifically for this purpose: (1) the iterative 2σ technique and (2) the distribution function, and examine whether the conclusions reached by these techniques are similar or whether they differ considerably. In addition, we identify the specific characteristics of each approach and the circumstances under which they should be used. Copyright © 2012 Elsevier Ltd. All rights reserved.

Risk indicators for water supply systems for a drought Decision Support System in central Tuscany (Italy)

NASA Astrophysics Data System (ADS)

Rossi, Giuseppe; Garrote, Luis; Caporali, Enrica

2010-05-01

Identifying the occurrence, the extent and the magnitude of a drought can be delicate, requiring detection of depletions of supplies and increases in demand. Drought indices, particularly the meteorological ones, can describe the onset and the persistency of droughts, especially in natural systems. However they have to be used cautiously when applied to water supply systems. They show little correlation with water shortage situations, since water storage, as well as demand fluctuation, play an important role in water resources management. For that reason a more dynamic indicator relating supply and demand is required in order to identify situations when there is risk of water shortages. In water supply systems there is great variability on the natural water resources and also on the demands. These quantities can only be defined probabilistically. This great variability is faced defining some threshold values, expressed in probabilistic terms, that measure the hydrologic state of the system. They can identify specific actions in an operational context in different levels of severity, like the normal, pre-alert, alert and emergency scenarios. They can simplify the decision-making required during stressful periods and can help mitigate the impacts of drought by clearly defining the conditions requiring actions. The threshold values are defined considering the probability to satisfy a given fraction of the demand in a certain time horizon, and are calibrated through discussion with water managers. A simplified model of the water resources system is built to evaluate the threshold values and the management rules. The threshold values are validated with a long term simulation that takes into account the characteristics of the evaluated system. The levels and volumes in the different reservoirs are simulated using 20-30 years time series. The critical situations are assessed month by month in order to evaluate optimal management rules during the year and avoid conditions of total water shortage. The methodology is applied to the urban area Firenze-Prato-Pistoia in central Tuscany, in central Italy. The catchment of the investigated area has a surface of 1231 km2 and, accordingly to the census ISTAT 2001, 945˙972 inhabitants.

Folgen des Globalen Wandels für das Grundwasser in Süddeutschland - Teil 2: Sozioökonomische Aspekte

NASA Astrophysics Data System (ADS)

Barthel, Roland; Krimly, Tatjana; Elbers, Michael; Soboll, Anja; Wackerbauer, Johann; Hennicker, Rolf; Janisch, Stephan; Reichenau, Tim G.; Dabbert, Stephan; Schmude, Jürgen; Ernst, Andreas; Mauser, Wolfram

2011-12-01

In order to account for complex interactions between humans climate and the water cycle, the research consortium GLOWA-Danube (www.glowa-danube.de) has developed the simulation system DANUBIA which consists of 17 coupled models. DANUBIA was applied to investigate various impacts of global-change between 2011 and 2060 in the Upper Danube Catchment. This article describes part 2 of an article series with investigations of socio-economic aspects, while part 1 (Barthel et al. in Grundwasser 16(4), doi:10.1007/s007-011-01794, 2011) deals with natural-spatial aspects. The principles of socio-economic actor-modeling and interactions between socio-economic and natural science model components are described here. We present selected simulations that show impacts on groundwater from changes in agriculture, tourism, economy, domestic water users and water supply. Despite decreases in water consumption, the scenario simulations show significant decreases in groundwater quantity. On the other hand, groundwater quality will likely be influenced more severely by land use changes compared to direct climatic causes. However, overall changes will not be dramatic.

Determination of free Zn2+ concentration in synthetic and natural samples with AGNES (Absence of Gradients and Nernstian Equilibrium Stripping) and DMT (Donnan Membrane Technique).

PubMed

Chito, Diana; Weng, Liping; Galceran, Josep; Companys, Encarnació; Puy, Jaume; van Riemsdijk, Willem H; van Leeuwen, Herman P

2012-04-01

The determination of free Zn(2+) ion concentration is a key in the study of environmental systems like river water and soils, due to its impact on bioavailability and toxicity. AGNES (Absence of Gradients and Nernstian Equilibrium Stripping) and DMT (Donnan Membrane Technique) are emerging techniques suited for the determination of free heavy metal concentrations, especially in the case of Zn(2+), given that there is no commercial Ion Selective Electrode. In this work, both techniques have been applied to synthetic samples (containing Zn and NTA) and natural samples (Rhine river water and soils), showing good agreement. pH fluctuations in DMT and N(2)/CO(2) purging system used in AGNES did not affect considerably the measurements done in Rhine river water and soil samples. Results of DMT in situ of Rhine river water are comparable to those of AGNES in the lab. The comparison of this work provides a cross-validation for both techniques. Copyright © 2012 Elsevier B.V. All rights reserved.

Spectrophotometric determination of zinc and copper in a multi-syringe flow injection analysis system using a liquid waveguide capillary cell: application to natural waters.

PubMed

Páscoa, Ricardo N M J; Tóth, Ildikó V; Rangel, António O S S

2011-06-15

This work exploits a multi-syringe injection analysis (MSFIA) system coupled with a long liquid waveguide capillary cell for the spectrophotometric determination of zinc and copper in waters. A liquid waveguide capillary cell (1.0m pathlength, 550 μm i.d. and 250 μL internal volume) was used to enhance the sensitivity of the detection. The determination for both ions is based on a colorimetric reaction with zincon at different pH values. The developed methodology compares favourably with other previously described procedures, as it allows to reach low detection limits for both cations (LODs of 0.1 and 2 μg L(-1), for copper and zinc, respectively), without the need for any pre-concentration step. The system also provided a linear response up to 100 μg L(-1) with a high throughput (43 h(-1)) and low reagent consumption and effluent production. The developed work was applied to natural waters and three certified reference water samples. Copyright © 2011 Elsevier B.V. All rights reserved.

Water quality at a biosolids-application area near Deer Trail, Colorado, 1993-1999

USGS Publications Warehouse

Yager, Tracy J.B.

2014-01-01

The Metro Wastewater Reclamation District (Metro District) in Denver, Colo., applied biosolids resulting from municipal sewage treatment to farmland in eastern Colorado beginning in December 1993. In mid-1993, the U.S. Geological Survey in cooperation with the Metro District began monitoring water quality at the biosolids-application area about 10 miles east of Deer Trail, Colo., to evaluate baseline water quality and the combined effects of natural processes, land uses, and biosolids applications on water quality of the biosolids application area. Water quality was characterized by baseline and post-biosolids-application sampling for selected inorganic and bacteriological constituents during 1993 through 1998, with some additional specialized sampling in 1999. The study included limited sampling of surface water and the unsaturated zone, but primarily focused on groundwater. See report for complete abstract.

Microwave-Assisted Extraction of Fucoidan from Marine Algae.

PubMed

Mussatto, Solange I

2015-01-01

Microwave-assisted extraction (MAE) is a technique that can be applied to extract compounds from different natural resources. In this chapter, the use of this technique to extract fucoidan from marine algae is described. The method involves a closed MAE system, ultrapure water as extraction solvent, and suitable conditions of time, pressure, and algal biomass/water ratio. By using this procedure under the specified conditions, the penetration of the electromagnetic waves into the material structure occurs in an efficient manner, generating a distributed heat source that promotes the fucoidan extraction from the algal biomass.

Fowl play? Forensic environmental assessment of alleged discharge of highly contaminated effluent from a chicken slaughterhouse

NASA Astrophysics Data System (ADS)

Harvey, P.; Taylor, M. P.; Handley, H. K.

2016-12-01

Multiple lines of geochemical and biological evidence are applied to identify and fingerprint the nature and source of alleged contamination emanating from a chicken slaughterhouse on the urban fringe of Sydney, Australia. The slaughterhouse has a long history of alleged environmental misconduct. The impact of the facility on catchment source waters by the slaughterhouse has been the subject of controversy. The facility owner has persistently denied breach of their licence condition and maintains it is `a very environmentally conscious operation'. The disputed nature of the possible sources of discharges and its contaminants required a detailed forensic environmental assessment. Water samples collected from off-site discharge points associated with the facility show highly elevated concentrations of faecal coliforms (max 68,000 cfu), ammonia-N (51,000 µg/L), total nitrogen (98,000 µg/L) and phosphorous (32,000 µg/L). Upstream and adjacent watercourses were markedly less contaminated. Water discharge points associated with the slaughterhouse and natural catchment runoff were sampled for arsenic speciation, including assessment for the organoarsenic compound Roxarsone. Roxarsone is used as a chicken growth promoter. Water draining the slaughterhouse facility contained concentrations around 10 times local background levels. The Roxarsone compound was not detected in any waters, but inorganic arsenic, As(V), was present in all waters with the greatest concentrations in waters draining from the slaughterhouse. The environmental evidence was compiled over a series of discharges events and presented to the NSW EPA. Subsequent to receipt of the data supported by their own investigations, the NSW EPA mandated that the slaughterhouse be subject to a pollution reduction program. The efficacy of the pollution reduction program to stem the release of highly contaminated effluent is currently subject to ongoing investigation using a suite of water chemistry measures including DNA analysis.

Removal of natural organic matter in drinking water treatment by coagulation: A comprehensive review.

PubMed

Sillanpää, Mika; Ncibi, Mohamed Chaker; Matilainen, Anu; Vepsäläinen, Mikko

2018-01-01

Natural organic matter (NOM) is a complex matrix of organic substances produced in (or channeled to) aquatic ecosystems via various biological, geological and hydrological cycles. Such variability is posing a serious challenge to most water treatment technologies, especially the ones designed to treat drinking water supplies. Lately, in addition to the fluctuating composition of NOM, a substantial increase of its concentration in fresh waters, and also municipal wastewater effluents, has been reported worldwide, which justifies the urgent need to develop highly efficient and versatile water treatment processes. Coagulation is among the most applied processes for water and wastewater treatment. The application of coagulation to remove NOM from drinking water supplies has received a great deal of attention from researchers around the world because it was efficient and helped avoiding the formation of disinfection by products (DBPs). Nonetheless, with the increased fluctuation of NOM in water (concentration and composition), the efficiency of conventional coagulation was substantially reduced, hence the need to develop enhanced coagulation processes by optimizing the operating conditions (mainly the amount coagulants and pH), developing more efficient inorganic or organic coagulants, as well as coupling coagulation with other water treatment technologies. In the present review, recent research studies dealing with the application of coagulation for NOM removal from drinking water supplies are presented and compared. In addition, integration schemes combining coagulation and other water treatment processes are presented, including membrane filtration, oxidation, adsorption and others processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application of a DNA-based luminescence switch-on method for the detection of mercury(II) ions in water samples from Hong Kong

NASA Astrophysics Data System (ADS)

He, Hong-Zhang; Leung, Ka-Ho; Fu, Wai-Chung; Shiu-Hin Chan, Daniel; Leung, Chung-Hang; Ma, Dik-Lung

2012-12-01

Mercury is a highly toxic environmental contaminant that damages the endocrine and central nervous systems. In view of the contamination of Hong Kong territorial waters with anthropogenic pollutants such as trace heavy metals, we have investigated the application of our recently developed DNA-based luminescence methodology for the rapid and sensitive detection of mercury(II) ions in real water samples. The assay was applied to water samples from Shing Mun River, Nam Sang Wai and Lamma Island sea water, representing natural river, wetland and sea water media, respectively. The results showed that the system could function effectively in real water samples under conditions of low turbidity and low metal ion concentrations. However, high turbidity and high metal ion concentrations increased the background signal and reduced the performance of this assay.

Determination of patulin in apple juice by liquid chromatography: collaborative study.

PubMed

Brause, A R; Trucksess, M W; Thomas, F S; Page, S W

1996-01-01

An AOAC International-International Union of Pure and Applied Chemistry-International Fruit Juice Union (AOAC-IUPAC-IFJU) collaborative study was conducted to evaluate a liquid chromatographic (LC) procedure for determination of patulin in apple juice. Patulin is a mold metabolite found naturally in rotting apples. Patulin is extracted with ethyl acetate, treated with sodium carbonate solution, and determined by reversed-phase LC with UV detection at 254 or 276 nm. Water, water-tetrahydrofuran, or water-acetonitrile was used as mobile phase. Levels determined in spiked test samples were 20, 50, 100, and 200 micrograms/L. A test sample naturally contaminated at 31 micrograms/L was also included. Twenty-two collaborators in 10 countries analyzed 12 test samples of apple juice. Recoveries averaged 96%, with a range of 91-108%. Repeatability relative standard deviations (RSDr) ranged from 10.9 to 53.8%. The reproducibility relative standard deviation (RSDR) ranged from 15.1 to 68.8%. The LC method for determination of patulin in apple juice has been adopted first action by AOAC INTERNATIONAL.

Determination of thiram in natural waters using flow-injection with cerium(IV)-quinine chemiluminescence system.

PubMed

Waseem, Amir; Yaqoob, Mohammad; Nabi, Abdul

2010-01-01

A simple and rapid flow-injection chemiluminescence method has been developed for the determination of dithiocarbamate fungicide thiram based on the chemiluminescence reaction of thiram with ceric sulfate and quinine in aqueous sulfuric acid. The present method allowed the determination of thiram in the concentration range of 7.5-2500 ng/mL and the detection limit (signal-to-noise ratio = 3) was 7.5 ng/mL with sample throughput of 120/h. The relative standard deviation was 2.5% for 10 replicate analyses of 500 ng/mL thiram. The effects of foreign species including various anions and cations present in water at environmentally relevant concentrations and some pesticides were also investigated. The proposed method was applied to determine thiram in spiked natural waters using octadecyl bonded phase silica (C(18)) cartridges for solid-phase extraction. The recoveries were in the range 99 +/- 1 to 104 +/- 1%. Copyright (c) 2009 John Wiley & Sons, Ltd.

DROUGHT IN THE ANTHROPOCENE: what/who causes abnormally dry conditions? (Invited)

NASA Astrophysics Data System (ADS)

Van Loon, A.; Van Lanen, H.

2013-12-01

Deforestation for agriculture, reservoir construction for hydropower, groundwater abstraction for irrigation, river diversion for navigation. These are only some examples of human interventions in river basins. The consequences of these interventions can be far-reaching, but are often difficult to distinguish from natural influences on the water system, such as meteorological droughts. River basin managers in water-stressed regions need to quantify both human and natural effects on the water system to adapt their water management accordingly. ';Drought' is a natural hazard, which is caused by climatic processes and their intrinsic variability, and cannot be prevented by short-term, local water management. ';Water scarcity' refers to the long-term unsustainable use of water resources and is a process that water managers and policy makers can influence. Water scarcity and drought are keywords for river basin managers in water-stressed regions, like Australia, California, China and the Mediterranean Basin. The interrelationship between drought and water scarcity, however, is complex. In regions with low water availability and high human pressures, water scarcity situations are common and can be exacerbated by drought events. The worst situation is a multi-year drought in a (semi )arid region with high demand for water. In monitoring the hydrological system for water management purposes, it is difficult (but essential) to determine which part of the temporal variation in a hydrological variable is caused by water scarcity (human induced) and which part by drought (natural). So the urgent question of many water managers is: how to distinguish between water scarcity and drought? Here, we present a new quantitative approach to distinguish, namely the observation-modelling framework proposed by Van Loon and Van Lanen (2013) to separate natural (drought) and human (water scarcity) effects on the hydrological system. The basis of the framework is simulation of the situation that would have occurred without human influence, i.e. the ';naturalised' situation, using a hydrological model. The resulting time series of naturalised state variables and fluxes can then be compared to observed time series. Additionally, anomalies (i.e. deviations from a threshold) are determined from both time series and compared. This analysis allows for quantification of the relative effect of drought and water scarcity. To show the general applicability of the framework, we investigated case study areas with contrasting climate and catchment properties in Spain, Czech Republic and the Netherlands. Using these case study areas we could analyse the effect of groundwater abstraction and water transfer on groundwater levels and streamflow. The proposed observation-modelling framework is rather generic. We demonstrate the range of methods that can be used and the range of human influences the framework can be applied to. The observation-modelling framework can help water managers, policy makers and stakeholders in water-stressed regions to combat water scarcity, and to better adapt to drought by decreasing their vulnerability. A clear distinction between drought and water scarcity is needed in the anthropocene.

Rapid and sensitive analytical method for monitoring of 12 organotin compounds in natural waters.

PubMed

Vahčič, Mitja; Milačič, Radmila; Sčančar, Janez

2011-03-01

A rapid analytical method for the simultaneous determination of 12 different organotin compounds (OTC): methyl-, butyl-, phenyl- and octyl-tins in natural water samples was developed. It comprises of in situ derivatisation (by using NaBEt4) of OTC in salty or fresh water sample matrix adjusted to pH 6 with Tris-citrate buffer, extraction of ethylated OTC into hexane, separation of OTC in organic phase on 15 m GC column and subsequent quantitative determination of separated OTC by ICP-MS. To optimise the pH of ethylation, phosphate, carbonate and Tris-citrate buffer were investigated alternatively to commonly applied sodium acetate - acetic acid buffer. The ethylation yields in Tris-citrate buffer were found to be better for TBT, MOcT and DOcT in comparison to commonly used acetate buffer. Iso-octane and hexane were examined as organic phase for extraction of ethylated OTC. The advantage of hexane was in its ability for quantitative determination of TMeT. GC column of 15 m in length was used for separation of studied OTC under the optimised separation conditions and its performances compared to 30 m column. The analytical method developed enables sensitive simultaneous determination of 12 different OTC and appreciably shortened analysis time in larger series of water samples. LOD's obtained for the newly developed method ranged from 0.05-0.06 ng Sn L-1 for methyl-, 0.11-0.45 ng Sn L-1 for butyl-, 0.11-0.16 ng Sn L-1 for phenyl-, and 0.07-0.10 ng Sn L-1 for octyl-tins. By applying the developed analytical method, marine water samples from the Northern Adriatic Sea containing mainly butyl- and methyl-tin species were analysed to confirm the proposed method's applicability.

Manipulation of the apoplastic pH of intact plants mimics stomatal and growth responses to water availability and microclimatic variation.

PubMed

Wilkinson, Sally; Davies, William J

2008-01-01

The apoplastic pH of intact Forsythiaxintermedia (cv. Lynwood) and tomato (Solanum lycopersicum) plants has been manipulated using buffered foliar sprays, and thereby stomatal conductance (g(s)), leaf growth rate, and plant water loss have been controlled. The more alkaline the pH of the foliar spray, the lower the g(s) and/or leaf growth rate subsequently measured. The most alkaline pH that was applied corresponds to that measured in sap extracted from shoots of tomato and Forsythia plants experiencing, respectively, soil drying or a relatively high photon flux density (PFD), vapour pressure deficit (VPD), and temperature in the leaf microclimate. The negative correlation between PFD/VPD/temperature and g(s) determined in well-watered Forsythia plants exposed to a naturally varying summer microclimate was eliminated by spraying the plants with relatively alkaline but not acidic buffers, providing evidence for a novel pH-based signalling mechanism linking the aerial microclimate with stomatal aperture. Increasing the pH of the foliar spray only reduced g(s) in plants of the abscisic acid (ABA)-deficient flacca mutant of tomato when ABA was simultaneously sprayed onto leaves or injected into stems. In well-watered Forsythia plants exposed to a naturally varying summer microclimate (variable PFD, VPD, and temperature), xylem pH and leaf ABA concentration fluctuated but were positively correlated. Manipulation of foliar apoplastic pH also affected the response of g(s) and leaf growth to ABA injected into stems of intact Forsythia plants. The techniques used here to control physiology and water use in intact growing plants could easily be applied in a horticultural context.

New Method for Electrical Conductivity Temperature Compensation

USGS Publications Warehouse

McCleskey, R. Blaine

2013-01-01

Electrical conductivity (κ) measurements of natural waters are typically referenced to 25 °C (κ25) using standard temperature compensation factors (α). For acidic waters (pH < 4), this can result in a large κ25 error (δκ25). The more the sample temperature departs from 25 °C, the larger the potential δκ25. For pH < 4, the hydrogen ion transport number becomes substantial and its mode of transport is different from most other ions resulting in a different α. A new method for determining α as a function of pH and temperature is presented. Samples with varying amounts of H2SO4 and NaCl were used to develop the new α, which was then applied to 65 natural water samples including acid mine waters, geothermal waters, seawater, and stream waters. For each sample, the κ and pH were measured at several temperatures from 5 to 90 °C and κ25 was calculated. The δκ25 ranged from −11 to 9% for the new method as compared to −42 to 25% and −53 to 27% for the constant α (0.019) and ISO-7888 methods, respectively. The new method for determining α is a substantial improvement for acidic waters and performs as well as or better than the standard methods for circumneutral waters.

The roles of bacteriophages in membrane-based water and wastewater treatment processes: A review.

PubMed

Wu, Bing; Wang, Rong; Fane, Anthony G

2017-03-01

Membrane filtration processes have been widely applied in water and wastewater treatment for many decades. Concerns related to membrane treatment effectiveness, membrane lifespan, and membrane fouling control have been paid great attention. To achieve sustainable membrane operation with regards to low energy and maintenance cost, monitoring membrane performance and applying suitable membrane control strategies are required. As the most abundant species in water and wastewater, bacteriophages have shown great potential to be employed in membrane processes as (1) indicators to assess membrane performance considering their similar properties to human pathogenic waterborne viruses; (2) surrogate particles to monitor membrane integrity due to their nano-sized nature; and (3) biological agents to alleviate membrane fouling because of their antimicrobial properties. This study aims to provide a comprehensive review on the roles of bacteriophages in membrane-based water and wastewater treatment processes, with focuses on their uses for membrane performance examination, membrane integrity monitoring, and membrane biofouling control. The advantages, limitations, and influencing factors for bacteriophage-based applications are reported. Finally, the challenges and prospects of bacteriophage-based applications in membrane processes for water treatment are highlighted. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbiological investigations on the water of a thermal bath at Budapest.

PubMed

Szuróczki, Sára; Kéki, Zsuzsa; Káli, Szandra; Lippai, Anett; Márialigeti, Károly; Tóth, Erika

2016-06-01

Thermal baths are unique aquatic environments combining a wide variety of natural and anthropogenic ecological factors, which also appear in their microbiological state. There is limited information on the microbiology of thermal baths in their complexity, tracking community shifts from the thermal wells to the pools. In the present study, the natural microbial community of well and pool waters in Gellért bath was studied in detail by cultivation-based techniques. To isolate bacteria, 10% R2A and minimal synthetic media (with "bath water") with agar-agar and gellan gum were used after prolonged incubation time; moreover, polyurethane blocks covered with media were also applied. Strains were identified by sequencing their 16S rRNA gene after grouping them by amplified rDNA restriction analysis. From each sample, the dominance of Alphaproteobacteria was characteristic though their diversity differed among samples. Members of Actinobacteria, Firmicutes, Beta- and Gamma-proteobacteria, Deinococcus-Thermus, and Bacteroidetes were also identified. Representatives of Deinococcus-Thermus phylum appeared only in the pool water. The largest groups in the pool water belonged to the Tistrella and Chelatococcus genera. The most dominant member in the well water was a new taxon, its similarity to Hartmannibacter diazotrophicus as closest relative was 93.93%.

Analysis of spatial-temporal patterns of water table change as a tool for conjunctive water management in the Upper Central Plain of the Chao Phraya River Basin, Thailand

NASA Astrophysics Data System (ADS)

Vasconcelos, Vitor Vieira; Koontanakulvong, Sucharit; Suthidhummajit, Chokchai; Junior, Paulo Pereira Martins; Hadad, Renato Moreira

2017-03-01

A sustainable strategy for conjunctive water management must include information on the temporal and spatial availability of this natural resource. Because of water shortages in the dry seasons, farmers on the Upper Plain of the Chao Phraya River basin, Thailand, are increasingly using groundwater to meet their irrigation needs. To evaluate the possibilities of conjunctive water management in the area, the spatial-temporal changes in the water table of the Younger Terrace Aquifer were investigated. First, a regional geomorphological map based on field surveys, remote sensing and previous environmental studies was developed. Then, the well data were analyzed in relation to rainfall, streamflow, yield and pumpage, and the data were interpolated using geostatistical techniques. The results were analyzed via integrated zoning based on color theory as applied to multivariate visualization. The analysis results indicate areas that would be more suitable for groundwater extraction in a conjunctive management framework with regard to the natural hydrogeological processes and the effects of human interaction. The kriging results were compared with the geomorphological map, and the geomorphological areas exhibit distinct hydrogeological patterns. The western fans exhibit the best potential for the expansion of conjunctive use, whereas the borders of the northern fans exhibit the lowest potential.

The Impact of Organo-Mineral Complexation on Mineral Weathering in the Soil Zone under Unsaturated Conditions

NASA Astrophysics Data System (ADS)

Michael, H. A.; Tan, F.; Yoo, K.; Imhoff, P. T.

2017-12-01

While organo-mineral complexes can protect organic matter (OM) from biodegradation, their impact on soil mineral weathering is not clear. Previous bench-scale experiments that focused on specific OM and minerals showed that the adsorption of OM to mineral surfaces accelerates the dissolution of some minerals. However, the impact of natural organo-mineral complexes on mineral dissolution under unsaturated conditions is not well known. In this study, soil samples prepared from an undisturbed forest site were used to determine mineral weathering rates under differing conditions of OM sorption to minerals. Two types of soil samples were generated: 1) soil with OM (C horizon soil from 84-100cm depth), and 2) soil without OM (the same soil as in 1) but with OM removed by heating to 350°for 24 h). Soil samples were column-packed and subjected to intermittent infiltration and drainage to mimic natural rainfall events. Each soil sample type was run in duplicate. The unsaturated condition was created by applying gas pressure to the column, and the unsaturated chemical weathering rates during each cycle were calculated from the effluent concentrations. During a single cycle, when applying the same gas pressure, soils with OM retained more moisture than OM-removed media, indicating increased water retention capacity under the impact of OM. This is consistent with the water retention data measured by evaporation experiments (HYPROP) and the dew point method (WP4C Potential Meter). Correspondingly, silicon (Si) denudation rates indicated that dissolution of silicate minerals was 2-4 times higher in OM soils, suggesting that organo-mineral complexes accelerate mineral dissolution under unsaturated conditions. When combining data from all cycles, the results showed that Si denudation rates were positively related to soil water content: denundation rate increased with increasing water content. Therefore, natural mineral chemical weathering under unsaturated conditions, while widely considered to be facilitated by biological and chemical activities, may also be affected by soil retention properties.

Advanced oxidation process-mediated removal of pharmaceuticals from water: A review.

PubMed

Kanakaraju, Devagi; Glass, Beverley D; Oelgemöller, Michael

2018-08-01

Pharmaceuticals, which are frequently detected in natural and wastewater bodies as well as drinking water have attracted considerable attention, because they do not readily biodegrade and may persist and remain toxic. As a result, pharmaceutical residues pose on-going and potential health and environmental risks. To tackle these emerging contaminants, advanced oxidation processes (AOPs) such as photo-Fenton, sonolysis, electrochemical oxidation, radiation and ozonation etc. have been applied to remove pharmaceuticals. These processes utilize the high reactivity of hydroxyl radicals to progressively oxidize organic compounds to innocuous products. This review provides an overview of the findings from recent studies, which have applied AOPs to degrade pharmaceutical compounds. Included is a discussion that links various factors of TiO 2 -mediated photocatalytic treatment to its effectiveness in degrading pharmaceutical residues. This review furthermore highlights the success of AOPs in the removal of pharmaceuticals from different water matrices and recommendations for future studies are outlined. Copyright © 2018 Elsevier Ltd. All rights reserved.

Marine Radioactivity Studies in the Suez Canal, Part II: Field Experiments and a Modelling Study of Dispersion

NASA Astrophysics Data System (ADS)

Abril, J. M.; Abdel-Aal, M. M.; Al-Gamal, S. A.; Abdel-Hay, F. A.; Zahar, H. M.

2000-04-01

In this paper we take advantage of the two field tracing experiments carried out under the IAEA project EGY/07/002, to develop a modelling study on the dispersion of radioactive pollution in the Suez Canal. The experiments were accomplished by using rhodamine B as a tracer, and water samples were measured by luminescence spectrometry. The presence of natural luminescent particles in the canal waters limited the use of some field data. During experiments, water levels, velocities, wind and other physical parameters were recorded to supply appropriate information for the modelling work. From this data set, the hydrodynamics of the studied area has been reasonably described. We apply a 1-D-Gaussian and 2-D modelling approaches to predict the position and the spatial shape of the plume. The use of different formulations for dispersion coefficients is studied. These dispersion coefficients are then applied in a 2-D-hydrodynamic and dispersion model for the Bitter Lake to investigate different scenarios of accidental discharges.

Limitations of fluorescence spectroscopy to characterize organic matter in engineered systems

NASA Astrophysics Data System (ADS)

Korak, J.

2017-12-01

Fluorescence spectroscopy has been widely used to characterize dissolved organic matter (DOM) in engineered systems, such as drinking water, municipal wastewater and industrial water treatment. While fluorescence data collected in water treatment applications has led to the development of strong empirical relationships between fluorescence responses and process performance, the use of fluorescence to infer changes in the underlying organic matter chemistry is often oversimplified and applied out of context. Fluorescence only measures a small fraction of DOM as fluorescence quantum yields are less than 5% for many DOM sources. Relying on fluorescence as a surrogate for DOM presence, character or reactivity may not be appropriate for systems where small molecular weight, hydrophilic constituents unlikely to fluoresce are important. In addition, some methods rely on interpreting fluorescence signals at different excitation wavelengths as a surrogate for operationally-defined humic- and fulvic-acids in lieu of traditional XAD fractionation techniques, but these approaches cannot be supported by other lines of evidence considering natural abundance and fluorescence quantum yields of these fractions. These approaches also conflict with parallel factor analysis (PARAFAC), a statistical approach that routinely identifies fluorescence components with dual excitation behavior. Lastly, methods developed for natural systems are often applied out of context to engineered systems. Fluorescence signals characteristic of phenols or indoles are often interpreted as indicators for biological activity in natural systems due to fluorescent amino acids and peptides, but this interpretation is may not be appropriate in engineering applications where non-biological sources of phenolic functional groups may be present. This presentation explores common fluorescence interpretation approaches, discusses the limitations and provides recommendations related to engineered systems.

Regulation of water, salinity, and cold stress responses by salicylic acid

PubMed Central

Miura, Kenji; Tada, Yasuomi

2014-01-01

Salicylic acid (SA) is a naturally occurring phenolic compound. SA plays an important role in the regulation of plant growth, development, ripening, and defense responses. The role of SA in the plant–pathogen relationship has been extensively investigated. In addition to defense responses, SA plays an important role in the response to abiotic stresses, including drought, low temperature, and salinity stresses. It has been suggested that SA has great agronomic potential to improve the stress tolerance of agriculturally important crops. However, the utility of SA is dependent on the concentration of the applied SA, the mode of application, and the state of the plants (e.g., developmental stage and acclimation). Generally, low concentrations of applied SA alleviate the sensitivity to abiotic stresses, and high concentrations of applied induce high levels of oxidative stress, leading to a decreased tolerance to abiotic stresses. In this article, the effects of SA on the water stress responses and regulation of stomatal closure are reviewed. PMID:24478784

Fluometuron and pendimethalin runoff from strip and conventionally tilled cotton in the southern atlantic coastal plain.

PubMed

Potter, Thomas L; Truman, Clint C; Bosch, David D; Bednarz, Craig

2004-01-01

In the Atlantic Coastal Plain region of southern Georgia (USA), cotton (Gossypium hirsutum L.) acreage increased threefold in the past decade. To more effectively protect water quality in the region, best management practices are needed that reduce pesticide runoff from fields in cotton production. This study compared runoff of two herbicides, fluometuron [N,N-dimethyl-N'-[3-(trifluoromethyl)-phenyl]-urea] and pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitro-benzenamine], from plots in strip-tillage (ST) and conventional-tillage (CT) management near Tifton, GA. Rainfall simulations were conducted one day after preemergence herbicide applications to 0.0006-ha plots and runoff from 0.15-ha plots due to natural rainfall following preemergence pendimethalin and fluometuron and postemergence fluometuron use was monitored. Pendimethalin runoff was greater under CT than ST due to strong pendimethalin soil sorption and higher erosion and runoff under CT. The highest losses, 1.3% of applied in CT and 0.22% of applied in ST, were observed during rainfall simulations conducted 1 DAT. Fluometuron runoff from natural rainfall was substantially lower from ST than from CT plots but the trend was reversed in rainfall simulations. In all studies, fluometuron runoff was also relatively low (<1% of applied), and on plots under natural rainfall, desmethylfluometuron (DMF) represented about 50% of total fluometuron runoff. Fluometuron's relatively low runoff rate appeared linked to its rapid leaching, and high DMF detection rates in runoff support DMF inclusion in fluometuron risk assessments. Results showed that ST has the potential to reduce runoff of both herbicides, but fluometuron leaching may be a ground water quality concern.

A triangular fuzzy TOPSIS-based approach for the application of water technologies in different emergency water supply scenarios.

PubMed

Qu, Jianhua; Meng, Xianlin; Yu, Huan; You, Hong

2016-09-01

Because of the increasing frequency and intensity of unexpected natural disasters, providing safe drinking water for the affected population following a disaster has become a global challenge of growing concern. An onsite water supply technology that is portable, mobile, or modular is a more suitable and sustainable solution for the victims than transporting bottled water. In recent years, various water techniques, such as membrane-assisted technologies, have been proposed and successfully implemented in many places. Given the diversity of techniques available, the current challenge is how to scientifically identify the optimum options for different disaster scenarios. Hence, a fuzzy triangular-based multi-criteria, group decision-making tool was developed in this research. The approach was then applied to the selection of the most appropriate water technologies corresponding to the different emergency water supply scenarios. The results show this tool capable of facilitating scientific analysis in the evaluation and selection of emergency water technologies for enduring security drinking water supply in disaster relief.

Influence of root-water-uptake parameterization on simulated heat transport in a structured forest soil

NASA Astrophysics Data System (ADS)

Votrubova, Jana; Vogel, Tomas; Dohnal, Michal; Dusek, Jaromir

2015-04-01

Coupled simulations of soil water flow and associated transport of substances have become a useful and increasingly popular tool of subsurface hydrology. Quality of such simulations is directly affected by correctness of its hydraulic part. When near-surface processes under vegetation cover are of interest, appropriate representation of the root water uptake becomes essential. Simulation study of coupled water and heat transport in soil profile under natural conditions was conducted. One-dimensional dual-continuum model (S1D code) with semi-separate flow domains representing the soil matrix and the network of preferential pathways was used. A simple root water uptake model based on water-potential-gradient (WPG) formulation was applied. As demonstrated before [1], the WPG formulation - capable of simulating both the compensatory root water uptake (in situations when reduced uptake from dry layers is compensated by increased uptake from wetter layers), and the root-mediated hydraulic redistribution of soil water - enables simulation of more natural soil moisture distribution throughout the root zone. The potential effect on heat transport in a soil profile is the subject of the present study. [1] Vogel T., M. Dohnal, J. Dusek, J. Votrubova, and M. Tesar. 2013. Macroscopic modeling of plant water uptake in a forest stand involving root-mediated soil-water redistribution. Vadose Zone Journal, 12, 10.2136/vzj2012.0154. The research was supported by the Czech Science Foundation Project No. 14-15201J.

Effects of land use and land cover changes on water quality in the uMngeni river catchment, South Africa

NASA Astrophysics Data System (ADS)

Namugize, Jean Nepomuscene; Jewitt, Graham; Graham, Mark

2018-06-01

Land use and land cover change are major drivers of water quality deterioration in watercourses and impoundments. However, understanding of the spatial and temporal variability of land use change characteristics and their link to water quality parameters in catchments is limited. As a contribution to address this limitation, the objective of this study is to assess the linkages between biophysico-chemical water quality parameters and land use and land cover (LULC) classes in the upper reaches of the uMngeni Catchment, a rapidly developing catchment in South Africa. These were assessed using Geographic Information Systems tools and statistical analyses for the years 1994, 2000, 2008 and 2011 based on changes over time of eight LULC classes and available water quality information. Natural vegetation, forest plantations and cultivated areas occupy 85% of the catchment. Cultivated, urban/built-up and degraded areas increased by 6%, 4.5% and 3%, respectively coinciding with a decrease in natural vegetation by 17%. Variability in the concentration of water quality parameters from 1994 to 2011 and an overall decline in water quality were observed. Escherichia coli (E. coli) levels exceeding the recommended guidelines for recreation and public health protection was noted as a major issue at seven of the nine sampling points. Overall, water supply reservoirs in the catchment retained over 20% of nutrients and over 85% of E. coli entering them. A relationship between land use types and water quality variables was found. However, the degree and magnitude of the associations varies between sub-catchments and is difficult to quantify. This highlights the complexity and the site-specific nature of relationships between land use types and water quality parameters in the catchment. Thus, this study provides useful findings on the general relationship between land use and land cover and water quality degradation, but highlights the risks of applying simple relationships or adding complex relationships in the management of the catchment.

Water Resources and Sustainable Agriculture in 21st Century: Challenges and Opportunities

NASA Astrophysics Data System (ADS)

Asrar, G.

2008-05-01

Global agriculture faces some unique challenges and opportunities for the rest of this century. The need for food, feed and fiber will continues to grow as the world population continue to increase in the future. Agricultural ecosystems are also expected to be the source of a significant portion of renewable energy and fuels around the world, without further compromising the integrity of the natural resources base. How can agriculture continue to provide these services to meet the growing needs of world population while sustaining the integrity of agricultural ecosystems and natural resources, the very foundation it depends on? In the last century, scientific discoveries and technological innovations in agriculture resulted in significant increase in food, feed and fiber production globally, while the total amount of water, energy, fertilizers and other input used to achieve this growth remained the same or even decreased significantly in some parts of the world. Scientific and technical advances in understanding global and regional water and energy cycles, water resources management, soil and water conservation practices, weather prediction, plant breeding and biotechnology, and information and communication technologies contributed to this tremendous achievement. The projected increase in global population, urbanization, and changing lifestyles will continue the pressure on both agriculture and other managed and natural ecosystems to provide necessary goods and services for the rest of this century. To meet these challenges, we must obtain the requisite scientific and technical advances in the functioning of Earth's water, energy, carbon and biogeochemical cycles. We also need to apply the knowledge we gain and technologies we develop in assessing Earth's ecosystems' conditions, and their management and stewardship. In agricultural ecosystems, management of soil and water quality and quantity together with development of new varieties of plants based on advances in genomic, genetics, breeding and applied biotechnologies are a key to our ability to address these challenges. We must also continue to develop agronomic practices that sustain the integrity of natural resources and conserve energy on one-hand while maximizing agricultural production per unit area of land on the other hand. This will require managing agricultural ecosystems for their multiple functions and services together, instead of looking at each function/service in isolation. In this presentation, we will provide an overview of the scientific and technical knowledge required for sustainable management of agricultural ecosystems and associated natural resources. We will describe the soil, water and energy research needs/priorities in agriculture. We will also provide some examples of recent accomplishments and future directions in developing decision support tools for assessing the impacts of weather and climate variations and change, and their risk to agricultural ecosystems. We will then focus on opportunities and challenges associated with measurement, monitoring and modeling of soil moisture and its use in management and operation of agricultural ecosystems. The overall intent of this presentation is to stimulate some discussion on future directions and priorities for soil, water and energy research in agricultural ecosystems, and how the knowledge we gain from this research can be conveyed to the users for risk assessment, decision making, and multi-service ecosystem management purposes.

Retrieving water productivity parameters by using Landsat images in the Nilo Coelho irrigation scheme, Brazil

NASA Astrophysics Data System (ADS)

de C. Teixeira, Antônio H.; Lopes, Hélio L.; Hernandez, Fernando B. T.; Scherer-Warren, Morris; Andrade, Ricardo G.; Neale, Christopher M. U.

2013-10-01

The Nilo Coelho irrigation scheme, located in the semi-arid region of Brazil, is highlighted as an important agricultural irrigated perimeter. Considering the scenario of this fast land use change, the development and application of suitable tools to quantify the trends of the water productivity parameters on a large scale is important. To analyse the effects of land use change within this perimeter, the large-scale values of biomass production (BIO) and actual evapotranspiration (ET) were quantified from 1992 to 2011, under the naturally driest conditions along the year. Monteith's radiation model was applied for estimating the absorbed photosynthetically active radiation (APAR), while the SAFER (Simple Algorithm For Evapotranspiration Retrieving) algorithm was used to retrieve ET. The highest incremental BIO values happened during the years of 1999 and 2005, as a result of the increased agricultural area under production inside the perimeter, when the average differences between irrigated crops and natural vegetation were more than 70 kg ha-1 d-1. Comparing the average ET rates of 1992 (1.6 mm d-1) with those for 2011 (3.1 mm d-1), it was verified that the extra water consumption doubled because of the increments of irrigated areas along the years. More uniformity along the years on both water productivity parameters occurred for natural vegetation, evidenced by the lower values of standard deviation when comparing to irrigated crops. The heterogeneity of ET values under irrigation conditions are due to the different species, crop stages, cultural and water managements.

18 CFR Appendix II to Subpart F of... - Procedures for Compliance With the National Historic Preservation Act of 1966 Under § 157.206(b...

Code of Federal Regulations, 2012 CFR

2012-04-01

... Subpart F of Part 157 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR CERTIFICATES OF PUBLIC CONVENIENCE...)(ii) The following procedures apply to any certificate holder which undertakes a project under the...

18 CFR Appendix II to Subpart F of... - Procedures for Compliance With the National Historic Preservation Act of 1966 Under § 157.206(b...

Code of Federal Regulations, 2013 CFR

2013-04-01

... Subpart F of Part 157 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR CERTIFICATES OF PUBLIC CONVENIENCE...)(ii) The following procedures apply to any certificate holder which undertakes a project under the...

18 CFR Appendix II to Subpart F of... - Procedures for Compliance With the National Historic Preservation Act of 1966 Under § 157.206(b...

Code of Federal Regulations, 2010 CFR

2010-04-01

... Subpart F of Part 157 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR CERTIFICATES OF PUBLIC CONVENIENCE...)(ii) The following procedures apply to any certificate holder which undertakes a project under the...

18 CFR Appendix II to Subpart F of... - Procedures for Compliance With the National Historic Preservation Act of 1966 Under § 157.206(b...

Code of Federal Regulations, 2014 CFR

2014-04-01

... Subpart F of Part 157 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR CERTIFICATES OF PUBLIC CONVENIENCE...)(ii) The following procedures apply to any certificate holder which undertakes a project under the...

18 CFR Appendix II to Subpart F of... - Procedures for Compliance With the National Historic Preservation Act of 1966 Under § 157.206(b...

Code of Federal Regulations, 2011 CFR

2011-04-01

... Subpart F of Part 157 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER NATURAL GAS ACT APPLICATIONS FOR CERTIFICATES OF PUBLIC CONVENIENCE...)(ii) The following procedures apply to any certificate holder which undertakes a project under the...

Specific extraction of chromium as tetrabutylammonium-chromate and spectrophotometric determination by diphenylcarbazide: speciation of chromium in effluent streams.

PubMed

Noroozifar, M; Khorasani-Motlagh, M

2003-05-01

A very specific, selective, simple, and inexpensive procedure was developed for the speciation of CrVI and CrIII. This method is based on the quantitative extraction of chromate and CrIII (previously oxidized to CrVI) as a tetrabutylammonium-chromate ion-pair in methyl isobutyl ketone (MIBK), and then back extraction and preconcentration with an acidic diphenylcarbazide (DPC) solution. Back extraction was applied to achieve further preconcentration by a final factor of 20. The CrVI-DPC complex was determined in back-extract by a spectrophotometer at 548 nm. Under these extraction conditions, most of the probable concomitant cations and anions remained in the first inorganic phase. The calibration curve was linear up to 0.14 microg L(-1) of CrVI with a detection limit of 2.22 ng L(-1). The developed procedure was found to be suitable for the determination of the CrVI and CrIII species in various natural water samples with a relative standard deviation of better than 1.6%. The method was successfully applied to the speciation of chromium in spiked natural water samples, and also samples of effluent from a leather treatment plant.

Constraints from Naturally Deformed Peridotites on Controls on Olivine Lattice Preferred Orientation

NASA Astrophysics Data System (ADS)

Bernard, R. E.; Behr, W. M.

2016-12-01

Seismic anisotropy in the upper mantle is produced primarily by lattice preferred orientations (LPO) in olivine formed during viscous deformation. Because seismic anisotropy is one of the principal means of characterizing upper mantle flow directions, it is critical to understand how LPO is affected by deformation conditions. Laboratory experiments suggest that water content and stress magnitude each play key roles in the development of LPO in olivine under experimental conditions, but it is unclear to what extent these results apply to natural conditions. We use peridotite xenoliths from a wide range of tectonic settings (Lunar Craters, Geronimo, and San Carlos volcanic fields in the Basin and Range; Cima and Deadman Lake volcanic fields in the Mojave; the Navajo Volcanic field in the Colorado Plateau; and the Potrillo volcanic field in the Rio Grande Rift region) to investigate correlations between water content, stress, and olivine LPO in natural rocks. Water contents were measured using Secondary Ion Mass Spectrometry, stress magnitudes using paleopiezometry, and LPOs using electron backscatter diffraction. The samples examined exhibit a range of fabric types, including A-, B-, C-, and E-type LPOs. Mojave xenoliths show no difference in water content between A- and E-type LPO; instead, differences in fabric type appear to reflect variations in strain magnitude. Samples from the Navajo volcanic field do show a correlation between water influx and stress magnitude as they exhibit abundant hydrous minerals and high water contents, stress magnitudes greater than 250 MPa and B-type olivine LPOs. Additional results from other xenolith suites will be presented at the meeting.

Accurate experimental determination of the isotope effects on the triple point temperature of water. II. Combined dependence on the 18O and 17O abundances

NASA Astrophysics Data System (ADS)

Faghihi, V.; Kozicki, M.; Aerts-Bijma, A. T.; Jansen, H. G.; Spriensma, J. J.; Peruzzi, A.; Meijer, H. A. J.

2015-12-01

This paper is the second of two articles on the quantification of isotope effects on the triple point temperature of water. In this second article, we address the combined effects of 18O and 17O isotopes. We manufactured five triple point cells with waters with 18O and 17O abundances exceeding widely the natural abundance range while maintaining their natural 18O/17O relationship. The 2H isotopic abundance was kept close to that of VSMOW (Vienna Standard Mean Ocean Water). These cells realized triple point temperatures ranging between  -220 μK to 1420 μK with respect to the temperature realized by a triple point cell filled with VSMOW. Our experiment allowed us to determine an accurate and reliable value for the newly defined combined 18, 17O correction parameter of AO  =  630 μK with a combined uncertainty of 10 μK. To apply this correction, only the 18O abundance of the TPW needs to be known (and the water needs to be of natural origin). Using the results of our two articles, we recommend a correction equation along with the coefficient values for isotopic compositions differing from that of VSMOW and compare the effect of this new equation on a number of triple point cells from the literature and from our own institute. Using our correction equation, the uncertainty in the isotope correction for triple point cell waters used around the world will be  <1 μK.

Applied socio-hydrology using volunteer geographic information (VGI) to integrate ecosystem-based adaptation (EbA) and disaster risk reduction (DRR)

NASA Astrophysics Data System (ADS)

Mendiondo, Eduardo; Taffarello, Denise; Mohor, Guilherme; Guzmán, Diego; Câmara de Freitas, Clarissa; Fava, Maria Clara; Restrepo, Camilo; Abreu, Fernando; Batalini, Marina; Lago, Cesar; Abe, Narumi; Rosa, Altair

2017-04-01

Socio-hydrology proposes to understand coupled human-water systems by conceptualizing its components to be dynamically connected by bi-directional feedbacks. For practical purposes, especially in developing countries of South America, socio-hydrology does integrate practical, empirical and theoretical fundamentals from citizens' knowledge and culture. This contribution shows South American examples of how volunteer geographic information (VGI) can help socio-hydrology to integrate emerging aspects with heavy feedbacks, exploding uncertainties and relevant scales of socio-hydrological scales. Here we select examples at different scales of using VGI to link aspects of ecosystem-based adaptation (EbA) and disaster risk reduction (DRR). On the one hand, we show some learning cases of EbA/VGI linked to socio-hydrology also related with water valuation, both monetary and non-monetary, under scenarios of changing conditions of land-use and land cover changes of strategic water supply systems in subtropical biomes. This example brings a bridge of VGI and EbA towards Disaster Risk Reduction (DRR) through water topics of securitization, insurance, smart cities and sustainable urban drainage systems (SUDS). Thus, on the other hand, we also depict how VGI support applied elements for socio-hydrology on South American urban areas, capable of policy actions for DRR through SUDS at human-impacted biomes under extremes of droughts, floods and pollution. We here recommend yardsticks of learning conditions from these real examples of using VGI's knowledge and culture biases for a more resilient socio-hydrology, in order to create opportunities for theoretical, conceptual and applied nature of EbA and DRR with viable alliances from IAHS/Panta Rhei with UN/Sendai/DRR Framework and UN/Sustainable Development Goals. From these examples, however, seem plausible co-evolutionary dynamics with stakeholders if local-scale constraints, from sociopolitical nature, institutions' policies and approaches, were robustly addressed.

Estimates of natural streamflow at two streamgages on the Esopus Creek, New York, water years 1932 to 2012

USGS Publications Warehouse

Burns, Douglas A.; Gazoorian, Christopher L.

2015-01-01

Natural discharge at the Mount Marion streamgage was estimated by summing the natural discharge estimated for the Coldbrook streamgage and the discharge estimated for the intervening basin area through application of the New York Streamflow Estimation Tool, recently developed for estimating unaltered streamflow at ungaged locations in the State. Estimates of natural daily discharge at the Mount Marion streamgage were about three times greater than gaged daily discharge throughout the moderate- to low-flow range from October 1, 1970, to September 30, 2012, the period of record for full water years at this streamgage. The relative difference between the two discharge time series declined as flow increased beyond the moderate range, but gaged daily discharge was still 25 to 43 percent less than estimated natural daily discharge for the high-flow metrics calculated in this analysis, and the mean relative difference was 43 percent for the annual 1-day maximum discharge. Overall, these estimates of natural discharge reflect the absence of effects of the Shandaken Tunnel and Ashokan Reservoir on flows in the Esopus Creek over broad time frames. However, caution is warranted if one is attempting to apply the natural estimates at short time scales because the regression prediction intervals indicate that uncertainty at a daily time step ranges from about 40 to 80 percent.

Sustainable management of river oases along the Tarim River in North-Western China under conditions of climate change

NASA Astrophysics Data System (ADS)

Rumbaur, C.; Thevs, N.; Disse, M.; Ahlheim, M.; Brieden, A.; Cyffka, B.; Doluschitz, R.; Duethmann, D.; Feike, T.; Frör, O.; Gärtner, P.; Halik, Ü.; Hill, J.; Hinnenthal, M.; Keilholz, P.; Kleinschmit, B.; Krysanova, V.; Kuba, M.; Mader, S.; Menz, C.; Othmanli, H.; Pelz, S.; Schroeder, M.; Siew, T. F.; Stender, V.; Stahr, K.; Thomas, F. M.; Welp, M.; Wortmann, M.; Zhao, X.; Chen, X.; Jiang, T.; Zhao, C.; Zhang, X.; Luo, J.; Yimit, H.; Yu, R.

2014-10-01

The Tarim River Basin, located in Xinjiang, NW China, is the largest endorheic river basin of China and one of the largest in whole Central Asia. Due to the extremely arid climate with an annual precipitation of less than 100 mm, the water supply along the Aksu and Tarim River solely depends on river water. This applies for anthropogenic activities (e.g. agriculture) as well as for the natural ecosystems so that both compete for water. The on-going increase of water consumption by agriculture and other human activities in this region has been enhancing the competition for water between human needs and nature. Against this background, 11 German and 6 Chinese universities and research institutes formed the consortium SuMaRiO (www.sumario.de), which aims at gaining a holistic picture of the availability of water resources in the Tarim River Basin and the impacts on anthropogenic activities and natural ecosystems caused by the water distribution within the Tarim River Basin. The discharge of the Aksu River, which is the major tributary to the Tarim, has been increasing over the past 6 decades due to enhanced glacier melt. Alone from 1989 to 2011, the area under agriculture more than doubled. Thereby, cotton became the major crop and there was a shift from small-scale farming to large-scale intensive farming. The major natural ecosystems along the Aksu and Tarim River are riparian ecosystems: Riparian (Tugai) forests, shrub vegetation, reed beds, and other grassland. Within the SuMaRiO Cluster the focus was laid on the Tugai forests, with Populus euphratica as dominant tree, because the most productive and species-rich natural ecosystems can be found among those forests. On sites with groundwater distance of less than 7.5 m the annual increments correlated with river runoffs of the previous year. But, the further downstream along the Tarim River, the more the natural river dynamics ceased, which impacts on the recruitment of Populus euphratica. Household surveys revealed that there is a considerable willingness to pay for conservation of those riparian forests with the mitigation of dust and sandstorms considered as the most important ecosystem service. This interdisciplinary project will result in a decision support tool (DST), build on the participation of regional stakeholders and models based on results and field experiments. This DST finally shall assist stakeholders in balancing the water competition acknowledging the major external effects of any water allocation.

Application of the conjugate-gradient method to ground-water models

USGS Publications Warehouse

Manteuffel, T.A.; Grove, D.B.; Konikow, Leonard F.

1984-01-01

The conjugate-gradient method can solve efficiently and accurately finite-difference approximations to the ground-water flow equation. An aquifer-simulation model using the conjugate-gradient method was applied to a problem of ground-water flow in an alluvial aquifer at the Rocky Mountain Arsenal, Denver, Colorado. For this application, the accuracy and efficiency of the conjugate-gradient method compared favorably with other available methods for steady-state flow. However, its efficiency relative to other available methods depends on the nature of the specific problem. The main advantage of the conjugate-gradient method is that it does not require the use of iteration parameters, thereby eliminating this partly subjective procedure. (USGS)

Effects of using a posteriori methods for the conservation of integral invariants. [for weather forecasting

NASA Technical Reports Server (NTRS)

Takacs, Lawrence L.

1988-01-01

The nature and effect of using a posteriori adjustments to nonconservative finite-difference schemes to enforce integral invariants of the corresponding analytic system are examined. The method of a posteriori integral constraint restoration is analyzed for the case of linear advection, and the harmonic response associated with the a posteriori adjustments is examined in detail. The conservative properties of the shallow water system are reviewed, and the constraint restoration algorithm applied to the shallow water equations are described. A comparison is made between forecasts obtained using implicit and a posteriori methods for the conservation of mass, energy, and potential enstrophy in the complete nonlinear shallow-water system.

Natural and anthropogenic decadal pH decrease in the North Atlantic and Mediterranean Sea waters

NASA Astrophysics Data System (ADS)

Huertas, E.; Flecha, S.; Murata, A.; Garcia Lafuente, J.; Pérez, F. F.

2017-12-01

Seawater pH is undergoing a decreasing trend due to atmospheric CO2 absorption, a phenomenon known as Ocean Acidification (OA) that has been documented in different ocean regions. Certain marine basins are more vulnerable to OA, such as the Mediterranean Sea (MS), which is attributed to particular water circulation processes and biogeochemical features. Considering previous studies on OA in Mediterranean and Atlantic water masses, the main aim of this work was to identify for the first time the natural and anthropogenic contribution to decadal pH variations. Therefore, an archetypal analysis was applied to pH measurements and other biogeochemical variables collected in the Strait of Gibraltar during 10 years. Our results reveal that the biological component of the pH change in the Western Mediterranean Deep Water (WMDW) (ΔpHWMDW) represents around 56% of the total decadal pH decrease observed, highlighting the relevance of the remineralization occurring in the Alboran basin, where the WMDW resides before leaving the MS. On the other hand, neither natural nor anthropogenic forcing on the pH change in the Levantine Intermediate Water (ΔpHLIW) was detected, as pH variation was negligible. As for the North Atlantic Central Water (NACW), atmospheric CO2 uptake was responsible of 58% of the ΔpHNACW, likely related to permanent contact with the atmosphere. Additionally, estimations of the approximated ages of the NACW, LIW and WMDW in the SG of about 8, 34 and 32 years respectively have been obtained. Our results show that Mediterranean waters undergo changes in their biogeochemical characteristics during transit through the SG and gives insights on the main mechanisms affecting pH variations occurring from their formation sites to the SG.

Rainwater propagation through snowpack during rain-on-snow sprinkling experiments under different snow conditions

NASA Astrophysics Data System (ADS)

Juras, Roman; Würzer, Sebastian; Pavlásek, Jirka; Vitvar, Tomáš; Jonas, Tobias

2017-09-01

The mechanisms of rainwater propagation and runoff generation during rain-on-snow (ROS) events are still insufficiently known. Understanding storage and transport of liquid water in natural snowpacks is crucial, especially for forecasting of natural hazards such as floods and wet snow avalanches. In this study, propagation of rainwater through snow was investigated by sprinkling experiments with deuterium-enriched water and applying an alternative hydrograph separation technique on samples collected from the snowpack runoff. This allowed us to quantify the contribution of rainwater, snowmelt and initial liquid water released from the snowpack. Four field experiments were carried out during winter 2015 in the vicinity of Davos, Switzerland. Blocks of natural snow were isolated from the surrounding snowpack to inhibit lateral exchange of water and were exposed to artificial rainfall using deuterium-enriched water. The experiments were composed of four 30 min periods of sprinkling, separated by three 30 min breaks. The snowpack runoff was continuously gauged and sampled periodically for the deuterium signature. At the onset of each experiment antecedent liquid water was first pushed out by the sprinkling water. Hydrographs showed four pronounced peaks corresponding to the four sprinkling bursts. The contribution of rainwater to snowpack runoff consistently increased over the course of the experiment but never exceeded 86 %. An experiment conducted on a non-ripe snowpack suggested the development of preferential flow paths that allowed rainwater to efficiently propagate through the snowpack limiting the time for mass exchange processes to take effect. In contrast, experiments conducted on ripe isothermal snowpack showed a slower response behaviour and resulted in a total runoff volume which consisted of less than 50 % of the rain input.

Water resources planning for rivers draining into mobile bay

NASA Technical Reports Server (NTRS)

Ng, S.; April, G. C.

1976-01-01

A hydrodynamic model describing water movement and tidal elevation is formulated, computed, and used to provide basic data about water quality in natural systems. The hydrodynamic model is based on two-dimensional, unsteady flow equations. The water mass is considered to be reasonably mixed such that integration (averaging) in the depth direction is a valid restriction. Convective acceleration, the Coriolis force, wind and bottom interactions are included as contributing terms in the momentum equations. The solution of the equations is applied to Mobile Bay, and used to investigate the influence that river discharge rate, wind direction and speed, and tidal condition have on water circulation and holdup within the bay. Storm surge conditions, oil spill transport, artificial island construction, dredging, and areas subject to flooding are other topics which could be investigated using the mathematical modeling approach.

Fracking, fracture, and permeability

NASA Astrophysics Data System (ADS)

Turcotte, D. L.; Norris, J.; Rundle, J. B.

2013-12-01

Injections of large volumes of water into tight shale reservoirs allows the extraction of oil and gas not previously accessible. This large volume 'super' fracking induces damage that allows the oil and/or gas to flow to an extraction well. The purpose of this paper is to provide a model for understanding super fracking. We assume that water is injected from a small spherical cavity into a homogeneous elastic medium. The high pressure of the injected water generates hoop stresses that reactivate natural fractures in the tight shales. These fractures migrate outward as water is added creating a spherical shell of damaged rock. The porosity associated with these fractures is equal to the water volume injected. We obtain an analytic expression for this volume. We apply our model to a typical tight shale reservoir and show that the predicted water volumes are in good agreement with the volumes used in super fracking.

Advancement in Electrospun Nanofibrous Membranes Modification and Their Application in Water Treatment

PubMed Central

Nasreen, Shaik Anwar Ahamed Nabeela; Sundarrajan, Subramanian; Nizar, Syed Abdulrahim Syed; Balamurugan, Ramalingam; Ramakrishna, Seeram

2013-01-01

Water, among the most valuable natural resources available on earth, is under serious threat as a result of undesirable human activities: for example, marine dumping, atmospheric deposition, domestic, industrial and agricultural practices. Optimizing current methodologies and developing new and effective techniques to remove contaminants from water is the current focus of interest, in order to renew the available water resources. Materials like nanoparticles, polymers, and simple organic compounds, inorganic clay materials in the form of thin film, membrane or powder have been employed for water treatment. Among these materials, membrane technology plays a vital role in removal of contaminants due to its easy handling and high efficiency. Though many materials are under investigation, nanofibers driven membrane are more valuable and reliable. Synthetic methodologies applied over the modification of membrane and its applications in water treatment have been reviewed in this article. PMID:24957057

The use of Moringa Oleifera Seed Powder as Coagulant to Improve the Quality of Wastewater and Ground Water

NASA Astrophysics Data System (ADS)

Hendrawati; Rani Yuliastri, Indra; Nurhasni; Rohaeti, Eti; Effendi, Hefni; Darusman, Latifah K.

2016-01-01

Wastewater and ground water treatment are mostly using Polyaluminum Chloride (PAC), a synthetic coagulant, which possess health risk and require expensive cost. This research was carried out to observe the effect of Moringa oleifera seed as natural coagulant to replace synthetic coagulant. M. oleifera reduced 98.6% turbidity of wastewater, 10.8% of its conductivity, 11.7% of its BOD and removed its metal contents (Cd, Cr, Mn). When applied to ground water, M. oleifera removed the turbidity of ground water as much as 97.5%, while reduced the conductivity and BOD of ground water 53.4% and 18%, respectively. The use of M. oleifera also reduced total number of coliform. The advantage of using M. oleifera is that it does not reduce pH as PAC, hence does not require further treatment to adjust pH of the treated water.

RNA-Seq Transcriptome Profiling of Upland Cotton (Gossypium hirsutum L.) Root Tissue under Water-Deficit Stress

PubMed Central

Bowman, Megan J.; Park, Wonkeun; Bauer, Philip J.; Udall, Joshua A.; Page, Justin T.; Raney, Joshua; Scheffler, Brian E.; Jones, Don. C.; Campbell, B. Todd

2013-01-01

An RNA-Seq experiment was performed using field grown well-watered and naturally rain fed cotton plants to identify differentially expressed transcripts under water-deficit stress. Our work constitutes the first application of the newly published diploid D5 Gossypium raimondii sequence in the study of tetraploid AD1 upland cotton RNA-seq transcriptome analysis. A total of 1,530 transcripts were differentially expressed between well-watered and water-deficit stressed root tissues, in patterns that confirm the accuracy of this technique for future studies in cotton genomics. Additionally, putative sequence based genome localization of differentially expressed transcripts detected A2 genome specific gene expression under water-deficit stress. These data will facilitate efforts to understand the complex responses governing transcriptomic regulatory mechanisms and to identify candidate genes that may benefit applied plant breeding programs. PMID:24324815

The Influence of Water Conservancy Projects on River Network Connectivity, A Case of Luanhe River Basin

NASA Astrophysics Data System (ADS)

Li, Z.; Li, C.

2017-12-01

Connectivity is one of the most important characteristics of a river, which is derived from the natural water cycle and determine the renewability of river water. The water conservancy project can change the connectivity of natural river networks, and directly threaten the health and stability of the river ecosystem. Based on the method of Dendritic Connectivity Index (DCI), the impacts from sluices and dams on the connectivity of river network are deeply discussed herein. DCI quantitatively evaluate the connectivity of river networks based on the number of water conservancy facilities, the connectivity of fish and geographical location. The results show that the number of water conservancy facilities and their location in the river basin have a great influence on the connectivity of the river network. With the increase of the number of sluices and dams, DCI is decreasing gradually, but its decreasing range is becoming smaller and smaller. The dam located in the middle of the river network cuts the upper and lower parts of the whole river network, and destroys the connectivity of the river network more seriously. Therefore, this method can be widely applied to the comparison of different alternatives during planning of river basins and then provide a reference for the site selection and design of the water conservancy project and facility concerned.

Determination of Iron Ion in the Water of a Natural Hot Spring Using Microfluidic Paper-based Analytical Devices.

PubMed

Ogawa, Kazuma; Kaneta, Takashi

2016-01-01

Microfluidic paper-based analytical devices (μPADs) were used to detect the iron ion content in the water of a natural hot spring in order to assess the applicability of this process to the environmental analysis of natural water. The μPADs were fabricated using a wax printer after the addition of hydroxylamine into the detection reservoirs to reduce Fe(3+) to Fe(2+), 1,10-phenanthroline for the forming of a complex, and poly(acrylic acid) for ion-pair formation with an acetate buffer (pH 4.7). The calibration curve of Fe(3+) showed a linearity that ranged from 100 to 1000 ppm in the semi-log plot whereas the color intensity was proportional to the concentration of Fe(3+) and ranged from 40 to 350 ppm. The calibration curve represented the daily fluctuation in successive experiments during four days, which indicated that a calibration curve must be constructed for each day. When freshly prepared μPADs were compared with stored ones, no significant difference was found. The μPADs were applied to the determination of Fe(3+) in a sample of water from a natural hot spring. Both the accuracy and the precision of the μPAD method were evaluated by comparisons with the results obtained via conventional spectrophotometry. The results of the μPADs were in good agreement with, but less precise than, those obtained via conventional spectrophotometry. Consequently, the μPADs offer advantages that include rapid and miniaturized operation, although the precision was poorer than that of conventional spectrophotometry.

Electron Shuttling by Dissolved Humic Substances: Using Fluorescence Spectroscopy to Move Beyond the Laboratory to Natural Lakes, Streams and Groundwaters

NASA Astrophysics Data System (ADS)

McKnight, D. M.

2017-12-01

Humic substances are an important class of reactive chemical species in natural waters, and one important role is their capacity to as an electron acceptor and/or electron shuttle to ferric iron present as solid phase ferric oxides. Several lines of evidence point to quinone-like moieties being the main redox active moieties that can be used by microbes in respiration. Concomitantly, the humic fraction of dissolved organic mater (DOM) contains the dominant fluorophores in many natural waters. Examination of excitation emission matrices (EEMs) across redox gradients in diverse aquatic systems show that the EEMs are generally red-shifted under reducing conditions, such as anoxic bottom waters in lakes and hypoxic waters in riparian wetlands. Furthermore, there is striking similarity between the humic fluorophores that are resolved by statistical analysis and the fluorescence spectra of model quinone compounds, with the more reduced species having red-shifted fluorescence spectra. This apparent red-shift can be quantified based on the distribution of apparently "quinone-like", "semi-quinone-like" and "hydroquinone-like" fluorophores determined by the PARAFAC statistical analysis. Because fluorescence spectroscopy can be applied at ambient DOM concentrations for samples that have been maintained in an anoxic condition, fluorescence spectroscopy can provide insight into the role of humic electron shuttling in natural systems. Examples are presented demosntrating the changing EEMs in anoxic bottomwaters in a lake in the McMurdo Dry Valleys following a major flood event and the role of organic material in the mobilization of arsenic in shallow groundwater in South East Asia.

Hydrology: The interdisciplinary science of water

NASA Astrophysics Data System (ADS)

Vogel, Richard M.; Lall, Upmanu; Cai, Ximing; Rajagopalan, Balaji; Weiskel, Peter K.; Hooper, Richard P.; Matalas, Nicholas C.

2015-06-01

We live in a world where biophysical and social processes are tightly coupled. Hydrologic systems change in response to a variety of natural and human forces such as climate variability and change, water use and water infrastructure, and land cover change. In turn, changes in hydrologic systems impact socioeconomic, ecological, and climate systems at a number of scales, leading to a coevolution of these interlinked systems. The Harvard Water Program, Hydrosociology, Integrated Water Resources Management, Ecohydrology, Hydromorphology, and Sociohydrology were all introduced to provide distinct, interdisciplinary perspectives on water problems to address the contemporary dynamics of human interaction with the hydrosphere and the evolution of the Earth's hydrologic systems. Each of them addresses scientific, social, and engineering challenges related to how humans influence water systems and vice versa. There are now numerous examples in the literature of how holistic approaches can provide a structure and vision of the future of hydrology. We review selected examples, which taken together, describe the type of theoretical and applied integrated hydrologic analyses and associated curricular content required to address the societal issue of water resources sustainability. We describe a modern interdisciplinary science of hydrology needed to develop an in-depth understanding of the dynamics of the connectedness between human and natural systems and to determine effective solutions to resolve the complex water problems that the world faces today. Nearly, every theoretical hydrologic model introduced previously is in need of revision to accommodate how climate, land, vegetation, and socioeconomic factors interact, change, and evolve over time.

Hydrology: The interdisciplinary science of water

USGS Publications Warehouse

Vogel, Richard M.; Lall, Upmanu; Cai, Ximing; Rajagopalan, Balaji; Weiskel, Peter K.; Hooper, Richard P.; Matalas, Nicholas C.

2015-01-01

We live in a world where biophysical and social processes are tightly coupled. Hydrologic systems change in response to a variety of natural and human forces such as climate variability and change, water use and water infrastructure, and land cover change. In turn, changes in hydrologic systems impact socioeconomic, ecological, and climate systems at a number of scales, leading to a coevolution of these interlinked systems. The Harvard Water Program, Hydrosociology, Integrated Water Resources Management, Ecohydrology, Hydromorphology, and Sociohydrology were all introduced to provide distinct, interdisciplinary perspectives on water problems to address the contemporary dynamics of human interaction with the hydrosphere and the evolution of the Earth’s hydrologic systems. Each of them addresses scientific, social, and engineering challenges related to how humans influence water systems and vice versa. There are now numerous examples in the literature of how holistic approaches can provide a structure and vision of the future of hydrology. We review selected examples, which taken together, describe the type of theoretical and applied integrated hydrologic analyses and associated curricular content required to address the societal issue of water resources sustainability. We describe a modern interdisciplinary science of hydrology needed to develop an in-depth understanding of the dynamics of the connectedness between human and natural systems and to determine effective solutions to resolve the complex water problems that the world faces today. Nearly, every theoretical hydrologic model introduced previously is in need of revision to accommodate how climate, land, vegetation, and socioeconomic factors interact, change, and evolve over time.

Biomimetic super-lyophobic and super-lyophilic materials applied for oil/water separation: a new strategy beyond nature.

PubMed

Wang, Ben; Liang, Weixin; Guo, Zhiguang; Liu, Weimin

2015-01-07

Oil spills and industrial organic pollutants have induced severe water pollution and threatened every species in the ecological system. To deal with oily water, special wettability stimulated materials have been developed over the past decade to separate oil-and-water mixtures. Basically, synergy between the surface chemical composition and surface topography are commonly known as the key factors to realize the opposite wettability to oils and water and dominate the selective wetting or absorption of oils/water. In this review, we mainly focus on the development of materials with either super-lyophobicity or super-lyophilicity properties in oil/water separation applications where they can be classified into four kinds as follows (in terms of the surface wettability of water and oils): (i) superhydrophobic and superoleophilic materials, (ii) superhydrophilic and under water superoleophobic materials, (iii) superhydrophilic and superoleophobic materials, and (iv) smart oil/water separation materials with switchable wettability. These materials have already been applied to the separation of oil-and-water mixtures: from simple oil/water layered mixtures to oil/water emulsions (including oil-in-water emulsions and water-in-oil emulsions), and from non-intelligent materials to intelligent materials. Moreover, they also exhibit high absorption capacity or separation efficiency and selectivity, simple and fast separation/absorption ability, excellent recyclability, economical efficiency and outstanding durability under harsh conditions. Then, related theories are proposed to understand the physical mechanisms that occur during the oil/water separation process. Finally, some challenges and promising breakthroughs in this field are also discussed. It is expected that special wettability stimulated oil/water separation materials can achieve industrial scale production and be put into use for oil spills and industrial oily wastewater treatment in the near future.

Analyzing anthropogenic pressures in soils of agro-ecological protected coastal wetlands in L'Albufera de Valencia Natural Park, Spain

NASA Astrophysics Data System (ADS)

Pascual-Aguilar, Juan Antonio; Andreu, Vicente; Gimeno, Eugenia; Picó, Yolanda

2013-04-01

Coastal wetlands, despite the importance of their environmental and ecological functions, are areas that suffer of great pressures. Most of them are produced by the rapid development of the surrounding artificial landscapes. Socio-economic factors such as population growth and urban-industrial surfaces expansion introduce pressures on the nearby environment affecting the quality of natural and agricultural landscapes. The present research analyses interconnections among landscapes (urban, agricultural and natural) under the hypothesis that urban-artificial impacts could be detected on soils of an agro-ecological protected area, L'Albufera de Valencia, Natural Park, located in the vicinity or the urban area of the City of Valencia, Spain. It has been developed based on Environmental Forensics criteria witch attend two types of anthropogenic pressures: (1) direct, due to artificialization of soil covers that produce anthropogenic soil sealing, and (2) indirect, which are related to water flows coming from urban populations throw artificial water networks (sewage and irrigation systems) and that ultimately will be identified by the presence of o emerging-pharmaceuticals contaminants in soils of the protected area. For the first case, soil sealing a methodology based on temporal comparison of two digital layers for the years 1991 and 2011 applying Geographical Information Systems and Landscapes Metrics were undertaken. To determine presence of emerging contaminants 15 soil samples within the Natural Park were analyzed applying liquid chromatography tandem mass spectrometry for the detection of 17 pharmaceutical compounds. Results show that both processes are present in the Natural Park with a clear geographical pattern. Either soil sealing or detection of pharmaceuticals are more intensive in the northern part of the study area. This is related to population density (detection of pharmaceuticals) and land cover conversion from agricultural and natural surfaces to artificial ones (soil sealing). Presence of pharmaceutical in soils of the Natural Park may be explained because of the interconnectivity of urban sewage waters (that after treatment) are incorporated in the irrigation network. Soil sealing expansion is more acute in the 1 kilometer stripe inside the boundary of the protected area. Acknowledgements: This work has been supported by the Spanish Ministry of Science and Innovation through the project CONSOLIDER-INGENIO 2010 (CSD2009)`, as well as by the Ministry and the European Regional Development Funds (ERDF) (projects CGL2011-29703-C02-00, CGL2011-29703-C02-01, CGL2011-29703-C02-02).

Development of water allocation Model Based on ET-Control and Its Application in Haihe River Basin

NASA Astrophysics Data System (ADS)

You, Jinjun; Gan, Hong; Gan, Zhiguo; Wang, Lin

2010-05-01

Traditionally, water allocation is to distribute water to different regions and sectors, without enough consideration on amount of water consumed after water distribution. Water allocation based on ET (evaporation and Transpiration) control changes this idea and emphasizes the absolute amount of evaporation and transpiration in specific area. With this ideology, the amount of ET involved the water allocation includes not only water consumed from the sectors, but the natural ET. Therefore, the water allocation consist of two steps, the first step is to estimate reasonable ET quantum in regions, then allocate water to more detailed regions and various sectors with the ET quantum according with the operational rules. To make qualified ET distribution and water allocation in various regions, a framework is put forward in this paper, in which two models are applied to analyze the different scenarios with predefined economic growth and ecological objective. The first model figures out rational ET objective with multi-objective analysis for compromised solution in economic growth and ecological maintenance. Food security and environmental protection are also taken as constraints in the optimization in the first model. The second one provides hydraulic simulation and water balance to allocate the ET objective to corresponding regions under operational rules. These two models are combined into an integrated ET-Control water allocation. Scenario analysis through the ET-Control Model could discover the relations between economy and ecology, farther to give suggestion on measures to control water use with condition of changing socio-economic growth and ecological objectives. To confirm the methodology, Haihe River is taken as a case to study. Rational water allocation is important branch of decision making on water planning and management in Haihe River Basin since water scarcity and deteriorating environment fights for water in this basin dramatically and reasonable water allocation between economy and ecology is a focus. Considering condition of water scarcity in Haihe River Basin, ET quota is taken as objective for water allocation in provinces to realize the requirement of water inflow into the Bohai Sea. Scenario analysis provides the results of water evaporation from natural water cycle and artificial use. A trade-off curve based on fulfilment of ecological and economic objectives in different scenarios discovers the competitive relation between human activities and nature.

A tentative discussion on the monitoring of water resources in China

NASA Astrophysics Data System (ADS)

Yang, Jianqing; Dai, Ning; Wu, Mengying; Wang, Guangsheng

2016-10-01

With the rapid economy development and social civilization progress, the Chinese Government also is improving ecological environmental conditions. More efforts have been made to solve water problems through the implementation of stringent water resources management, as a key government policy on water. Thus, monitoring of water resources has been strengthened, being a main component of the hydrological work in recent years. Compared with routine hydrological monitoring, water resources monitoring pays more attention to the quantity and quality variations of regional waters, to reflect the status of water in river basins and administrative regions. In this paper, the overall layout of the hydrometric network in China is presented, monitoring efforts of the natural water cycle and water consumptions are analyzed, methodologies of water resources monitoring, which are commonly applied in the country, are summed up. Taking the hydrometric network planning on interprovincial boundary waterbodies as example, a summary of the planning at interprovincial boundary river sections is presented. The planning can meet the need of water resources management of administrative divisions. It can also improve the overall water resources monitoring for the country.

Ice/water slurry blocking phenomenon at a tube orifice.

PubMed

Hirochi, Takero; Yamada, Shuichi; Shintate, Tuyoshi; Shirakashi, Masataka

2002-10-01

The phenomenon of ice-particle/water mixture blocking flow through a pipeline is a problem that needs to be solved before mixture flow can be applied for practical use in cold energy transportation in a district cooling system. In this work, the blocking mechanism of ice-particle slurry at a tube orifice is investigated and a criterion for blocking is presented. The cohesive nature of ice particles is shown to cause compressed plug type blocking and the compressive yield stress of a particle cluster is presented as a measure for the cohesion strength of ice particles.

Bioprocessing of ores: Application to space resources

NASA Technical Reports Server (NTRS)

Johansson, Karl R.

1992-01-01

The role of microorganisms in the oxidation and leaching of various ores (especially those of copper, iron, and uranium) is well known. This role is increasingly being applied by the mining, metallurgy, and sewage industries in the bioconcentration of metal ions from natural receiving waters and from waste waters. It is concluded that bioprocessing using bacteria in closed reactors may be a variable option for the recovery of metals from the lunar regolith. Obviously, considerable research must be done to define the process, specify the appropriate bacteria, determine the necessary conditions and limitations, and evaluate the overall feasibility.

Remote sensing techniques applied to multispectral recognition of the Aranjuez pilot zone

NASA Technical Reports Server (NTRS)

Lemos, G. L.; Salinas, J.; Rebollo, M.

1977-01-01

A rectangular (7 x 14 km) area 40 km S of Madrid was remote-sensed with a three-stage recognition process. Ground truth was established in the first phase, airborne sensing with a multispectral scanner and photographic cameras were used in the second phase, and Landsat satellite data were obtained in the third phase. Agronomic and hydrological photointerpretation problems are discussed. Color, black/white, and labeled areas are displayed for crop recognition in the land-use survey; turbidity, concentrations of pollutants and natural chemicals, and densitometry of the water are considered in the evaluation of water resources.

Potential of L-fucose isolated from Brown Seaweeds as Promising Natural Emulsifier compare to Carboxymethyl Cellulose (CMC)

NASA Astrophysics Data System (ADS)

Al-Baarri, A. N.; Legowo, A. M.; Widayat; Abduh, S. B. M.; Lestari, F. P.; Desnasari, D.; Santoso, I. P. M.

2018-02-01

L-fucose has been understood as sulfated polysaccharides and it could be extracted and fractionated from brown algae. These polysaccharides contains carbohydrate, sulfate, and protein that may be used as emulsifier. This research was aimed to study the emulsification properties of L-fucose through the determination of total dissolved solids (TDS), color CIE L*a*b* and stability of oil-in-water emulsion. As much as 0.5% of high concentrated L-fucose and 0.5% of carboxymethyl cellulose (CMC) were used as emulsifier in a 10% (v/v) oil-in-water (O/W) emulsion. The emulsifier was added to O/W emulsions and then heated at 72°C. Result of stability emulsion and TDS showed that L-fucose was comparable to the CMC but remarkable changed the color of O/W emulsion. Heating process significantly reduced the stability O/W emulsion when L-fucose was applied. As conclusion, L-fucose might be used as natural emulsifier in O/W emulsion but in the low heat treatment of food processing. This study may provide valuable information for utilizing natural emulsifier from abundant resources from nature.

Integrating an agent-based model into a large-scale hydrological model for evaluating drought management in California

NASA Astrophysics Data System (ADS)

Sheffield, J.; He, X.; Wada, Y.; Burek, P.; Kahil, M.; Wood, E. F.; Oppenheimer, M.

2017-12-01

California has endured record-breaking drought since winter 2011 and will likely experience more severe and persistent drought in the coming decades under changing climate. At the same time, human water management practices can also affect drought frequency and intensity, which underscores the importance of human behaviour in effective drought adaptation and mitigation. Currently, although a few large-scale hydrological and water resources models (e.g., PCR-GLOBWB) consider human water use and management practices (e.g., irrigation, reservoir operation, groundwater pumping), none of them includes the dynamic feedback between local human behaviors/decisions and the natural hydrological system. It is, therefore, vital to integrate social and behavioral dimensions into current hydrological modeling frameworks. This study applies the agent-based modeling (ABM) approach and couples it with a large-scale hydrological model (i.e., Community Water Model, CWatM) in order to have a balanced representation of social, environmental and economic factors and a more realistic representation of the bi-directional interactions and feedbacks in coupled human and natural systems. In this study, we focus on drought management in California and considers two types of agents, which are (groups of) farmers and state management authorities, and assumed that their corresponding objectives are to maximize the net crop profit and to maintain sufficient water supply, respectively. Farmers' behaviors are linked with local agricultural practices such as cropping patterns and deficit irrigation. More precisely, farmers' decisions are incorporated into CWatM across different time scales in terms of daily irrigation amount, seasonal/annual decisions on crop types and irrigated area as well as the long-term investment of irrigation infrastructure. This simulation-based optimization framework is further applied by performing different sets of scenarios to investigate and evaluate the effectiveness of different water management strategies and how policy interventions will facilitate drought adaptation in California.

Network global navigation satellite system survey to harmonize water-surface elevation data for the Rainy River Basin

USGS Publications Warehouse

Ziegeweid, Jeffrey R.; Silliker, R. Jason; Densmore, Brenda K.; Krahulik, Justin

2016-08-15

Continuously recording water-level streamgages in Rainy Lake and Namakan Reservoir are used to regulate water levels according to rule curves established in 2000 by the International Joint Commission; however, water levels at streamgages were referenced to a variety of vertical datums, confounding efforts to model the flow of water through the system, regulate water levels during periods of high inflow, and evaluate the effectiveness of the rule curves. In October 2014, the U.S. Geological Survey, Natural Resources Canada, International Joint Commission, and National Park Service began a joint field study with the goal of obtaining precise elevations referenced to a uniform vertical datum for all reference marks used to set water levels at streamgages throughout Rainy Lake and Namakan Reservoir. This report was prepared by the U.S. Geological Survey in cooperation with Natural Resources Canada, International Joint Commission, and National Park Service.Three field crews deployed Global Navigation Satellite System receivers statically over 16 reference marks colocated with active and discontinued water-level streamgages throughout Rainy River, Rainy Lake, Namakan Reservoir, and select tributaries of Rainy Lake and Namakan Reservoir. A Global Navigation Satellite System receiver also was deployed statically over a National Geodetic Survey cooperative base network control station for use as a quality-control reference mark. Satellite data were collected simultaneously during a 5-day period and processed independently by the U.S. Geological Survey and Natural Resources Canada to obtain accurate positioning and elevations for the 17 surveyed reference marks. Processed satellite data were used to convert published water levels to elevations above sea level referenced to the Canadian Geodetic Vertical Datum of 2013 in order to compare water-surface elevations referenced to a uniform vertical datum throughout the study area. In this report, an “offset” refers to the correction applied to published data from a particular streamgage to produce elevation data referenced to a specified vertical datum.Offsets were applied to water-level data from surveyed streamgages to further evaluate the accuracy and utility of updated reference mark elevations presented in this report. Daily mean water levels from active streamgages surveyed in this study were converted to water-surface elevations referenced to the Canadian Geodetic Vertical Datum of 2013. Graphical comparisons of water-surface elevations for streamgages in Namakan Reservoir, Rainy Lake, and selected rivers are presented (referencing the Canadian Geodetic Vertical Datum of 2013). Offsets presented in this report can be used in the evaluation of rule curves and in flood damage curves that fully assess the benefits of one regulation approach over another. In addition, offsets may be used to calibrate hydraulic models developed for four narrows that connect lakes of Namakan Reservoir, refine digital elevation models, and support modeling studies designed to assess the effects of rule curves on aquatic vegetation, benthic invertebrates, northern pike, and walleye.

Salty bark as a soil amendment

Treesearch

W.B. Bollen

1971-01-01

Bark from Douglas-fir logs floated in sea water contained 0.75 to 1.94 percent salt (NaCl). Leaching by natural and simulated rainfall and by soaking readily removed this salt. Bush bean and tomato plants were grown in the greenhouse on a sandy loam soil to which bark of three different proportions of salt was applied as a mulch and as an incorporation at the rate of...

[Environmental safety assessment on the new super absorbent polymers applied into a soil-Chinese cabbage system].

PubMed

Li, Xi; He, Ji-Zheng; Zheng, Yuan-Ming; Zheng, Ming-Lan

2014-02-01

Super absorbent polymers (SAPs), a new water retention material, have a potential for application in water-saving agricultural production. In this study, we investigated the effects of SAPs, synthesized from natural plant extracts, on Chinese cabbage fresh weight, soil water content, soil water stable aggregates, soil microbial biomass (carbon) and soil microbial respiration under three water conditions (excessive, normal and deficient) and two SAPs application strategies (bulk treatment and spraying treatment). The results showed that the SAPs significantly promoted the soil water content, water-stable aggregates (> 0.25 mm) and the soil microbial activities, especially under the water deficient conditions. Meanwhile, SAP application strategy was of great significance to the effects on Chinese cabbage and soil properties. Compared with the control treatment under normal water condition, spraying treatment of Jaguar C (S-JC) could reduce irrigation water amount by about 25% without reducing the crop production. Furthermore, compared with the control treatment under the same water condition with S-JC (deficient), it could increase Chinese cabbage production by 287%. Thus, SAPs is an environmental friendly water-saving technique in agricultural production.

Teaching Sustainable Water Resources and Low Impact Development: A Project Centered Course for First-Year Undergraduates

NASA Astrophysics Data System (ADS)

Cianfrani, C. M.

2009-12-01

Teaching Sustainable Water Resources and Low Impact Development: A Project Centered Course for First-Year Undergraduates Christina M. Cianfrani Assistant Professor, School of Natural Science, Hampshire College, 893 West Avenue, Amherst, MA 01002 Sustainable water resources and low impact development principles are taught to first-year undergraduate students using an applied design project sited on campus. All students at Hampshire College are required to take at least one natural science course during their first year as part of their liberal arts education. This requirement is often met with resistance from non-science students. However, ‘sustainability’ has shown to be a popular topic on campus and ‘Sustainable Water Resources’ typically attracts ~25 students (a large class size for Hampshire College). Five second- or third-year students are accepted in the class as advanced students and serve as project leaders. The first-year students often enter the class with only basic high school science background. The class begins with an introduction to global water resources issues to provide a broad perspective. The students then analyze water budgets, both on a watershed basis and a personal daily-use basis. The students form groups of 4 to complete their semester project. Lectures on low impact design principles are combined with group work sessions for the second half of the semester. Students tour the physical site located across the street from campus and begin their project with a site analysis including soils, landcover and topography. They then develop a building plan and identify preventative and mitigative measures for dealing with stormwater. Each group completes TR-55 stormwater calculations for their design (pre- and post-development) to show the state regulations for quantity will be met with their design. Finally, they present their projects to the class and prepare a formal written report. The students have produced a wide variety of creative, mostly practical designs. Student feedback about the course has included high praise for the applied nature of the project as well as the use of advanced students to lead the groups and help provide guidance throughout the project. Example of low impact development using clustered housing, rain gardens (small dots), green roofs (circles on house sites), vegetated swales along roadways, infiltration area, and a reforested buffer (along right edge).

Regional Scale High Resolution δ18O Prediction in Precipitation Using MODIS EVI

PubMed Central

Huang, Cho-Ying; Wang, Chung-Ho; Lin, Shou-De; Lo, Yi-Chen; Huang, Bo-Wen; Hatch, Kent A.; Shiu, Hau-Jie; You, Cheng-Feng; Chang, Yuan-Mou; Shen, Sheng-Feng

2012-01-01

The natural variation in stable water isotope ratio data, also known as water isoscape, is a spatiotemporal fingerprint and a powerful natural tracer that has been widely applied in disciplines as diverse as hydrology, paleoclimatology, ecology and forensic investigation. Although much effort has been devoted to developing a predictive water isoscape model, it remains a central challenge for scientists to generate high accuracy, fine scale spatiotemporal water isoscape prediction. Here we develop a novel approach of using the MODIS-EVI (the Moderate Resolution Imagining Spectroradiometer-Enhanced Vegetation Index), to predict δ18O in precipitation at the regional scale. Using a structural equation model, we show that the EVI and precipitated δ18O are highly correlated and thus the EVI is a good predictor of precipitated δ18O. We then test the predictability of our EVI-δ18O model and demonstrate that our approach can provide high accuracy with fine spatial (250×250 m) and temporal (16 days) scale δ18O predictions (annual and monthly predictabilities [r] are 0.96 and 0.80, respectively). We conclude the merging of the EVI and δ18O in precipitation can greatly extend the spatial and temporal data availability and thus enhance the applicability for both the EVI and water isoscape. PMID:23029053

Application of a Groundwater Modeling Tool for Managing Hydrologically Connected Area in State of Nebraska, US

NASA Astrophysics Data System (ADS)

Li, R.; Flyr, B.; Bradley, J.; Pun, M.; Schneider, J.; Wietjes, J.; Chinta, S.

2014-12-01

Determination of the nature and degree of hydrologically connected groundwater and surface water resources is of paramount importance to integrated water management within the State of Nebraska to understand the impact of water uses on available supplies, such as depletion of streams and aquifers caused by groundwater pumping. The ability to quantify effects of surface water-groundwater hydrologic connection and interactions, is regarded as one of the most important steps towards effectively managing water resources in Nebraska and provides the basis for designating management areas. Designation of management areas allows the state and other management entities to focus various efforts and resources towards those projects that have the greatest impact to water users. Nebraska Department of Natural Resources (NDNR) developed a groundwater modeling tool, Cycle Well Analysis, to determine the areas defined to have a high degree of connectivity between groundwater and surface water (in accordance with the state regulations). This tool features two graphic user interfaces to allow the analysis to be fully compatible with most MODFLOW-based numerical groundwater models currently utilized by NDNR. Case studies showed that the tool, in combination of Geographic Information Systems (GIS), can be used to quantify the degree of stream depletion and delineate the boundary of hydrologically connected areas within different political boundaries and subbasins in Nebraska. This approach may be applied to other regions with similar background and need for integrated water management.

Trace metal determination in natural waters by automated solid phase extraction system and ICP-MS: the influence of low level Mg and Ca.

PubMed

Wang, Bo-Shian; Lee, Chih-Ping; Ho, Tung-Yuan

2014-10-01

A fully automated high pressure pretreatment system with Nobias Chelate-PA1 resin (PA1) was developed for trace metal determination by ICP-MS in natural waters. By varying the concentrations of Mg and Ca to mimic the concentrations in the eluate obtained by PA1 or iminodiacetate type resins, the overall analytical performance of the system was assessed for the determination of Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Cd, Ag, Pb and REE. Comparing with the low mM level Mg and Ca (both ranging from 1 to 4mM) eluted by iminodiacetate type resins, the eluate obtained by PA1 contains sub-μM level Mg and Ca, which remarkably decrease matrix effect in ICP-MS analysis and significantly improve the analytical performance. With recovery better than 90% for most the trace metals examined, the accuracy was further verified through the analysis of five natural water reference materials with salinity spanning from 0 to 35‰. We have successfully applied the pretreatment system to determine trace metals in the seawater samples collected in the Western Philippine Sea through Taiwan GEOTRACES cruise. Copyright © 2014 Elsevier B.V. All rights reserved.

A hybrid fuzzy logic and extreme learning machine for improving efficiency of circulating water systems in power generation plant

NASA Astrophysics Data System (ADS)

Aziz, Nur Liyana Afiqah Abdul; Siah Yap, Keem; Afif Bunyamin, Muhammad

2013-06-01

This paper presents a new approach of the fault detection for improving efficiency of circulating water system (CWS) in a power generation plant using a hybrid Fuzzy Logic System (FLS) and Extreme Learning Machine (ELM) neural network. The FLS is a mathematical tool for calculating the uncertainties where precision and significance are applied in the real world. It is based on natural language which has the ability of "computing the word". The ELM is an extremely fast learning algorithm for neural network that can completed the training cycle in a very short time. By combining the FLS and ELM, new hybrid model, i.e., FLS-ELM is developed. The applicability of this proposed hybrid model is validated in fault detection in CWS which may help to improve overall efficiency of power generation plant, hence, consuming less natural recourses and producing less pollutions.

Sprawling nursery unveils propane backup for natural gas boilers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-02-01

First, take the most authoritative policy- making body in the pervasive problem area of Southern California air pollution (South Coast Air Quality Management District - SCAQMD). Then apply that organization's recently- enacted regulation prohibiting the use of diesel fuel in boilers to a well-known commercial establishment. The result is an alternative fuel story, that's too engaging to overlook. Monrovia Nursery, a 65-year-old, 500-acre wholesale growing facility in Azusa, Calif., has installed two 200-hp Dixon boilers, a 14 MMBtuh Sam Dick Industries vaporizer, and six 1150-gal. tanks on the property for the use of propane as a backup fuel. While themore » nursery ordinarily uses natural gas for water heating, there are times during the winter when the supply may be curtailed or interrupted. It is then that propane would be used to heat water to keep more than 1200 varieties of plants growing as they should.« less

Redox Conditions in Selected Principal Aquifers of the United States

USGS Publications Warehouse

McMahon, P.B.; Cowdery, T.K.; Chapelle, F.H.; Jurgens, B.C.

2009-01-01

Reduction/oxidation (redox) processes affect the quality of groundwater in all aquifer systems. Redox processes can alternately mobilize or immobilize potentially toxic metals associated with naturally occurring aquifer materials, contribute to the degradation or preservation of anthropogenic contami-nants, and generate undesirable byproducts, such as dissolved manganese (Mn2+), ferrous iron (Fe2+), hydrogen sulfide (H2S), and methane (CH4). Determining the kinds of redox processes that occur in an aquifer system, documenting their spatial distribution, and understanding how they affect concentrations of natural or anthropogenic contaminants are central to assessing and predicting the chemical quality of groundwater. This Fact Sheet extends the analysis of U.S. Geological Survey authors to additional principal aquifer systems by applying a framework developed by the USGS to a larger set of water-quality data from the USGS national water databases. For a detailed explanation, see the 'Introduction' in the Fact Sheet.

Multicriteria decision analysis applied to Glen Canyon Dam

USGS Publications Warehouse

Flug, M.; Seitz, H.L.H.; Scott, J.F.

2000-01-01

Conflicts in water resources exist because river-reservoir systems are managed to optimize traditional benefits (e.g., hydropower and flood control), which are historically quantified in economic terms, whereas natural and environmental resources, including in-stream and riparian resources, are more difficult or impossible to quantify in economic terms. Multicriteria decision analysis provides a quantitative approach to evaluate resources subject to river basin management alternatives. This objective quantification method includes inputs from special interest groups, the general public, and concerned individuals, as well as professionals for each resource considered in a trade-off analysis. Multicriteria decision analysis is applied to resources and flow alternatives presented in the environmental impact statement for Glen Canyon Dam on the Colorado River. A numeric rating and priority-weighting scheme is used to evaluate 29 specific natural resource attributes, grouped into seven main resource objectives, for nine flow alternatives enumerated in the environmental impact statement.

Topical vitamin C: a useful agent for treating photoaging and other dermatologic conditions.

PubMed

Farris, Patricia K

2005-07-01

Cosmeceuticals containing antioxidants are among the most popular antiaging remedies. Topically applied antioxidants exert their benefits by offering protection from damaging free radicals produced when skin is exposed to ultraviolet light or allowed to age naturally. Vitamin C is a naturally occurring potent water-soluble antioxidant. Accordingly, it has been incorporated into a variety of cosmeceuticals designed to protect and rejuvenate photoaged skin. This article reviews the scientific data and clinical studies supporting the use of topically applied vitamin C for treating photoaged skin. Other innovative uses for vitamin C cosmeceuticals are also discussed. A significant body of scientific research supports the use of cosmeceuticals containing vitamin C. Cutaneous benefits include promoting collagen synthesis, photoprotection from ultraviolet A and B, lightening hyperpigmentation, and improvement of a variety of inflammatory dermatoses. Because of the diverse biologic effects of this compound, topical vitamin C has become a useful part of the dermatologist's armamentarium.

Natural Poly- and Oligosaccharides as Novel Delivery Systems for Plant Protection Compounds.

PubMed

Selyutina, O Yu; Apanasenko, I E; Khalikov, S S; Polyakov, N E

2017-08-09

To increase the bioavailability of plant protection products, we have applied a new approach based on noncovalent association with natural water-soluble polysaccharides and oligosaccharides as delivery systems (DSs). The mechanochemical technique has been applied to prepare the solid-state nanodispersed compositions of antidote 1,8-naphthalic anhydride (NA) with arabinogalactan, sodium salt of carboxymethylcellulose, and glycyrrhizin as DSs. The effect of DSs on the solubility and the penetration of NA into the seeds of barley and wheat has been investigated by various physicochemical techniques. All DSs considerably enhance the solubility of NA and improve its penetration into the grain. The influence of polysaccharides and oligosaccharides on artificial lipid membranes was studied by the NMR relaxation method. It was concluded that the effect of polysaccharides and oligosaccharides on the penetration efficacy of plant protection products might be associated with the detected solubility enhancement and the affinity of DSs to the surface of cell membranes.

Drivers of Change in Managed Water Resources: Modeling the Impacts of Climate and Socioeconomic Changes Using the US Midwest as a Case Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voisin, Nathalie; Leung, Lai-Yung R.; Hejazi, Mohamad I.

A global integrated assessment model including a water-demand model driven by socio-economics, is coupled in a one-way fashion with a land surface hydrology – routing – water resources management model. The integrated modeling framework is applied to the U.S. Upper Midwest (Missouri, Upper Mississippi, and Ohio) to advance understanding of the regional impacts of climate and socio-economic changes on integrated water resources. Implications for future flow regulation, water supply, and supply deficit are investigated using climate change projections with the B1 and A2 emission scenarios, which affect both natural flow and water demand. Changes in water demand are driven bymore » socio-economic factors, energy and food demands, global markets and prices. The framework identifies the multiple spatial scales of interactions between the drivers of changes (natural flow and water demand) and the managed water resources (regulated flow, supply and supply deficit). The contribution of the different drivers of change are quantified regionally, and also evaluated locally, using covariances. The integrated framework shows that water supply deficit is more predictable over the Missouri than the other regions in the Midwest. The predictability of the supply deficit mostly comes from long term changes in water demand although changes in runoff has a greater contribution, comparable to the contribution of changes in demand, over shorter time periods. The integrated framework also shows that spatially, water demand drives local supply deficit. Using elasticity, the sensitivity of supply deficit to drivers of change is established. The supply deficit is found to be more sensitive to changes in runoff than to changes in demand regionally. It contrasts with the covariance analysis that shows that water demand is the dominant driver of supply deficit over the analysed periods. The elasticity indicates the level of mitigation needed to control the demand in order to reduce the vulnerability of the integrated system in future periods. The elasticity analyses also emphasize the need to address uncertainty with respect to changes in natural flow in integrated assessment.« less

Management of the Israeli National Water System under Uncertainty

NASA Astrophysics Data System (ADS)

Shamir, U.; Housh, M.; Ostfeld, A.; Zaide, M.

2009-12-01

Uncertainty in our region is due to the natural variability of hydrological patterns, with recurring extended droughts, reduced average and broadening variability of recharge that seem to indicate the effect of climate change, as well as to deterioration of water quality in the natural sources, to population growth and distribution, to shifting demand patterns among consumer sectors, and to expected future regional water agreements. These factors combine to create a challenging environment in which highly stressed water resources and water systems have to be developed, operated and managed. The natural sources have been used to their sustainable capacity and often beyond. The main policy responses are a shift of fresh water from agriculture to the cities, replacing it with treated wastewater for irrigation, and a major program for construction of sea-water desalination plants and the associated infrastructure needed for its integration into the supply systems. Organizational reforms, regulation, and demand management options are also being developed, including full-cost pricing. Management of the water resources and systems under these conditions requires a long-term perspective. The methodologies for supporting management decisions that have been used to date by the Israeli Water Authority include evaluation by scenarios, simulation, and optimization with sensitivity analysis. We review existing approaches and models for management of the Israeli water system (Zaide 2006) and then present some new methodologies for addressing operational decisions under hydrological uncertainty, which include generation of tradeoffs between the expected value and variability of the outcomes, and an Info-Gap (Ben-Haim 2006) based approach. These methodologies are demonstrated on examples that emulate portions of a regional water system and are then applied to the Israeli National Water System. Ben-Haim, Y. (2006) Info-Gap Theory: Decisions under Severe Uncertainty, 2nd Ed., Academic Press, London. Zaide, M. (2006) A Model for Management of Water Quantity and Quality in the Israeli National System", MSc Thesis, Faculty of Civil Engineering, Technion. http://urishamir.wri.technion.ac.il/files/documents/Miki%20Zaide%20-%20Thesis%20Final%2015.03.06.pdf

The effects of agriculture on the volcanic aquifers of the canary islands

NASA Astrophysics Data System (ADS)

Custodio, E.; Guerra, J. A.; Jiménez, J.; Medina, J. A.; Soler, C.

1983-12-01

Agriculture is a basic economic activity in the Canary Islands, a Spanish region in the Atlantic Ocean, facing the Sahara. The main crops are bananas, tomatoes, and other special ones suitable for exportation. Fertilizers are applied in high quantities on the scarce land available. The relatively good vertical permeability of the soils favors the deep infiltration of irrigation return flows. Water is obtained by an extraordinary net of shaft wells and water galleries, supplemented when possible by surface reservoirs in the deep gullies. Water is distributed by an extensive network of pipes and canals, allowing the transportation of water to virtually any point from any water source. Water quality is widely variable, from almost rain water to brackish, with a high frequency of sodium bicarbonate types. Return flows, especially when water is applied with good irrigation techniques and the original quality is poor, are saline and contain chemicals leached from the fertilizers. On Tenerife Island, most of the return flows go to coastal aquifers, while most of the water comes from high-altitude water galleries. Agricultural pollution is not generally appraised, but it exists. It can be masked by the frequent, high natural nitrate content in groundwater. On Gran Canaria Island, since water comes mainly from deep shaft wells near the irrigated areas, the nitrate pollution is much more clear. On La Palma Island, besides the nitrate pollution, a potassium pollution of agricultural origin has been mentioned. Other situations on the remaining islands are also discussed. It can be concluded that agriculture is a big concern for the water quality in many areas and impairs its suitability for other uses. Because of the great depth of the water table, the nitrate pollution may not become obvious for many years, especially for the deep-water galleries.

Historical review of the international water-resources program of the U.S. Geological Survey, 1940-70

USGS Publications Warehouse

Taylor, George C.

1976-01-01

The review describes the history of the U.S. Geological Survey 's (USGS) activities in international water-resources investigations and institutional development as well as exchange in scientific and applied hydrology during 1940-70. The bulk of these activities has been carried out under the auspices of the U.S. Department of State, U.S. Agency for International Development and its predecessors, the United Nations and its specialized agencies, and the regional intergovernmental agencies. The central objectives of the USGS ' international water-resources activities have been to strengthen the administrative, staff, and operational functions of counterpart governmental hydrological and water-resources agencies; to improve the skills and capabilities of host-country scientific, engineering, and technical personnel; to exchange research specialists and publications in the sharing of advances in hydrological knowledge and methodology; and to participate in mutually beneficial international organizations, symposia, conferences, seminars, and special programs dedicated to various aspects of scientific and applied hydrology. Between 1940 and 1970, USGS hydrogeologists, water chemists, engineers, and hydrologists completed 340 short- and long-term project-oriented international assignments in some 80 host countries. During the same time more than 428 water scientists, engineers, and technicians from 60 countries have received academic and in-service training through USGS water-resources facilities in the United States. Also in this period some 336 reports of a technical and scientific nature have resulted from water-resources projects in the U.S bilateral program. (Woodard-USGS)

Requiring Pollutant Discharge Permits for Pesticide Applications that Deposit Residues in Surface Waters

PubMed Central

Centner, Terence; Eberhart, Nicholas

2014-01-01

Agricultural producers and public health authorities apply pesticides to control pests that damage crops and carry diseases. Due to the toxic nature of most pesticides, they are regulated by governments. Regulatory provisions require pesticides to be registered and restrictions operate to safeguard human health and the environment. Yet pesticides used near surface waters pose dangers to non-target species and drinking water supplies leading some governments to regulate discharges of pesticides under pollution discharge permits. The dual registration and discharge permitting provisions are burdensome. In the United States, agricultural interest groups are advancing new legislation that would exempt pesticide residues from water permitting requirements. An analysis of the dangers posed by pesticide residues in drinking water leads to a conclusion that both pesticide registration and pollutant discharge permitting provisions are needed to protect human health and aquatic species. PMID:24814945

Several problems in regard to national land management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong Wenlang

1983-09-21

This article examines several problems with regard to land management in China. National land management is defined as development of the territorial land (including the earth's surface and underground), territorial waters and territorial air space under the jurisdiction of a sovereign country. The Chinese State Council established the Bureau of National Land Management in 1981. Areas of concern include natural resources, or land resources (including continental land, rivers and lakes, territorial waters and what is beneath the waters and the airspace above the waters, also the continental shelves), mineral resources and biological resources; social resources, which include human resources, intellectualmore » resources, social and cultural traditions, and the material and technical foundations of a society. Untapped resources of land, waters, forests, grasslands and minerals are to be developed through reclamation, mining, and engineering projects. Geography and national land economics are the theoretical and applied sciences directly related to national land management.« less

Description, Properties, and Degradation of Selected Volatile Organic Compounds Detected in Ground Water--A Review of Selected Literature

USGS Publications Warehouse

Lawrence, Stephen J.

2006-01-01

This report provides abridged information describing the most salient properties and biodegradation of 27 chlorinated volatile organic compounds detected during ground-water studies in the United States. This information is condensed from an extensive list of reports, papers, and literature published by the U.S. Government, various State governments, and peer-reviewed journals. The list includes literature reviews, compilations, and summaries describing volatile organic compounds in ground water. This report cross-references common names and synonyms associated with volatile organic compounds with the naming conventions supported by the International Union of Pure and Applied Chemistry. In addition, the report describes basic physical characteristics of those compounds such as Henry's Law constant, water solubility, density, octanol-water partition (log Kow), and organic carbon partition (log Koc) coefficients. Descriptions and illustrations are provided for natural and laboratory biodegradation rates, chemical by-products, and degradation pathways.

Applying of Factor Analyses for Determination of Trace Elements Distribution in Water from River Vardar and Its Tributaries, Macedonia/Greece

PubMed Central

Popov, Stanko Ilić; Stafilov, Trajče; Šajn, Robert; Tănăselia, Claudiu; Bačeva, Katerina

2014-01-01

A systematic study was carried out to investigate the distribution of fifty-six elements in the water samples from river Vardar (Republic of Macedonia and Greece) and its major tributaries. The samples were collected from 27 sampling sites. Analyses were performed by mass spectrometry with inductively coupled plasma (ICP-MS) and atomic emission spectrometry with inductively coupled plasma (ICP-AES). Cluster and R mode factor analysis (FA) was used to identify and characterise element associations and four associations of elements were determined by the method of multivariate statistics. Three factors represent the associations of elements that occur in the river water naturally while Factor 3 represents an anthropogenic association of the elements (Cd, Ga, In, Pb, Re, Tl, Cu, and Zn) introduced in the river waters from the waste waters from the mining and metallurgical activities in the country. PMID:24587756

Applying of factor analyses for determination of trace elements distribution in water from Vardar and its tributaries, Macedonia/Greece.

PubMed

Popov, Stanko Ilić; Stafilov, Trajče; Sajn, Robert; Tănăselia, Claudiu; Bačeva, Katerina

2014-01-01

A systematic study was carried out to investigate the distribution of fifty-six elements in the water samples from river Vardar (Republic of Macedonia and Greece) and its major tributaries. The samples were collected from 27 sampling sites. Analyses were performed by mass spectrometry with inductively coupled plasma (ICP-MS) and atomic emission spectrometry with inductively coupled plasma (ICP-AES). Cluster and R mode factor analysis (FA) was used to identify and characterise element associations and four associations of elements were determined by the method of multivariate statistics. Three factors represent the associations of elements that occur in the river water naturally while Factor 3 represents an anthropogenic association of the elements (Cd, Ga, In, Pb, Re, Tl, Cu, and Zn) introduced in the river waters from the waste waters from the mining and metallurgical activities in the country.

Use of the Delphi method in resolving complex water resources issues

USGS Publications Warehouse

Taylor, J.G.; Ryder, S.D.

2003-01-01

The tri-state river basins, shared by Georgia, Alabama, and Florida, are being modeled by the U.S. Fish and Wildlife Service and the U.S. Army Corps of Engineers to help facilitate agreement in an acrimonious water dispute among these different state governments. Modeling of such basin reservoir operations requires parallel understanding of several river system components: hydropower production, flood control, municipal and industrial water use, navigation, and reservoir fisheries requirements. The Delphi method, using repetitive surveying of experts, was applied to determine fisheries' water and lake-level requirements on 25 reservoirs in these interstate basins. The Delphi technique allowed the needs and requirements of fish populations to be brought into the modeling effort on equal footing with other water supply and demand components. When the subject matter is concisely defined and limited, this technique can rapidly assess expert opinion on any natural resource issue, and even move expert opinion toward greater agreement.

Feasibility of using LANDSAT images of vegetation cover to estimate effective hydraulic properties of soils

NASA Technical Reports Server (NTRS)

Eagleson, P. S.

1985-01-01

Research activities conducted from February 1, 1985 to July 31, 1985 and preliminary conclusions regarding research objectives are summarized. The objective is to determine the feasibility of using LANDSAT data to estimate effective hydraulic properties of soils. The general approach is to apply the climatic-climax hypothesis (Ealgeson, 1982) to natural water-limited vegetation systems using canopy cover estimated from LANDSAT data. Natural water-limited systems typically consist of inhomogeneous vegetation canopies interspersed with bare soils. The ground resolution associated with one pixel from LANDSAT MSS (or TM) data is generally greater than the scale of the plant canopy or canopy clusters. Thus a method for resolving percent canopy cover at a subpixel level must be established before the Eagleson hypothesis can be tested. Two formulations are proposed which extend existing methods of analyzing mixed pixels to naturally vegetated landscapes. The first method involves use of the normalized vegetation index. The second approach is a physical model based on radiative transfer principles. Both methods are to be analyzed for their feasibility on selected sites.

Using NASA's GRACE and SMAP satellites to measure human impacts on the water cycle

NASA Astrophysics Data System (ADS)

Reager, J. T., II; Castle, S.; Turmon, M.; Famiglietti, J. S.; Fournier, S.

2017-12-01

Two satellite missions, the Gravity Recovery and Climate Experiment (GRACE) mission and the Soil Moisture Active Passive (SMAP) mission are enabling the measurement of the dynamic state of the water cycle globally, offering a unique opportunity for the study of human impacts on terrestrial hydrology and an opportunity to quantify the direct augmentation of natural cycles by human activities. While many model-data fusion studies aim to apply observations to improve model performance, we present recent studies on measuring the multi-scale impacts of human activities by differencing or contrasting model simulations and observations. Results that will be presented include studies on: the measurement of human impacts on evapotranspiration in the Colorado River Basin; the estimation of the human portion of groundwater depletion in the Southwestern U.S.; and the influence of irrigation on runoff generation in the Mississippi River basin. Each of these cases has a unique implications for the sustainable use of natural resources by humans, and indicate the relevant extent and magnitude of human influence on natural processes, suggesting their importance for inclusion in hydrology and land-surface models.

Gas Marbles: Much Stronger than Liquid Marbles

NASA Astrophysics Data System (ADS)

Timounay, Yousra; Pitois, Olivier; Rouyer, Florence

2017-06-01

Enwrapping liquid droplets with hydrophobic particles allows the manufacture of so-called "liquid marbles" [Aussillous and Quéré Nature (London) 411, 924 (2001); , 10.1038/35082026Mahadevan Nature (London)411, 895 (2001), 10.1038/35082164]. The recent intensive research devoted to liquid marbles is justified by their very unusual physical and chemical properties and by their potential for various applications, from microreactors to water storage, including water pollution sensors [Bormashenko Curr. Opin. Colloid Interface Sci. 16, 266 (2011), 10.1016/j.cocis.2010.12.002]. Here we demonstrate that this concept can be successfully applied for encapsulating and protecting small gas pockets within an air environment. Similarly to their liquid counterparts, those new soft-matter objects, that we call "gas marbles," can sustain external forces. We show that gas marbles are surprisingly tenfold stronger than liquid marbles and, more importantly, they can sustain both positive and negative pressure differences. This magnified strength is shown to originate from the strong cohesive nature of the shell. Those interesting properties could be exploited for imprisoning valuable or polluted gases or for designing new aerated materials.

Gas Marbles: Much Stronger than Liquid Marbles.

PubMed

Timounay, Yousra; Pitois, Olivier; Rouyer, Florence

2017-06-02

Enwrapping liquid droplets with hydrophobic particles allows the manufacture of so-called "liquid marbles" [Aussillous and Quéré Nature (London) 411, 924 (2001); NATUAS0028-083610.1038/35082026Mahadevan Nature (London)411, 895 (2001)NATUAS0028-083610.1038/35082164]. The recent intensive research devoted to liquid marbles is justified by their very unusual physical and chemical properties and by their potential for various applications, from microreactors to water storage, including water pollution sensors [Bormashenko Curr. Opin. Colloid Interface Sci. 16, 266 (2011)COCSFL1359-029410.1016/j.cocis.2010.12.002]. Here we demonstrate that this concept can be successfully applied for encapsulating and protecting small gas pockets within an air environment. Similarly to their liquid counterparts, those new soft-matter objects, that we call "gas marbles," can sustain external forces. We show that gas marbles are surprisingly tenfold stronger than liquid marbles and, more importantly, they can sustain both positive and negative pressure differences. This magnified strength is shown to originate from the strong cohesive nature of the shell. Those interesting properties could be exploited for imprisoning valuable or polluted gases or for designing new aerated materials.

A software framework for assessing the resilience of drinking water systems to disasters with an example earthquake case study

DOE PAGES

Klise, Katherine A.; Bynum, Michael; Moriarty, Dylan; ...

2017-07-07

Water utilities are vulnerable to a wide variety of human-caused and natural disasters. The Water Network Tool for Resilience (WNTR) is a new open source PythonTM package designed to help water utilities investigate resilience of water distribution systems to hazards and evaluate resilience-enhancing actions. In this paper, the WNTR modeling framework is presented and a case study is described that uses WNTR to simulate the effects of an earthquake on a water distribution system. The case study illustrates that the severity of damage is not only a function of system integrity and earthquake magnitude, but also of the available resourcesmore » and repair strategies used to return the system to normal operating conditions. While earthquakes are particularly concerning since buried water distribution pipelines are highly susceptible to damage, the software framework can be applied to other types of hazards, including power outages and contamination incidents.« less

A software framework for assessing the resilience of drinking water systems to disasters with an example earthquake case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klise, Katherine A.; Bynum, Michael; Moriarty, Dylan

Water utilities are vulnerable to a wide variety of human-caused and natural disasters. The Water Network Tool for Resilience (WNTR) is a new open source PythonTM package designed to help water utilities investigate resilience of water distribution systems to hazards and evaluate resilience-enhancing actions. In this paper, the WNTR modeling framework is presented and a case study is described that uses WNTR to simulate the effects of an earthquake on a water distribution system. The case study illustrates that the severity of damage is not only a function of system integrity and earthquake magnitude, but also of the available resourcesmore » and repair strategies used to return the system to normal operating conditions. While earthquakes are particularly concerning since buried water distribution pipelines are highly susceptible to damage, the software framework can be applied to other types of hazards, including power outages and contamination incidents.« less

The influence of natural deep eutectic solvents on bioactive natural products: studying interactions between a hydrogel model and Schisandra chinensis metabolites.

PubMed

Liu, Yang; Zhang, Yu; Chen, Shao-Nong; Friesen, J Brent; Nikolić, Dejan; Choules, Mary P; McAlpine, James B; Lankin, David C; Gemeinhart, Richard A; Pauli, Guido F

2018-06-01

Natural Deep Eutectic Solvent (NADES) species can exhibit unexpected solubilizing power for lipophilic molecules despite their simple composition: hydrophilic organic molecules and water. In the present study, the unique properties of NADES species were applied in combination with a model polymer system: a hydrophilic chitosan/alginate hydrogel. Briefly, NADES species (e.g., mannose-dimethylurea-water, 2:5:5, mole/mole) formed matrices to 1) dissolve lipophilic molecules (e.g., curcumin), 2) load lipophilic molecule(s) into the hydrogel, and 3) spontaneously vacate from the system. NADES species ubiquitously occur in natural sources, and a crude extract is a mixture of the NADES species and bioactive metabolites. Based on these ideas, we hypothesized that the crude extract may also allow the loading of natural bioactive molecules from a natural NADES species into (bio)hydrogel systems. To evaluate this hypothesis in vitro, Schisandra chinensis fruit extract was chosen as a representative mixture of lipophilic botanical molecules and hydrophilic NADES species. The results showed that the NADES matrix of S. chinensis was capable of loading at least three bioactive lignans (i.e., gomisin A, gomisin J, and angeloylgomisin H) into the polymer system. The lipophilic metabolites can subsequently be released from the hydrogel. The outcomes suggest that a unique drug delivery mechanism may exist in nature, thereby potentially improving the bioavailability of lipophilic metabolites through physicochemical interactions with the NADES. Copyright © 2018 Elsevier B.V. All rights reserved.

Leaching of pesticides from biobeds: effect of biobed depth and water loading.

PubMed

Fogg, Paul; Boxall, Alistair B A; Walker, Allan; Jukes, Andrew

2004-10-06

Pesticides may be released to farmyard surfaces as a result of spillages, leakages, and the decontamination of tractors and sprayers. Biobeds can be used to intercept and treat contaminated runoff, thus minimizing losses to the environment. Previous studies using lined and unlined biobeds showed that water management was the limiting factor for both systems. While lined biobeds effectively retained pesticides, the system rapidly became water logged and degradation was slow. Studies using unlined biobeds showed that >99% of the applied pesticides were removed by the system, with a significant proportion degraded within 9 months. However, peak concentrations of certain pesticides (Koc < 125) were unacceptable to the regulatory authorities. These experiments were designed to optimize the design and management of unlined biobeds. Experiments performed to investigate the relationship between biobed depth and water loading showed that biobeds need to have a minimum depth of 1-1.5 m. The surface area dimension of the biobed depends on the water loading, which is controlled by the nature and frequency of pesticide handling activities on the farm. Leaching losses of all but the most mobile (Koc < 15) pesticides were <0.32% of the applied dose from 1.5 m deep biobeds subject to a water loading of 1175 L m(-2). These were reduced to <0.06% when a water loading of 688 L m(-2) was applied and down to <0.0001% for a water loading of 202 L m(-2). On the basis of these data, a 1.5 m deep biobed, subject to a maximum water loading of 1121 L m(-2) and with a surface area of 40 m(2) should be able to treat < or =44000 L of pesticide waste and washings such that the average concentration of all pesticides, other than those classified as very mobile, does not exceed 5 microg L(-1). This level of treatment can be improved by further reduction in the hydraulic loading.

Influence of enrichment broths on multiplex PCR detection of total coliform bacteria, Escherichia coli and Clostridium perfringens, in spiked water samples.

PubMed

Worakhunpiset, S; Tharnpoophasiam, P

2009-07-01

Although multiplex PCR amplification condition for simultaneous detection of total coliform bacteria, Escherichia coli and Clostridium perfringens in water sample has been developed, results with high sensitivity are obtained when amplifying purified DNA, but the sensitivity is low when applied to spiked water samples. An enrichment broth culture prior PCR analysis increases sensitivity of the test but the specific nature of enrichment broth can affect the PCR results. Three enrichment broths, lactose broth, reinforced clostridial medium and fluid thioglycollate broth, were compared for their influence on sensitivity and on time required with multiplex PCR assay. Fluid thioglycollate broth was the most effective with shortest enrichment time and lowest detection limit.

Carbon and water footprints of irrigated corn and non-irrigated wheat in Northeast Spain.

PubMed

Abrahão, Raphael; Carvalho, Monica; Causapé, Jesús

2017-02-01

Irrigation increases yields and allows several crops to be produced in regions where it would be naturally impossible due to limited rainfall. However, irrigation can cause several negative environmental impacts, and it is important to understand these in depth for the correct application of mitigation measures. The life cycle assessment methodology was applied herein to compare the main irrigated and non-irrigated crops in Northeast Spain (corn and wheat, respectively), identifying those processes with greater contribution to environmental impacts (carbon and water footprint categories) and providing scientifically-sound information to facilitate government decisions. Due to concerns about climate change and water availability, the methods selected for evaluation of environmental impacts were IPCC 2013 GWP (carbon footprint) and water scarcity indicator (water footprint). The area studied, a 7.38-km 2 basin, was monitored for 12 years, including the period before, during, and after the implementation of irrigation. The functional unit, to which all material and energy flows were associated with, was the cultivation of 1 ha, throughout 1 year. The overall carbon footprint for irrigated corn was higher, but when considering the higher productivity achieved with irrigation, the emissions per kilogram of corn decrease and finally favor this irrigated crop. When considering the water footprint, the volumes of irrigation water applied were so high that productivity could not compensate for the negative impacts associated with water use in the case of corn. Nevertheless, consideration of productivities and gross incomes brings the results closer. Fertilizer use (carbon footprint) and irrigation water (water footprint) were the main contributors to the negative impacts detected.

A new twist to a traditional approach to environmental monitoring: differentiation of oil sands process-affected waters and natural systems by comparison of individual organic acids

NASA Astrophysics Data System (ADS)

Scarlett, A.; Lengger, S.; West, C.; Rowland, S.

2013-12-01

Review panels of both the Canadian Federal and Alberta Provincial governments have recommended a complete overhaul of existing monitoring programs of the Athabasca oil sands industry and have called for a greater understanding of the potential impacts of mining activities to allow for future sustainable development. Due to the no release policy, it is critical that leakages of oil sands process-affected waters (OSPW) from tailings ponds can be differentiated from natural waters flowing through the McMurray formation into the Athabasca river system. Environmental monitoring of oil contamination usually entails profiling of known compounds, e.g. the US EPA list of priority Polycyclic Aromatic Hydrocarbons, but until now a similar approach has not been possible for OSPW due to its extreme complexity. It has been estimated that the number of carboxylic acids, historically referred to as ';naphthenic acids' (NA) in OSPW, to be in excess of 10000 compounds. Until recently, individual structures of these NA were unknown but analyses by tandem gas chromatography mass spectrometry (GCxGC-MS) have now begun to reveal the individual structures of alicyclic, aromatic and sulphur-containing acids within OSPWs stored in tailings ponds. Now that some individual structures present in OSPW are known and standards are available, a methodological approach similar to traditional oil monitoring can be developed using individual diamondoid NA and recently discovered diacids and applied to tailings pond OSPW and environmental waters. One obstacle to understanding whether the NA present in environmental groundwater samples are associated with particular tailings ponds is the lack of knowledge of the variability of OSPW within and between ponds. In the current study, GCxGC-MS analyses have been applied to statistically compare OSPWs of two industries, both temporally and spatially, using specific, known compounds as well as associated isomers. Although variation within individual ponds was observed, there was a significant difference (P < 0.05) between the ponds of the two industries. Having determined the variability in the ponds, further statistical analysis was applied to compare ratios of individual NAs in the ponds with those in groundwaters, near and distant from the ponds, thereby providing a measure of the probability that a particular groundwater sample is associated with a specific tailings pond. We have previously shown that the ability to identify individual chemical structures within these highly complex samples facilitates relevant toxicological testing and modelling. Here, we show it to be of crucial importance for differentiating tailings ponds and natural groundwaters and thus provides a relatively simple and robust means of monitoring anthropogenic impacts on natural systems arising from oil sands mining activities.

Computational Intelligence-Assisted Understanding of Nature-Inspired Superhydrophobic Behavior.

PubMed

Zhang, Xia; Ding, Bei; Cheng, Ran; Dixon, Sebastian C; Lu, Yao

2018-01-01

In recent years, state-of-the-art computational modeling of physical and chemical systems has shown itself to be an invaluable resource in the prediction of the properties and behavior of functional materials. However, construction of a useful computational model for novel systems in both academic and industrial contexts often requires a great depth of physicochemical theory and/or a wealth of empirical data, and a shortage in the availability of either frustrates the modeling process. In this work, computational intelligence is instead used, including artificial neural networks and evolutionary computation, to enhance our understanding of nature-inspired superhydrophobic behavior. The relationships between experimental parameters (water droplet volume, weight percentage of nanoparticles used in the synthesis of the polymer composite, and distance separating the superhydrophobic surface and the pendant water droplet in adhesive force measurements) and multiple objectives (water droplet contact angle, sliding angle, and adhesive force) are built and weighted. The obtained optimal parameters are consistent with the experimental observations. This new approach to materials modeling has great potential to be applied more generally to aid design, fabrication, and optimization for myriad functional materials.

Evaluating Groundwater-Surface Water Exchange With A New Point Measurement Device

NASA Astrophysics Data System (ADS)

Cremeans, M.; Devlin, J. F.; McKnight, U. S.; Bjerg, P. L.; Nairn, R.

2017-12-01

Estimating exchange at the groundwater-surface water interface (GWSWI) could be crucial to designing effective remediation measures. The StreamBed Point Velocity Probe (SBPVP), a new point measurement device, measures in situ groundwater velocities at the GWSWI without reliance on estimations of hydraulic conductivity, porosity, or gradient information. The SBPVP has been applied to natural and engineered interfaces at contaminated sites, a stream and vertical flow bioreactor, respectively. Velocity data ( 18 cm/day to 2600 cm/day in the stream, and 54 cm/day to 161 cm/day in the bioreactor) were used to determine water and solute fluxes (as well as potential contaminant attenuation rates) at these sites. Analysis of the spatial distribution of velocity values in a streambed illustrated the extremely heterogeneous nature of that environment, while the engineered system was found to be relatively homogeneous by comparison. Combining SBPVP velocity data with geochemical data supports the calculation of mass discharges and mass removal rates. The wide range of exchange rate variability (within and between these sites) suggests that detailed characterization of the GWSWI interface is useful information for remediation in both cases.

Sinkhole risk assessment by ERT: The case study of Sirino Lake (Basilicata, Italy)

NASA Astrophysics Data System (ADS)

Giampaolo, V.; Capozzoli, L.; Grimaldi, S.; Rizzo, E.

2016-01-01

The presence of natural or artificial lakes and reservoirs that can drain because of natural phenomena can generate catastrophic events affecting urban and agricultural areas next to the source area. Therefore, geophysical prospecting techniques have been applied in the study of Sirino Lake, which, during the last century, was affected by the sudden opening of small sinkholes, resulting in the almost total draining of the lake and in the sudden increase of water flow rates of distal springs. Two electrical resistivity tomographies (ERTs) were carried out across the lake, using electrode arrays located on land and across the water body. Self-potential (SP) data were acquired around the lake shore and the surrounding area. The geophysical prospecting contributed significant data toward explaining the unique hydrogeological characteristics of the lake. Integration of geophysical, geological, hydrogeological, and geomorphological data allowed us to estimate the thickness of the lacustrine deposits beneath the lake, to describe the main patterns of the subsurface fluid flows in the area, and to identify possible water escape routes causing the piping phenomena.

Occurrence of Pseudomonas aeruginosa in waters: implications for patients with cystic fibrosis (CF).

PubMed

Caskey, S; Stirling, J; Moore, J E; Rendall, J C

2018-06-01

Chronic Pseudomonas aeruginosa infection is associated with increased morbidity and mortality in patients with cystic fibrosis (CF). Current understanding of risk factors for acquisition is limited and so the aim of this study was to examine a large sample of environmental waters from diverse sources. Environmental water samples (n = 7904) from jacuzzis, hydrants, swimming pools, hot tubs, plunge pools, bottled natural mineral water, taps, springs, ice machines, water coolers, bores and showers were examined for the presence of P. aeruginosa. Pseudomonas aeruginosa was detected in 524/7904 (6·6%) waters examined. Hot tubs (51/243; 20·9%), tap water (3/40; 8%) and jacuzzis (432/5811; 7·4%) were the most likely environments where P. aeruginosa was isolated. Pseudomonas aeruginosa was isolated from bottled water (2/67; 3%). Our study highlights the ubiquitous nature of P. aeruginosa in the environment. Given CF patients are frequently counselled to make lifestyle changes to minimize P. aeruginosa exposure, these results have important implications. In particular, the occurrence of P. aeruginosa in tap water highlights the need to disinfect the CF patients' nebulizer after each use. This study examined a large number of water sources (n = 7904) over a 9-year period for the presence of Pseudomonas aeruginosa. The study highlighted that jacuzzis (n = 5811; 7% positive) and hot tubs had the highest occurrence of this organism (n = 243, 21% positive). Patients with cystic fibrosis (CF) are interested in knowing what water environments are likely to be contaminated with this organism, as this bacterium is an important cause of increased morbidity and mortality in such patients. With such information, CF patients and parents may make informed decisions about lifestyle choice and water environment avoidance. © 2018 The Society for Applied Microbiology.

Water-saving interventions assessment framework: an application for the Urmia Lake Restoration Program

NASA Astrophysics Data System (ADS)

Shadkam, Somayeh; Oel, Pieter; Kabat, Pavel; Ludwig, Fulco

2017-04-01

Increasing water demand often results in unsustainable water use leaving insufficient amounts of water for sustaining natural environments. Therefore, to save natural resources water-saving interventions have been introduced to the environmental policy agenda in many (semi)-arid regions. Many policies, however, have failed reaching their objectives to increase water availability for the environment. This calls for a comprehensive tool to assess water-saving policies. Therefore, this study introduces a constructive framework to assess the policies by estimating five components: 1) Total water demand under socio-economic scenarios, 2) Water supply under climate change scenarios, 3) Water withdrawal for different sectors, 4) Water depletion and 5) Environmental flow. The framework, was applied to assess Urmia Lake Restoration Program (ULRP), which aims to restore the drying Urmia Lake in north-western Iran by increasing the lake inflow by 3.1×106m3yr-1. Results suggest that although the ULRP helps to increase inflow by up to 57% it is unlikely to fully reach its target. The analysis shows that there are three main reasons for the potential poor performance. The first reason is decreasing return flows due to increasing irrigation efficiency. This means that the expected increase in lake inflow volume is smaller than the volume saved by increasing irrigation efficiency. The second reason is increased depletion which is due to neglecting the fact that agricultural water demand is currently higher than available water for agriculture. As a result, increasing water use efficiency may result in increased water depletion. The third reason is ignoring the potential impact of climate change, which might decrease future water availability by 3% to 15%. Our analysis suggests that to reach the intervention target, measures need to focus on reducing Water demand and Water depletion rather than on reducing Water withdrawals. The assessment framework can be used to comprehensively assess water-saving intervention plans, particularly in water-stressed basins.

Project AProWa: a national view on managing trade-offs between agricultural production and conservation of aquatic ecosystems

NASA Astrophysics Data System (ADS)

Dietzel, Anne; Rahn, Eric; Stamm, Christian

2014-05-01

Swiss agriculture is legally committed to fulfill several, partially conflicting goals such as agricultural production on the one hand and the conservation of natural resources on the other hand. In the context of the research project AProWa ("Agricultural Production and Water"), the relationships between the production aspect and the conservation of aquatic ecosystems is analyzed with a holistic approach. Agricultural production and the protection of water resources have high potential for conflicts: Farmers use ground and surface water to irrigate their fields. On the other hand, drainage systems enable the production on otherwise unfavorably wet soils. These in turn often affect ground water recharge and divert precipitation directly into surface waters, which changes their hydrological regime. Typically, drainage systems also elevate the input of nutrients and pesticides into the water bodies. In general, applied fertilizers, plant protection products, veterinary drugs and phytohormones of cultivated plants are introduced into the ground and surface waters through different processes such as drift, leaching, runoff, preferential flow or erosion. They influence the nutrient cycles and ecological health of aquatic systems. The nutrient and pesticide loss processes themselves can be altered by tillage operations and other agricultural practices. Furthermore, the competition for space can lead to additional conflicts between agriculture and the protection of aquatic ecosystems. For example, channelized or otherwise morphologically changed rivers do not have a natural discharge pattern and are often not suitable for the local flora and fauna; but naturally meandering rivers need space that cannot be used for agriculture. In a highly industrialized and densely populated country like Switzerland, all these potential conflicts are of importance. Although it is typically seen as a water-rich country, local and seasonal overexploitation of rivers through water extraction for irrigation can already be documented. Due to drier summers induced by climate change, this phenomenon is expected to gain more importance in the future. Related to water quantity and quality it is crucial to think about the diverging interests between the supply of the population with national agricultural products and the preservation of the water bodies, their ecological value and their other ecosystem services (e.g. drinking water supply). The project AProWa attempts to elucidate trade-offs of national goals for water protection and agricultural production in Switzerland by involving stakeholders from agricultural administration (Federal Office for Agriculture, FOAG), agricultural research (Agroscope), water research (Swiss Federal Institute of Aquatic Science and Technology, Eawag) and environmental protection (Federal Office for the Environment, FOEN). This is done by applying multi-criteria decision analysis facilitating consensus regarding goals and possible activities and alternatives to reach these goals. This is followed by an evaluation of main conflicts and prioritized research gaps. We present preliminary results from workshops and interdisciplinary discussion groups that encompass an objectives hierarchy reflecting agricultural production and water conservation goals. Furthermore, an inventory of agricultural practices and water protection measures is presented, enabling their evaluation for the provision of agricultural production while sustaining aquatic ecosystems.

Spectral analysis of the Forel-Ule Ocean colour comparator scale

NASA Astrophysics Data System (ADS)

Wernand, M. R.; van der Woerd, H. J.

2010-04-01

François Alphonse Forel (1890) and Willi Ule (1892) composed a colour comparator scale, with tints varying from indigo-blue to coca-cola brown, to quantify the colour of natural waters, like seas, lakes and rivers. For each measurement, the observer compares the colour of the water above a submersed white disc (Secchi disc) with the hand-held scale of pre-defined colours. The scale can be well reproduced from a simple recipe for twenty-one coloured chemical solutions and because the ease of its use, the Forel-Ule (FU) scale has been applied globally and intensively by oceanographers and limnologists from the year 1890. Indeed, the archived FU data belong to the oldest oceanographic data sets and do contain information on the changes in geobiophysical properties of natural waters during the last century. In this article we describe the optical properties of the FU-scale and its ability to cover the colours of natural waters, as observed by the human eye. The recipe of the scale and its reproduction is described. The spectral transmission of the tubes, with belonging chromaticity coordinates, is presented. The FU scale, in all its simplicity, is found to be an adequate ocean colour comparator scale. The scale is well characterized, is stable and observations are reproducible. This supports the idea that the large historic data base of FU measurements is coherent and well calibrated. Moreover, the scale can be coupled to contemporary multi-spectral observations with hand-held and satellite-based spectrometers.

Ecohydrology of Graciosa semi-natural grasslands: water use and evapotranspiration partition

NASA Astrophysics Data System (ADS)

Paço, Teresa A.; Paredes, Paula; Azevedo, Eduardo B.; Madruga, João S.; Pereira, Luís S.

2016-04-01

Semi-natural grasslands are a main landscape of Graciosa and other Islands of Azores. The present study aims at calibrate and validate the soil water balance model SIMDualKc for those grasslands aiming at assessing the dynamics of soil water and evapotranspiration. This objective relates with the need to improve knowledge on the ecohydrology of grasslands established in (volcanic) Andosols. This model adopts the dual crop coefficient approach to compute daily crop evapotranspiration (ETc) and to perform its partition into transpiration (T) and soil evaporation (Es). The application refers to a semi-natural grassland sporadically sowed with ryegrass (Lolium multiflorum Lam.). Model calibration and validation were performed comparing simulated against observed grassland evapotranspiration throughout two periods in consecutive years. Daily ET values were derived from eddy covariance data collected at the Eastern North Atlantic (ENA) facility of the ARM programme (established and supported by the U.S. Department of Energy with the collaboration of the local government and University of the Azores), at Graciosa, Azores (Portugal). Various statistical performance indicators were used to assess model accuracy and results show a good adequacy of the model for predicting vegetation ET in such conditions. Surface flux energy balance was also evaluated throughout the observation period (2014-2016). The ratio Es/ET shows that soil evaporation is much small than T/ET due to high soil cover by vegetation. The model was then applied to contrasting climatic conditions (dry vs. wet years) to assess related impacts on water balance components and grassland transpiration.

Mass transfer and carbon isotope evolution in natural water systems

USGS Publications Warehouse

Wigley, T.M.L.; Plummer, Niel; Pearson, F.J.

1978-01-01

This paper presents a theoretical treatment of the evolution of the carbon isotopes C13 and C14 in natural waters and in precipitates which derive from such waters. The effects of an arbitrary number of sources (such as dissolution of carbonate minerals and oxidation of organic material) and sinks (such as mineral precipitation, CO2 degassing and production of methane), and of equilibrium fractionation between solid, gas and aqueous phases are considered. The results are expressed as equations relating changes in isotopic composition to changes in conventional carbonate chemistry. One implication of the equations is that the isotopic composition of an aqueous phase may approach a limiting value whenever there are simultaneous inputs and outputs of carbonate. In order to unambiguously interpret isotopic data from carbonate precipitates and identify reactants and products in reacting natural waters, it is essential that isotopic changes are determined chiefly by reactant and product stoichiometry, independent of reaction path. We demonstrate that this is so by means of quantitative examples. The evolution equations are applied to: 1. (1) carbon-14 dating of groundwaters; 2. (2) interpretation of the isotopic composition of carbonate precipitates, carbonate cements and diagenetically altered carbonates; and 3. (3) the identification of chemical reaction stoichiometry. These applications are illustrated by examples which show the variation of ??C13 in solutions and in precipitates formed under a variety of conditions involving incongruent dissolution, CO2 degassing, methane production and mineral precipitation. ?? 1978.

Space-assisted irrigation management: an operational perspective

NASA Astrophysics Data System (ADS)

Calera Belmonte, Alfonso; Jochum, Anne M.; Cuesta Garcia, Andres

2004-10-01

Irrigation Advisory Services (IAS) are the natural management instruments to achieve a better efficiency in the use of water for irrigation. IAS help farmers to apply water according to the actual crop water requirements and thus, to optimize production and cost-effectiveness. The project DEMETER (DEMonstration of Earth observation TEchnologies in Routine irrigation advisory services) aims at assessing and demonstrating how the performance and cost-effectiveness of IAS is substantially improved by the incorporation of Earth observation (EO) techniques and Information Society Technology (IT) into their day-to-day operations. EO allows for efficiently monitoring crop water requirements of each field in extended areas. The incorporation of IT in the generation and distribution of information makes that information easily available to IAS and to its associated farmers (the end-users) in a personalized way. This paper describes the methodology and selected results.

Impact of compost, vermicompost and biochar on soil fertility, maize yield and soil erosion in Northern Vietnam: a three year mesocosm experiment.

PubMed

Doan, Thuy Thu; Henry-des-Tureaux, Thierry; Rumpel, Cornelia; Janeau, Jean-Louis; Jouquet, Pascal

2015-05-01

Compost, vermicompost and biochar amendments are thought to improve soil quality and plant yield. However, little is known about their long-term impact on crop yield and the environment in tropical agro-ecosystems. In this study we investigated the effect of organic amendments (buffalo manure, compost and vermicompost) and biochar (applied alone or with vermicompost) on plant yield, soil fertility, soil erosion and water dynamics in a degraded Acrisol in Vietnam. Maize growth and yield, as well as weed growth, were examined for three years in terrestrial mesocosms under natural rainfall. Maize yield and growth showed high inter-annual variability depending on the organic amendment. Vermicompost improved maize growth and yield but its effect was rather small and was only significant when water availability was limited (year 2). This suggests that vermicompost could be a promising substrate for improving the resistance of agrosystems to water stress. When the vermicompost-biochar mixture was applied, further growth and yield improvements were recorded in some cases. When applied alone, biochar had a positive influence on maize yield and growth, thus confirming its interest for improving long-term soil productivity. All organic amendments reduced water runoff, soil detachment and NH₄(+) and NO₃(-) transfer to water. These effects were more significant with vermicompost than with buffalo manure and compost, highlighting that the beneficial influence of vermicompost is not limited to its influence on plant yield. In addition, this study showed for the first time that the combination of vermicompost and biochar may not only improve plant productivity but also reduce the negative impact of agriculture on water quality. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessing the ecological effects of water stress and pollution in a temporary river - Implications for water management.

PubMed

Karaouzas, Ioannis; Smeti, Evangelia; Vourka, Aikaterini; Vardakas, Leonidas; Mentzafou, Aggeliki; Tornés, Elisabet; Sabater, Sergi; Muñoz, Isabel; Skoulikidis, Nikolaos Th; Kalogianni, Eleni

2018-03-15

Temporary rivers are dynamic and complex ecosystems that are widespread in arid and semi-arid regions, such as the Mediterranean. Biotic communities adapted in their intermittent nature could withstand recurrent drought events. However, anthropogenic disturbances in the form of water stress and chemical pollution challenge biota with unpredictable outcomes, especially in view of climate change. In this study we assess the response of the biotic community of a temporary river to environmental stressors, focusing on water stress and pollution. Towards this aim, several metrics of four biotic groups (diatoms, macrophytes, macroinvertebrates and fish) were applied. All biotic groups responded to a pollution gradient mainly driven by land use, distinct functional groups of all biota responded to water stress (a response related to the rheophilic nature of the species and their resistance to shear stress), while the combined effects of water stress and pollution were apparent in fish. Biotic groups presented a differential temporal response to water stress, where diatom temporal assemblage patterns were explained by water stress variables of short-time response (15days), while the responses of the other biota were associated to longer time periods. There were two time periods of fish response, a short (15days) and a long-time response (60-75days). When considering management decisions, our results indicate that, given the known response of river biota to pollution, biomonitoring of temporary rivers should also involve metrics that can be utilized as early warnings of water stress. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment of forestry best management practices II: patterns in stream biological endpoints in terms of natural variability and fertilization

Treesearch

Camille Flinders; Daniel L. McLaughlin; Larry Korhnak; William J. Arthurs; Joan Ikoma; Matthew J. Cohen; Erik B. Schilling

2016-01-01

Watersheds dominated by forest cover typically have high quality water. In managed forests, fertilizers may be periodically applied during the growing period. The Florida Forest Service has developed Best Management Practices (BMPs) for managed forests to minimize the potential impacts of forestry operations, including fertilization, to forest streams and maintain ...

Solar heating and cooling.

PubMed

Duffie, J A

1976-01-01

Solar energy is discussed as an energy resource that can be converted into useful energy forms to meet a variety of energy needs. The review briefly explains the nature of this energy resource, the kinds of applications that can be made useful, and the status of several systems to which it has been applied. More specifically, information on solar collectors, solar water heating, solar heating of buildings, solar cooling plus other applications, are included.

Permeability recovery of damaged water sensitive core using ultrasonic waves.

PubMed

Khan, Nasir; Pu, Chunsheng; Li, Xu; He, Yanlong; Zhang, Lei; Jing, Cheng

2017-09-01

It is imperative to recover the well productivity lose due to formation damage nearby wellbore during variant well operations. Some indispensable issues in conventional techniques make ultrasonic technology more attractive due to simple, reliable, favorable, cost-effective, and environment friendly nature. This study proposes the independent and combined use of ultrasonic waves and chemical agents for the treatment of already damaged core samples caused by exposure to distilled water. Results elucidate that ultrasonic waves with optimum (20kHz, 1000W) instead of maximum frequency and power worked well in the recovery owing to peristaltic transport caused by matching of natural frequency with acoustic waves frequency. In addition, hundred minutes was investigated as optimum irradiation time which provided ample time span to detach fine loosely suspended particles. However, further irradiation adversely affected the damaged permeability recovery. Moreover, permeability improvement attributes to cavitation due to ultrasonic waves propagation through fluid contained in porous medium and thermal energy generated by three different ways. Eventually, experimental outcomes indicated that maximum (25.3%) damaged permeability recovery was witnessed by applying ultrasonic waves with transducer #2 (20kHz and 1000W) and optimum irradiation timeframe (100min). This recovery was further increased to 45.8% by applying chemical agent and optimum ultrasonic waves simultaneously. Copyright © 2017 Elsevier B.V. All rights reserved.

A Solar Radiation Parameterization for Atmospheric Studies. Volume 15

NASA Technical Reports Server (NTRS)

Chou, Ming-Dah; Suarez, Max J. (Editor)

1999-01-01

The solar radiation parameterization (CLIRAD-SW) developed at the Goddard Climate and Radiation Branch for application to atmospheric models are described. It includes the absorption by water vapor, O3, O2, CO2, clouds, and aerosols and the scattering by clouds, aerosols, and gases. Depending upon the nature of absorption, different approaches are applied to different absorbers. In the ultraviolet and visible regions, the spectrum is divided into 8 bands, and single O3 absorption coefficient and Rayleigh scattering coefficient are used for each band. In the infrared, the spectrum is divided into 3 bands, and the k-distribution method is applied for water vapor absorption. The flux reduction due to O2 is derived from a simple function, while the flux reduction due to CO2 is derived from precomputed tables. Cloud single-scattering properties are parameterized, separately for liquid drops and ice, as functions of water amount and effective particle size. A maximum-random approximation is adopted for the overlapping of clouds at different heights. Fluxes are computed using the Delta-Eddington approximation.

Advanced mortar coatings for cultural heritage protection. Durability towards prolonged UV and outdoor exposure.

PubMed

Pino, F; Fermo, P; La Russa, M; Ruffolo, S; Comite, V; Baghdachi, J; Pecchioni, E; Fratini, F; Cappelletti, G

2017-05-01

In the present work, two kinds of hybrid polymeric-inorganic coatings containing TiO 2 or SiO 2 particles and prepared starting from two commercial resins (Alpha®SI30 and Bluesil®BP9710) were developed and applied to two kinds of mortars (an air-hardening calcic lime mortar [ALM] and a natural hydraulic lime mortar [HLM]) to achieve better performances in terms of water repellence and consequently damage resistance. The two pure commercial resins were also applied for comparison purposes. Properties of the coated materials and their performance were studied using different techniques such as contact angle measurements, capillary absorption test, mercury intrusion porosimetry, surface free energy, colorimetric measurements and water vapour permeability tests. Tests were also performed to determine the weathering effects on both the commercial and the hybrid coatings in order to study their durability. Thus, exposures to UV radiation, to UV radiation/condensed water cycles and to a real polluted atmospheric environment have been performed. The effectiveness of the hybrid SiO 2 based coating was demonstrated, especially in the case of the HLM mortar.

The influence of geology and land use on arsenic in stream sediments and ground waters in New England, USA

USGS Publications Warehouse

Robinson, G.R.; Ayotte, J.D.

2006-01-01

Population statistics for As concentrations in rocks, sediments and ground water differ by geology and land use features in the New England region, USA. Significant sources of As in the surficial environment include both natural weathering of rocks and anthropogenic sources such as arsenical pesticides that were commonly applied to apple, blueberry and potato crops during the first half of the 20th century in the region. The variation of As in bedrock ground water wells has a strong positive correlation with geologic features at the geologic province, lithology group, and bedrock map unit levels. The variation of As in bedrock ground water wells also has a positive correlation with elevated stream sediment and rock As chemistry. Elevated As concentrations in bedrock wells do not correlate with past agricultural areas that used arsenical pesticides on crops. Stream sediments, which integrate both natural and anthropogenic sources, have a strong positive correlation of As concentrations with rock chemistry, geologic provinces and ground water chemistry, and a weaker positive correlation with past agricultural land use. Although correlation is not sufficient to demonstrate cause-and-effect, the statistics favor rock-based As as the dominant regional source of the element in stream sediments and ground water in New England. The distribution of bedrock geology features at the geologic province, lithology group and map unit level closely correlate with areas of elevated As in ground water, stream sediments, and rocks. ?? 2006 Elsevier Ltd. All rights reserved.

Incorporating agricultural management into an earth system model for the Pacific Northwest region: Interactions between climate, hydrology, agriculture, and economics

NASA Astrophysics Data System (ADS)

Chinnayakanahalli, K.; Adam, J. C.; Stockle, C.; Nelson, R.; Brady, M.; Rajagopalan, K.; Barber, M. E.; Dinesh, S.; Malek, K.; Yorgey, G.; Kruger, C.; Marsh, T.; Yoder, J.

2011-12-01

For better management and decision making in the face of climate change, earth system models must explicitly account for natural resource and agricultural management activities. Including crop system, water management, and economic models into an earth system modeling framework can help in answering questions related to the impacts of climate change on irrigation water and crop productivity, how agricultural producers can adapt to anticipated climate change, and how agricultural practices can mitigate climate change. Herein we describe the coupling of the Variability Infiltration Capacity (VIC) land surface model, which solves the water and energy balances of the hydrologic cycle at regional scales, with a crop-growth model, CropSyst. This new model, VIC-CropSyst, is the land surface model that will be used in a new regional-scale model development project focused on the Pacific Northwest, termed BioEarth. Here we describe the VIC-CropSyst coupling process and its application over the Columbia River basin (CRB) using agricultural-specific land cover information. The Washington State Department of Agriculture (WSDA) and U. S. Department of Agriculture (USDA) cropland data layers were used to identify agricultural land use patterns, in which both irrigated and dry land crops were simulated. The VIC-CropSyst model was applied over the CRB for the historical period of 1976 - 2006 to establish a baseline for surface water availability, irrigation demand, and crop production. The model was then applied under future (2030s) climate change scenarios derived from statistically-downscaled Global Circulation Models output under two emission scenarios (A1B and B1). Differences between simulated future and historical irrigation demand, irrigation water availability, and crop production were used in an economics model to identify the most economically-viable future cropping pattern. The economics model was run under varying scenarios of regional growth, trade, water pricing, and water capacity providing a spectrum of possible future cropping patterns. The resulting cropping patterns were then used in VIC-CropSyst to quantify the impacts of climate change, economic, and water management scenarios on crop production, and water resources availability. This modeling framework provides opportunities to study the interactions between human activities and complex natural processes and is a valuable tool for inclusion in an earth system model with the goal of informing land use and water management.

Aqueduct: an interactive tool to empower global water risk assessment

NASA Astrophysics Data System (ADS)

Reig, Paul; Gassert, Francis

2013-04-01

The Aqueduct Water Risk Atlas (Aqueduct) is a publicly available, global database and interactive tool that maps indicators of water related risks for decision makers worldwide. Aqueduct makes use of the latest geo-statistical modeling techniques to compute a composite index and translate the most recently available hydrological data into practical information on water related risks for companies, investors, and governments alike. Twelve global indicators are grouped into a Water Risk Framework designed in response to the growing concerns from private sector actors around water scarcity, water quality, climate change, and increasing demand for freshwater. The Aqueduct framework includes indicators of water stress, variability in supply, storage, flood, drought, groundwater, water quality and social conflict, addressing both spatial and temporal variation in water hazards. It organizes indicators into three categories of risk that bring together multiple dimensions of water related risk into comprehensive aggregated scores, which allow for dynamic weighting to capture users' unique exposure to water hazards. All information is compiled into an online, open access platform, from which decision-makers can view indicators, scores, and maps, conduct global risk assessments, and export data and shape files for further analysis. Companies can use this tool to evaluate their exposure to water risks across operations and supply chains, investors to assess water-related risks in their portfolio, and public-sector actors to better understand water security. Additionally, the open nature of the data and maps allow other organizations to build off of this effort with new research, for example in the areas of water-energy or water-food relationships. This presentation will showcase the Aqueduct Water Risk Atlas online tool and the features and functionalities it offers, as well as explain how it can be used for both private and public sector applications. The session will feature a live demonstration of how the tool can be applied to evaluate exposure to water-related risks worldwide and drive change on the ground by prioritizing areas for investment to increase resilience to natural hazards.

Urban water infrastructure asset management - a structured approach in four water utilities.

PubMed

Cardoso, M A; Silva, M Santos; Coelho, S T; Almeida, M C; Covas, D I C

2012-01-01

Water services are a strategic sector of large social and economic relevance. It is therefore essential that they are managed rationally and efficiently. Advanced water supply and wastewater infrastructure asset management (IAM) is key in achieving adequate levels of service in the future, particularly with regard to reliable and high quality drinking water supply, prevention of urban flooding, efficient use of natural resources and prevention of pollution. This paper presents a methodology for supporting the development of urban water IAM, developed during the AWARE-P project as well as an appraisal of its implementation in four water utilities. Both water supply and wastewater systems were considered. Due to the different contexts and features of the utilities, the main concerns vary from case to case; some problems essentially are related to performance, others to risk. Cost is a common deciding factor. The paper describes the procedure applied, focusing on the diversity of drivers, constraints, benefits and outcomes. It also points out the main challenges and the results obtained through the implementation of a structured procedure for supporting urban water IAM.

Hindcast of water availability in regional aquifer systems using MODFLOW Farm Process

USGS Publications Warehouse

Schmid, Wolfgang; Hanson, Randall T.; Faunt, Claudia C.; Phillips, Steven P.

2015-01-01

Coupled groundwater and surface-water components of the hydrologic cycle can be simulated by the Farm Process for MODFLOW (MF-FMP) in both irrigated and non-irrigated areas and aquifer-storage and recovery systems. MF-FMP is being applied to three productive agricultural regions of different scale in the State of California, USA, to assess the availability of water and the impacts of alternative management decisions. Hindcast simulations are conducted for similar periods from the 1960s to near recent times. Historical groundwater pumpage is mostly unknown in one region (Central Valley) and is estimated by MF-FMP. In another region (Pajaro Valley), recorded pumpage is used to calibrate model-estimated pumpage. Multiple types of observations are used to estimate uncertain parameters, such as hydraulic, land-use, and farm properties. MF-FMP simulates how climate variability and water-import availability affect water demand and supply. MF-FMP can be used to predict water availability based on anticipated changes in anthropogenic or natural water demands. Keywords groundwater; surface-water; irrigation; water availability; response to climate variability/change

Shading and watering as a tool to mitigate the impacts of climate change in sea turtle nests.

PubMed

Hill, Jacob E; Paladino, Frank V; Spotila, James R; Tomillo, Pilar Santidrián

2015-01-01

Increasing sand temperatures resulting from climate change may negatively impact sea turtle nests by altering sex ratios and decreasing reproductive output. We analyzed the effect of nest shading and watering on sand temperatures as climate mitigation strategies in a beach hatchery at Playa Grande, Costa Rica. We set up plots and placed thermocouples at depths of 45 cm and 75 cm. Half of the plots were shaded and half were exposed to the sun. Within these exposure treatments, we applied three watering treatments over one month, replicating local climatic conditions experienced in this area. We also examined gravimetric water content of sand by collecting sand samples the day before watering began, the day after watering was complete, and one month after completion. Shading had the largest impact on sand temperature, followed by watering and depth. All watering treatments lowered sand temperature, but the effect varied with depth. Temperatures in plots that received water returned to control levels within 10 days after watering stopped. Water content increased at both depths in the two highest water treatments, and 30 days after the end of water application remained higher than plots with low water. While the impacts of watering on sand temperature dissipate rapidly after the end of application, the impacts on water content are much more lasting. Although less effective at lowering sand temperatures than shading, watering may benefit sea turtle clutches by offsetting negative impacts of low levels of rain in particularly dry areas. Prior to implementing such strategies, the natural conditions at the location of interest (e.g. clutch depth, environmental conditions, and beach characteristics) and natural hatchling sex ratios should be taken into consideration. These results provide insight into the effectiveness of nest shading and watering as climate mitigation techniques and illustrate important points of consideration in the crafting of such strategies.

Determine utility of ERTS-1 to detect and monitor area strip mining and reclamation. [southeastern Ohio

NASA Technical Reports Server (NTRS)

Rogers, R. H. (Principal Investigator); Pettyjohn, W. A.

1975-01-01

The author has identified the following significant results. Computer techniques were applied to process ERTS tapes acquired over coal mining operations in southeastern Ohio on 21 August 1972 and 3 September 1973. ERTS products obtained included geometrically correct map overlays showing stripped earth, partially reclaimed earth, water, and natural vegetation. Computer-generated tables listing the area covered by each land-water category in square kilometers and acres were produced. By comparing these mapping products, the study demonstrates the capability of ERTS to monitor changes in the extent of stripping, success of reclamation, and the secondary effects of mining on the environment.

Numerical Methods for Synoptic Computation of Oceanic Fronts and Water Type Boundaries and their Significance in Applied Oceanography

DTIC Science & Technology

1966-06-01

and L. C. Clarke 1965 Clarke, L. C. and R. J. Renard 1966 Dietrich, G. and K . Kalle 1957 Dietrich, G. 1964 Griffiths, R. C. 1965 Hela...8217s n AppA. 1 (sd LiceanGgrapny« (9) T s c h n 1 ’■■- a i. n Q ’z.e , ■: 10) Ci Bf k e , I..... ^ i-’ •■ (10) i...aevastu , i . ill) J u...only between water masses of different salinity but also between those differing in other properties, such as temperature." The nature of the oceanic

Determination of trace arsenic on hanging copper amalgam drop electrode.

PubMed

Piech, Robert; Baś, Bogusław; Niewiara, Ewa; Kubiak, Władysław W

2007-04-30

Hanging copper amalgam drop electrode has been applied for trace determination of arsenic by cathodic stripping analysis. Detection limit for As(III) as low as 0.33nM (0.02mug/L) at deposition time (240s) could be obtained. For seven successive determinations of As(III) at concentration of 5nM relative standard deviation was 2.5% (n=7). Interferences from selected metals and surfactant substances were examined. Absence of copper ions in sample solution causes easier optimization and makes method less vulnerable on contamination. The developed method was validated by analysis of certified reference materials (CRMs) and applied to arsenic determinations in natural water samples.

Numerical study on the influences of Nanliu River runoff and tides on water age in Lianzhou Bay

NASA Astrophysics Data System (ADS)

Yu, Jing; Zhang, Xueqing; Liu, Jinliang; Liu, Rui; Wang, Xing

2016-09-01

The concept of water age is applied to calculate the timescales of the transport processes of freshwater in Lianzhou Bay, using a model based on ECOMSED. In this study, water age is defined as the time that has elapsed since the water parcel enters the Nanliu River. The results show that the mean age at a specified position and the runoff of the Nanliu River are well correlated and can be approximately expressed by a natural logarithmic function. During the neap tide, it takes 70, 60 and 40 days in the dry, normal and rainy seasons for water to travel from the mouth of the Nanliu River to the northeast of Lianzhou Bay, respectively, which is not beneficial to water exchange in the bay. Tides significantly influence the model results; it takes five less days for the tracer to be transported from the mouth of the Nanliu River to the north of Guantouling during the spring tide than during the neap tide.

First principles molecular dynamics of metal/water interfaces under bias potential

NASA Astrophysics Data System (ADS)

Pedroza, Luana; Brandimarte, Pedro; Rocha, Alexandre; Fernandez-Serra, Marivi

2014-03-01

Understanding the interaction of the water-metal system at an atomic level is extremely important in electrocatalysts for fuel cells, photocatalysis among other systems. The question of the interface energetics involves a detailed study of the nature of the interactions between water-water and water-substrate. A first principles description of all components of the system is the most appropriate methodology in order to advance understanding of electrochemically processes. In this work we describe, using first principles molecular dynamics simulations, the dynamics of a combined surface(Au and Pd)/water system both in the presence and absence of an external bias potential applied to the electrodes, as one would come across in electrochemistry. This is accomplished using a combination of density functional theory (DFT) and non-equilibrium Green's functions methods (NEGF), thus accounting for the fact that one is dealing with an out-of-equilibrium open system, with and without van der Waals interactions. DOE Early Career Award No. DE-SC0003871.

Pollution concentrations in runoff water from refuse piles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guin, J.A.

1977-03-01

In the processes of removal, refinement and disposal of raw materials, large quantities of waste products become exposed to weathering forces. Subsequent percolation, flushing, and oxidation results in the pollution of waterways, low-lying farmlands and underground aquifers with acidity, alkalinity, hardness, heavy metals, and undesirable organic materials such as tannin and lignin. The need for methodology for estimating the chemical nature and quantity of these leachates becomes more compelling as the extraction of natural materials accelerates. In this work a mass transfer model is formulated which describes the leaching of such pollutants from refuse piles. The model is applied tomore » an actual refuse pile under natural precipitation and weathering conditions and found to adequately represent the pollutant concentrations in the rainfall runoff.« less

Redox processes and water quality of selected principal aquifer systems

USGS Publications Warehouse

McMahon, P.B.; Chapelle, F.H.

2008-01-01

Reduction/oxidation (redox) conditions in 15 principal aquifer (PA) systems of the United States, and their impact on several water quality issues, were assessed from a large data base collected by the National Water-Quality Assessment Program of the USGS. The logic of these assessments was based on the observed ecological succession of electron acceptors such as dissolved oxygen, nitrate, and sulfate and threshold concentrations of these substrates needed to support active microbial metabolism. Similarly, the utilization of solid-phase electron acceptors such as Mn(IV) and Fe(III) is indicated by the production of dissolved manganese and iron. An internally consistent set of threshold concentration criteria was developed and applied to a large data set of 1692 water samples from the PAs to assess ambient redox conditions. The indicated redox conditions then were related to the occurrence of selected natural (arsenic) and anthropogenic (nitrate and volatile organic compounds) contaminants in ground water. For the natural and anthropogenic contaminants assessed in this study, considering redox conditions as defined by this framework of redox indicator species and threshold concentrations explained many water quality trends observed at a regional scale. An important finding of this study was that samples indicating mixed redox processes provide information on redox heterogeneity that is useful for assessing common water quality issues. Given the interpretive power of the redox framework and given that it is relatively inexpensive and easy to measure the chemical parameters included in the framework, those parameters should be included in routine water quality monitoring programs whenever possible.

Assessing the Total Economic Value of Improving Water Quality to Inform Water Resources Management: Evidence and Challenges from Southeast Asia

NASA Astrophysics Data System (ADS)

Jalilov, S.; Fukushi, K.

2016-12-01

Population growth, high rates of economic development and rapid urbanization in the developing countries of Southeast Asia (SEA) have resulted in degradation and depletion of natural resources, including water resources and related ecosystem services. Many urban rivers in the region are highly polluted with domestic, industrial and agricultural wastes. Policymakers are often aware of the direct value of water resources for domestic and industrial consumption, but they often underestimate the indirect value of these functions, since they are not exchanged in the market and do not appear in national income accounts. Underestimation of pollution and over-exploitation of water resources result in a loss of these benefits and have adverse impacts on nearby residents, threatening the long-term sustainable development of natural resources in the region. Behind these constraints lies a lack of knowledge (ignorance) from governments that a clean water environment could bring significant economic benefits. This study has been initiated to tackle this issue and to foster a more rational approach for sustainable urban development in Metro Manila in the Philippines. We applied a Contingent Valuation Method (CVM) based on Computer-Assisted Personal Interviewing (CAPI) technique. Results show that users are willing to pay up to PHP 102.42 (2.18) monthly to improve quality of urban waterbodies whereas nonusers are willing to pay up to PHP 366.53 (7.80) as one-time payment towards water quality improvement. The estimated monetary value of water quality improvements would be a useful variable in cost-benefit analyses of various water quality-related policies, in both public and private sectors in Metro Manila. This survey design could serve as a useful template for similar water quality studies in other SEA countries.

Modeling Modern Methane Emissions from Natural Wetlands. 1; Model Description and Results

NASA Technical Reports Server (NTRS)

Walter, Bernadette P.; Heimann, Martin; Matthews, Elaine

2001-01-01

Methane is an important greenhouse gas which contributes about 22 percent to the present greenhouse effect. Natural wetlands currently constitute the biggest methane source and were the major source in preindustrial times. Wetland emissions depend highly on the climate, i.e., on soil temperature and water table. To investigate the response of methane emissions from natural wetlands to climate variations, a process-based model that derives methane emissions from natural wetlands as a function of soil temperature, water table, and net primary productivity is used. For its application on the global scale, global data sets for all model parameters are generated. In addition, a simple hydrologic model is developed in order to simulate the position of the water table in wetlands. The hydrologic model is tested against data from different wetland sites, and the sensitivity of the hydrologic model to changes in precipitation is examined. The global methane­ hydrology model constitutes a tool to study temporal and spatial variations in methane emissions from natural wetlands. The model is applied using high-frequency atmospheric forcing fields from European Center for Medium-range Weather Forecasts (ECMWF) re-analyses of the period from 1982 to 1993. We calculate global annual methane emissions from wetlands to be 260 teragrams per year. Twenty-five percent of these methane emissions originate from wetlands north of 30 degrees North Latitude. Only 60 percent of the produced methane is emitted, while the rest is re-oxidized. A comparison of zonal integrals of simulated global wetland emissions and results obtained by an inverse modeling approach shows good agreement. In a test with data from two wetlands the seasonality of simulated and observed methane emissions agrees well.

Numerical study on criteria for design and operation of water curtain system in underground oil storage cavern using site descriptive fracture networks

NASA Astrophysics Data System (ADS)

Moon, Jiwon; Yeo, In Wook

2013-04-01

Underground unlined caverns have been constructed in fractured rocks to stockpile oil and petroleum products, where they are hydraulically contained by natural groundwater pressure. However, for the case that natural groundwater pressure is not maintained at the required level, water curtain boreholes, through which water is injected, are often constructed above the cavern as engineering barrier to secure water pressure enough to overwhelm the operational pressure of the cavern. For secure containment of oil and petroleum products inside the cavern, it is essential to keep water pressure around the cavern higher than operational pressure of the cavern using either natural groundwater pressure or engineering barrier. In the Republic of Korea, a number of underground stockpile bases are being operated by Korea National Oil Corporation (KNOC) and private companies, most of which have water curtain system. The criterion that KNOC adopts for water curtain system design and operation such as the vertical distance from the cavern and operational injection rate is based on the Åberg hypothesis that the vertical hydraulic gradient should be larger than one. The criterion has been used for maintaining oil storage cavern without its thorough review. In this study, systematic numerical works have been done for reviewing the Åberg criterion. As groundwater predominantly takes places through fractures in underground caverns, discrete fracture modeling approach is essential for this study. Fracture data, obtained from boreholes drilled at the stage of site investigation at the Yeosu stockpile base in Korea, were statistically analyzed in terms of orientation and intensity, which were used to generate the site descriptive three dimensional fracture networks. Then, groundwater flow modeling has been carried out for the fracture networks. Constant head boundaries were applied along the circumference of the cavern and water curtain boreholes. Main flow channel and hydraulic connectivity between water curtain boreholes and the caverns have been identified, along which hydraulic heads are monitored to find out whether the required hydraulic pressure is maintained around the cavern. The flow modeling has been repeatedly carried out at different constant head boundary conditions to create the criterion for the optimal operation of water curtain system.

Water management in Angkor: human impacts on hydrology and sediment transportation.

PubMed

Kummu, Matti

2009-03-01

The city of Angkor, capital of the Khmer empire from the 9th to 15th century CE, is well known for its impressive temples, but recent research has uncovered an extensive channel network stretching across over 1000 km2. The channel network with large reservoirs (termed baray) formed the structure of the city and was the basis for its water management. The annual long dry season associated with the monsoon climate has challenged water management for centuries, and the extensive water management system must have played an important role in the mitigation of such marked seasonality. However, by changing the natural water courses with off-take channels the original catchments were also reshaped. Moreover, severe problems of erosion and sedimentation in human built channels evolved and impacted on the whole water management system. This paper describes the present hydrology of the area and discusses the impacts of water management on hydrology during the Angkor era. The paper, moreover, attempts to summarise lessons that could be learnt from Angkorian water management that might apply to present challenges within the field.

Laboratory and pilot-scale field experiments for application of iron oxide nanoparticle-loaded chitosan composites to phosphate removal from natural water.

PubMed

Kim, Jae-Hyun; Kim, Song-Bae; Lee, Sang-Hyup; Choi, Jae-Woo

2018-03-01

The aim of this study was to apply iron oxide nanoparticle-chitosan (ION-chitosan) composites to phosphate removal from natural water collected from the Seoho Stream in Suwon, Republic of Korea. Laboratory batch experiments showed that phosphate removal by the ION-chitosan composites was not sensitive to pH changes between pH values of 5.0 and 9.0. During six cycles of adsorption-desorption, the composites could be successfully regenerated with 5 mM NaOH solution and reused for phosphate removal. Laboratory fixed-bed column experiments (column height = 10 and 20 cm, inner diameter = 2.5 cm, flow rate = 8.18 and 16.36 mL/min) demonstrated that the composites could be successfully applied for phosphate removal under dynamic flow conditions. A pilot-scale field experiment was performed in a pilot plant, which was mainly composed of chemical reactor/dissolved air flotation and an adsorption tower, built nearby the Seoho Stream. The natural water was pumped from the Seoho Stream into the pilot plant, passed through the chemical reactor/dissolved air flotation process, and then introduced into the adsorption tower (height = 100 cm, inner diameter = 45 cm, flow rate = 7.05 ± 0.18 L/min) for phosphate removal via the composites (composite volume = 80 L, composite weight = 85.74 kg). During monitoring of the adsorption tower (33 days), the influent total phosphorus (T-P) concentration was in the range of 0.020-0.046 mgP/L, whereas the effluent T-P concentration was in the range of 0.010-0.028 mgP/L. The percent removal of T-P in the adsorption tower was 52.3% with a phosphate removal capacity of 0.059 mgP/g.

Potentials and problems of sustainable irrigation with water high in salts

NASA Astrophysics Data System (ADS)

Ben-Gal, Alon

2015-04-01

Water scarcity and need to expand agricultural productivity have led to ever growing utilization of poor quality water for irrigation of crops. Almost in all cases, marginal or alternative water sources for irrigation contain relatively high concentrations of dissolved salts. When salts are present, irrigation water management, especially in the dry regions where water requirements are highest, must consider leaching in addition to crop evapotranspiration requirements. Leaching requirements for agronomic success are calculable and functions of climate, soil, and very critically, of crop sensitivity and the actual salinity of the irrigation water. The more sensitive the crop and more saline the water, the higher the agronomic cost and the greater the quantitative need for leaching. Israel is a forerunner in large-scale utilization of poor quality water for irrigation and can be used as a case study looking at long term repercussions of policy alternatively encouraging irrigation with recycled water or brackish groundwater. In cases studied in desert conditions of Israel, as much of half of the water applied to crops including bell peppers in greenhouses and date palms is actually used to leach salts from the root zone. The excess water used to leach salts and maintain agronomic and economic success when irrigating with water containing salts can become an environmental hazard, especially in dry areas where natural drainage is non-existent. The leachate often contains not only salts but also agrochemicals including nutrients, and natural contaminants can be picked up and transported as well. This leachate passes beyond the root zone and eventually reaches ground or surface water resources. This, together with evidence of ongoing increases in sodium content of fresh produce and increased SAR levels of soils, suggest that the current policy and practice in Israel of utilization of high amounts of low quality irrigation water is inherently non- sustainable. Current trends and technologies allowing economically feasible desalination at large scales present a sustainable alternative where salts are removed from water prior to irrigation.

Bioremediation of petroleum hydrocarbon-contaminated ground water: The perspectives of history and hydrology

USGS Publications Warehouse

Chapelle, F.H.

1999-01-01

Bioremediation, the use of microbial degradation processes to detoxify environmental contamination, was first applied to petroleum hydrocarbon-contaminated ground water systems in the early 1970s. Since that time, these technologies have evolved in some ways that were clearly anticipated early investigators, and in other ways that were not foreseen. The expectation that adding oxidants and nutrients to contaminated aquifers would enhance biodegradation, for example, has been born out subsequent experience. Many of the technologies now in common use such as air sparging, hydrogen peroxide addition, nitrate addition, and bioslurping, are conceptually similar to the first bioremediation systems put into operation. More unexpected, however, were the considerable technical problems associated with delivering oxidants and nutrients to heterogeneous ground water systems. Experience has shown that the success of engineered bioremediation systems depends largely on how effectively directions and rates of ground water flow can be controlled, and thus how efficiently oxidants and nutrients can be delivered to contaminated aquifer sediments. The early expectation that injecting laboratory-selected or genetically engineered cultures of hydrocarbon-degrading bacteria into aquifers would be a useful bioremediation technology has not been born out subsequent experience. Rather, it appears that petroleum hydrocarbon-degrading bacteria are ubiquitous in ground water systems and that bacterial addition is usually unnecessary. Perhaps the technology that was least anticipated early investigators was the development of intrinsic bioremediation. Experience has shown that natural attenuation mechanisms - biodegradation, dilution, and sorption - limit the migration of contaminants to some degree in all ground water systems. Intrinsic bioremediation is the deliberate use of natural attenuation processes to treat contaminated ground water to specified concentration levels at predetermined points in the aquifer. In current practice, intrinsic bioremediation of petroleum hydrocarbons requires a systematic assessment to show that ambient natural attenuation mechanisms are efficient enough to meet regulatory requirements and a monitoring program to verify that performance requirements are met in the future.

Optimizing Noble Gas-Water Interactions via Monte Carlo Simulations.

PubMed

Warr, Oliver; Ballentine, Chris J; Mu, Junju; Masters, Andrew

2015-11-12

In this work we present optimized noble gas-water Lennard-Jones 6-12 pair potentials for each noble gas. Given the significantly different atomic nature of water and the noble gases, the standard Lorentz-Berthelot mixing rules produce inaccurate unlike molecular interactions between these two species. Consequently, we find simulated Henry's coefficients deviate significantly from their experimental counterparts for the investigated thermodynamic range (293-353 K at 1 and 10 atm), due to a poor unlike potential well term (εij). Where εij is too high or low, so too is the strength of the resultant noble gas-water interaction. This observed inadequacy in using the Lorentz-Berthelot mixing rules is countered in this work by scaling εij for helium, neon, argon, and krypton by factors of 0.91, 0.8, 1.1, and 1.05, respectively, to reach a much improved agreement with experimental Henry's coefficients. Due to the highly sensitive nature of the xenon εij term, coupled with the reasonable agreement of the initial values, no scaling factor is applied for this noble gas. These resulting optimized pair potentials also accurately predict partitioning within a CO2-H2O binary phase system as well as diffusion coefficients in ambient water. This further supports the quality of these interaction potentials. Consequently, they can now form a well-grounded basis for the future molecular modeling of multiphase geological systems.

Potentiality of a fruit peel (banana peel) toward abatement of fluoride from synthetic and underground water samples collected from fluoride affected villages of Birbhum district

NASA Astrophysics Data System (ADS)

Mondal, Naba Kumar; Roy, Arunabha

2018-06-01

Contamination of underground water with fluoride (F) is a tremendous health hazard. Excessive F (> 1.5 mg/L) in drinking water can cause both dental and skeletal fluorosis. A fixed-bed column experiments were carried out with the operating variables such as different initial F concentrations, bed depths, pH and flow rates. Results revealed that the breakthrough time and exhaustion time decrease with increasing flow rate, decreasing bed depth and increasing influent fluoride concentration. The optimized conditions are: 10 mg/L initial fluoride concentration; flow rate 3.4 mL/min, bed depth 3.5 and pH 5. The bed depth service time model and the Thomas model were applied to the experimental results. Both the models were in good agreement with the experimental data for all the process parameters studied except flow rate, indicating that the models were appropriate for removal of F by natural banana peel dust in fix-bed design. Moreover, column adsorption was reversible and the regeneration was accomplished by pumping of 0.1 M NaOH through the loaded banana peel dust column. On the other hand, field water sample analysis data revealed that 86.5% fluoride can be removed under such optimized conditions. From the experimental results, it may be inferred that natural banana peel dust is an effective adsorbent for defluoridation of water.

Linking water quality guidelines to the natural characteristics of catchments in order to support distinct aquatic ecosystems: Water quality guidelines for suspended particulate matter

NASA Astrophysics Data System (ADS)

Bilotta, G. S.; Grove, M. K.; Harrison, C.; Joyce, C. B.; Peacock, C.

2012-12-01

The natural characteristics of a catchment provide a template that controls the background rates of geomorphological processes operating within that catchment, which in-turn determines the background physico-chemical and hydro-morphological characteristics of the catchment's surface waters. Large differences in the natural characteristics of catchments (e.g. geology, topography, climate), lead to unique physico-chemical and hydro-morphological conditions that support unique freshwater communities. However, this uniqueness is not always recognised in international water quality guidelines, which often attempt to apply blanket water-quality guidelines to 'protect' a wide range of ecosystems. In this paper we investigate the natural characteristics that control background concentrations of suspended particulate matter (SPM - including nano-scale particles to sand-sized sediments), which is a well-known cause of ecological degradation. At present, the management of SPM is hampered by a lack of understanding of the SPM conditions that water quality managers should aim to achieve in contrasting environments in order to support good ecological status. To address this, in this paper we examine the SPM preferences of contrasting biological communities that are in reference condition (minimal anthropogenic disturbance and high ecological status). We analyse historical SPM data collected on a monthly basis from a wide range of reference-condition temperate environments (638 stream/river sites comprising 42 different biological community-types). This analysis reveals that there are statistically significant differences (One-way ANOVA p < 0.001) between the background SPM concentrations observed in contrasting communities that are in reference condition. Mean background SPM concentrations for contrasting communities ranged from 1.7 to 26.2 mg L-1 (i.e. more than a 15-fold difference). We propose a model for predicting environment-specific water quality guidelines for SPM. In order to develop this model, the 638 reference-condition sites were first classified into one of five mean background SPM ranges (0.00-5.99, 6.00-11.99, 12.00-17.99, 18.00-23.99 and >24.00 mg L-1). Stepwise Multiple Discriminant Analysis (MDA) of these ranges showed that a site's SPM range can be predicted as a function of: mean annual air temperature, mean annual precipitation, mean altitude of upstream catchment, distance from source, slope to source, channel width and depth, the percentage of catchment area comprised of clay, chalk, and hard rock solid geology, and the percentage of the catchment area comprised of blown sand/landslide material as the surface (drift) material. Although the model is still being improved and developed, this research highlights the need to link water quality guidelines to the natural characteristics of catchments and the physico-chemical preferences of the biological communities that would naturally inhabit them.

Airborne DOAS retrievals of methane, carbon dioxide, and water vapor concentrations at high spatial resolution: application to AVIRIS-NG

NASA Astrophysics Data System (ADS)

Thorpe, Andrew K.; Frankenberg, Christian; Thompson, David R.; Duren, Riley M.; Aubrey, Andrew D.; Bue, Brian D.; Green, Robert O.; Gerilowski, Konstantin; Krings, Thomas; Borchardt, Jakob; Kort, Eric A.; Sweeney, Colm; Conley, Stephen; Roberts, Dar A.; Dennison, Philip E.

2017-10-01

At local scales, emissions of methane and carbon dioxide are highly uncertain. Localized sources of both trace gases can create strong local gradients in its columnar abundance, which can be discerned using absorption spectroscopy at high spatial resolution. In a previous study, more than 250 methane plumes were observed in the San Juan Basin near Four Corners during April 2015 using the next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) and a linearized matched filter. For the first time, we apply the iterative maximum a posteriori differential optical absorption spectroscopy (IMAP-DOAS) method to AVIRIS-NG data and generate gas concentration maps for methane, carbon dioxide, and water vapor plumes. This demonstrates a comprehensive greenhouse gas monitoring capability that targets methane and carbon dioxide, the two dominant anthropogenic climate-forcing agents. Water vapor results indicate the ability of these retrievals to distinguish between methane and water vapor despite spectral interference in the shortwave infrared. We focus on selected cases from anthropogenic and natural sources, including emissions from mine ventilation shafts, a gas processing plant, tank, pipeline leak, and natural seep. In addition, carbon dioxide emissions were mapped from the flue-gas stacks of two coal-fired power plants and a water vapor plume was observed from the combined sources of cooling towers and cooling ponds. Observed plumes were consistent with known and suspected emission sources verified by the true color AVIRIS-NG scenes and higher-resolution Google Earth imagery. Real-time detection and geolocation of methane plumes by AVIRIS-NG provided unambiguous identification of individual emission source locations and communication to a ground team for rapid follow-up. This permitted verification of a number of methane emission sources using a thermal camera, including a tank and buried natural gas pipeline.

Runoff water quality from broiler litter-amended tall fescue in response to natural precipitation in the Ozark Highlands.

PubMed

Menjoulet, B C; Brye, K R; Pirani, A L; Haggard, B E; Gbur, E E

2009-01-01

The Arkansas poultry industry produced more than 1.2 billion broiler chickens (Gallus gallus domesticus) and generated approximately 1.3 million Mg of broiler litter in 2002. High transportation costs of relocating broiler litter have led to annual land applications near poultry houses, increasing concern for potential surface water contamination from runoff. The objective of this study was to evaluate the effect of broiler litter application rate on runoff water quality in response to natural precipitation. Six plots (1.5 by 6.0 m), located on a Captina silt loam (finesilty, siliceous, active, mesic Typic Fragiudult), were amended with fresh broiler litter at 0, 5.6, and 11.2 Mg ha(-1) (control, low, and high litter treatments, respectively) once annually for 4 yr (May 2003 through April 2007). Runoff collected after each runoff-producing event was analyzed for soluble nutrients and metals. Cumulative runoff did not differ among litter treatments over the 4-yr study. At times, flow-weighted mean (FWM) concentrations of As from all litter treatments exceeded the maximum contaminant level for drinking water (0.01 mg As L(-1)). Four-year FWM Fe concentrations and runoff losses were greater (P < 0.05) from the high than from the low litter treatment and unamended control, and the 4-yr FWM P concentration from the low litter treatment (3.0 mg L(-1)) was greater than that from the unamended control (1.8 mg L(-1)). Since precipitation is temporally variable, evaluating runoff water quality in response to natural precipitation over several years is key to ascertaining the long-term impacts of surface-applied soil amendments like broiler litter.

Conservation and sustainability in freshwater ecosystems in Tavira (Portugal)

NASA Astrophysics Data System (ADS)

Gonçalves, Esmeralda; Fonseca, José; Lopes, Luís; João Costa, Maria; Cunha, Miguel

2013-04-01

This interdisciplinary project carried out with 8th and 9th grade students involved five teachers from three different subjects (Physics and Chemistry, Natural Science and Geography). Framed in the Water Framework Directive, it aimed at verifying the ecological quality of water in two rivers in the municipality of Tavira (South Portugal). The development of this project has been structured in accordance with the following objectives: evaluate the quality of freshwater ecosystems through the existence of certain living organisms; present proposals on ways to preserve water resources in a sustainable perspective; sensitize students to the importance of their participation in collective action by volunteering for ecological protection. This is an innovative educational experience that allowed students an integrated approach to content and procedures applied to real problems in their local environment.

The Feasibility of Establishing Operational Water Hyacinth-Based Systems at the Treatment Facilities of Existing Cities. [in Florida and Texas

NASA Technical Reports Server (NTRS)

1977-01-01

The wastewater treatment facilities of three communities in southern Florida and two in southern Texas areas having populations of 20,000 or fewer persons were surveyed to determine: (1) their performance characteristics and the nature of their customers; (2) facility upgrading requirements needed to meet current and future EPA and State standards; (3) their adaptability to water hyacinth utilization and harvested plant disposal; and (4) the level of community support. Guidelines for site selection were established and applied to five cities in Texas and four in Florida. An evaluation of the prospective sites reveals that the Florida locations are generally unsuitable for implementation of water hyacinth based systems because of regulatory philosophy. All five Texas sites have excellent potential.

Fluid-Structure Interaction of Channel Driven Cavity Flow

DTIC Science & Technology

2016-06-01

3 32 ") thick neoprene rubber sheet. The sheet was bonded to the acrylic using 3M Scotch- Weld Neoprene High Performance Rubber and Gasket Adhesive...TABLES Table 1. Natural Frequencies of the 0.5 mm (0.02”) Thick Aluminum Plate ..........19 Table 2. Mean Normalized Strains...1300. A bead of 100% silicone was applied on the bond to prevent water from infiltrating the adhesive. The 3M Scotch- Weld 1300 adhesive kept the

A hydro-meteorological model chain to assess the influence of natural variability and impacts of climate change on extreme events and propose optimal water management

NASA Astrophysics Data System (ADS)

von Trentini, F.; Willkofer, F.; Wood, R. R.; Schmid, F. J.; Ludwig, R.

2017-12-01

The ClimEx project (Climate change and hydrological extreme events - risks and perspectives for water management in Bavaria and Québec) focuses on the effects of climate change on hydro-meteorological extreme events and their implications for water management in Bavaria and Québec. Therefore, a hydro-meteorological model chain is applied. It employs high performance computing capacity of the Leibniz Supercomputing Centre facility SuperMUC to dynamically downscale 50 members of the Global Circulation Model CanESM2 over European and Eastern North American domains using the Canadian Regional Climate Model (RCM) CRCM5. Over Europe, the unique single model ensemble is conjointly analyzed with the latest information provided through the CORDEX-initiative, to better assess the influence of natural climate variability and climatic change in the dynamics of extreme events. Furthermore, these 50 members of a single RCM will enhance extreme value statistics (extreme return periods) by exploiting the available 1500 model years for the reference period from 1981 to 2010. Hence, the RCM output is applied to drive the process based, fully distributed, and deterministic hydrological model WaSiM in high temporal (3h) and spatial (500m) resolution. WaSiM and the large ensemble are further used to derive a variety of hydro-meteorological patterns leading to severe flood events. A tool for virtual perfect prediction shall provide a combination of optimal lead time and management strategy to mitigate certain flood events following these patterns.

Identifying and assessing ecotourism visitor impacts at selected protected areas in Costa Rica and Belize

USGS Publications Warehouse

Farrell, T.A.; Marion, J.L.

2001-01-01

Protected area visitation is an important component of ecotourism, and as such, must be sustainable. However, protected area visitation may degrade natural resources, particularly in areas of concentrated visitor activities like trails and recreation sites. This is an important concern in ecotourism destinations such as Belize and Costa Rica, because they actively promote ecotourism and emphasize the pristine qualities of their natural resources. Research on visitor impacts to protected areas has many potential applications in protected area management, though it has not been widely applied in Central and South America. This study targeted this deficiency through manager interviews and evaluations of alternative impact assessment procedures at eight protected areas in Belize and Costa Rica. Impact assessment procedures included qualitative condition class systems, ratings systems, and measurement-based systems applied to trails and recreation sites. The resulting data characterize manager perceptions of impact problems, document trail and recreation site impacts, and provide examples of inexpensive, efficient and effective rapid impact assessment procedures. Interview subjects reported a variety of impacts affecting trails, recreation sites, wildlife, water, attraction features and other resources. Standardized assessment procedures were developed and applied to record trail and recreation site impacts. Impacts affecting the study areas included trail proliferation, erosion and widening, muddiness on trails, vegetation cover loss, soil and root exposure, and tree damage on recreation sites. The findings also illustrate the types of assessment data yielded by several alternative methods and demonstrate their utility to protected area managers. The need for additional rapid assessment procedures for wildlife, water, attraction feature and other resource impacts was also identified.

Quantitative Analysis of Existing Conditions and Production Strategies for the Baca Geothermal System, New Mexico

NASA Astrophysics Data System (ADS)

Faust, Charles R.; Mercer, James W.; Thomas, Stephen D.; Balleau, W. Pete

1984-05-01

The Baca geothermal reservoir and adjacent aquifers in the Jemez Mountains of New Mexico comprise an integrated hydrogeologic system. Analysis of the geothermal reservoir either under natural conditions or subject to proposed development should account for the mass (water) and energy (heat) balances of adjacent aquifers as well as the reservoir itself. A three-dimensional model based on finite difference approximations is applied to this integrated system. The model simulates heat transport associated with the flow of steam and water through an equivalent porous medium. The Baca geothermal reservoir is dominated by flow in fractures and distinct strata, but at the scale of application the equivalent porous media concept is appropriate. The geothermal reservoir and adjacent aquifers are simulated under both natural conditions and proposed production strategies. Simulation of natural conditions compares favorably with observed pressure, temperature, and thermal discharge data. The history matching simulations show that the results used for comparison are most sensitive to vertical permeability and the area of an assumed high-permeability zone connecting the reservoir to a deep hydrothermal source. Simulations using proposed production strategies and optimistic estimates of certain hydrologic parameters and reservoir extent indicate that a 50-MW power plant could be maintained for a period greater than 30 years. This production, however, will result in significant decreases in the total water discharge to the Jemez River.

Automated method for the determination of total arsenic and selenium in natural and drinking water by HG-AAS.

PubMed

Pistón, Mariela; Silva, Javier; Pérez-Zambra, Ramiro; Dol, Isabel; Knochen, Moisés

2012-04-01

A multicommutated flow system was designed and evaluated for the determination of total arsenic and selenium by Hydride Generation Atomic Absorption Spectrometry (HG-AAS). It was applied to the determination of arsenic and selenium in samples of natural and drinking water. Detection limits were 0.46 and 0.08 μg l(-1) for arsenic and selenium, respectively; sampling frequency was 120 samples h(-1) for arsenic and 160 samples h(-1) for selenium. Linear ranges found were 1.54-10 μg l(-1) (R = 0.999) for arsenic and 0.27-27 μg l(-1) (R = 0.999) for selenium. Accuracy was evaluated by spiking various water samples and using a reference material. Recoveries were in the range 95-116%. Analytical precision (s ( r ) (%), n = 10) was 6% for both elements. Compared with the Standard Methods, APHA, 3114B manual method, the system consumes at least 10 times less sample per determination, and the quantities of acid and reducing agent used are significantly lower with a reduction in the generation of pollutants and waste. As an additional advantage, the system is very fast, efficient and environmentally friendly for monitoring total arsenic and selenium levels in waters.

Effects of increasing forest plantation area and management practices on carbon storage and water use in the United States

NASA Astrophysics Data System (ADS)

Chen, G.; Hayes, D. J.; Tian, H.

2013-12-01

Planted forest area in the United States gradually increased during the last half century, and by 2007 accounted for about 20% of the total forest area in the southern United States and about 13% in the entire country. Intensive plantation management activities - such as slash burning, thinning, weed control, fertilization and the use of genetically improved seedlings - are routinely applied during the forest rotation. However, no comprehensive assessments have been made to examine the impacts of this increased forest plantation area and associated management practices on ecosystem function. In this study, we integrated field measurement data and process-based modeling to quantitatively estimate the changes in carbon storage, nitrogen cycling and water use as influenced by forest plantations in the United States from 1925 to 2007. The results indicated that forest plantations and management practices greatly increased forest productivity, vegetation carbon, and wood product carbon storage in the United States, but slightly reduce soil carbon storage at some areas; however, the carbon sink induced by forest plantations was at the expense of more water use as represented by higher evapotranspiration. Stronger nitrogen and water limitations were found for forest plantations as compared to natural or naturally-regenerated forests.

Sex differences in virtual navigation influenced by scale and navigation experience.

PubMed

Padilla, Lace M; Creem-Regehr, Sarah H; Stefanucci, Jeanine K; Cashdan, Elizabeth A

2017-04-01

The Morris water maze is a spatial abilities test adapted from the animal spatial cognition literature and has been studied in the context of sex differences in humans. This is because its standard design, which manipulates proximal (close) and distal (far) cues, applies to human navigation. However, virtual Morris water mazes test navigation skills on a scale that is vastly smaller than natural human navigation. Many researchers have argued that navigating in large and small scales is fundamentally different, and small-scale navigation might not simulate natural human navigation. Other work has suggested that navigation experience could influence spatial skills. To address the question of how individual differences influence navigational abilities in differently scaled environments, we employed both a large- (146.4 m in diameter) and a traditional- (36.6 m in diameter) scaled virtual Morris water maze along with a novel measure of navigation experience (lifetime mobility). We found sex differences on the small maze in the distal cue condition only, but in both cue-conditions on the large maze. Also, individual differences in navigation experience modulated navigation performance on the virtual water maze, showing that higher mobility was related to better performance with proximal cues for only females on the small maze, but for both males and females on the large maze.

Are the defined substrate-based methods adequate to determine the microbiological quality of natural recreational waters?

PubMed

Valente, Marta Sofia; Pedro, Paulo; Alonso, M Carmen; Borrego, Juan J; Dionísio, Lídia

2010-03-01

Monitoring the microbiological quality of water used for recreational activities is very important to human public health. Although the sanitary quality of recreational marine waters could be evaluated by standard methods, they are time-consuming and need confirmation. For these reasons, faster and more sensitive methods, such as the defined substrate-based technology, have been developed. In the present work, we have compared the standard method of membrane filtration using Tergitol-TTC agar for total coliforms and Escherichia coli, and Slanetz and Bartley agar for enterococci, and the IDEXX defined substrate technology for these faecal pollution indicators to determine the microbiological quality of natural recreational waters. ISO 17994:2004 standard was used to compare these methods. The IDEXX for total coliforms and E. coli, Colilert, showed higher values than those obtained by the standard method. Enterolert test, for the enumeration of enterococci, showed lower values when compared with the standard method. It may be concluded that more studies to evaluate the precision and accuracy of the rapid tests are required in order to apply them for routine monitoring of marine and freshwater recreational bathing areas. The main advantages of these methods are that they are more specific, feasible and simpler than the standard methodology.

Web-based modelling of energy, water and matter fluxes to support decision making in mesoscale catchments??the integrative perspective of GLOWA-Danube

NASA Astrophysics Data System (ADS)

Ludwig, R.; Mauser, W.; Niemeyer, S.; Colgan, A.; Stolz, R.; Escher-Vetter, H.; Kuhn, M.; Reichstein, M.; Tenhunen, J.; Kraus, A.; Ludwig, M.; Barth, M.; Hennicker, R.

The GLOWA-initiative (Global Change of the water cycle), funded by the German Ministry of Research and Education (BMBF), has been established to address the manifold consequences of Global Change on regional water resources in a variety of catchment areas with different natural and cultural characteristics. Within this framework, the GLOWA-Danube project is dealing with the Upper Danube watershed as a representative mesoscale test site (∼75.000 km 2) for mountain-foreland regions in the temperate mid-latitudes. The principle objective is to identify, examine and develop new techniques of coupled distributed modelling for the integration of natural and socio-economic sciences. The transdisciplinary research in GLOWA-Danube develops an integrated decision support system, called DANUBIA, to investigate the sustainability of future water use. GLOWA-Danube, which is scheduled for a total run-time of eight years to operationally implement and establish DANUBIA, comprises a university-based network of experts with water-related competence in the fields of engineering, natural and social sciences. Co-operation with a network of stakeholders in water resources management of the Upper Danube catchment ensures that practical issues and future problems in the water sector of the region can be addressed. In order to synthesize a common understanding between the project partners, a standardized notation of parameters and functions and a platform-independent structure of computational methods and interfaces has been established, by making use of the unified modelling language, an industry standard for the structuring and co-ordination of large projects in software development [Booch et al., The Unified Modelling Language User Guide, Addison-Wesley, Reading, 1999]. DANUBIA is object-oriented, spatially distributed and raster-based at its core. It applies the concept of “proxels” (process pixels) as its basic objects, which have different dimensions depending on the viewing scale and connect to their environment through fluxes. The presented paper excerpts the hydrological view point of GLOWA-Danube, its approach of model coupling and network-based communication, and object-oriented techniques to simulate physical processes and interactions at the land surface. The mechanisms and technologies applied to communicate data and model parameters across the typical discipline borders are demonstrated from the perspective of the Landsurface object. It comprises the capabilities of interdependent expert models for energy exchange at various surface types, snowmelt, soil water movement, runoff formation and plant growth in a distributed Java-based modelling environment using the remote method invocation [Pitt et al., Java.rmi: The Remote Method Invocation Guide, Addison Wesley Professional, Reading, 2001, p. 320]. The presented text summarizes the GLOWA-Danube concept and shows the state of an implemented DANUBIA prototype after completion of the first project-year (2001).

Inactivation of Bacteria in Oil Field Injected Water by a Pulsed Plasma Discharge Process

NASA Astrophysics Data System (ADS)

Xin, Qing; Li, Zhongjian; Lei, Lecheng; Yang, Bin

2016-09-01

Pulsed plasma discharge was employed to inactivate bacteria in the injection water for an oil field. The effects of water conductivity and initial concentration of bacteria on elimination efficiency were investigated in the batch and continuous flow modes. It was demonstrated that Fe2+ contained in injection water could enhance the elimination efficiency greatly. The addition of reducing agent glutathione (GSH) indicated that active radicals generated by pulsed plasma discharges played an important role in the inactivation of bacteria. Moreover, it was found that the microbial inactivation process for both batch and continuous flow mode well fitted the model based on the Weibull's survival function. supported by Zhejiang Province Welfare Technology Applied Research Project of China (No. 2014C31137), National Natural Science Foundation of China (Nos. 21436007 and U1462201), and the Fundamental Research Funds for the Central Universities of China (No. 2015QNA4032)

Efficient electrochemical remediation of microcystin-LR in tap water using designer TiO2@carbon electrodes

NASA Astrophysics Data System (ADS)

Sanz Lobón, Germán; Yepez, Alfonso; Garcia, Luane Ferreira; Morais, Ruiter Lima; Vaz, Boniek Gontijo; Carvalho, Veronica Vale; de Oliveira, Gisele Augusto Rodrigues; Luque, Rafael; Gil, Eric De Souza

2017-02-01

Microcystin-leucine arginine (MC-LR) is the most abundant and toxic secondary metabolite produced by freshwater cyanobacteria. This toxin has a high potential hazard health due to potential interactions with liver, kidney and the nervous system. The aim of this work was the design of a simple and environmentally friendly electrochemical system based on highly efficient nanostructured electrodes for the removal of MC-LR in tap water. Titania nanoparticles were deposited on carbon (graphite) under a simple and efficient microwave assisted approach for the design of the electrode, further utilized in the electrochemical remediation assays. Parameters including the applied voltage, time of removal and pH (natural tap water or alkaline condition) were investigated in the process, with results pointing to a high removal efficiency for MC-LR (60% in tap water and 90% in alkaline media experiments, under optimized conditions).

Methane flux from the Central Amazonian Floodplain

NASA Technical Reports Server (NTRS)

Bartlett, Karen B.; Crill, Patrick M.; Sebacher, Daniel I.; Harriss, Robert C.; Wilson, John O.; Melack, John M.

1987-01-01

A total of 186 methane measurements from the three primary Amazon floodplain environments of open water lakes, flood forests, and floating grass mats were made over the period 18 July through 2 September 1985. These data indicate that emissions were lowest over open water lakes. Flux from flooded forests and grass mats was significantly higher. At least three transport processes contribute to tropospheric emissions: ebullition from sediments, diffusion along the concentration gradient from sediment to overlaying water to air, and transport through the roots and stems of aquatic plants. Measurements indicate that the first two of these processes are most significant. It was estimated that on the average bubbling makes up 49% of the flux from open water, 54% of that from flooded forests, and 64% of that from floating mats. If the measurements were applied to the entire Amazonian floodplain, it is calculated that the region could supply up to 12% of the estimated global natural sources of methane.

Efficient electrochemical remediation of microcystin-LR in tap water using designer TiO2@carbon electrodes

PubMed Central

Sanz Lobón, Germán; Yepez, Alfonso; Garcia, Luane Ferreira; Morais, Ruiter Lima; Vaz, Boniek Gontijo; Carvalho, Veronica Vale; de Oliveira, Gisele Augusto Rodrigues; Luque, Rafael; Gil, Eric de Souza

2017-01-01

Microcystin-leucine arginine (MC-LR) is the most abundant and toxic secondary metabolite produced by freshwater cyanobacteria. This toxin has a high potential hazard health due to potential interactions with liver, kidney and the nervous system. The aim of this work was the design of a simple and environmentally friendly electrochemical system based on highly efficient nanostructured electrodes for the removal of MC-LR in tap water. Titania nanoparticles were deposited on carbon (graphite) under a simple and efficient microwave assisted approach for the design of the electrode, further utilized in the electrochemical remediation assays. Parameters including the applied voltage, time of removal and pH (natural tap water or alkaline condition) were investigated in the process, with results pointing to a high removal efficiency for MC-LR (60% in tap water and 90% in alkaline media experiments, under optimized conditions). PMID:28145477

Discussion of the enabling environments for decentralised water systems.

PubMed

Moglia, M; Alexander, K S; Sharma, A

2011-01-01

Decentralised water supply systems are becoming increasingly affordable and commonplace in Australia and have the potential to alleviate urban water shortages and reduce pollution into natural receiving marine and freshwater streams. Learning processes are necessary to support the efficient implementation of decentralised systems. These processes reveal the complex socio-technical and institutional factors to be considered when developing an enabling environment supporting decentralised water and wastewater servicing solutions. Critical to the technological transition towards established decentralised systems is the ability to create strategic and adaptive capacity to promote learning and dialogue. Learning processes require institutional mechanisms to ensure the lessons are incorporated into the formulation of policy and regulation, through constructive involvement of key government institutions. Engagement of stakeholders is essential to the enabling environment. Collaborative learning environments using systems analysis with communities (social learning) and adaptive management techniques are useful in refining and applying scientists' and managers' knowledge (knowledge management).

Possible treatments for arsenic removal in Latin American waters for human consumption.

PubMed

Litter, Marta I; Morgada, Maria E; Bundschuh, Jochen

2010-05-01

Considering the toxic effects of arsenic, the World Health Organization recommends a maximum concentration of 10 microg L(-1) of arsenic in drinking water. Latin American populations present severe health problems due to consumption of waters with high arsenic contents. The physicochemical properties of surface and groundwaters are different from those of other more studied regions of the planet, and the problem is still publicly unknown. Methods for arsenic removal suitable to be applied in Latin American waters are here summarized and commented. Conventional technologies (oxidation, coagulation-coprecipitation, adsorption, reverse osmosis, use of ion exchangers) are described, but emphasis is made in emergent decentralized economical methods as the use of inexpensive natural adsorbents, solar light technologies or biological treatments, as essential to palliate the situation in poor, isolated and dispersed populations of Latin American regions. Copyright 2010 Elsevier Ltd. All rights reserved.

Comprehensive separation of secondary metabolites in natural products by high-speed counter-current chromatography using a three-phase solvent system.

PubMed

Yanagida, Akio; Yamakawa, Yutaka; Noji, Ryoko; Oda, Ako; Shindo, Heisaburo; Ito, Yoichiro; Shibusawa, Yoichi

2007-06-01

High-speed counter-current chromatography (HSCCC) using the three-phase solvent system n-hexane-methyl acetate-acetonitrile-water at a volume ratio of 4:4:3:4 was applied to the comprehensive separation of secondary metabolites in several natural product extracts. A wide variety of secondary metabolites in each natural product was effectively extracted with the three-phase solvent system, and the filtered extract was directly submitted to the HSCCC separation using the same three-phase system. In the HSCCC profiles of crude natural drugs listed in the Japanese Pharmacopoeia, several physiologically active compounds were clearly separated from other components in the extracts. The HSCCC profiles of several tea products, each manufactured by a different process, clearly showed their compositional difference in main compounds such as catechins, caffeine, and pigments. These HSCCC profiles also provide useful information about hydrophobic diversity of whole components present in each natural product.

Arsenic Cycling in Hydrocarbon Plumes: Secondary Effects of Natural Attenuation.

PubMed

Cozzarelli, Isabelle M; Schreiber, Madeline E; Erickson, Melinda L; Ziegler, Brady A

2016-01-01

Monitored natural attenuation is widely applied as a remediation strategy at hydrocarbon spill sites. Natural attenuation relies on biodegradation of hydrocarbons coupled with reduction of electron acceptors, including solid phase ferric iron (Fe(III)). Because arsenic (As) adsorbs to Fe-hydroxides, a potential secondary effect of natural attenuation of hydrocarbons coupled with Fe(III) reduction is a release of naturally occurring As to groundwater. At a crude-oil-contaminated aquifer near Bemidji, Minnesota, anaerobic biodegradation of hydrocarbons coupled to Fe(III) reduction has been well documented. We collected groundwater samples at the site annually from 2009 to 2013 to examine if As is released to groundwater and, if so, to document relationships between As and Fe inside and outside of the dissolved hydrocarbon plume. Arsenic concentrations in groundwater in the plume reached 230 µg/L, whereas groundwater outside the plume contained less than 5 µg/L As. Combined with previous data from the Bemidji site, our results suggest that (1) naturally occurring As is associated with Fe-hydroxides present in the glacially derived aquifer sediments; (2) introduction of hydrocarbons results in reduction of Fe-hydroxides, releasing As and Fe to groundwater; (3) at the leading edge of the plume, As and Fe are removed from groundwater and retained on sediments; and (4) downgradient from the plume, patterns of As and Fe in groundwater are similar to background. We develop a conceptual model of secondary As release due to natural attenuation of hydrocarbons that can be applied to other sites where an influx of biodegradable organic carbon promotes Fe(III) reduction. © 2015, National Ground Water Association.

Moving from local to State water governance to resolve a local conflict between irrigated agriculture and commercial forestry in South Australia

NASA Astrophysics Data System (ADS)

Gillet, Virginie; McKay, Jennifer; Keremane, Ganesh

2014-11-01

In the Lower Limestone Coast, South Australia, a unique water allocation plan has been under consideration for several years. This plan is the first in Australia to consider forestry as a water affecting activity. Indeed, forestry plantations have a twofold impact on water-rainfall or aquifer recharge interception and direct extraction of groundwater in shallow water table areas-and alter the available water for irrigation as a result of the previous water budget. This paper examines how water is allocated across the competing requirements for water but also across the competing legal, economic and administrative scales embodied by the competing water users; and thus it also details the pre-judicial mechanism used to resolve the conflict over these competing scales. Qualitative and quantitative content analysis in Nvivo was applied to: (i) 180 local newspaper articles on the planning process, (ii) 65 submission forms filled in by the community during a public consultation on the draft water plan and (iii) 20 face-to-face interviews of keys stakeholders involved in the planning process. The social sustainability perspective taken in this study establishes the legal, economic and administrative competitive scales at stake in the conflict regarding water between forestry and irrigation. It also evidences the special feature of this paper, which is that to overcome these competitions and resolve the local conflict before judicial process, the water governance moved up in the administrative scale, from local/regional to State level. Initiated and initially prepared at regional level through the local Natural Resources Management Board, the water planning process was taken up to State level through the formation of an Interdepartmental Committee and the establishment of a Taskforce in charge of developing a policy. These were supported by an amendment of a State legislation on Natural Resources Management to manage the water impacts of forestry plantations.

An Excel Workbook for Identifying Redox Processes in Ground Water

USGS Publications Warehouse

Jurgens, Bryant C.; McMahon, Peter B.; Chapelle, Francis H.; Eberts, Sandra M.

2009-01-01

The reduction/oxidation (redox) condition of ground water affects the concentration, transport, and fate of many anthropogenic and natural contaminants. The redox state of a ground-water sample is defined by the dominant type of reduction/oxidation reaction, or redox process, occurring in the sample, as inferred from water-quality data. However, because of the difficulty in defining and applying a systematic redox framework to samples from diverse hydrogeologic settings, many regional water-quality investigations do not attempt to determine the predominant redox process in ground water. Recently, McMahon and Chapelle (2008) devised a redox framework that was applied to a large number of samples from 15 principal aquifer systems in the United States to examine the effect of redox processes on water quality. This framework was expanded by Chapelle and others (in press) to use measured sulfide data to differentiate between iron(III)- and sulfate-reducing conditions. These investigations showed that a systematic approach to characterize redox conditions in ground water could be applied to datasets from diverse hydrogeologic settings using water-quality data routinely collected in regional water-quality investigations. This report describes the Microsoft Excel workbook, RedoxAssignment_McMahon&Chapelle.xls, that assigns the predominant redox process to samples using the framework created by McMahon and Chapelle (2008) and expanded by Chapelle and others (in press). Assignment of redox conditions is based on concentrations of dissolved oxygen (O2), nitrate (NO3-), manganese (Mn2+), iron (Fe2+), sulfate (SO42-), and sulfide (sum of dihydrogen sulfide [aqueous H2S], hydrogen sulfide [HS-], and sulfide [S2-]). The logical arguments for assigning the predominant redox process to each sample are performed by a program written in Microsoft Visual Basic for Applications (VBA). The program is called from buttons on the main worksheet. The number of samples that can be analyzed is only limited by the number of rows in Excel (65,536 for Excel 2003 and XP; and 1,048,576 for Excel 2007), and is therefore appropriate for large datasets.

Monitoring of estrogens, pesticides and bisphenol A in natural waters and drinking water treatment plants by solid-phase extraction-liquid chromatography-mass spectrometry.

PubMed

Rodriguez-Mozaz, Sara; de Alda, Maria J López; Barceló, Damià

2004-08-06

A multi-residue analytical method has been developed for the determination of various classes of selected endocrine disruptors. This method allows the simultaneous extraction and quantification of different estrogens (estradiol, estrone, estriol, estradiol-17-glucuronide, estradiol diacetate, estrone-3-sulfate, ethynyl estradiol and diethylstilbestrol), pesticides (atrazine, simazine, desethylatrazine, isoproturon and diuron), and bisphenol A in natural waters. In the method developed, 500 ml of water are preconcentrated on LiChrolut RP-18 cartridges. Further analysis is carried out by liquid chromatography-mass spectrometry (LC-MS) using atmospheric pressure chemical ionisation (APCI) in the positive ion mode for determination of pesticides and electrospray in the negative ionisation mode for determination of estrogens and bisphenol A. Recoveries for most compounds were between 90 and 119%, except for bisphenol A (81%) and diethylstilbestrol (70%), with relative standard deviations below 20%. Limits of detection ranged between 2 and 15 ng/l. The method was used to study the occurrence of the selected pollutants in surface and groundwater used for abstraction of drinking water in a waterworks and to evaluate the removal efficiency of the different water treatments applied. Water samples from the river, the aquifer, and after each treatment stage (sand filtration, ozonation, activated carbon filtration and post-chlorination) were taken monthly from February to August of 2002. The presence in river water of atrazine, simazine, diuron and bisphenol A were relatively frequent at concentrations usually below 0.1 microg/l. Lower levels, below 0.02 microg/l, were usual for isoproturon. Estrone-3-sulfate and estrone were detected occasionally in the river. Most of the compounds were completely removed during the water treatment, especially after activated carbon filtration.

A methodology for space-time classification of groundwater quality.

PubMed

Passarella, G; Caputo, M C

2006-04-01

Safeguarding groundwater from civil, agricultural and industrial contamination is matter of great interest in water resource management. During recent years, much legislation has been produced stating the importance of groundwater as a source for drinking water supplies, underlining its vulnerability and defining the required quality standards. Thus, schematic tools, able to characterise the quality and quantity of groundwater systems, are of very great interest in any territorial planning and/or water resource management activity. This paper proposes a groundwater quality classification method which has been applied to a real aquifer, starting from several studies published by the Italian National Hydrogeologic Catastrophe Defence Group (GNDCI). The methodology is based on the concentration values of several parameters used as indexes of the natural hydro-chemical water condition and of potential man-induced modifications of groundwater quality. The resulting maps, although representative of the quality, do not include any information on its evolution in time. In this paper, this "stationary" classification method has been improved by crossing the quality classes with three indexes of temporal behaviour during recent years. It was then applied to data from monitoring campaigns, performed in spring and autumn, from 1990 to 1996, in the plain of Modena aquifer (central Italy). The results are reported in the form of space-time classification table and maps.

Assessing vulnerability mapping and protection zones of karst spring waters and validating by the joint use of natural and artificial tracers. The case of Auta Spring (Southern Spain)

NASA Astrophysics Data System (ADS)

Marín, Ana Isabel; Mudarra, Matías; Andreo, Bartolomé

2016-04-01

Delineation of protection zones for water supply and implementation of proper land-use practices in surrounding areas are crucial aspects for a sustainable use of valuable drinking water resources. This is even more important in karst aquifers, which are particularly sensitive to contamination, having a very low self-cleaning capacity due to their structure and hydrological behavior. Consequently, specific methodologies adapted to the particular characteristics of karst media are necessary. In this work, an approach for protection zoning of the pilot site of Auta karst spring (southern Spain) is proposed, based on the application of COP+K method for contamination vulnerability and validation of results by natural (organic) tracers of infiltration (NO3-, TOC, intrinsic fluorescence) and by a dye tracer test conducted on June, 2011 (injecting 500 mg uranine). The aquifer drained by Auta spring (8.5 km2) presents a complex geological structure, formed by Jurassic dolostones and limestones highly folded and fractured. Recharge takes place by the infiltration of rainfall through karst landforms and also by losses in an adjacent river when it flows over the carbonate outcrops (dye injection point). Drainage is mainly through several springs located at the southwest, including Auta spring and 5 overflow springs. The source vulnerability map obtained by applying COP+K method can be adopted as the baseline to delineate the protection zones, through the conversion from vulnerability classes to degrees of protection. Dye tracer test and natural tracers of infiltration corroborate that aquifer sectors influenced by the river can be extremely vulnerable to pollution, but also well-developed exokarst features. In fact, slight evidences of pollution have been detected during the study period, with relatively-high NO3- contents and high fluorescence linked to bacteriological activity in Auta spring water. The jointly use of natural and artificial tracers constitute a reliable and effective procedure for validating vulnerability mapping of karst systems and springs used for water supply. This procedure is meant to implement and to complement protection zone mapping, particularly in countries lacking guidelines for protecting the water resources of karst aquifers.

Simple flow injection colorimetric system for determination of paraquat in natural water.

PubMed

Chuntib, Prakit; Jakmunee, Jaroon

2015-11-01

A simple and low cost flow injection colorimetric system has been developed for determination of paraquat in natural water. The developed method is based on the reduction of paraquat by using sodium dithionite as a reducing agent in an alkaline medium to produce a blue free radical ion that can be detected by a simple light emitting diode-light dependent resistor (LED-LDR) colorimeter. The standard or sample solution was injected via a set of 3-way solenoid valves into a water carrier stream and flowed to merge with reagent to generate a colored product which is proportional to the concentration of paraquat ion in the solution. Under the optimum condition of the system, i.e., mixing coil length 30 cm, flow rate 2.0 mL min(-1), sample volume 100 μL, concentrations of dithionite 0.1% (w/v) and sodium hydroxide 0.06 mol L(-1), a linear calibration graph in the range of 0.2-10.0 mg L(-1) with a correlation coefficient of 0.9996, and a limit of detection of 0.15 mg L(-1) were achieved. Relative standard deviation for 9 replicate injections of 1 mg L(-1) paraquat is 3.7%. A sample throughput of 40 injections h(-1) was achieved. The limit of detection can be improved by off-line preconcentration of paraquat employing a column packed with Dowex 50WX8-100 (H) cation exchange resin and eluted with 10% (w/v) ammonium chloride in ammonium buffer solution pH 10. The eluting solution was then injected into the FI system for paraquat determination. The proposed system did not suffer from interferences of some possible ions in natural water and other herbicides. Recoveries obtained by spiking 0.5 and 5.0 mg L(-1) paraquat standard into water samples were in the range of 104-110% and 101-105%, respectively. The developed system can be conveniently applied for screening of paraquat contaminated in natural water. Copyright © 2015 Elsevier B.V. All rights reserved.

Reducing Exposure to High Fluoride Drinking Water in Estonia—A Countrywide Study

PubMed Central

Indermitte, Ene; Saava, Astrid; Karro, Enn

2014-01-01

Fluoride is a naturally occurring contaminant in groundwater in Estonia. There are several regions in Estonia with fluoride contents in public water supplies as high as 7 mg/L. Long-term exposure to high-fluoride drinking water may have several adverse health effects, primarily dental fluorosis. The opportunities for exposure reduction rely highly on water treatment technologies. Since 2004 public water suppliers in Estonia have made efforts to diminish fluoride content in drinking water systems. A follow-up study on a country level was carried out in 2004–2012 to analyze the changes in population exposure to excessive (over 1.5 mg/L) fluoride in drinking water and to get information about the reduction methods applied by public water supplies (PWS) to optimize the fluoride levels in public water system. The results showed that bigger PWS have been more effective in fluoride reduction measures than small PWS. The main methods used to lower the fluoride content were reverse osmosis technology and replacement of water sources with new ones (new drilled wells). As a result of all the measures taken the overall high-fluoride exposure has been reduced substantially (82%). PMID:24637908

Simulation of Intra- or transboundary surface-water-rights hierarchies using the farm process for MODFLOW-2000

USGS Publications Warehouse

Schmid, W.; Hanson, R.T.

2007-01-01

Water-rights driven surface-water allocations for irrigated agriculture can be simulated using the farm process for MODFLOW-2000. This paper describes and develops a model, which simulates routed surface-water deliveries to farms limited by streamflow, equal-appropriation allotments, or a ranked prior-appropriation system. Simulated diversions account for deliveries to all farms along a canal according to their water-rights ranking and for conveyance losses and gains. Simulated minimum streamflow requirements on diversions help guarantee supplies to senior farms located on downstream diverting canals. Prior appropriation can be applied to individual farms or to groups of farms modeled as "virtual farms" representing irrigation districts, irrigated regions in transboundary settings, or natural vegetation habitats. The integrated approach of jointly simulating canal diversions, surface-water deliveries subject to water-rights constraints, and groundwater allocations is verified on numerical experiments based on a realistic, but hypothetical, system of ranked virtual farms. Results are discussed in light of transboundary water appropriation and demonstrate the approach's suitability for simulating effects of water-rights hierarchies represented by international treaties, interstate stream compacts, intrastate water rights, or ecological requirements. ?? 2007 ASCE.

Reducing exposure to high fluoride drinking water in Estonia-a countrywide study.

PubMed

Indermitte, Ene; Saava, Astrid; Karro, Enn

2014-03-14

Fluoride is a naturally occurring contaminant in groundwater in Estonia. There are several regions in Estonia with fluoride contents in public water supplies as high as 7 mg/L. Long-term exposure to high-fluoride drinking water may have several adverse health effects, primarily dental fluorosis. The opportunities for exposure reduction rely highly on water treatment technologies. Since 2004 public water suppliers in Estonia have made efforts to diminish fluoride content in drinking water systems. A follow-up study on a country level was carried out in 2004-2012 to analyze the changes in population exposure to excessive (over 1.5 mg/L) fluoride in drinking water and to get information about the reduction methods applied by public water supplies (PWS) to optimize the fluoride levels in public water system. The results showed that bigger PWS have been more effective in fluoride reduction measures than small PWS. The main methods used to lower the fluoride content were reverse osmosis technology and replacement of water sources with new ones (new drilled wells). As a result of all the measures taken the overall high-fluoride exposure has been reduced substantially (82%).

Historical contributions of phosphorus from natural and agricultural sources and implications for stream water quality, Cheney Reservoir watershed, south-central Kansas

USGS Publications Warehouse

Pope, Larry M.; Milligan, Chad R.; Mau, David Phillip

2002-01-01

An examination of soil cores collected from 43 nonagricultural coring sites in the Cheney Reservoir watershed of south-central Kansas was conducted by the U.S. Geological Survey in September 1999. The cores were collected as part of an ongoing cooperative study with the city of Wichita, Kansas. The 43 sites (mostly cemeteries) were thought to have total phosphorus concentrations in the soil that are representative of natural conditions (unaffected by human activity). The purpose of this report is to present the analysis and evaluation of these soil cores, to quantify the phosphorus contributions to Cheney Reservoir from natural and agricultural sources, and to provide estimates of stream-water-quality response to natural concentrations of total phosphorus in the soil. Analysis of soil cores from the 43 sites produced natural concentrations of total phosphorus that ranged from 74 to 539 milligrams per kilogram with a median concentration of 245 milligrams per kilogram in 2-inch soil cores and from 50 to 409 milligrams per kilogram with a median concentration of 166 milligrams per kilogram in 8-inch soil cores. Natural concentrations of total phosphorus in soil were statistically larger in samples from coring sites in the eastern half of the watershed than in samples from coring sites in the western half of the watershed. This result partly explains a previously determined west-to-east increase in total phosphorus yields in streams of the Cheney Reservoir watershed. A comparison of total phosphorus concentrations in soil under natural conditions to the historical mean total phosphorus concentration in agriculturally enriched bottom sediment in Cheney Reservoir indicated that agricultural activities within the watershed have increased total phosphorus concentrations in watershed soil that is transported in streams to about 2.9 times natural concentrations. Retention efficiencies for phosphorus and sediment historically transported to Cheney Reservoir were calculated at 92 and 99 percent, respectively. Most of the phosphorus was retained in bottom sediment. Sediment accumulation in Cheney Reservoir was less than reservoir design-life specifications on the basis of the age of the reservoir. Estimates of mean total phosphorus concentrations for selected streams in the Cheney Reservoir watershed under natural concentrations of total phosphorus in soil and a historic set of watershed conditions indicate that water from two of the five streamflow sampling sites would not meet the total phosphorus water-quality goal of 0.10 milligram per liter established by the Cheney Reservoir Watershed Task Force Committee. These results imply that the water-quality goal for total phosphorus in some streams of the watershed may not be met simply by reducing the amount of phosphorus applied. Instead, meeting the goal could involve a combination of approaches-for example, reducing the agricultural distribution of phosphorus and implementing changes in watershed activities to mitigate phosphorus movement to surface water.

Experimental study to the influences of rotational speed and blade shape on water vortex turbine performance

NASA Astrophysics Data System (ADS)

Kueh, T. C.; Beh, S. L.; Ooi, Y. S.; Rilling, D. G.

2017-04-01

Water vortex turbine utilizes the natural behaviour of water to form free surface vortex for energy extraction. This allows simple construction and ease of management on the whole water vortex power plant system. To our findings, the literature study specifically on water vortex turbine is inadequate and low efficiency was reported. Influences of operating speed and blade shape on turbine performance are the two parameters investigated in this study. Euler Turbomachinery Equation and velocity triangle are used in the improvement analysis. Two turbines with flat blades and curved blades are tested and compared. Both turbines show similar rotational speed at no load condition. This suggested that the circulation force of the water vortex has more dominant effect on the turbine rotational speed, compared to the turbine’s geometry. Flat-blades turbine showed maximum efficiency of 21.63% at 3.27 rad/s whereas curved-blades turbine showed 22.24% at 3.56 rad/s. When operating load is applied, the backward-leaning curve helps the turbine blades to reduce the disturbance on the water vortex, and hence provide a better performance.

Effect of natural gas exsolution on specific storage in a confined aquifer undergoing water level decline.

PubMed

Yager, R M; Fountain, J C

2001-01-01

The specific storage of a porous medium, a function of the compressibility of the aquifer material and the fluid within it, is essentially constant under normal hydrologic conditions. Gases dissolved in ground water can increase the effective specific storage of a confined aquifer, however, during water level declines. This causes a reduction in pore pressure that lowers the gas solubility and results in exsolution. The exsolved gas then displaces water from storage, and the specific storage increases because gas compressibility is typically much greater than that of water or aquifer material. This work describes the effective specific storage of a confined aquifer exsolving dissolved gas as a function of hydraulic head and the dimensionless Henry's law constant for the gas. This relation is applied in a transient simulation of ground water discharge from a confined aquifer system to a collapsed salt mine in the Genesee Valley in western New York. Results indicate that exsolution of gas significantly increased the effective specific storage in the aquifer system, thereby decreasing the water level drawdown.

Effect of natural gas exsolution on specific storage in a confined aquifer undergoing water level decline

USGS Publications Warehouse

Yager, R.M.; Fountain, J.C.

2001-01-01

The specific storage of a porous medium, a function of the compressibility of the aquifer material and the fluid within it, is essentially constant under normal hydrologic conditions. Gases dissolved in ground water can increase the effective specific storage of a confined aquifer, however, during water level declines. This causes a reduction in pore pressure that lowers the gas solubility and results in exsolution. The exsolved gas then displaces water from storage, and the specific storage increases because gas compressibility is typically much greater than that of water or aquifer material. This work describes the effective specific storage of a confined aquifer exsolving dissolved gas as a function of hydraulic head and the dimensionless Henry's law constant for the gas. This relation is applied in a transient simulation of ground water discharge from a confined aquifer system to a collapsed salt mine in the Genesee Valley in western New York. Results indicate that exsolution of gas significantly increased the effective specific storage in the aquifer system, thereby decreasing the water level drawdown.

Removal of estrogens through water disinfection processes and formation of by-products.

PubMed

Pereira, Renata Oliveira; Postigo, Cristina; de Alda, Miren López; Daniel, Luiz Antonio; Barceló, Damià

2011-02-01

Estrogens constitute a recognized group of environmental emerging contaminants which have been proven to induce estrogenic effects in aquatic organisms exposed to them. Low removal efficiency in wastewater treatment plants results in the presence of this type of contaminants in surface waters and also even in finished drinking water. This manuscript reviews the environmental occurrence of natural (estrone, estradiol and estriol) and synthetic (ethynyl estradiol) estrogens in different water matrices (waste, surface, ground and drinking water), and their removal mainly via chemical oxidative processes. Oxidative treatments have been observed to be very efficient in eliminating estrogens present in water; however, disinfection by-products (DBPs) are generated during the process. Characterization of these DBPs is essential to assess the risk that drinking water may potentially pose to human health since these DBPs may also have endocrine disrupting properties. This manuscript reviews the DBPs generated during oxidative processes identified so far in the literature and the estrogenicity generated by the characterized DBPs and/or by the applied disinfection technology. Copyright © 2010 Elsevier Ltd. All rights reserved.

Non-contact assessment of COD and turbidity concentrations in water using diffuse reflectance UV-Vis spectroscopy.

PubMed

Agustsson, Jon; Akermann, Oliver; Barry, D Andrew; Rossi, Luca

2014-08-01

Water contamination is an important environmental concern underlining the need for reliable real-time information on contaminant concentrations in natural waters. Here, a new non-contact UV-Vis spectroscopic approach for monitoring contaminants in water, and especially wastewater, is proposed. Diffuse reflectance UV-Vis spectroscopy was applied to measure simultaneously the chemical oxygen demand (COD) and turbidity (TUR) concentrations in water. The measurements were carried out in the wavelength range from 200-1100 nm. The measured spectra were analysed using partial-least-squares (PLS) regression. The correlation coefficient between the measured and the reference concentrations of COD and TUR in the water samples were R(2) = 0.85 and 0.96, respectively. These results highlight the potential of non-contact UV-Vis spectroscopy for the assessment of water contamination. A system built on the concept would be able to monitor wastewater pollution continuously, without the need for laborious sample collection and subsequent laboratory analysis. Furthermore, since no parts of the system are in contact with the wastewater stream the need for maintenance is minimised.

Anthropogenic water bodies as drought refuge for aquatic macroinvertebrates and macrophytes.

PubMed

Dodemaide, David T; Matthews, Ty G; Iervasi, Dion; Lester, Rebecca E

2018-03-01

Ecological research associated with the importance of refuges has tended to focus on natural rather than anthropogenic water bodies. The frequency of disturbances, including drought events, is predicted to increase in many regions worldwide due to human-induced climate change. More frequent disturbance will affect freshwater ecosystems by altering hydrologic regimes, water chemistry, available habitat and assemblage structure. Under this scenario, many aquatic biota are likely to rely on permanent water bodies as refuge, including anthropogenic water bodies. Here, macroinvertebrate and macrophyte assemblages from waste-water treatment and raw-water storages (i.e. untreated potable water) were compared with nearby natural water bodies during autumn and winter 2013. We expected macroinvertebrate and macrophyte assemblages in raw-water storages to be representative of natural water bodies, while waste-water treatment storages would not, due to degraded water quality. However, water quality in natural water bodies differed from raw-water storages but was similar to waste-water treatment storages. Macroinvertebrate patterns matched those of water quality, with no differences occurring between natural water bodies and waste-water treatment storages, but assemblages in raw-water storages differed from the other two water bodies. Unexpectedly, differences associated with raw-water storages were attributable to low abundances of several taxa. Macrophyte assemblages in raw-water storages were representative of natural water bodies, but were less diverse and abundant in, or absent from, waste-water treatment storages. No clear correlations existed between any habitat variables and macroinvertebrate assemblages but a significant correlation between macrophyte assemblages and habitat characteristics existed. Thus, there were similarities in both water quality and macroinvertebrate assemblages between natural water bodies and waste-water treatment storages, and similarities in macrophyte assemblages between raw-water storages and natural water bodies. These similarities illustrate that anthropogenic water storages support representative populations of some aquatic biota across the landscape, and thus, may provide important refuge following disturbance where dispersal capabilities allow. Copyright © 2017 Elsevier B.V. All rights reserved.

Prioritizing conservation potential of arid-land montane natural springs and associated riparian areas

USGS Publications Warehouse

Thompson, B.C.; Matusik-Rowan, P. L.; Boykin, K.G.

2002-01-01

Using inventory data and input from natural resource professionals, we developed a classification system that categorizes conservation potential for montane natural springs. This system contains 18 classes based on the presence of a riparian patch, wetland species, surface water, and evidence of human activity. We measured physical and biological components of 276 montane springs in the Oscura Mountains above 1450 m and the San Andres Mountains above 1300 m in southern New Mexico. Two of the 18 classes were not represented during the inventory, indicating the system applies to conditions beyond the montane springs in our study area. The class type observed most often (73 springs) had a riparian patch, perennial surface water, and human evidence. We assessed our system in relation to 13 other wetland and riparian classification systems regarding approach, area of applicability, intended users, validation, ease of use, and examination of system response. Our classification can be used to rapidly assess priority of conservation potential for isolated riparian sites, especially springs, in arid landscapes. We recommend (1) including this classification in conservation planning, (2) removing deleterious structures from high-priority sites, and (3) assessing efficiency and use of this classification scheme elsewhere. ?? 2002 Elsevier Science Ltd.

Web-Based Geospatial Tools to Address Hazard Mitigation, Natural Resource Management, and Other Societal Issues

USGS Publications Warehouse

Hearn,, Paul P.

2009-01-01

Federal, State, and local government agencies in the United States face a broad range of issues on a daily basis. Among these are natural hazard mitigation, homeland security, emergency response, economic and community development, water supply, and health and safety services. The U.S. Geological Survey (USGS) helps decision makers address these issues by providing natural hazard assessments, information on energy, mineral, water and biological resources, maps, and other geospatial information. Increasingly, decision makers at all levels are challenged not by the lack of information, but by the absence of effective tools to synthesize the large volume of data available, and to utilize the data to frame policy options in a straightforward and understandable manner. While geographic information system (GIS) technology has been widely applied to this end, systems with the necessary analytical power have been usable only by trained operators. The USGS is addressing the need for more accessible, manageable data tools by developing a suite of Web-based geospatial applications that will incorporate USGS and cooperating partner data into the decision making process for a variety of critical issues. Examples of Web-based geospatial tools being used to address societal issues follow.

Flood mapping from Sentinel-1 and Landsat-8 data: a case study from river Evros, Greece

NASA Astrophysics Data System (ADS)

Kyriou, Aggeliki; Nikolakopoulos, Konstantinos

2015-10-01

Floods are suddenly and temporary natural events, affecting areas which are not normally covered by water. The influence of floods plays a significant role both in society and the natural environment, therefore flood mapping is crucial. Remote sensing data can be used to develop flood map in an efficient and effective way. This work is focused on expansion of water bodies overtopping natural levees of the river Evros, invading the surroundings areas and converting them in flooded. Different techniques of flood mapping were used using data from active and passive remote sensing sensors like Sentinlel-1 and Landsat-8 respectively. Space borne pairs obtained from Sentinel-1 were processed in this study. Each pair included an image during the flood, which is called "crisis image" and another one before the event, which is called "archived image". Both images covering the same area were processed producing a map, which shows the spread of the flood. Multispectral data From Landsat-8 were also processed in order to detect and map the flooded areas. Different image processing techniques were applied and the results were compared to the respective results of the radar data processing.

Spatial vulnerability assessments by regression kriging

NASA Astrophysics Data System (ADS)

Pásztor, László; Laborczi, Annamária; Takács, Katalin; Szatmári, Gábor

2016-04-01

Two fairly different complex environmental phenomena, causing natural hazard were mapped based on a combined spatial inference approach. The behaviour is related to various environmental factors and the applied approach enables the inclusion of several, spatially exhaustive auxiliary variables that are available for mapping. Inland excess water (IEW) is an interrelated natural and human induced phenomenon causes several problems in the flat-land regions of Hungary, which cover nearly half of the country. The term 'inland excess water' refers to the occurrence of inundations outside the flood levee that originate from sources differing from flood overflow, it is surplus surface water forming due to the lack of runoff, insufficient absorption capability of soil or the upwelling of groundwater. There is a multiplicity of definitions, which indicate the complexity of processes that govern this phenomenon. Most of the definitions have a common part, namely, that inland excess water is temporary water inundation that occurs in flat-lands due to both precipitation and groundwater emerging on the surface as substantial sources. Radon gas is produced in the radioactive decay chain of uranium, which is an element that is naturally present in soils. Radon is transported mainly by diffusion and convection mechanisms through the soil depending mainly on soil physical and meteorological parameters and can enter and accumulate in the buildings. Health risk originating from indoor radon concentration attributed to natural factors is characterized by geogenic radon potential (GRP). In addition to geology and meteorology, physical soil properties play significant role in the determination of GRP. Identification of areas with high risk requires spatial modelling, that is mapping of specific natural hazards. In both cases external environmental factors determine the behaviour of the target process (occurrence/frequncy of IEW and grade of GRP respectively). Spatial auxiliary information representing IEW or GRP forming environmental factors were taken into account to support the spatial inference of the locally experienced IEW frequency and measured GRP values respectively. An efficient spatial prediction methodology was applied to construct reliable maps, namely regression kriging (RK) using spatially exhaustive auxiliary data on soil, geology, topography, land use and climate. RK divides the spatial inference into two parts. Firstly the deterministic component of the target variable is determined by a regression model. The residuals of the multiple linear regression analysis represent the spatially varying but dependent stochastic component, which are interpolated by kriging. The final map is the sum of the two component predictions. Application of RK also provides the possibility of inherent accuracy assessment. The resulting maps are characterized by global and local measures of its accuracy. Additionally the method enables interval estimation for spatial extension of the areas of predefined risk categories. All of these outputs provide useful contribution to spatial planning, action planning and decision making. Acknowledgement: Our work was partly supported by the Hungarian National Scientific Research Foundation (OTKA, Grant No. K105167).

Encapsulation of Natural Polyphenolic Compounds; a Review

PubMed Central

Munin, Aude; Edwards-Lévy, Florence

2011-01-01

Natural polyphenols are valuable compounds possessing scavenging properties towards radical oxygen species, and complexing properties towards proteins. These abilities make polyphenols interesting for the treatment of various diseases like inflammation or cancer, but also for anti-ageing purposes in cosmetic formulations, or for nutraceutical applications. Unfortunately, these properties are also responsible for a lack in long-term stability, making these natural compounds very sensitive to light and heat. Moreover, polyphenols often present a poor biodisponibility mainly due to low water solubility. Lastly, many of these molecules possess a very astringent and bitter taste, which limits their use in food or in oral medications. To circumvent these drawbacks, delivery systems have been developed, and among them, encapsulation would appear to be a promising approach. Many encapsulation methods are described in the literature, among which some have been successfully applied to plant polyphenols. In this review, after a general presentation of the large chemical family of plant polyphenols and of their main chemical and biological properties, encapsulation processes applied to polyphenols are classified into physical, physico-chemical, chemical methods, and other connected stabilization methods. After a brief description of each encapsulation process, their applications to polyphenol encapsulation for pharmaceutical, food or cosmetological purposes are presented. PMID:24309309

A tide prediction and tide height control system for laboratory mesocosms

PubMed Central

Long, Jeremy D.

2015-01-01

Experimental mesocosm studies of rocky shore and estuarine intertidal systems may benefit from the application of natural tide cycles to better replicate variation in immersion time, water depth, and attendant fluctuations in abiotic and edaphic conditions. Here we describe a stand-alone microcontroller tide prediction open-source software program, coupled with a mechanical tidal elevation control system, which allows continuous adjustment of aquarium water depths in synchrony with local tide cycles. We used this system to monitor the growth of Spartina foliosa marsh cordgrass and scale insect herbivores at three simulated shore elevations in laboratory mesocosms. Plant growth decreased with increasing shore elevation, while scale insect population growth on the plants was not strongly affected by immersion time. This system shows promise for a range of laboratory mesocosm studies where natural tide cycling could impact organism performance or behavior, while the tide prediction system could additionally be utilized in field experiments where treatments need to be applied at certain stages of the tide cycle. PMID:26623195

Impacts of turbidity on corals: The relative importance of light limitation and suspended sediments.

PubMed

Bessell-Browne, Pia; Negri, Andrew P; Fisher, Rebecca; Clode, Peta L; Duckworth, Alan; Jones, Ross

2017-04-15

As part of an investigation of the effects of water quality from dredging/natural resuspension on reefs, the effects of suspended sediment concentrations (SSCs) (0, 30, 100mgL -1 ) and light (~0, 1.1, 8.6molphotonsm -2 d -1 ) were examined alone and in combination, on the corals Acropora millepora, Montipora capricornis and Porites spp. over an extended (28d) period. No effects were observed at any sediment concentrations when applied alone. All corals in the lowest light treatments lost chlorophyll a and discoloured (bleached) after a week. Coral mortality only occurred in the two lowest light treatments and was higher when simultaneously exposed to elevated SSCs. Compared to water quality data collected during large dredging programs and natural resuspension events (and in the absence of sediment deposition as a cause-effect pathway) these data suggest the light reduction associated with turbidity poses a proportionally greater risk than effects of elevated SSCs alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

Humidity Effect on Nanoscale Electrochemistry in Solid Silver Ion Conductors and the Dual Nature of Its Locality

DOE PAGES

Yang, Sangmo; Strelcov, Evgheni; Paranthaman, Mariappan Parans; ...

2015-01-07

Scanning probe microscopy (SPM) is a powerful tool to investigate electrochemistry in nanoscale volumes. While most SPM-based studies have focused on reactions at the tip-surface junction, charge and mass conservation requires coupled and intrinsically non-local cathodic and anodic processes that can be significantly affected by ambient humidity. Here, we explore the role of water in both cathodic and anodic processes, associated charge transport, and topographic volume changes depending on the polarity of tip bias. The first-order reversal curve current-voltage technique combined with simultaneous detection of the sample topography, referred to as FORC-IVz, was applied to a silver solid ion conductor.more » We found that the protons generated from water affect silver ionic conduction, silver particle formation and dissolution, and mechanical integrity of the material. This work highlights the dual nature (simultaneously local and non-local) of electrochemical SPM studies, which should be considered for comprehensive understanding of nanoscale electrochemistry.« less

Obtaining natural-like flow releases in diverted river reaches from simple riparian benefit economic models.

PubMed

Perona, Paolo; Dürrenmatt, David J; Characklis, Gregory W

2013-03-30

We propose a theoretical river modeling framework for generating variable flow patterns in diverted-streams (i.e., no reservoir). Using a simple economic model and the principle of equal marginal utility in an inverse fashion we first quantify the benefit of the water that goes to the environment in relation to that of the anthropic activity. Then, we obtain exact expressions for optimal water allocation rules between the two competing uses, as well as the related statistical distributions. These rules are applied using both synthetic and observed streamflow data, to demonstrate that this approach may be useful in 1) generating more natural flow patterns in the river reach downstream of the diversion, thus reducing the ecodeficit; 2) obtaining a more enlightened economic interpretation of Minimum Flow Release (MFR) strategies, and; 3) comparing the long-term costs and benefits of variable versus MFR policies and showing the greater ecological sustainability of this new approach. Copyright © 2013 Elsevier Ltd. All rights reserved.

Humidity effect on nanoscale electrochemistry in solid silver ion conductors and the dual nature of its locality.

PubMed

Yang, Sang Mo; Strelcov, Evgheni; Paranthaman, M Parans; Tselev, Alexander; Noh, Tae Won; Kalinin, Sergei V

2015-02-11

Scanning probe microscopy (SPM) is a powerful tool to investigate electrochemistry in nanoscale volumes. While most SPM-based studies have focused on reactions at the tip-surface junction, charge and mass conservation requires coupled and intrinsically nonlocal cathodic and anodic processes that can be significantly affected by ambient humidity. Here, we explore the role of water in both cathodic and anodic processes, associated charge transport, and topographic volume changes depending on the polarity of tip bias. The first-order reversal curve current-voltage technique combined with simultaneous detection of the sample topography, referred to as FORC-IVz, was applied to a silver solid ion conductor. We found that the protons generated from water affect silver ionic conduction, silver particle formation and dissolution, and mechanical integrity of the material. This work highlights the dual nature (simultaneously local and nonlocal) of electrochemical SPM studies, which should be considered for comprehensive understanding of nanoscale electrochemistry.

Utilization of Drinking Water Treatment Slurry to Produce Aluminum Sulfate Coagulant.

PubMed

Fouad, Mahmoud M; Razek, Taha M A; Elgendy, Ahmed S

2017-02-01

  In Egypt, water treatment consumes about 365 000 tons of aluminum sulfate and produces more than 100 million tons of sludge per year. The common disposal system of sludge in Egypt is to discharge it into natural waterways. Toxicity of aluminum, environmental regulations and costs of chemicals used in water treatment and sludge treatment processes led to an evaluation of coagulant recovery and subsequent reuse. The present work aimed at aluminum recovery from sludge of El-Shiekh Zayd water treatment plant (WTP) to produce aluminum sulfate coagulant. Sludge was characterized and the effect of five variables was tested and the process efficiency was evaluated at different operating conditions. Maximum recovery is 94.2% at acid concentration 1.5 N, sludge weight 5 g, mixing speed 60 rpm, temperature 60 °C and leaching time 40 min. Then optimum conditions were applied to get maximum recovery for aluminum sulfate and compared to commercial coagulant on raw water of El-Shiekh Zayd (WTP).

Geochemical Signature of Natural Water Recharge in the Jungar Basin and Its Response to Climate.

PubMed

Zhu, Bingqi; Yu, Jingjie; Rioual, Patrick

2016-01-01

This paper analyzed the physico-chemical characteristics of natural waters in a drainage system of the Jungar Basin, northwestern China to identify chemical evolution and recharge mechanisms of natural waters in an arid environment. The waters studied are different in mineralization, but are typically carbonate rivers and alkaline in nature. No Cl-dominated water type occurs, indicating an early stage of water evolution. Regolith and geomorphological parameters controlling ground-surface temperature may play a large role in the geological evolution of the water. Three main morphological and hydrological units are reflected in water physico-chemistry. Climate influences the salinization of natural waters substantially. Direct recharge from seasonal snow and ice-melt water and infiltration of rain to the ground are significant recharge processes for natural waters, but recharge from potential deep groundwater may be less important. The enrichment of ions in lakes has been mainly caused by evaporation rather than through the quality change of the recharged water.

Contemporary changes of water resources, water and land use in Central Asia based on observations and modeling.

NASA Astrophysics Data System (ADS)

Shiklomanov, A. I.; Prousevitch, A.; Sokolik, I. N.; Lammers, R. B.

2015-12-01

Water is a key agent in Central Asia ultimately determining human well-being, food security, and economic development. There are complex interplays among the natural and anthropogenic drivers effecting the regional hydrological processes and water availability. Analysis of the data combined from regional censuses and remote sensing shows a decline in areas of arable and irrigated lands and a significant decrease in availability of arable and irrigated lands per capita across all Central Asian countries since the middle of 1990thas the result of post-Soviet transformation processes. This change could lead to considerable deterioration in food security and human system sustainability. The change of political situation in the region has also resulted in the escalated problems of water demand between countries in international river basins. We applied the University of New Hampshire - Water Balance Model - Transport from Anthropogenic and Natural Systems (WBM-TrANS) to understand the consequences of changes in climate, water and land use on regional hydrological processes and water availability. The model accounts for sub-pixel land cover types, glacier and snow-pack accumulation/melt across sub-pixel elevation bands, anthropogenic water use (e.g. domestic and industrial consumption, and irrigation for most of existing crop types), hydro-infrastructure for inter-basin water transfer and reservoir/dam regulations. A suite of historical climate re-analysis and temporal extrapolation of MIRCA-2000 crop structure datasets has been used in WBM-TrANS for this project. A preliminary analysis of the model simulations over the last 30 years has shown significant spatial and temporal changes in hydrology and water availability for crops and human across the region due to climatic and anthropogenic causes. We found that regional water availability is mostly impacted by changes in extents and efficiency of crop filed irrigation, especially in highly arid areas of Central Asia, changes in winter snow storage, and shifts in seasonality and intensity of glacier melt waters driven by climatic changes.

Transpiration Driven Hydrologic Transport in vegetated shallow water environments: Implications on Diel and Seasonal Soil Biogeochemical Processes and System Management

NASA Astrophysics Data System (ADS)

Bachand, P.; Bachand, S. M.; Fleck, J.; Anderson, F.

2011-12-01

Hydrology arguably plays the most important role in biogeochemical cycling of mercury in wetlands and other shallow aquatic systems. CFSTR, PFR and non-ideal reactor models are oftentimes currently used to hydrologically assess these systems and to account for the fate, transport and cycling of constituents of concern (COC) with systems assumed to be non-leaky and with diffusion dominating soil transport. Yet a number of results in the literature imply transpiration drives soil transport: transpiration into the root zone is in the range of 50 - 75% of ET seasonally; gaseous emissions from aquatic systems show a diel pattern that tracks diel ET patterns; in long detention time aquatic systems ET is the largest sink for applied surface waters; and non-reactive tracers when applied to surface waters can find themselves in the root zone and within plants. All these findings strongly suggest transpiration driven infiltration into the root zone, is a significant hydrologic pathway for constituents and is an important transport mechanism. This paper examines the annual water budget for four shallow aquatic land uses in the Yolo Bypass, California: rice, wild rice, fallowed fields and wetlands. Results indicate that differences in hydrology between the fields, particularly the temporal nature of transpiration, play a significant role in mercury transformations and transport. During the irrigation period, fallowed fields discharged 6 cm of surface water (15% applied water), rice fields 31 - 43 cm (27 - 31% applied water), and wild rice fields 16 - 39 cm (15 - 31% applied water). Evapotranspiration rates were in the range of 120 - 130 cm/y for all land uses (i.e. rice, wild rice, fallowed fields and seasonal wetlands) except for the permanent wetland which was about 1/3 higher at about 170 cm/y. During the summer, approximately 50% of the applied surface water was drawn into the root zone to meet transpiration demands. Based upon results from our water budget and utilizing modified Peclet No. calculations, we quantified the relative importance of upward diffusion from the sediments and downward advection from transpiration as hydrologic transport mechanisms in the root zone. Transpiration driven infiltration moves water past the diffusive zone within 1 - 2 days in this system during the summer months. With the waning seasons, evapotranspiration diminishes until by winter diffusion dominates throughout the entire root zone. This model has great implications on the analyses of soil biogeochemical process in the root zone of shallow aquatic systems. Downward advection is a major transport mechanism into the root zone of shallow flooded aquatic systems and provides an important physical mechanism that drives variability in the seasonal and diel storage; release and cycling of COCs; and the creation of both a physical and chemical barrierd to upward diffusion of soil-borne COCs into the water column. Models that do not account for root zone interactions may not be able to capture diel and seasonal differences. Moreover, these interactions may lead to unanticipated environmental consequences as a result of cultural practices.

Transboundary aquifers: conceptual models for development of international law.

PubMed

Eckstein, Yoram; Eckstein, Gabriel E

2005-01-01

More than one-half of the world's population is dependent on ground water for everyday uses such as drinking, cooking, and hygiene. In fact, it is the most extracted natural resource in the world. As a result of growing populations and expanding economies, many aquifers today are being depleted while others are being contaminated. Notwithstanding the world's considerable reliance on this resource, ground water resources have long received only secondary attention as compared to surface water, especially among legislatures and policymakers. Today, while there are hundreds of treaties governing transboundary rivers and lakes, there is only one international agreement that directly addresses a transboundary aquifer. Given that many of the aquifers on which humanity so heavily relies cross international borders, there is a considerable gap in the sound management, allocation, and protection of such resources. In order to prevent future disputes over transboundary aquifers and to maximize the beneficial use of this resource, international law must be clarified as it applies to transboundary ground water resources. Moreover, it must be defined with a firm basis in sound scientific understanding. In this paper we offer six conceptual models is which ground water resources can have transboudary consequences. The models are intended to help in assessing the applicability and scientific soundness of existing and proposed rules governing transboundary ground water resources. In addition, we consider the development of international law as it applies to ground water resources and make recommendations based on the models and principles of hydrogeology. The objective is the development of clear, logical, and science-based norms of state conducts as they relate to aquifers that traverse political boundaries.

A field method for measurement of infiltration

USGS Publications Warehouse

Johnson, A.I.

1963-01-01

The determination of infiltration--the downward entry of water into a soil (or sediment)--is receiving increasing attention in hydrologic studies because of the need for more quantitative data on all phases of the hydrologic cycle. A measure of infiltration, the infiltration rate, is usually determined in the field by flooding basins or furrows, sprinkling, or measuring water entry from cylinders (infiltrometer rings). Rates determined by ponding in large areas are considered most reliable, but the high cost usually dictates that infiltrometer rings, preferably 2 feet in diameter or larger, be used. The hydrology of subsurface materials is critical in the study of infiltration. The zone controlling the rate of infiltration is usually the least permeable zone. Many other factors affect infiltration rate--the sediment (soil) structure, the condition of the sediment surface, the distribution of soil moisture or soil- moisture tension, the chemical and physical nature of the sediments, the head of applied water, the depth to ground water, the chemical quality and the turbidity of the applied water, the temperature of the water and the sediments, the percentage of entrapped air in the sediments, the atmospheric pressure, the length of time of application of water, the biological activity in the sediments, and the type of equipment or method used. It is concluded that specific values of the infiltration rate for a particular type of sediment are probably nonexistent and that measured rates are primarily for comparative use. A standard field-test method for determining infiltration rates by means of single- or double-ring infiltrometers is described and the construction, installation, and operation of the infiltrometers are discussed in detail.

Imaging System Performance and Visibility as Affected by the Physical Environment

DTIC Science & Technology

2013-09-30

devoted to the topic of light propagation and imaging across the air-sea interface and within the surface boundary layer of natural water bodies...Zaneveld and Pegau (2003) was used to estimate the horizontal visibility of a black target, y: y = 4.8 / α, (2) where α is the...attenuation coefficient at 532 nm, was necessary for predictions of horizontal visibility of a black target. Equations (2) and (3) were applied to IOP data

Preliminary assessment of Eflows on Lucanian Rivers through IHA implementation

NASA Astrophysics Data System (ADS)

Greco, Michele; Martino, Giovanni

2016-04-01

According to the WFD, the ecological flow (Eflow) is assumed to be the hydrological regime consistent with the achievement of the environmental objectives of "good quality status" in natural surface water bodies. As well known, the hydrological regime of natural flow plays a primary and crucial role influencing the physical conditions of habitats, which in turn determines the biotic composition and sustainability of aquatic ecosystems. Furthermore, the simple assumption to supply a minimum instream during dry periods is not enough anymore in order to protect the river environment. The recent hydro-ecological knowledge provides that all flow components must be included as operational targets for water quantitative management from base flows (including low flows) to high and flood regimes in terms of magnitude, frequency, duration, timing and rate of change. Several conceptual and numerical codes have been developed and applied on different case studies in order to define common tools to be implemented for the Eflow assessment. In such a frame, the work deals with the application of the Indicators of Hydrologic Alteration methodology (IHA by TNC) to main Lucanian rivers to assess the ecological flow to be assumed in each monitoring cross section. The analyses have been carried on monthly discharge data derived through a simple rainfall-runoff applied at the basin scale and based on the precipitation measurements obtained by the regional rainfall gauge stations.

Degradation of microcystin-RR using boron-doped diamond electrode.

PubMed

Zhang, Chunyong; Fu, Degang; Gu, Zhongze

2009-12-30

Microcystins (MCs), produced by blue-green algae, are one of the most common naturally occurring toxins found in natural environment. The presence of MCs in drinking water sources poses a great threat to people's health. In this study, the degradation behavior of microcystin-RR on boron-doped diamond (BDD) electrode was investigated under galvanostatic conditions. Such parameters as reaction time, supporting electrolyte and applied current density were varied in order to determine their effects on this oxidation process. The experimental results revealed the suitability of electrochemical processes employing BDD electrode for removing MC-RR from the solution. However, the efficient removal of MC-RR only occurred in the presence of sodium chloride that acted as redox mediators and the reaction was mainly affected by the chloride concentration (c(NaCl)) and applied current density (I(appl)). Full and quick removal of 0.50 microg/ml MC-RR in solution was achieved when the operating conditions of c(NaCl) and I(appl) were 20mM and 46.3 mA/cm(2), or 35 mM and 18.2 mA/cm(2) respectively. The kinetics for MC-RR degradation followed a pesudo-first order reaction in most cases, indicating the process was under mass transfer control. As a result of its excellent performance, the BDD technology could be considered as a promising alternative to promote the degradation of MC-RR than chlorination in drinking water supplies.

Oyster Fisheries App

NASA Technical Reports Server (NTRS)

Perez Guerrero, Geraldo A.; Armstrong, Duane; Underwood, Lauren

2015-01-01

This project is creating a cloud-enabled, HTML 5 web application to help oyster fishermen and state agencies apply Earth science to improve the management of this important natural and economic resource. The Oyster Fisheries app gathers and analyzes environmental and water quality information, and alerts fishermen and resources managers about problems in oyster fishing waters. An intuitive interface based on Google Maps displays the geospatial information and provides familiar interactive controls to the users. Alerts can be tailored to notify users when conditions in specific leases or public fishing areas require attention. The app is hosted on the Amazon Web Services cloud. It is being developed and tested using some of the latest web development tools such as web components and Polymer.

Advancing drought monitoring using a Small Unmanned Aerial System (sUAS) in a changing climate

NASA Astrophysics Data System (ADS)

Ryu, J.

2016-12-01

Drought as a natural hazard, increasingly threatens the sustainability of regional water resources around the world. Given current trends in climate variability and change, droughts are likely to continue and increase. One of the effective ways to mitigate drought impacts may be to use a Small Unmanned Aerial System (sUAS) to improve understanding of the factors that drive the onset and development of drought conditions at local levels would enable planners and end users to more effectively manage and meter out limited water resources. During the presentation, the author will propose a methodological approach to apply sUAS for drought monitoring along with federal regulations and policies.

Seasonal Dynamics of Microcystis spp. and Their Toxigenicity as Assessed by qPCR in a Temperate Reservoir

PubMed Central

Martins, António; Moreira, Cristiana; Vale, Micaela; Freitas, Marisa; Regueiras, Ana; Antunes, Agostinho; Vasconcelos, Vitor

2011-01-01

Blooms of toxic cyanobacteria are becoming increasingly frequent, mainly due to water quality degradation. This work applied qPCR as a tool for early warning of microcystin(MC)-producer cyanobacteria and risk assessment of water supplies. Specific marker genes for cyanobacteria, Microcystis and MC-producing Microcystis, were quantified to determine the genotypic composition of the natural Microcystis population. Correlations between limnological parameters, pH, water temperature, dissolved oxygen and conductivity and MC concentrations as well as Microcystis abundance were assessed. A negative significant correlation was observed between toxic (with mcy genes) to non-toxic (without mcy genes) genotypes ratio and the overall Microcystis density. The highest proportions of toxic Microcystis genotypes were found 4–6 weeks before and 8–10 weeks after the peak of the bloom, with the lowest being observed at its peak. These results suggest positive selection of non-toxic genotypes under favorable environmental growth conditions. Significant positive correlations could be found between quantity of toxic genotypes and MC concentration, suggesting that the method applied can be useful to predict potential MC toxicity risk. No significant correlation was found between the limnological parameters measured and MC concentrations or toxic genotypes proportions indicating that other abiotic and biotic factors should be governing MC production and toxic genotypes dynamics. The qPCR method here applied is useful to rapidly estimate the potential toxicity of environmental samples and so, it may contribute to the more efficient management of water use in eutrophic systems. PMID:22072994

Effect of treated wastewater application on soil water repellency of sandy soil with olive trees and grass cover

NASA Astrophysics Data System (ADS)

Diamantis, V.; Ziogas, A.; Giougis, J.; Pliakas, F.; Diamantis, I.

2009-04-01

Soil water repellency has received significant attention due to water scarcity and increasing demand of irrigation water worldwide. The objective of this study was to examine the effects of treated wastewater application on soil water repellency of a repellent sandy soil with olive trees and grass cover. Secondary effluent from a municipal wastewater treatment plant was applied directly on the field on a 4×2 m plot. Freshwater and a mixture of freshwater:wastewater (1:1) were used in subsequent plots for comparison. A total of 62 water applications were performed between March 2006 and July 2008. The soil receiving the mixture of freshwater:wastewater exhibited the highest wettability. The soil water repellency after the first year of wastewater application decreased in the respective plot compared with the soil under natural conditions. The higher values of the WDPT were determined on the freshwater irrigated plot. The field-moist samples on all plots revealed high wettability because the moisture content of the soil was maintained above the critical soil water content. The results of this study reveal that short-term application of treated municipal wastewater does not induce soil water repellency.

Climate change influence on drinking water quality

NASA Astrophysics Data System (ADS)

Kovacs, Melinda Haydee; Ristoiu, Dumitru; Voica, Cezara; Moldovan, Zaharie

2013-11-01

Although it are quite well known the possible effects of climate changes on surface waters availability and their hydrological risks, their consequences on drinking water quality is not well defined yet. Disinfection agents (as Cl2, O3, etc.) or multiple combinations of them for water treatment and disinfection purposes are applied by water treatment plants at worldwide level. Unfortunately, besides the benefits of these processes were also highlighted some undesirable effects such as formation of several disinfection by-products (DBPs) after reaction of disinfection agent with natural organic matter (NOM) from water body. DBPs formation in drinking water, suspected to posses adverse health effects to humans are strongly regulated in our days. Thus, throughout this study kinetics experiments both the main physicochemical factors that influencing the quality of drinking waters were evaluated as well how they act through possible warming or the consequences of extreme events. Increasing water temperatures with 1 - 5 °C above its normal value has showed that NOMs are presented in higher amount which led to the need for greater amount of disinfectant agent (5 - 15 %). Increasing the amount of disinfecting agent resulted in the formation of DBPs in significantly higher concentrations (between 5 - 30 %).

Deriving Scaling Factors Using a Global Hydrological Model to Restore GRACE Total Water Storage Changes for China's Yangtze River Basin

NASA Technical Reports Server (NTRS)

Long, Di; Yang, Yuting; Yoshihide, Wada; Hong, Yang; Liang, Wei; Chen, Yaning; Yong, Bin; Hou, Aizhong; Wei, Jiangfeng; Chen, Lu

2015-01-01

This study used a global hydrological model (GHM), PCR-GLOBWB, which simulates surface water storage changes, natural and human induced groundwater storage changes, and the interactions between surface water and subsurface water, to generate scaling factors by mimicking low-pass filtering of GRACE signals. Signal losses in GRACE data were subsequently restored by the scaling factors from PCR-GLOBWB. Results indicate greater spatial heterogeneity in scaling factor from PCR-GLOBWB and CLM4.0 than that from GLDAS-1 Noah due to comprehensive simulation of surface and subsurface water storage changes for PCR-GLOBWB and CLM4.0. Filtered GRACE total water storage (TWS) changes applied with PCR-GLOBWB scaling factors show closer agreement with water budget estimates of TWS changes than those with scaling factors from other land surface models (LSMs) in China's Yangtze River basin. Results of this study develop a further understanding of the behavior of scaling factors from different LSMs or GHMs over hydrologically complex basins, and could be valuable in providing more accurate TWS changes for hydrological applications (e.g., monitoring drought and groundwater storage depletion) over regions where human-induced interactions between surface water and subsurface water are intensive.

Dynamical nexus of water supply, hydropower and environment based on the modeling of multiple socio-natural processes: from socio-hydrological perspective

NASA Astrophysics Data System (ADS)

Liu, D.; Wei, X.; Li, H. Y.; Lin, M.; Tian, F.; Huang, Q.

2017-12-01

In the socio-hydrological system, the ecological functions and environmental services, which are chosen to maintain, are determined by the preference of the society, which is making the trade-off among the values of riparian vegetation, fish, river landscape, water supply, hydropower, navigation and so on. As the society develops, the preference of the value will change and the ecological functions and environmental services which are chosen to maintain will change. The aim of the study is to focus on revealing the feedback relationship of water supply, hydropower and environment and the dynamical feedback mechanism at macro-scale, and to establish socio-hydrological evolution model of the watershed based on the modeling of multiple socio-natural processes. The study will aim at the Han River in China, analyze the impact of the water supply and hydropower on the ecology, hydrology and other environment elements, and study the effect on the water supply and hydropower to ensure the ecological and environmental water of the different level. Water supply and ecology are usually competitive. In some reservoirs, hydropower and ecology are synergic relationship while they are competitive in some reservoirs. The study will analyze the multiple mechanisms to implement the dynamical feedbacks of environment to hydropower, set up the quantitative relationship description of the feedback mechanisms, recognize the dominant processes in the feedback relationships of hydropower and environment and then analyze the positive and negative feedbacks in the feedback networks. The socio-hydrological evolution model at the watershed scale will be built and applied to simulate the long-term evolution processes of the watershed of the current situation. Dynamical nexus of water supply, hydropower and environment will be investigated.

Natural radioactivity in underground water from the Outer Carpathians in Poland with the use of nuclear spectrometry techniques.

PubMed

Walencik, A; Kozłowska, B; Dorda, J; Zipper, W

2010-01-01

The investigations of natural radioactivity in underground mineral water and spring water in health resorts in the Outer Carpathians were performed. Samples from 40 water springs were collected 3-4 times over a period of 10 years (1997-2007). In order to obtain necessary data, two different nuclear spectrometry techniques were applied: WinSpectral alphabeta 1414 liquid scintillation counter from Wallac and alpha-spectrometer 7401 VR from Canberra-Packard, USA with the silicon surface barrier detector. The activity concentrations of (222)Rn in the investigated samples varied from below 1 to 50 Bq/l. For radium isotopes the concentrations were in a range from below 10 to 490 mBq/l for (226)Ra and from 29 to 397 mBq/l for (228)Ra. The highest concentrations for both radium isotopes were obtained for medicinal water Zuber III from Krynica spa. The activity concentrations for uranium isotopes varied from below 0.5 to 16 mBq/l for (238)U and from below 0.5 to 162 mBq/l for (234)U with the highest values obtained for water Zuber IV. The highest annual effective dose arising from mainly radium isotopes was obtained for Zuber III water and was equal to 75 microSv/yr. Additionally, the annual effective doses due to (222)Rn consumed with water were also estimated. The isotopic ratios between isotopes originating from the same decay chain ((234)U/(238)U, (226)Ra/(238)U) and from different radioactive decay chains ((226)Ra/(228)Ra) were determined. The correlations between different isotopes were presented. Copyright 2009 Elsevier Ltd. All rights reserved.

Optimization of cloud point extraction and solid phase extraction methods for speciation of arsenic in natural water using multivariate technique.

PubMed

Baig, Jameel A; Kazi, Tasneem G; Shah, Abdul Q; Arain, Mohammad B; Afridi, Hassan I; Kandhro, Ghulam A; Khan, Sumaira

2009-09-28

The simple and rapid pre-concentration techniques viz. cloud point extraction (CPE) and solid phase extraction (SPE) were applied for the determination of As(3+) and total inorganic arsenic (iAs) in surface and ground water samples. The As(3+) was formed complex with ammonium pyrrolidinedithiocarbamate (APDC) and extracted by surfactant-rich phases in the non-ionic surfactant Triton X-114, after centrifugation the surfactant-rich phase was diluted with 0.1 mol L(-1) HNO(3) in methanol. While total iAs in water samples was adsorbed on titanium dioxide (TiO(2)); after centrifugation, the solid phase was prepared to be slurry for determination. The extracted As species were determined by electrothermal atomic absorption spectrometry. The multivariate strategy was applied to estimate the optimum values of experimental factors for the recovery of As(3+) and total iAs by CPE and SPE. The standard addition method was used to validate the optimized methods. The obtained result showed sufficient recoveries for As(3+) and iAs (>98.0%). The concentration factor in both cases was found to be 40.

Geomorphic reclmation of a coal refuse pile

NASA Astrophysics Data System (ADS)

Hopkinson, L. C.; Quaranta, J.

2017-12-01

Geomorphic reclamation is a technique that may offer opportunities to improve mine reclamation in Central Appalachia. The design approach is based on constructing a steady-state, mature landform condition and takes into account the long-term climatic conditions, soil types, terrain grade, and vegetation. Geomorphic reclamation has been applied successfully in semi-arid regions but has not yet been applied in Central Appalachia. This work describes a demonstration study where geomorphic landforming techniques are being applied to a coarse coal refuse pile in southern West Virginia, USA. The reclamation design includes four geomorphic watersheds that radially drain runoff from the pile. Each watershed has one central draining channel and incorporates compound slope profiles similarly to naturally eroded slopes. Planar slopes were also included to maintain the impacted area. The intent is to alter the hydrology to decrease water quality treatment costs. The excavation cut and fill volumes are comparable to those of more conventional refuse pile reclamation designs. If proven successful then this technique can be part of a cost-effective solution to improve water quality at active and future refuse facilities, abandoned mine lands, bond forfeiture sites, landfills, and major earthmoving activities within the region.

Performance and Mechanisms of Ultrafiltration Membrane Fouling Mitigation by Coupling Coagulation and Applied Electric Field in a Novel Electrocoagulation Membrane Reactor.

PubMed

Sun, Jingqiu; Hu, Chengzhi; Tong, Tiezheng; Zhao, Kai; Qu, Jiuhui; Liu, Huijuan; Elimelech, Menachem

2017-08-01

A novel electrocoagulation membrane reactor (ECMR) was developed, in which ultrafiltration (UF) membrane modules are placed between electrodes to improve effluent water quality and reduce membrane fouling. Experiments with feedwater containing clays (kaolinite) and natural organic matter (humic acid) revealed that the combined effect of coagulation and electric field mitigated membrane fouling in the ECMR, resulting in higher water flux than the conventional combination of electrocoagulation and UF in separate units (EC-UF). Higher current densities and weakly acidic pH in the EMCR favored faster generation of large flocs and effectively reduced membrane pore blocking. The hydraulic resistance of the formed cake layers on the membrane surface in ECMR was reduced due to an increase in cake layer porosity and polarity, induced by both coagulation and the applied electric field. The formation of a polarized cake layer was controlled by the applied current density and voltage, with cake layers formed under higher electric field strengths showing higher porosity and hydrophilicity. Compared to EC-UF, ECMR has a smaller footprint and could achieve significant energy savings due to improved fouling resistance and a more compact reactor design.

Sensitive trace enrichment of environmental andiandrogen vinclozolin from natural waters and sediment samples using hollow-fiber liquid-phase microextraction.

PubMed

Lambropoulou, Dimitra A; Albanis, Triantafyllos A

2004-12-17

The presence of vinclozolin in the environment as far as the endocrine disruption effects in biota are concerned has raised interest in the environmental fate of this compound. In this respect, the present study attempts to investigate the feasibility of applying a novel quantitative method, liquid-phase microextraction (LPME), so as to determine this environmental andiandrogen in environmental samples such as water and sediment samples. The technique involved the use of a small amount (3 microL) of organic solvent impregnated in a hollow fiber membrane, which was attached to the needle of a conventional GC syringe. The extracted samples were analyzed by gas chromatography coupled with electron-capture detection. Experimental LPME conditions such as extraction solvent, stirring rate, content of NaCl and pH were tested. Once LPME was optimized, the performance of the proposed technique was evaluated for the determination of vinclozolin in different types of natural water samples. The recovery of spiked water samples was from 80 to 99%. The procedure was adequate for quantification of vinclozolin in waters at levels of 0.010 to 50 microg/L (r> 0.994) with a detection limit of 0.001 microg/L (S/N= 3). Natural sediment samples from the Aliakmonas River area (Macedonia, Greece) spiked with the target andiandrogen compound were liquid-liquid extracted and analyzed by the methodology developed in this work. No significant interferences from the samples matrix were noticed, indicating that the reported methodology is an innovative tactic for sample preparation in sediment analysis, with a considerable improvement in the achieved detection limits. The results demonstrated that apart from analyte enrichment, the proposed LPME procedure also serves as clean-up method and could be successfully performed to determine trace amounts of vinclozolin in water and sediment samples.

New Center Links Earth, Space, and Information Sciences

NASA Astrophysics Data System (ADS)

Aswathanarayana, U.

2004-05-01

Broad-based geoscience instruction melding the Earth, space, and information technology sciences has been identified as an effective way to take advantage of the new jobs created by technological innovations in natural resources management. Based on this paradigm, the University of Hyderabad in India is developing a Centre of Earth and Space Sciences that will be linked to the university's super-computing facility. The proposed center will provide the basic science underpinnings for the Earth, space, and information technology sciences; develop new methodologies for the utilization of natural resources such as water, soils, sediments, minerals, and biota; mitigate the adverse consequences of natural hazards; and design innovative ways of incorporating scientific information into the legislative and administrative processes. For these reasons, the ethos and the innovatively designed management structure of the center would be of particular relevance to the developing countries. India holds 17% of the world's human population, and 30% of its farm animals, but only about 2% of the planet's water resources. Water will hence constitute the core concern of the center, because ecologically sustainable, socially equitable, and economically viable management of water resources of the country holds the key to the quality of life (drinking water, sanitation, and health), food security, and industrial development of the country. The center will be focused on interdisciplinary basic and pure applied research that is relevant to the practical needs of India as a developing country. These include, for example, climate prediction, since India is heavily dependent on the monsoon system, and satellite remote sensing of soil moisture, since agriculture is still a principal source of livelihood in India. The center will perform research and development in areas such as data assimilation and validation, and identification of new sensors to be mounted on the Indian meteorological satellites to make measurements in those spectral bands and with those polarizations that are needed to address water resources management issues.

Application of Hyperspectral Remote Sensing Techniques to Evaluate Water Quality in Turbid Coastal Waters of South Carolina.

NASA Astrophysics Data System (ADS)

Ali, K. A.; Ryan, K.

2014-12-01

Coastal and inland waters represent a diverse set of resources that support natural habitat and provide valuable ecosystem services to the human population. Conventional techniques to monitor water quality using in situ sensors and laboratory analysis of water samples can be very time- and cost-intensive. Alternatively, remote sensing techniques offer better spatial coverage and temporal resolution to accurately characterize the dynamic and unique water quality parameters. Existing remote sensing ocean color products, such as the water quality proxy chlorophyll-a, are based on ocean derived bio-optical models that are primarily calibrated in Case 1 type waters. These traditional models fail to work when applied in turbid (Case 2 type), coastal waters due to spectral interference from other associated color producing agents such as colored dissolved organic matter and suspended sediments. In this work, we introduce a novel technique for the predictive modeling of chlorophyll-a using a multivariate-based approach applied to in situ hyperspectral radiometric data collected from the coastal waters of Long Bay, South Carolina. This method uses a partial least-squares regression model to identify prominent wavelengths that are more sensitive to chlorophyll-a relative to other associated color-producing agents. The new model was able to explain 80% of the observed chlorophyll-a variability in Long Bay with RMSE = 2.03 μg/L. This approach capitalizes on the spectral advantage gained from current and future hyperspectral sensors, thus providing a more robust predicting model. This enhanced mode of water quality monitoring in marine environments will provide insight to point-sources and problem areas that may contribute to a decline in water quality. The utility of this tool is in its versatility to a diverse set of coastal waters and its use by coastal and fisheries managers with regard to recreation, regulation, economic and public health purposes.

Ocean foam generation and modeling

NASA Technical Reports Server (NTRS)

Porter, R. A.; Bechis, K. P.

1976-01-01

A laboratory investigation was conducted to determine the physical and microwave properties of ocean foam. Special foam generators were designed and fabricated, using porous glass sheets, known as glass frits, as the principal element. The glass frit was sealed into a water-tight vertical box, a few centimeters from the bottom. Compressed air, applied to the lower chamber, created ocean foam from sea water lying on the frit. Foam heights of 30 cm were readily achieved, with relatively low air pressures. Special photographic techniques and analytical procedures were employed to determine foam bubble size distributions. In addition, the percentage water content of ocean foam was determined with the aid of a particulate sampling procedure. A glass frit foam generator, with pore diameters in the range 70 - 100 micrometers, produced foam with bubble distributions very similar to those found on the surface of natural ocean foam patches.

Flotation-separation of aluminum from some water samples using powdered marble waste and oleic acid.

PubMed

Ghazy, Shaban el-Sayed; Samra, Salem el-Sayed; Mahdy, Abd el-Fattah Mohammed; el-Morsy, Sherin Mohammed

2003-10-01

Bench-scale experiments were conducted in the laboratory, aiming to remove aluminum from water. They were based on the use of powdered marble wastes (PMW), which are inexpensive and produced in large quantity, and thus potentially cause environmental problems, as an effective inorganic sorbent and oleic acid (HOL) as surfactant. The main parameters (solution pHs, sorbent, surfactant and aluminum concentrations, shaking time, ionic strength and the presence of foreign ions) that influence the sorptive-flotation process were examined. Good results were obtained under the optimum conditions, for which nearly 100% of aluminum at pH 7 and at room temperature (approximately 25 degrees C) was removed. The procedure was successfully applied to the recovery of aluminum spiked to some natural water samples. Moreover, a sorption and flotation mechanism is suggested.

Biased-probe-induced water ion injection into amorphous polymers investigated by electric force microscopy

NASA Astrophysics Data System (ADS)

Knorr, Nikolaus; Rosselli, Silvia; Miteva, Tzenka; Nelles, Gabriele

2009-06-01

Although charging of insulators by atomic force microscopy (AFM) has found widespread interest, often with data storage or nanoxerography in mind, less attention has been paid to the charging mechanism and the nature of the charge. Here we present a systematic study on charging of amorphous polymer films by voltage pulses applied to conducting AFM probes. We find a quadratic space charge limited current law of Kelvin probe force microscopy and electrostatic force microscopy peak volumes in pulse height, offset by a threshold voltage, and a power law in pulse width of positive exponents smaller than one. We interpret the results by a charging mechanism of injection and surface near accumulation of aqueous ions stemming from field induced water adsorption, with threshold voltages linked to the water affinities of the polymers.

Two-state thermodynamics and the possibility of a liquid-liquid phase transition in supercooled TIP4P/2005 water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Rakesh S.; Debenedetti, Pablo G.; Biddle, John W.

Water shows intriguing thermodynamic and dynamic anomalies in the supercooled liquid state. One possible explanation of the origin of these anomalies lies in the existence of a metastable liquid-liquid phase transition (LLPT) between two (high and low density) forms of water. While the anomalies are observed in experiments on bulk and confined water and by computer simulation studies of different water-like models, the existence of a LLPT in water is still debated. Unambiguous experimental proof of the existence of a LLPT in bulk supercooled water is hampered by fast ice nucleation which is a precursor of the hypothesized LLPT. Moreover,more » the hypothesized LLPT, being metastable, in principle cannot exist in the thermodynamic limit (infinite size, infinite time). Therefore, computer simulations of water models are crucial for exploring the possibility of the metastable LLPT and the nature of the anomalies. In this work, we present new simulation results in the NVT ensemble for one of the most accurate classical molecular models of water, TIP4P/2005. To describe the computed properties and explore the possibility of a LLPT, we have applied two-structure thermodynamics, viewing water as a non-ideal mixture of two interconvertible local structures (“states”). The results suggest the presence of a liquid-liquid critical point and are consistent with the existence of a LLPT in this model for the simulated length and time scales. We have compared the behavior of TIP4P/2005 with other popular water-like models, namely, mW and ST2, and with real water, all of which are well described by two-state thermodynamics. In view of the current debate involving different studies of TIP4P/2005, we discuss consequences of metastability and finite size in observing the liquid-liquid separation. We also address the relationship between the phenomenological order parameter of two-structure thermodynamics and the microscopic nature of the low-density structure.« less

Instrumentation and signal processing for the detection of heavy water using off axis-integrated cavity output spectroscopy technique

NASA Astrophysics Data System (ADS)

Gupta, A.; Singh, P. J.; Gaikwad, D. Y.; Udupa, D. V.; Topkar, A.; Sahoo, N. K.

2018-02-01

An experimental setup is developed for the trace level detection of heavy water (HDO) using the off axis-integrated cavity output spectroscopy technique. The absorption spectrum of water samples is recorded in the spectral range of 7190.7 cm-1-7191.5 cm-1 with the diode laser as the light source. From the recorded water vapor absorption spectrum, the heavy water concentration is determined from the HDO and water line. The effect of cavity gain nonlinearity with per pass absorption is studied. The signal processing and data fitting procedure is devised to obtain linear calibration curves by including nonlinear cavity gain effects into the calculation. Initial calibration of mirror reflectivity is performed by measurements on the natural water sample. The signal processing and data fitting method has been validated by the measurement of the HDO concentration in water samples over a wide range from 20 ppm to 2280 ppm showing a linear calibration curve. The average measurement time is about 30 s. The experimental technique presented in this paper could be applied for the development of a portable instrument for the fast measurement of water isotopic composition in heavy water plants and for the detection of heavy water leak in pressurized heavy water reactors.

Effects of toothbrushing with fluoride abrasive and whitening dentifrices on both unbleached and bleached human enamel surface in terms of roughness and hardness: an in vitro study.

PubMed

Bolay, Sukran; Cakir, Filiz Yalcin; Gurgan, Sevil

2012-09-01

The aim of this in vitro study was to evaluate the surface roughness and hardness of both unbleached and bleached (opalescence; 10% carbamide peroxide) human enamel brushed with water (without dentifrice), fluoride abrasive dentifrice (Colgate Total) and whitening dentifrice (Natural White). Human enamel samples were obtained from third molars and randomly divided into five groups (n = 8): G1 - Control (brushed with water without dentifrice), G2 - Colgate Total (fluoride abrasive dentifrice), G3 - Natural White (whitening dentifrice), G4 - Opalescence (10% carbamide peroxide) and then brushed with Colgate Total, G5 - Opalescence (10% carbamide peroxide) and then brushed with Natural White. Bleaching regimen was applied according to manufacturers' instructions. The brushing process was performed with a modified Nyffenegger's brushing machine. Surface roughness was analyzed with a profilometer. Microhardness testing was performed with a Brinell hardness tester. Results were statistically analyzed by Kruskal-Wallis, one-way ANOVA analysis and Mann-Whitney U, Wilcoxon matched-pairs signed-ranks tests. There were significant differences in surface roughness values for all groups, which showed an increase in roughness (p < 0.05). When the bleaching treatment combined with brushing with whitening dentifrice was performed (G5), there was a significant decrease in hardness values (p < 0.05). The other groups (G1, G2, G3, G4) showed no significant hardness differences (p > 0.05). It was concluded that toothbrushing procedures increased the enamel surface roughness, and that bleaching regimen performed with cleaning treatment, through brushing with whitening dentifrice decreased hardness values. When applied together, bleaching and cleaning treatments may alter the enamel surface roughness and hardness values.

Preservation of natural aquatic ecosystems by application of bottom coal ash based bioreactor for in situ treatment of anthropogenic effluents

NASA Astrophysics Data System (ADS)

Anker, Y.; Nisnevitch, M.; Tal, M.; Cahan, R.; Michael, E.

2012-12-01

One consequence of global climate change is recharge decrease at sub tropical and Mediterranean regions to both the surface and the ground fresh water resources. As a general rule, when water source quantity is reduced, the level of salination, as well as chemical and biological pollutants, tends to increase. The situation is more severe whenever the drainage basin is (a) heavily populated from urban, industrial and agricultural areas, (b) has wide areas of thin or non soil cover and (c) has a karstic structure and morphology. These latter conditions are typical to many regions around the Middle East; whereas pollution hazard to Mid Eastern streams is greater than to those in more humid regions owing to their relative small size and poor dilution capacity. The consequence of this ongoing and increasing anthropogenic pollution is endangerment of natural aquatic habitats and due to decrease in fresh water supply availability also to human sustainability. The ecological impact may involve transition of ephemeral (Wadi) streams into intermittent ones with the accompanied biodiversity change or extinction once the pollution is extreme. The impact on indigenous human communities might be as severe owing to drinking water quality decrease and the consequent decrease id quantity as well as damage to dryland farming. In setting of operations applied to the Yarkon Taninim watershed (central Israel) management, a pilot biofilter facility for sustainable preservation and rehabilitation of natural fluvial ecosystems was tested. This biofilter is planned to operate through low impact concept assimilating natural treatment processes occurring during runoff recharge through a porous flow media. The facility is constructed out of several grain sizes of bottom coal ash aggregate, which was found to be a better microbial mats growing stratum, compared to common natural aggregates such as tuff and lime pebbles (and also has an EPA directive for wastewater treatment). The biofilter is operating with initial horizontal flow and continuous vertical circulation through aeration apparatus. Along the flow path several different bio-modules are applied, the sequence consists of aerobic and anaerobic stages, as well as biomass preservation section and fine grain filtration. The pilot biofilter facility was built during the summer of 2009; the influent consisted of domestic wastewater (of the adjacent Ariel University dormitories) and also synthetic aquatic solutions equivalent to urban, industrial, and roads runoff effluents. The biofilter operation evaluation demonstrated significant decrease in pollution loads, including organic, salts and pathogens. The facility's efficiency reached approximately 90% reduction or more, allowing the release of treated runoff without limitation to natural fluvial ecosystems (according to the required regulations). The present stage in the project is implementation of the method and process by application of a full scale pilot facility at a joint between an anthropogenic drainage network, consisting of urban, industrial and motorway runoff collection systems and a typical natural Samaritan fluvial ecosystem. The purpose of the system is to treat these anthropogenic effluents prior to their release into the stream and by that to prevent the negative environmental above mentioned effects.

[Determination of biphenyl ether herbicides in water using HPLC with cloud-point extraction].

PubMed

He, Cheng-Yan; Li, Yuan-Qian; Wang, Shen-Jiao; Ouyang, Hua-Xue; Zheng, Bo

2010-01-01

To determine residues of multiple biphenyl ether herbicides simultaneously in water using high performance liquid chromatography (HPLC) with cloud-point extraction. The residues of eight biphenyl ether herbicides (including bentazone, fomesafen, acifluorfen, aclonifen, bifenox, fluoroglycofenethy, nitrofen, oxyfluorfen) in water samples were extracted with cloud-point extraction of Triton X-114. The analytes were separated and determined using reverse phase HPLC with ultraviolet detector at 300 nm. Optimized conditions for the pretreatment of water samples and the parameters of chromatographic separation applied. There was a good linear correlation between the concentration and the peak area of the analytes in the range of 0.05-2.00 mg/L (r = 0.9991-0.9998). Except bentazone, the spiked recoveries of the biphenyl ether herbicides in the water samples ranged from 80.1% to 100.9%, with relative standard deviations ranging from 2.70% to 6.40%. The detection limit of the method ranged from 0.10 microg/L to 0.50 microg/L. The proposed method is simple, rapid and sensitive, and can meet the requirements of determination of multiple biphenyl ether herbicides simultaneously in natural waters.

Assessing the impacts of climate change and socio-economic changes on flow and phosphorus flux in the Ganga river system.

PubMed

Jin, L; Whitehead, P G; Sarkar, S; Sinha, R; Futter, M N; Butterfield, D; Caesar, J; Crossman, J

2015-06-01

Anthropogenic climate change has impacted and will continue to impact the natural environment and people around the world. Increasing temperatures and altered rainfall patterns combined with socio-economic factors such as population changes, land use changes and water transfers will affect flows and nutrient fluxes in river systems. The Ganga river, one of the largest river systems in the world, supports approximately 10% global population and more than 700 cities. Changes in the Ganga river system are likely to have a significant impact on water availability, water quality, aquatic habitats and people. In order to investigate these potential changes on the flow and water quality of the Ganga river, a multi-branch version of INCA Phosphorus (INCA-P) model has been applied to the entire river system. The model is used to quantify the impacts from a changing climate, population growth, additional agricultural land, pollution control and water transfers for 2041-2060 and 2080-2099. The results provide valuable information about potential effects of different management strategies on catchment water quality.

Stability of fluctuating and transient aggregates of amphiphilic solutes in aqueous binary mixtures: Studies of dimethylsulfoxide, ethanol, and tert-butyl alcohol

NASA Astrophysics Data System (ADS)

Banerjee, Saikat; Bagchi, Biman

2013-10-01

In aqueous binary mixtures, amphiphilic solutes such as dimethylsulfoxide (DMSO), ethanol, tert-butyl alcohol (TBA), etc., are known to form aggregates (or large clusters) at small to intermediate solute concentrations. These aggregates are transient in nature. Although the system remains homogeneous on macroscopic length and time scales, the microheterogeneous aggregation may profoundly affect the properties of the mixture in several distinct ways, particularly if the survival times of the aggregates are longer than density relaxation times of the binary liquid. Here we propose a theoretical scheme to quantify the lifetime and thus the stability of these microheterogeneous clusters, and apply the scheme to calculate the same for water-ethanol, water-DMSO, and water-TBA mixtures. We show that the lifetime of these clusters can range from less than a picosecond (ps) for ethanol clusters to few tens of ps for DMSO and TBA clusters. This helps explaining the absence of a strong composition dependent anomaly in water-ethanol mixtures but the presence of the same in water-DMSO and water-TBA mixtures.

Distillation Designs for the Lunar Surface

NASA Technical Reports Server (NTRS)

Boul, Peter J.; Lange,Kevin E.; Conger, Bruce; Anderson, Molly

2010-01-01

Gravity-based distillation methods may be applied to the purification of wastewater on the lunar base. These solutions to water processing are robust physical separation techniques, which may be more advantageous than many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams.

Hypothetical Modeling of Redox Conditions Within a Complex Ground-Water Flow Field in a Glacial Setting

USGS Publications Warehouse

Feinstein, Daniel T.; Thomas, Mary Ann

2009-01-01

This report describes a modeling approach for studying how redox conditions evolve under the influence of a complex ground-water flow field. The distribution of redox conditions within a flow system is of interest because of the intrinsic susceptibility of an aquifer to redox-sensitive, naturally occurring contaminants - such as arsenic - as well as anthropogenic contaminants - such as chlorinated solvents. The MODFLOW-MT3D-RT3D suite of code was applied to a glacial valley-fill aquifer to demonstrate a method for testing the interaction of flow patterns, sources of reactive organic carbon, and availability of electron acceptors in controlling redox conditions. Modeling results show how three hypothetical distributions of organic carbon influence the development of redox conditions in a water-supply aquifer. The distribution of strongly reduced water depends on the balance between the rate of redox reactions and the capability of different parts of the flow system to transmit oxygenated water. The method can take account of changes in the flow system induced by pumping that result in a new distribution of reduced water.

Applied Use Value of Scientific Information for Management of Ecosystem Services

NASA Astrophysics Data System (ADS)

Raunikar, R. P.; Forney, W.; Bernknopf, R.; Mishra, S.

2012-12-01

The U.S. Geological Survey has developed and applied methods for quantifying the value of scientific information (VOI) that are based on the applied use value of the information. In particular the applied use value of U.S. Geological Survey information often includes efficient management of ecosystem services. The economic nature of U.S. Geological Survey scientific information is largely equivalent to that of any information, but we focus application of our VOI quantification methods on the information products provided freely to the public by the U.S. Geological Survey. We describe VOI economics in general and illustrate by referring to previous studies that use the evolving applied use value methods, which includes examples of the siting of landfills in Louden County, the mineral exploration efficiencies of finer resolution geologic maps in Canada, and improved agricultural production and groundwater protection in Eastern Iowa possible with Landsat moderate resolution satellite imagery. Finally, we describe the adaptation of the applied use value method to the case of streamgage information used to improve the efficiency of water markets in New Mexico.

Reef Development on Artificial Patch Reefs in Shallow Water of Panjang Island, Central Java

NASA Astrophysics Data System (ADS)

Munasik; Sugiyanto; Sugianto, Denny N.; Sabdono, Agus

2018-02-01

Reef restoration methods are generally developed by propagation of coral fragments, coral recruits and provide substrate for coral attachment using artificial reefs (ARs). ARs have been widely applied as a tool for reef restoration in degraded natural reefs. Successful of coral restoration is determined by reef development such as increasing coral biomass, natural of coral recruits and fauna associated. Artificial Patch Reefs (APRs) is designed by combined of artificial reefs and coral transplantation and constructed by modular circular structures in shape, were deployed from small boats by scuba divers, and are suitable near natural reefs for shallow water with low visibility of Panjang Island, Central Java. Branching corals of Acropora aspera, Montipora digitata and Porites cylindrica fragments were transplanted on to each module of two units of artificial patch reefs in different periods. Coral fragments of Acropora evolved high survival and high growth, Porites fragments have moderate survival and low growth, while fragment of Montipora show in low survival and moderate growth. Within 19 to 22 months of APRs deployment, scleractinian corals were recruited on the surface of artificial patch reef substrates. The most recruits abundant was Montastrea, followed by Poritids, Pocilloporids, and Acroporids. We conclude that artificial patch reefs with developed by coral fragments and natural coral recruitment is one of an alternative rehabilitation method in shallow reef with low visibility.

Application of natural resource valuation concepts for development of sustainable remediation plans for groundwater.

PubMed

Connor, John A; Paquette, Shawn; McHugh, Thomas; Gie, Elaine; Hemingway, Mark; Bianchi, Gino

2017-12-15

This paper explores the application of natural resource assessment and valuation procedures as a tool for developing groundwater remediation strategies that achieve the objectives for health and environmental protection, in balance with considerations of economic viability and conservation of natural resources. The natural resource assessment process, as applied under U.S. and international guidelines, entails characterization of groundwater contamination in terms of the pre-existing beneficial services of the impacted resource, the loss of these services caused by the contamination, and the measures and associated costs necessary to restore or replace the lost services. Under many regulatory programs, groundwater remediation objectives assume that the impacted groundwater may be used as a primary source of drinking water in the future, even if not presently in use. In combination with a regulatory preference for removal or treatment technologies, this assumed exposure, while protective of human health, can drive the remedy selection process toward remedies that may not be protective of the groundwater resource itself or of the other natural resources (energy, materials, chemicals, etc.) that may be consumed in the remediation effort. To achieve the same health and environmental protection goals under a sustainable remediation framework, natural resource assessment methods can be applied to restore the lost services and preserve the intact services of the groundwater so as to protect both current and future users of that resource. In this paper, we provide practical guidelines for use of natural resource assessment procedures in the remedy selection process and present a case study demonstrating the use of these protocols for development of sustainable remediation strategies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Assessment of 21st century drought conditions at Shasta Dam based on dynamically projected water supply conditions by a regional climate model coupled with a physically-based hydrology model.

PubMed

Trinh, T; Ishida, K; Kavvas, M L; Ercan, A; Carr, K

2017-05-15

Along with socioeconomic developments, and population increase, natural disasters around the world have recently increased the awareness of harmful impacts they cause. Among natural disasters, drought is of great interest to scientists due to the extraordinary diversity of their severity and duration. Motivated by the development of a potential approach to investigate future possible droughts in a probabilistic framework based on climate change projections, a methodology to consider thirteen future climate projections based on four emission scenarios to characterize droughts is presented. The proposed approach uses a regional climate model coupled with a physically-based hydrology model (Watershed Environmental Hydrology Hydro-Climate Model; WEHY-HCM) to generate thirteen equally likely future water supply projections. The water supply projections were compared to the current water demand for the detection of drought events and estimation of drought properties. The procedure was applied to Shasta Dam watershed to analyze drought conditions at the watershed outlet, Shasta Dam. The results suggest an increasing water scarcity at Shasta Dam with more severe and longer future drought events in some future scenarios. An important advantage of the proposed approach to the probabilistic analysis of future droughts is that it provides the drought properties of the 100-year and 200-year return periods without resorting to any extrapolation of the frequency curve. Copyright © 2017 Elsevier B.V. All rights reserved.

Detection and attribution of streamflow timing changes to climate change in the Western United States

USGS Publications Warehouse

Hidalgo, H.G.; Das, T.; Dettinger, M.D.; Cayan, D.R.; Pierce, D.W.; Barnett, T.P.; Bala, G.; Mirin, A.; Wood, A.W.; Bonfils, Celine; Santer, B.D.; Nozawa, T.

2009-01-01

This article applies formal detection and attribution techniques to investigate the nature of observed shifts in the timing of streamflow in the western United States. Previous studies have shown that the snow hydrology of the western United States has changed in the second half of the twentieth century. Such changes manifest themselves in the form of more rain and less snow, in reductions in the snow water contents, and in earlier snowmelt and associated advances in streamflow "center" timing (the day in the "water-year" on average when half the water-year flow at a point has passed). However, with one exception over a more limited domain, no other study has attempted to formally attribute these changes to anthropogenic increases of greenhouse gases in the atmosphere. Using the observations together with a set of global climate model simulations and a hydrologic model (applied to three major hydrological regions of the western United States_the California region, the upper Colorado River basin, and the Columbia River basin), it is found that the observed trends toward earlier "center" timing of snowmelt-driven streamflows in the western United States since 1950 are detectably different from natural variability (significant at the p < 0.05 level). Furthermore, the nonnatural parts of these changes can be attributed confidently to climate changes induced by anthropogenic greenhouse gases, aerosols, ozone, and land use. The signal from the Columbia dominates the analysis, and it is the only basin that showed a detectable signal when the analysis was performed on individual basins. It should be noted that although climate change is an important signal, other climatic processes have also contributed to the hydrologic variability of large basins in the western United States. ?? 2009 American Meteorological Society.

Approaches for derivation of environmental quality criteria for substances applied in risk assessment of discharges from offshore drilling operations.

PubMed

Altin, Dag; Frost, Tone Karin; Nilssen, Ingunn

2008-04-01

In order to achieve the offshore petroleum industries "zero harm" goal to the environment, the environmental impact factor for drilling discharges was developed as a tool to identify and quantify the environmental risks associated with disposal of drilling discharges to the marine environment. As an initial step in this work the main categories of substances associated with drilling discharges and assumed to contribute to toxic or nontoxic stress were identified and evaluated for inclusion in the risk assessment. The selection were based on the known toxicological properties of the substances, or the total amount discharged together with their potential for accumulation in the water column or sediments to levels that could be expected to cause toxic or nontoxic stress to the biota. Based on these criteria 3 categories of chemicals were identified for risk assessment the water column and sediments: Natural organic substances, metals, and drilling fluid chemicals. Several approaches for deriving the environmentally safe threshold concentrations as predicted no effect concentrations were evaluated in the process. For the water column consensus were reached for using the species sensitivity distribution approach for metals and the assessment factor approach for natural organic substances and added drilling chemicals. For the sediments the equilibrium partitioning approach was selected for all three categories of chemicals. The theoretically derived sediment quality criteria were compared to field-derived threshold effect values based on statistical approaches applied on sediment monitoring data from the Norwegian Continental Shelf. The basis for derivation of predicted no effect concentration values for drilling discharges should be consistent with the principles of environmental risk assessment as described in the Technical Guidance Document on Risk Assessment issued by the European Union.

Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

NASA Astrophysics Data System (ADS)

Jorgetto, A. O.; Silva, R. I. V.; Saeki, M. J.; Barbosa, R. C.; Martines, M. A. U.; Jorge, S. M. A.; Silva, A. C. P.; Schneider, J. F.; Castro, G. R.

2014-01-01

Through a series of simple processes, cassava root husks were turned into a fine powder of controlled particle size (63-75 μm). FTIR spectrum demonstrated the existence of alcohol, amine and carboxylic groups; and elemental analysis confirmed the presence of elements of interest such as sulphur, nitrogen and oxygen. Cross-polarized {1H}sbnd 13C NMR technique indicated the existence of methionine and thiamine through the signals observed at 55 ppm and 54 ppm, respectively, and the point of zero charge (pHpzc) was achieved at pH 5.2. The material was applied in solid-phase extraction of Cu(II) via batch experiments. Optimum adsorption pH was found to be in range of 3-6 and in the kinetic experiment the equilibrium was attained in 1 min. The highest adsorption capacity was 0.14 mmol g-1. The adsorption data were fit to the modified Langmuir equation, and the maximum amount of metal species extracted from the solution, Ns, was determined to be ∼0.14 mmol g-1, which is an indicative that the main adsorption mechanism is through chemisorption. Under optimized conditions, the material was utilized in preconcentration experiments, which culminated in an enrichment factor of 41.3-fold. With the aid of the enrichment factor, experiments were carried out to determine the Cu(II) content in tap water and natural water. Preconcentration method was also applied to a certified reference material (1643e) and the concentration found was 23.03 ± 0.79 μg L-1, whereas the specified Cu(II) concentration was 22.7 ± 0.31 μg L-1.

Enhanced hydrolysis and methane yield by applying microaeration pretreatment to the anaerobic co-digestion of brown water and food waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim, Jun Wei; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798; Wang, Jing-Yuan, E-mail: jywang@ntu.edu.sg

2013-04-15

Highlights: ► Microaeration pretreatment was effective for brown water and food waste mixture. ► The added oxygen was consumed fully by facultative microorganisms. ► Enhanced solubilization, acidification and breakdown of SCFAs to acetate. ► Microaeration pretreatment improved methane yield by 10–21%. ► Nature of inoculum influenced the effects of microaeration. - Abstract: Microaeration has been used conventionally for the desulphurization of biogas, and recently it was shown to be an alternative pretreatment to enhance hydrolysis of the anaerobic digestion (AD) process. Previous studies on microaeration pretreatment were limited to the study of substrates with complex organic matter, while little hasmore » been reported on its effect on substrates with higher biodegradability such as brown water and food waste. Due to the lack of consistent microaeration intensities, previous studies were not comparable and thus inconclusive in proving the effectiveness of microaeration to the overall AD process. In this study, the role of microaeration pretreatment in the anaerobic co-digestion of brown water and food waste was evaluated in batch-tests. After a 4-day pretreatment with 37.5 mL-O{sub 2}/L{sub R}-d added to the liquid phase of the reactor, the methane production of substrates were monitored in anaerobic conditions over the next 40 days. The added oxygen was consumed fully by facultative microorganisms and a reducing environment for organic matter degradation was maintained. Other than higher COD solubilization, microaeration pretreatment led to greater VFA accumulation and the conversion of other short chain fatty acids to acetate. This could be due to enhanced activities of hydrolytic and acidogenic bacteria and the degradation of slowly biodegradable compounds under microaerobic conditions. This study also found that the nature of inoculum influenced the effects of microaeration as a 21% and 10% increase in methane yield was observed when pretreatment was applied to inoculated substrates, and substrates without inoculum, respectively.« less

Estimation of deep infiltration in unsaturated limestone environments using cave lidar and drip count data

NASA Astrophysics Data System (ADS)

Mahmud, K.; Mariethoz, G.; Baker, A.; Treble, P. C.; Markowska, M.; McGuire, E.

2016-01-01

Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management, and for stalagmite-based paleoclimate reconstructions. Caves offer a natural inception point to observe both the long-term groundwater recharge and the preferential movement of water through the unsaturated zone of such limestone. With the availability of automated drip rate logging systems and remote sensing techniques, it is now possible to deploy the combination of these methods for larger-scale studies of infiltration processes within a cave. In this study, we utilize a spatial survey of automated cave drip monitoring in two large chambers of Golgotha Cave, south-western Western Australia (SWWA), with the aim of better understanding infiltration water movement and the relationship between infiltration, stalactite morphology, and unsaturated zone recharge. By applying morphological analysis of ceiling features from Terrestrial LiDAR (T-LiDAR) data, coupled with drip time series and climate data from 2012 to 2014, we demonstrate the nature of the relationships between infiltration through fractures in the limestone and unsaturated zone recharge. Similarities between drip rate time series are interpreted in terms of flow patterns, cave chamber morphology, and lithology. Moreover, we develop a new technique to estimate recharge in large-scale caves, engaging flow classification to determine the cave ceiling area covered by each flow category and drip data for the entire observation period, to calculate the total volume of cave discharge. This new technique can be applied to other cave sites to identify highly focussed areas of recharge and can help to better estimate the total recharge volume.

Estimation of deep infiltration in unsaturated limestone environments using cave LiDAR and drip count data

NASA Astrophysics Data System (ADS)

Mahmud, K.; Mariethoz, G.; Baker, A.; Treble, P. C.; Markowska, M.; McGuire, E.

2015-09-01

Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management and for stalagmite-based paleoclimate reconstructions. Caves offer a natural inception point to observe both the long-term groundwater recharge and the preferential movement of water through the unsaturated zone of such limestone. With the availability of automated drip rate logging systems and remote sensing techniques, it is now possible to deploy the combination of these methods for larger scale studies of infiltration processes within a cave. In this study, we utilize a spatial survey of automated cave drip monitoring in two large chambers of the Golgotha Cave, South-West Western Australia (SWWA), with the aim of better understanding infiltration water movement and the relationship between infiltration, stalactite morphology and unsaturated zone recharge. By applying morphological analysis of ceiling features from Terrestrial LiDAR (T-LiDAR) data, coupled with drip time series and climate data from 2012-2014, we demonstrate the nature of the relationships between infiltration through fractures in the limestone and unsaturated zone recharge. Similarities between drip-rate time series are interpreted in terms of flow patterns, cave chamber morphology and lithology. Moreover, we develop a new technique to estimate recharge in large scale caves, engaging flow classification to determine the cave ceiling area covered by each flow category and drip data for the entire observation period, to calculate the total volume of cave discharge. This new technique can be applied to other cave sites to identify highly focused areas of recharge and can help to better estimate the total recharge volume.

Trace determination of volatile polycyclic aromatic hydrocarbons in natural waters by magnetic ionic liquid-based stir bar dispersive liquid microextraction.

PubMed

Benedé, Juan L; Anderson, Jared L; Chisvert, Alberto

2018-01-01

In this work, a novel hybrid approach called stir bar dispersive liquid microextraction (SBDLME) that combines the advantages of stir bar sorptive extraction (SBSE) and dispersive liquid-liquid microextraction (DLLME) has been employed for the accurate and sensitive determination of ten polycyclic aromatic hydrocarbons (PAHs) in natural water samples. The extraction is carried out using a neodymium stir bar magnetically coated with a magnetic ionic liquid (MIL) as extraction device, in such a way that the MIL is dispersed into the solution at high stirring rates. Once the stirring is ceased, the MIL is magnetically retrieved onto the stir bar, and subsequently subjected to thermal desorption (TD) coupled to a gas chromatography-mass spectrometry (GC-MS) system. The main parameters involved in TD, as well as in the extraction step affecting the extraction efficiency (i.e., MIL amount, extraction time and ionic strength) were evaluated. Under the optimized conditions, the method was successfully validated showing good linearity, limits of detection and quantification in the low ng L -1 level, good intra- and inter-day repeatability (RSD < 13%) and good enrichment factors (18 - 717). This sensitive analytical method was applied to the determination of trace amounts of PAHs in three natural water samples (river, tap and rainwater) with satisfactory relative recovery values (84-115%), highlighting that the matrices under consideration do not affect the extraction process. Copyright © 2017 Elsevier B.V. All rights reserved.

DNA-tagged Microparticles for Tracing Water Flows and Travel Times in Natural Systems: The First results from Controlled Laboratory Experiments

NASA Astrophysics Data System (ADS)

Bogaard, T.; Bandyopadhyay, S.; Foppen, J. W.

2017-12-01

Societal demand for water safety is continuously increasing, being it resilient against flood/droughts, clean water for ecosystems, recreation or safe drinking water. Robust methods to measure temporal and spatial patterns of water and contaminant pathways are still lacking. Our research project aims to develop and apply (1) innovative, robust, and environmental-friendly silica-protected iron oxide micro-particles tagged with artificial DNA to trace contaminant movement and travel times of water in natural systems and (2) an innovative coupled model approach to capture dynamics in hydrological pathways and their effects on water quality. The exceptional property of DNA-tagging is the infinite number of unique tracers that can be produced and their detectability at extreme low concentrations. The advantage of the iron-core of the particle is the magnetic harvesting of the particles from water-samples. Such tracers are thought to give the water sector a unique tool for in-situ mapping of transport of contaminants and pathogenic microorganisms in water systems. However, the characteristics of the particle like magnetic property of the iron-core and surface potential of the silica layer, are of key importance for the behaviour of the particle in surface water and in soils. Furthermore, the application of such micro-particles requires strict protocols for the experiment, sampling and laboratory handling which are currently not available. We used two different types of silica-protected DNA-tagged micro-particles. We performed batch, column and flow experiments to assess the behaviour of the particles. We will present the first results of the controlled laboratory experiments for hydrological tracing. We will discuss the results and link it to the differences in particles design. Furthermore, we will draw conclusions and discuss knowledge gaps for future application of silica-protected DNA-tagged micro-particles in hydrological research.

Evaporation induced 18O and 13C enrichment in lake systems: A global perspective on hydrologic balance effects

NASA Astrophysics Data System (ADS)

Horton, Travis W.; Defliese, William F.; Tripati, Aradhna K.; Oze, Christopher

2016-01-01

Growing pressure on sustainable water resource allocation in the context of global development and rapid environmental change demands rigorous knowledge of how regional water cycles change through time. One of the most attractive and widely utilized approaches for gaining this knowledge is the analysis of lake carbonate stable isotopic compositions. However, endogenic carbonate archives are sensitive to a variety of natural processes and conditions leaving isotopic datasets largely underdetermined. As a consequence, isotopic researchers are often required to assume values for multiple parameters, including temperature of carbonate formation or lake water δ18O, in order to interpret changes in hydrologic conditions. Here, we review and analyze a global compilation of 57 lacustrine dual carbon and oxygen stable isotope records with a topical focus on the effects of shifting hydrologic balance on endogenic carbonate isotopic compositions. Through integration of multiple large datasets we show that lake carbonate δ18O values and the lake waters from which they are derived are often shifted by >+10‰ relative to source waters discharging into the lake. The global pattern of δ18O and δ13C covariation observed in >70% of the records studied and in several evaporation experiments demonstrates that isotopic fractionations associated with lake water evaporation cause the heavy carbon and oxygen isotope enrichments observed in most lakes and lake carbonate records. Modeled endogenic calcite compositions in isotopic equilibrium with lake source waters further demonstrate that evaporation effects can be extreme even in lake records where δ18O and δ13C covariation is absent. Aridisol pedogenic carbonates show similar isotopic responses to evaporation, and the relevance of evaporative modification to paleoclimatic and paleotopographic research using endogenic carbonate proxies are discussed. Recent advances in stable isotope research techniques present unprecedented opportunities to overcome the underdetermined nature of stable isotopic data through integration of multiple isotopic proxies, including dual element 13C-excess values and clumped isotope temperature estimates. We demonstrate the utility of applying these multi-proxy approaches to the interpretation of paleohydroclimatic conditions in ancient lake systems. Understanding past, present, and future hydroclimatic systems is a global imperative. Significant progress should be expected as these modern research techniques become more widely applied and integrated with traditional stable isotopic proxies.

Investigation of water seepage through porous media using X-ray imaging technique

NASA Astrophysics Data System (ADS)

Jung, Sung Yong; Lim, Seungmin; Lee, Sang Joon

2012-07-01

SummaryDynamic movement of wetting front and variation of water contents through three different porous media were investigated using X-ray radiography. Water and natural sand particles were used as liquid and porous media in this study. To minimize the effects of minor X-ray attenuation and uneven illumination, the flat field correction (FFC) was applied before determining the position of wetting front. In addition, the thickness-averaged (in the direction of the X-ray penetration) water content was obtained by employing the Beer-Lambert law. The initial inertia of water droplet influences more strongly on the vertical migration, compared to the horizontal migration. The effect of initial inertia on the horizontal migration is enhanced as sand size decreases. The pattern of water transport is observed to be significantly affected by the initial water contents. As the initial water contents increases, the bulb-type transport pattern is shifted to a trapezoidal shape. With increasing surface temperature, water droplets are easily broken on the sand surface. This consequently decreases the length of the initial inertia region. Different from the wetting front migration, the water contents at the initial stage clearly exhibit a preferential flow along the vertical direction. The water transport becomes nearly uniform in all directions beyond the saturation state.

Surface Water Detection Using Fused Synthetic Aperture Radar, Airborne LiDAR and Optical Imagery

NASA Astrophysics Data System (ADS)

Braun, A.; Irwin, K.; Beaulne, D.; Fotopoulos, G.; Lougheed, S. C.

2016-12-01

Each remote sensing technique has its unique set of strengths and weaknesses, but by combining techniques the classification accuracy can be increased. The goal of this project is to underline the strengths and weaknesses of Synthetic Aperture Radar (SAR), LiDAR and optical imagery data and highlight the opportunities where integration of the three data types can increase the accuracy of identifying water in a principally natural landscape. The study area is located at the Queen's University Biological Station, Ontario, Canada. TerraSAR-X (TSX) data was acquired between April and July 2016, consisting of four single polarization (HH) staring spotlight mode backscatter intensity images. Grey-level thresholding is used to extract surface water bodies, before identifying and masking zones of radar shadow and layover by using LiDAR elevation models to estimate the canopy height and applying simple geometry algorithms. The airborne LiDAR survey was conducted in June 2014, resulting in a discrete return dataset with a density of 1 point/m2. Radiometric calibration to correct for range and incidence angle is applied, before classifying the points as water or land based on corrected intensity, elevation, roughness, and intensity density. Panchromatic and multispectral (4-band) imagery from Quickbird was collected in September 2005 at spatial resolutions of 0.6m and 2.5m respectively. Pixel-based classification is applied to identify and distinguish water bodies from land. A classification system which inputs SAR-, LiDAR- and optically-derived water presence models in raster formats is developed to exploit the strengths and weaknesses of each technique. The total percentage of water detected in the sample area for SAR backscatter, LiDAR intensity, and optical imagery was 27%, 19% and 18% respectively. The output matrix of the classification system indicates that in over 72% of the study area all three methods agree on the classification. Analysis was specifically targeted towards areas where the methods disagree, highlighting how each technique should be properly weighted over these areas to increase the classification accuracy of water. The conclusions and techniques developed in this study are applicable to other areas where similar environmental conditions and data availability exist.

Sequential determination of multi-nutrient elements in natural water samples with a reverse flow injection system.

PubMed

Lin, Kunning; Ma, Jian; Yuan, Dongxing; Feng, Sichao; Su, Haitao; Huang, Yongming; Shangguan, Qipei

2017-05-15

An integrated system was developed for automatic and sequential determination of NO 2 - , NO 3 - , PO 4 3- , Fe 2+ , Fe 3+ and Mn 2+ in natural waters based on reverse flow injection analysis combined with spectrophotometric detection. The system operation was controlled by a single chip microcomputer and laboratory-programmed software written in LabVIEW. The experimental parameters for each nutrient element analysis were optimized based on a univariate experimental design, and interferences from common ions were evaluated. The upper limits of the linear range (along with detection limit, µmolL -1 ) of the proposed method was 20 (0.03), 200 (0.7), 12 (0.3), 5 (0.03), 5 (0.03), 9 (0.2) µmolL -1 , for NO 2 - , NO 3 - , PO 4 3- , Fe 2+ , Fe 3+ and Mn 2+ , respectively. The relative standard deviations were below 5% (n=9-13) and the recoveries varied from 88.0±1.0% to 104.5±1.0% for spiked water samples. The sample throughput was about 20h -1 . This system has been successfully applied for the determination of multi-nutrient elements in different kinds of water samples and showed good agreement with reference methods (slope 1.0260±0.0043, R 2 =0.9991, n=50). Copyright © 2017 Elsevier B.V. All rights reserved.

Chromatographic determination of nanomolar cyanate concentrations in estuarine and sea waters by precolumn fluorescence derivatization.

PubMed

Widner, Brittany; Mulholland, Margaret R; Mopper, Kenneth

2013-07-16

Recent studies suggest that cyanate (OCN(-)) is a potentially important source of reduced nitrogen (N) available to support the growth of aquatic microbes and, thus, may play a role in aquatic N cycling. However, aquatic OCN(-) distributions have not been previously described because of the lack of a suitable assay for measuring OCN(-) concentrations in natural waters. Previous methods were designed to quantify OCN(-) in aqueous samples with much higher reduced N concentrations (micromolar levels) than those likely to be found in natural waters (nanomolar levels). We have developed a method to quantify OCN(-) in dilute, saline environments. In the method described here, OCN(-) in aqueous solution reacts with 2-aminobenzoic acid to produce a highly fluorescent derivative, 2,4-quinazolinedione, which is then quantified using high performance liquid chromatography. Derivatization conditions were optimized to simultaneously minimize the reagent blank and maximize 2,4-quinazolinedione formation (>90% reaction yield) in estuarine and seawater matrices. A limit of detection (LOD) of 0.4 nM was achieved with only minor matrix effects. We applied this method to measure OCN(-) concentrations in estuarine and seawater samples from the Chesapeake Bay and coastal waters from the mid-Atlantic region. OCN(-) concentrations ranged from 0.9 to 41 nM. We determined that OCN(-) concentrations were stable in 0.2 μm filtered seawater samples stored at -80 °C for up to nine months.

On the Method of Efficient Ice Cold Energy Storage Using a Heat Transfer of Direct Contact Phase Change and a Natural Circulation of a Working Medium in an Enclosure

NASA Astrophysics Data System (ADS)

Utaka, Yoshio; Saito, Akio; Nakata, Naoki

The objectives of this report are to propose a new method of the high performance cold energy storage using ice as a phase change material and to clarify the heat transfer characteristics of the apparatus of ice cold energy storage based on the proposed principle. A working medium vapor layer a water layer and a working medium liquid layer stratified in this order from the top were kept in an enclosure composed of a condenser, an evaporator and a condensate receiver-and-return tube. The direct contact heat transfers between water or ice and a working medium in an enclosure were applied for realizing the high performance cold energy storage and release. In the storage and release processes, water changes the phase between the liquid and the solid, and the working medium cnanges between the vapor and the liquid with a natural circulation. Experimental apparatus was manufactured and R12 and R114 were selected as working media in the thermal energy storage enclosure. It was confirmed by the measurements that the efficient formation and melting of ice were achieved. Then, th e heat transfer characteristics were clarified for the effects of the initial water height, the initial height of woking medium liquid layer and the inlet coolant temperature.

The use of hydro-dynamic models in the practice-oriented education of engineering students

NASA Astrophysics Data System (ADS)

Sziebert, J.; Zellei, L.; Tamás, E. A.

2009-04-01

Management tasks related to open channel flows became rather comprehensive and multi-disciplinary, particularly with the predominancy of nature management aspects. The water regime of our rivers has proven to reach extremities more and more frequently in the past decades. In order to develop and analyse alternative solutions and to handle and resolve conflicts of interests, we apply 1D hydro-dynamic models in education for the explanation of processes and to improve practical skills of our students.

Process balance and product quality in the production of natural indigo from Polygonum tinctorium Ait. applying low-technology methods.

PubMed

Bechtold, T; Turcanu, A; Geissler, S; Ganglberger, E

2002-02-01

Indigo is the most important blue component in the class of natural dyes for cellulose and protein fibres. In the moderate European climate Polygonum tinctorium Ait. could be an interesting source for natural indigo (Vat blue 1). Following a cultivation of the plant material a simple procedure for the extraction of the indigo precursor indican was investigated with regard to crop and quality of dye obtained. The dependence of the crop on the storage conditions of the harvested plant material was investigated. The results quantify the distinct sensitivity of the fresh material to the time of storage before extraction with regard to the amount of natural indigo obtained, the photometrically determined indigo content in the product and the shade and colour depth observed in standardised dyeing experiments. A basic set of data is presented, which describes the process in terms of consumption of energy, water and chemicals and organic waste released from the extraction step.

Decision Support Model for Optimal Management of Coastal Gate

NASA Astrophysics Data System (ADS)

Ditthakit, Pakorn; Chittaladakorn, Suwatana

2010-05-01

The coastal areas are intensely settled by human beings owing to their fertility of natural resources. However, at present those areas are facing with water scarcity problems: inadequate water and poor water quality as a result of saltwater intrusion and inappropriate land-use management. To solve these problems, several measures have been exploited. The coastal gate construction is a structural measure widely performed in several countries. This manner requires the plan for suitably operating coastal gates. Coastal gate operation is a complicated task and usually concerns with the management of multiple purposes, which are generally conflicted one another. This paper delineates the methodology and used theories for developing decision support modeling for coastal gate operation scheduling. The developed model was based on coupling simulation and optimization model. The weighting optimization technique based on Differential Evolution (DE) was selected herein for solving multiple objective problems. The hydrodynamic and water quality models were repeatedly invoked during searching the optimal gate operations. In addition, two forecasting models:- Auto Regressive model (AR model) and Harmonic Analysis model (HA model) were applied for forecasting water levels and tide levels, respectively. To demonstrate the applicability of the developed model, it was applied to plan the operations for hypothetical system of Pak Phanang coastal gate system, located in Nakhon Si Thammarat province, southern part of Thailand. It was found that the proposed model could satisfyingly assist decision-makers for operating coastal gates under various environmental, ecological and hydraulic conditions.

Pharmaceutical Occurrence in Groundwater and Surface Waters in Forests Land-Applied with Municipal Wastewater

PubMed Central

McEachran, Andrew D.; Shea, Damian; Bodnar, Wanda; Nichols, Elizabeth Guthrie

2016-01-01

The occurrence and fate of pharmaceutical and personal care products in the environment are of increasing public importance because of their ubiquitous nature and documented effects on wildlife, ecosystems, and potentially humans. One potential, yet undefined, source of entry of pharmaceuticals into the environment is via the land application of municipal wastewater onto permitted lands. The objective of the present study is to determine the extent to which pharmaceuticals are mitigated by or exported from managed tree plantations irrigated with municipal wastewater. A specific focus of the present study is the presence of pharmaceutical compounds in groundwater and surface water discharge. The study site is a municipality that land-applies secondary treated wastewater onto 930 hectares of a 2000-hectare managed hardwood and pine plantation. A suite of 33 pharmaceuticals and steroid hormones was targeted in the analysis, which consisted of monthly grab sampling of groundwater, surface water, and wastewater, followed by concentration and cleanup via solid phase extraction and separation, detection, and quantification via liquid chromatography coupled with tandem mass spectrometry. More than one-half of all compounds detected in irrigated wastewater were not present in groundwater and subsequent surface water. However, antibiotics, nonsteroidal anti-inflammatory drugs, caffeine, and other prescription and over-the-counter drugs remained in groundwater and were transported into surface water at concentrations up to 10 ng/L. These results provide important documentation for pharmaceutical fate and transport in forest systems irrigated with municipal wastewater, a previously undocumented source of environmental entry. PMID:26297815

Molecular detection and characterization of noroviruses in river water in Thailand.

PubMed

Inoue, K; Motomura, K; Boonchan, M; Takeda, N; Ruchusatsawa, K; Guntapong, R; Tacharoenmuang, R; Sangkitporn, S; Chantaroj, S

2016-03-01

Norovirus (NoV) generally exists as a mixture of multiple genotype variants in nature. However, there has been no published report monitoring NoV in natural settings in Thailand. To obtain information on mixed presence of the NoV RNA genome, we conducted viral genome analysis of 15 water specimens collected from five sites in a river near Bangkok between August 2013 and August 2014. The number of viral RNA copies per specimen declined progressively from the most upstream to the most downstream site. Following direct nucleotide sequencing of the PCR products, we obtained three partial genome sequences of the NoV GI strain and 13 partial genome sequences of the NoV GII strains. Phylogenetic analysis indicated the presence of four GII.4 variant groups pro-circulated after the Den Haag_2006b, New Orleans_2009 and Sydney_2012 outbreaks. On the other hand, only GI.4 was observed from the specimens collected on April, 2014. These results indicated that multiple genogroups and genotypes of noroviruses are present and are circulating in the natural environment in Thailand as in other countries. Our study provides comprehensive information on the occurrence of new variants. Our study is the first paper that multiple genogroups and genotypes of norovirus exist, and are circulating in the river water near Bangkok, Thailand. Phylogenetic analysis indicated the presence of four GII.4 variant groups pro-circulated after the Den Haag_2006b, New Orleans_2009 and Sydney_2012 that caused outbreaks in the world. Continued research will be essential for understanding the natural history of NoV and the control of future outbreaks. © 2015 The Society for Applied Microbiology.

Trace analysis of 61 natural and synthetic progestins in river water and sewage effluents by ultra-high performance liquid chromatography-tandem mass spectrometry.

PubMed

Shen, Xiaoyan; Chang, Hong; Sun, Dezhi; Wang, Linxia; Wu, Fengchang

2018-04-15

A broad number of natural and synthetic progestins are widely used in human and veterinary therapies. Although progestins exhibit adverse effects in aquatic organisms, information about environmental occurrence and fate have been limited to several compounds, hampering the accuracy of risk assessments of the compounds. In this study, a selective and sensitive analytical method was established to simultaneously determine 19 natural and 42 synthetic progestins in environmental waters, and the synthetic progestins included 19-nortestosterone, 17α-hydroxyprogesterone and progesterone derivatives. All of the target compounds were effectively separated using an HSS T3 column, and the recoveries for effluent and river samples were 80-115% and 75-105%, respectively. The detection limits for the 61 analytes were in the range of 0.05-0.60 ng/L and 0.03-0.40 ng/L for the effluent and river samples, respectively. The developed method is applied to analyze the target progestogens in sewage effluent and river water samples from Beijing. The detected concentrations of natural progesterone metabolites (3α-hydroxy-5β-tetrahydroprogesterone) were up to 63 times higher than those of the parent compound. Of the three groups of synthetic progestins, the progesterone derivatives were detected for the first time and had the highest concentrations followed by the 19-nortestosterone and 17α-hydroxyprogesterone derivatives. In contrast to previous studies, the predominant derivative compounds of 19-nortestosterone were found to be 19-nortestosterone, gestodene and mifepristone, and those of 17α-hydroxyprogesterone were 6-epi-medroxy progesterone 17-acetate and melengestrol acetate. The toxicities and environmental risk of these emerging progestins deserves more attention in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Consensus Process at the Water Science and Technology Board, National Research Council

NASA Astrophysics Data System (ADS)

Logan, W. S.

2001-12-01

Whereas the very birth of the U.S. Geological Survey arose from the recommendations of a National Academy of Sciences report, water science has not always had a prominent place at that institution. Prior to the 1980s, water issues were dealt with on an ad hoc basis by various boards related to science, engineering, and policy. With the birth of the Water Science and Technology Board (WSTB) in 1982, a diversity of water-related issues are now handled under one roof. The "business" of the WSTB is to produce consensus reports on a spectrum of topics in water science. Some of the projects that the WSTB works on are self-generated. The majority are generated either by Congress, or by government agencies. The WSTB takes on several different kinds of studies. Some of these are designed to advance the science of hydrology itself. This category would include the report Opportunities in the Hydrologic Sciences, which helped to establish hydrologic science as something separate from applied hydrology in Congress, the White House, and agencies such as NSF. However, the majority of the board's consensus studies involve hydrology in the interests of improving the natural and human environment. For example, Water for the Future: The West Bank and Gaza Strip, Israel, and Jordan outlined consensus principles backed by scientists from all of these entities for sustaining freshwater resources of the region. Closer to home, but no less controversial, a WSTB committee recently reached consensus on improving the process by which states determine which water bodies are polluted enough to require clean-up, and develop Total Maximum Daily Loads for these pollutants. Another committee recently sorted through the scientific bases for using natural attenuation for various contaminants in ground water and soil. And an ongoing committee is trying to help the South Florida scientific community to determine the best strategies for restoring the Everglades to some semblance of its former self, while continuing to provide drinking and irrigation water and flood control. The committees and panels that we assemble meet over a period of months to years, and struggle to reach consensus on topics that by their very nature are problematical or controversial. Generally they succeed, by virtue of good will, strong leadership, and a well-defined statement of task.

Mobilization of selenium from the Mancos Shale and associated soils in the lower Uncompahgre River Basin, Colorado

USGS Publications Warehouse

Mast, M. Alisa; Mills, Taylor J.; Paschke, Suzanne S.; Keith, Gabrielle; Linard, Joshua I.

2014-01-01

This study investigates processes controlling mobilization of selenium in the lower part of the Uncompahgre River Basin in western Colorado. Selenium occurs naturally in the underlying Mancos Shale and is leached to groundwater and surface water by limited natural runoff, agricultural and domestic irrigation, and leakage from irrigation canals. Soil and sediment samples from the study area were tested using sequential extractions to identify the forms of selenium present in solid phases. Selenium speciation was characterized for nonirrigated and irrigated soils from an agricultural site and sediments from a wetland formed by a leaking canal. In nonirrigated areas, selenium was present in highly soluble sodium salts and gypsum. In irrigated soils, soluble forms of selenium were depleted and most selenium was associated with organic matter that was stable under near-surface weathering conditions. Laboratory leaching experiments and geochemical modeling confirm that selenium primarily is released to groundwater and surface water by dissolution of highly soluble selenium-bearing salts and gypsum present in soils and bedrock. Rates of selenium dissolution determined from column leachate experiments indicate that selenium is released most rapidly when water is applied to previously nonirrigated soils and sediment. High concentrations of extractable nitrate also were found in nonirrigated soils and bedrock that appear to be partially derived from weathered organic matter from the shale rather than from agricultural sources. Once selenium is mobilized, dissolved nitrate derived from natural sources appears to inhibit the reduction of dissolved selenium leading to elevated concentrations of selenium in groundwater. A conceptual model of selenium weathering is presented and used to explain seasonal variations in the surface-water chemistry of Loutzenhizer Arroyo, a major tributary contributor of selenium to the lower Uncompahgre River.

Aquatic fate of a double-stranded RNA in a sediment---water system following an over-water application.

PubMed

Fischer, Joshua R; Zapata, Fatima; Dubelman, Samuel; Mueller, Geoffrey M; Uffman, Joshua P; Jiang, Changjian; Jensen, Peter D; Levine, Steven L

2017-03-01

Determining the rate of biodegradation of double-stranded RNA (dsRNA) in the environment is an essential element of a comprehensive risk assessment of an RNA-based agricultural product. This information is used during problem formulation to define relevant routes and durations of environmental exposure for in planta-expressed dsRNA. Although exposure to biotechnology-derived crops expressing dsRNA traits in the aquatic environment is predicted to be minimal, little is known regarding the fate of dsRNA in these environments. To assess exposure to aquatic environments, a study was conducted to measure the rate of biodegradation of DvSnf7 dsRNA in aerobic water-sediment systems. Aquatic systems containing natural water and sediments that varied in physical and chemical characteristics were treated with dsRNA by applying DvSnf7 dsRNA directly to the water column. In the present study, DvSnf7 dsRNA dissipated rapidly from the water phase and was undetectable within 7 d as measured by QuantiGene (Affymetrix) and a sensitive insect bioassay in these diverse systems. Degradation kinetics estimated a half-life (time to 50% dissipation [DT50]) of less than 3 d and a time to 90% dissipation of approximately 4 d. Further analysis indicated that DvSnf7 dsRNA had DT50 values of less than 6 d in both sediment-free systems containing natural water and systems with only sediment. Taken together, the results of the present study indicate that dsRNA-based agricultural products rapidly degrade and consequently are unlikely to persist in aquatic environments. Environ Toxicol Chem 2017;36:727-734. © 2016 SETAC. © 2016 SETAC.

Integrated Modeling of the Human-Natural System to Improve Local Water Management and Planning

NASA Astrophysics Data System (ADS)

Gutowski, W. J., Jr.; Dziubanski, D.; Franz, K.; Goodwin, J.; Rehmann, C. R.; Simpkins, W. W.; Tesfastion, L.; Wanamaker, A. D.; Jie, Y.

2015-12-01

Communities across the world are experiencing the effects of unsustainable water management practices. Whether the problem is a lack of water, too much water, or water of degraded quality, finding acceptable solutions requires community-level efforts that integrate sound science with local needs and values. Our project develops both a software technology (agent-based hydrological modeling) and a social technology (a participatory approach to model development) that will allow communities to comprehensively address local water challenges. Using agent-based modeling (ABM), we are building a modeling system that includes a semi-distributed hydrologic process model coupled with agent (stakeholder) models. Information from the hydrologic model is conveyed to the agent models, which, along with economic information, determine appropriate agent actions that subsequently affect hydrology within the model. The iterative participatory modeling (IPM) process will assist with the continual development of the agent models. Further, IPM creates a learning environment in which all participants, including researchers, are co-exploring relevant data, possible scenarios and solutions, and viewpoints through continuous interactions. Our initial work focuses on the impact of flood mitigation and conservation efforts on reducing flooding in an urban area. We are applying all research elements above to the Squaw Creek watershed that flows through parts of four counties in central Iowa. The watershed offers many of the typical tensions encountered in Iowa, such as different perspectives on water management between upstream farmers and downstream urban areas, competition for various types of recreational services, and increasing absentee land ownership that may conflict with community values. Ultimately, climate change scenarios will be incorporated into the model to determine long term patterns that may develop within the social or natural system.

Monitoring Aquifer Depletion from Space: Case Studies from the Saharan and Arabian Aquifers

NASA Astrophysics Data System (ADS)

Ahmed, M.; Sultan, M.; Wahr, J. M.; Yan, E.

2013-12-01

Access to potable fresh water resources is a human right and a basic requirement for economic development in any society. In arid and semi-arid areas, the characterization and understanding of the geologic and hydrologic settings of, and the controlling factors affecting, these resources is gaining increasing importance due to the challenges posed by increasing population. In these areas, there is immense natural fossil fresh water resources stored in large extensive aquifers, the transboundary aquifers. Yet, natural phenomena (e.g., rainfall patterns and climate change) together with human-related factors (e.g., population growth, unsustainable over-exploitation, and pollution) are threatening the sustainability of these resources. In this study, we are developing and applying an integrated cost-effective approach to investigate the nature (i.e., natural and anthropogenic) and the controlling factors affecting the hydrologic settings of the Saharan (i.e., Nubian Sandstone Aquifer System [NSAS], Northwest Sahara Aquifer System [NWSA]) and Arabian (i.e., Arabian Peninsula Aquifer System [APAS]) aquifer systems. Analysis of the Gravity Recovery and Climate Experiment (GRACE)-derived Terrestrial Water Storage (TWS) inter-annual trends over the NSAS and the APAS revealed two areas of significant TWS depletions; the first correlated with the Dakhla Aquifer System (DAS) in the NSAS and second with the Saq Aquifer System (SAS) in the APAS. Annual depletion rates were estimated at 1.3 × 0.66 × 109 m3/yr and 6.95 × 0.68 × 109 m3/yr for DAS and SAS, respectively. Findings include (1) excessive groundwater extraction, not climatic changes, is responsible for the observed TWS depletions ;(2) the DAS could be consumed in 350 years if extraction rates continue to double every 50 years and the APAS available reserves could be consumed within 60-140 years at present extraction (7.08 × 109 m3/yr) and depletion rates; and (3) observed depletions over DAS and SAS and their absence across the remaining segments of the NSAS and the APAS suggest the aquifers are at near-steady conditions except for the DAS and SAS that are witnessing unsteady transient conditions. Implications for applying the methodologies advocated for assessment and optimum management of a large suite of fossil aquifers worldwide are clear.

The stable isotopes of site wide waters at an oil sands mine in northern Alberta, Canada

NASA Astrophysics Data System (ADS)

Baer, Thomas; Barbour, S. Lee; Gibson, John J.

2016-10-01

Oil sands mines have large disturbance footprints and contain a range of new landforms constructed from mine waste such as shale overburden and the byproducts of bitumen extraction such as sand and fluid fine tailings. Each of these landforms are a potential source of water and chemical release to adjacent surface and groundwater, and consequently, the development of methods to track water migration through these landforms is of importance. The stable isotopes of water (i.e. 2H and 18O) have been widely used in hydrology and hydrogeology to characterize surface water/groundwater interactions but have not been extensively applied in mining applications, or specifically to oil sands mining in northern Alberta. A prerequisite for applying these techniques is the establishment of a Local Meteoric Water Line (LMWL) to characterize precipitation at the mine sites as well as the development of a 'catalogue' of the stable water isotope signatures of various mine site waters. This study was undertaken at the Mildred Lake Mine Site, owned and operated by Syncrude Canada Ltd. The LMWL developed from 2 years (2009/2012) of sample collection is shown to be consistent with other LMWLs in western Canada. The results of the study highlight the unique stable water isotope signatures associated with hydraulically placed tailings (sand or fluid fine tailings) and overburden shale dumps relative to natural surface water and groundwater. The signature associated with the snow melt water on reclaimed landscapes was found to be similar to ground water recharge in the region. The isotopic composition of the shale overburden deposits are also distinct and consistent with observations made by other researchers in western Canada on undisturbed shales. The process water associated with the fine and coarse tailings streams has highly enriched 2H and 18O signatures. These signatures are developed through the non-equilibrium fractionation of imported fresh river water during evaporation from cooling towers used within the raw water process circuit. This highly fractionated surface water eventually becomes part of the recycled tailings water circuit, and as a consequence it undergoes further non-equilibrium fractionation as a result of surface evaporation, leading to additional enrichment along local evaporation lines.

DOE Office of Scientific and Technical Information (OSTI.GOV)

David C. Anderson, Lloyd T. Desotell, David B. Hudson, Gregory J. Shott, Vefa Yucel

Since January 2001, drainage lysimeter studies have been conducted at Yucca Flat, on the Nevada Test Site, in support of an evapotranspirative cover design. Yucca Flat has an arid climate with average precipitation of 16.5 cm annually. The facility consists of six drainage lysimeters 3 m in diameter, 2.4 m deep, and backfilled with a single layer of native soil. The bottom of each lysimeter is sealed and equipped with a small drain that enables direct measurement of saturated drainage. Each lysimeter has eight time-domain reflectometer probes to measure moisture content-depth profiles paired with eight heat-dissipation probes to measure soil-watermore » potential depth profiles. Sensors are connected to dataloggers which are remotely accessed via a phone line. The six lysimeters have three different surface treatments: two are bare-soil; two were revegetated with native species (primarily shadscale, winterfat, ephedra, and Indian rice grass); and two were allowed to revegetate naturally with such species as Russian thistle, halogeton, tumblemustard and cheatgrass. Beginning in October 2003, one half of the paired cover treatments (one bare soil, one invader species, and one native species) were irrigated with an amount of water equal to two times the natural precipitation to achieve a three times natural precipitation treatment. From October 2003 through December 2005, all lysimeters received 52.8 cm precipitation, and the four irrigated lysimeters received an extra 105.6 cm of irrigation. No drainage has occurred from any of the nonirrigated lysimeters, but moisture has accumulated at the bottom of the bare-soil lysimeter and the native-plant lysimeter. All irrigated lysimeters had some drainage. The irrigated baresoil lysimeter had 48.3 cm of drainage or 26.4 percent of the combined precipitation and applied irrigation for the entire monitoring record. The irrigated invader species lysimeter had 5.8 cm of drainage, about 3.2 percent of the combined precipitation and applied irrigation. An irrigation valve failure caused an additional 50.8 cm of irrigation to be applied to the irrigated native plant lysimeter. There has been 29.3 cm of drainage from this lysimeter, which is 11.5 percent of the total applied water. Approximately 40 percent of the drainage from the irrigated native plant lysimeter occurred within four weeks of the valve failure.« less

“Nanofiltration” Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples

NASA Astrophysics Data System (ADS)

Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R.

2016-02-01

Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation.

An estimate of human and natural contributions to changes in water resources in the upper reaches of the Minjiang River.

PubMed

Hou, Jingwen; Ye, Aizhong; You, Jinjun; Ma, Feng; Duan, Qingyun

2018-09-01

Climate change and human activities have changed the spatial-temporal distribution of water resources, especially in a fragile ecological area such as the upper reaches of the Minjiang River (UMR) basin, where they have had a more profound effect. The average of double-mass curve (DMC) and Distributed Time-Variant Gain Hydrological Model (DTVGM) are applied to distinguish between the impacts of climate change and human activities on water resources in this paper. Results indicated that water resources decreased over nearly 50 years in the UMR. At the annual scale, contributions of human activities and climate change to changes in discharge were -77% and 23%, respectively. In general, human activities decreased the availability of water resources, whereas climate change increased the availability of water resources. However, the impacts of human activities and climate change on water resources availability were distinctly different on annual versus seasonal scales, and they showed more inconsistency in summer and autumn. The main causes of decreasing water resources are reservoir regulation, and water use increases due to population growth. The results of this study can provide support for water resource management and sustainable development in the UMR basin. Copyright © 2018 Elsevier B.V. All rights reserved.

"Nanofiltration" Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples.

PubMed

Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R

2016-02-15

Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation.

“Nanofiltration” Enabled by Super-Absorbent Polymer Beads for Concentrating Microorganisms in Water Samples

PubMed Central

Xie, Xing; Bahnemann, Janina; Wang, Siwen; Yang, Yang; Hoffmann, Michael R.

2016-01-01

Detection and quantification of pathogens in water is critical for the protection of human health and for drinking water safety and security. When the pathogen concentrations are low, large sample volumes (several liters) are needed to achieve reliable quantitative results. However, most microbial identification methods utilize relatively small sample volumes. As a consequence, a concentration step is often required to detect pathogens in natural waters. Herein, we introduce a novel water sample concentration method based on superabsorbent polymer (SAP) beads. When SAP beads swell with water, small molecules can be sorbed within the beads, but larger particles are excluded and, thus, concentrated in the residual non-sorbed water. To illustrate this approach, millimeter-sized poly(acrylamide-co-itaconic acid) (P(AM-co-IA)) beads are synthesized and successfully applied to concentrate water samples containing two model microorganisms: Escherichia coli and bacteriophage MS2. Experimental results indicate that the size of the water channel within water swollen P(AM-co-IA) hydrogel beads is on the order of several nanometers. The millimeter size coupled with a negative surface charge of the beads are shown to be critical in order to achieve high levels of concentration. This new concentration procedure is very fast, effective, scalable, and low-cost with no need for complex instrumentation. PMID:26876979

Barometric fluctuations in wells tapping deep unconfined aquifers

USGS Publications Warehouse

Weeks, Edwin P.

1979-01-01

Water levels in wells screened only below the water table in unconfined aquifers fluctuate in response to atmospheric pressure changes. These fluctuations occur because the materials composing the unsaturated zone resist air movement and have capacity to store air with a change in pressure. Consequently, the translation of any pressure change at land surface is slowed as it moves through the unsaturated zone to the water table, but it reaches the water surface in the well instantaneously. Thus a pressure imbalance is created that results in a water level fluctuation. Barometric effects on water levels in unconfined aquifers can be computed by solution of the differential equation governing the flow of gas in the unsaturated zone subject to the appropriate boundary conditions. Solutions to this equation for two sets of boundary conditions were applied to compute water level response in a well tapping the Ogallala Formation near Lubbock, Texas from simultaneous microbarograph records. One set of computations, based on the step function unit response solution and convolution, resulted in a very good match between computed and measured water levels. A second set of computations, based on analysis of the amplitude ratios of simultaneous cyclic microbarograph and water level fluctuations, gave inconsistent results in terms of the unsaturated zone pneumatic properties but provided useful insights on the nature of unconfined-aquifer water level fluctuations.

Final report on CCQM-K70: Determination of Hg in natural water at a concentration level required by the European environmental quality standard (EQS)

NASA Astrophysics Data System (ADS)

Schiel, Detlef; Rienitz, Olaf

2011-01-01

This comparison 'Hg in natural water' was a follow-up to the pilot studies CCQM-P100.1 and CCQM-P100.2. The aim of this comparison was to demonstrate the capability of national metrology institutes to measure the Hg mass concentration in a natural water sample at the very low concentration level of γ(Hg) ≈ 70 ng/L as required by the EQS. In this way it served to help implement the European Water Framework Directive (WFD). This comparison was an activity of the Inorganic Analysis Working Group (IAWG) of CCQM and was piloted by Physikalisch-Technische Bundesanstalt (PTB, Braunschweig, Germany) with the help of the co-organizers Bundesanstalt für Materialforschung und -prüfung (BAM, Berlin, Germany), Laboratoire National de Métrologie et d'Essais (LNE, Paris, France), and the Joint Research Centre-Institute for Reference Materials and Measurements (EC-JRC-IRMM, Geel, Belgium). The following laboratories participated in this key comparison (in alphabetical order): BAM (Germany) EC-JRC-IRMM (European Union) KRISS (Republic of Korea) LGC (United Kingdom) LNE (France) NIST (United States of America) NMIA (Australia) NRC (Canada) PTB (Germany) SP (Sweden) The majority of participants applied isotope dilution mass spectrometry (IDMS) using sector field or quadrupole inductively coupled plasma MS (ICP-MS) in combination with cold vapour (CV) generation as the analytical technique. NRC reported a combined result of ID-CV-ICP-MS and CV atomic absorption spectrometry (CV-AAS). SP applied a standard addition method on a sector field ICP-MS, while BAM made use of an external 5-point calibration on a CV atomic fluorescence spectrometer (AFS). The key comparison reference value (KCRV) was agreed upon during the IAWG meeting in April 2010 at BIPM as the sum of the added Hg content calculated from the gravimetric sample preparation and the Hg matrix content of the water used for sample preparation (determined and validated on two independent pathways). Accordingly the degrees of equivalence were calculated. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Experimental response of Salix cuttings to sudden water table changing dynamics

NASA Astrophysics Data System (ADS)

Gorla, L.; Signarbieux, C.; Turberg, P.; Buttler, A.; Perona, P.

2013-12-01

Hydropower production, agriculture and other human activities change the natural flow regime of rivers, in turn impacting the riparian environment. Inadequate flow rules (e.g., minimal or residual flows) reflecting our limited understanding of eco-hydrological processes have thus been applied since decades. The main challenge for an eco-sustainable water management is to quantify the effects of flow regulation on channel morphodynamics and biological processes. We present a controlled laboratory experiment to investigate riparian vegetation (Salix Viminalis) response to forced water table changing dynamics, from one water regime to another, in a temperate region (Switzerland). Three synthetic flow regimes have been simulated and applied to three batteries of Salix cuttings (60 in total) growing outdoor within plastic pots, each about 1 meter tall. After an initial period where all pots undergone the same oscillations in order to uniform the plants initial conditions, the experiment started, and the water dynamic was changed for two out of three batteries. In particular, one treatment simulated a minimal flow policy, which drastically impacts the low and the medium-low components of the hydrograph, but not the extremes. The other treatment reproduced only the low frequencies corresponding to the seasonal trend of the natural flow regime, still applied on the third battery. Cuttings transitory response dynamics has been quantified by continuous sap flow and water potential measurements, and by regularly collecting growth parameters, as well as leaves photosynthesis, fluorescence, and pictures of each plant. At the end of the experiment, all cuttings were carefully removed and the both above and below ground biomass analyzed in detail. Particularly, the 3D root structure was obtained by High Resolution Computer Tomography. Our analyses reveal a clear dependence between roots distribution and water regime reflecting the need for adaptation, which are also in agreement with field observations of Pasquale et al. (2012, in press). In particular, an initial strong difference in terms of stress and growth performances was then followed by a later adjustment in the roots system, notably detected from tomographic images. Roots tropic response resulted in spatial reallocation, which likely allowed survivors to adapt to new conditions. Macroscopic effects in terms of growth parameters at weekly time step have found correspondence at higher time resolution in terms of sap flow and stem pressure, strengthening our results interpretation. Other interesting effects detected by sap flow meters and psychrometers in the transition time, even if coherent to water regimes, have not led to macroscopic effects. A discussion with data from a parallel field installation along the Thur River (Switzerland) is also made. REFERENCES - Pasquale et al., Effects of streamflow variability on the vertical root density distribution of willow cutting experiments, Ecological Engineering,2011, 10.1016/j.ecoleng.2012.12.002 - Pasquale et al., Above and below-ground Salix dynamics in response to river processes, Hydrological Processes., in press, 10.1002/hyp.9993

Effect of suppressor current intensity on the determination of glyphosate and aminomethylphosphonic acid by suppressed conductivity ion chromatography.

PubMed

Dimitrakopoulos, Ioannis K; Thomaidis, Nikolaos S; Megoulas, Nikolaos C; Koupparis, Michael A

2010-05-28

This paper presents the application of ion chromatography with electrolytic eluent generation and mobile phase suppression for the direct conductimetric detection of glyphosate and its degradation product aminomethylphosphonic acid (AMPA). The compounds were separated on a Dionex AS18 anion exchange column with a 12-40 mM KOH step gradient from 9 to 9.5 min. The effect of the suppressor current intensity on the electrostatic interaction of these amphoteric compounds with the suppressor cation exchange membranes was evaluated. A suppressor current gradient technique was proposed for the limitation of peak broadening and baseline noise, in order to improve method sensitivity and detectability. It was observed that residual sample carbonates co-eluted with AMPA when a large injection loop was installed for the low level determination of both compounds in natural waters. For this reason, glyphosate was isocratically eluted using 33 mM KOH in order to decrease analysis time within 10 min and a column clean up step using 100 mM KOH was used to ensure retention time reproducibility. The developed method was applied to the analysis of drinking and natural water and it was further successfully applied to orange samples with slight modifications. Instrumental LOD for glyphosate was 0.24 microg/L, while method LOD was 0.54 microg/L for spring waters and 0.01 mg/kg for oranges using a 1000 microL direct loop injection of the sample. Intra-day and inter-day precision (as %RSD) for water samples was 4.6% and 12% at a spiking level of 2 microg/L, and the recovery ranged from 64% to 88% depending on sample conductivity. For orange samples, the inter-day precision was 1.4% at a spiking level of 4.4 mg/kg, while overall recovery was 103%. The developed method is direct, fast, sensitive and relatively inexpensive, and could be used as an ideal fast screening tool for the monitoring of glyphosate residues in water and fruit samples. Copyright 2010 Elsevier B.V. All rights reserved.

Water Development: A Philosophical and Ethical Issue

NASA Astrophysics Data System (ADS)

Perkins, D.

2015-12-01

As one reviewer said about John McPhee's Encounters With the Archdruid:"So the real issues relate to what is natural? How should lands be used? What role do humans have in using, caring for, being part of the land and can we do so responsibly?" This quote applies equally to more than just land development -- it applies to water project too. Although Marc Reisner wrote Cadillac Desert in 1986, the lessons it presents about water development are current today. Not much has changed really in the past three decades. People still live in arid places where, perhaps, they should not live. Engineers still redesign nature to meet human needs, only to find out later that there are unintended consequences. About the only thing that has changed is that today the Bureau of Reclamation and other agencies do not spend megabucks to construct huge water projects. And, insignificant by comparison, some restoration and dam removal projects have begun on a limited scale. We developed an exercise, based on selected chapters from Reisner's book and a video derived from the book, to help students develop critical thinking and ethical reasoning skills. As we did so, we realized that there was much more that could be included. The ethical dilemmas associated with water development and related engineering projects are many. So, now, the original exercise has been expanded to 7 units. The original five units are based on Cadillac Desert. The sixth is based on a recent great documentary film, DamNation. The last unit is inspired by a terrific chapter from John McPhee's 1971 book Encounters with the Archdruid. The format is that student read articles and book chapters and then write responses to questions designed to get them to reflect on what they read. So, the exercises may be assigned as homework, but for the most value there must be some significant group discussions. If all units are used, this provides several weeks of homework for students, but instructors may cherry pick the units they wish to use. They pretty much stand alone - except that the last two tie everything together and call for more thought by the students.

Assessing water use and quality through youth participatory research in a rural Andean watershed.

PubMed

Roa García, C E; Brown, S

2009-07-01

Water availability, use and quality in a rural watershed of the Colombian Andes were investigated through participatory research involving local youth. Research included the quantification of disaggregated water use at the household level; comparison of water use with availability; monitoring water quality of streams, community water intakes and household faucets; and the determination of land use-water quality interactions. Youth were involved in all aspects of the research from design to implementation, dissemination of results and remediation options. Quantification of domestic and on-farm water use, and water availability indicated that water availability was sufficient during the study period, but that only an 8% decrease in dry season supply would result in shortages. Elevated conductivity levels in the headwaters were related to "natural" bank erosion, while downstream high conductivity and coliform levels were associated with discharges from livestock stalls and poorly maintained septic tanks in the stream buffer zone. Through the involvement of youth as co-investigators, the knowledge generated by the research was appropriated at the local level. Community workshops led by local youth promoted water conservation and water quality protection practices based on research, and resulted in broader community participation in water management. The approach involving youth in research stimulated improved management of both land and water resources, and could be applied in small rural watersheds in developed or developing countries.

Water Budget for the Island of Kauai, Hawaii

USGS Publications Warehouse

Shade, Patricia J.

1995-01-01

A geographic information system model was created to calculate a monthly water budget for the island of Kauai. Ground-water recharge is the residual component of a monthly water budget calculated using long-term average rainfall, streamflow, and pan-evaporation data, applied irrigation-water estimates, and soil characteristics. The water-budget components are defined seasonally, through the use of the monthly water budget, and spatially by aquifer-system areas, through the use of the geographic information system model. The mean annual islandwide water-budget totals are 2,720 Mgal/d for rainfall plus irrigation; 1,157 Mgal/d for direct runoff; 911 Mgal/d for actual evapotranspiration; and 652 Mgal/d for ground-water recharge. Direct runoff is 43 percent, actual evapotranspiration is 33 percent, and ground-water recharge is 24 percent of rainfall plus irrigation. Ground-water recharge in the natural land-use areas is spatially distributed in a pattern similar to the rainfall distribution. Distinct seasonal variations in the water-budget components are apparent from the monthly water-budget calculations. Rainfall and ground-water recharge peak during the wet winter months with highs in January of 3,698 Mgal/d (million gallons per day) and 981 Mgal/d, respectively; a slight peak in July and August relative to June and September is caused by increased orographic rainfall. Recharge is lowest in June (454 Mgal/d) and November (461 Mgal/d).

An integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes.

PubMed

Chiaradia, Enrico Antonio; Facchi, Arianna; Masseroni, Daniele; Ferrari, Daniele; Bischetti, Gian Battista; Gharsallah, Olfa; Cesari de Maria, Sandra; Rienzner, Michele; Naldi, Ezio; Romani, Marco; Gandolfi, Claudio

2015-09-01

The cultivation of rice, one of the most important staple crops worldwide, has very high water requirements. A variety of irrigation practices are applied, whose pros and cons, both in terms of water productivity and of their effects on the environment, are not completely understood yet. The continuous monitoring of irrigation and rainfall inputs, as well as of soil water dynamics, is a very important factor in the analysis of these practices. At the same time, however, it represents a challenging and costly task because of the complexity of the processes involved, of the difference in nature and magnitude of the driving variables and of the high variety of field conditions. In this paper, we present the prototype of an integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes. The system consists of the following: (1) flow measurement devices for the monitoring of irrigation supply and tailwater drainage; (2) piezometers for groundwater level monitoring; (3) level gauges for monitoring the flooding depth; (4) multilevel tensiometers and moisture sensor clusters to monitor soil water status; (5) eddy covariance station for the estimation of evapotranspiration fluxes and (6) wireless transmission devices and software interface for data transfer, storage and control from remote computer. The system is modular and it is replicable in different field conditions. It was successfully applied over a 2-year period in three experimental plots in Northern Italy, each one with a different water management strategy. In the paper, we present information concerning the different instruments selected, their interconnections and their integration in a common remote control scheme. We also provide considerations and figures on the material and labour costs of the installation and management of the system.

Optimizing magnetic nanoparticles for drinking water technology: The case of Cr(VI).

PubMed

Simeonidis, K; Kaprara, E; Samaras, T; Angelakeris, M; Pliatsikas, N; Vourlias, G; Mitrakas, M; Andritsos, N

2015-12-01

The potential of magnetite nanoparticles to be applied in drinking water treatment for the removal of hexavalent chromium is discussed. In this study, a method for their preparation which combines the use of low-cost iron sources (FeSO4 and Fe2(SO4)3) and a continuous flow mode, was developed. The produced magnetite nanoparticles with a size of around 20 nm, appeared relatively stable to passivation providing a removal capacity of 1.8 μg Cr(VI)/mg for a residual concentration of 50 μg/L when tested in natural water at pH7. Such efficiency is explained by the reducing ability of magnetite which turns Cr(VI) to an insoluble Cr(OH)3 form. The successful operation of a small-scale system consisting of a contact reactor and a magnetic separator demonstrates a way for the practical introduction and recovery of magnetite nanoparticles in water treatment technology. Copyright © 2015 Elsevier B.V. All rights reserved.

Observations of Highly Variable Deuterium in the Martian Upper Atmosphere

NASA Astrophysics Data System (ADS)

Clarke, John T.; Mayyasi-Matta, Majd A.; Bhattacharyya, Dolon; Chaufray, Jean-Yves; Chaffin, Michael S.; Deighan, Justin; Schneider, Nicholas M.; Jain, Sonal; Jakosky, Bruce

2017-10-01

One of the key pieces of evidence for historic high levels of water on Mars is the present elevated ratio of deuterium/hydrogen (D/H) in near-surface water. This can be explained by the loss of large amounts of water into space, with the lighter H atoms escaping faster than D atoms. Understanding the specific physical processes and controlling factors behind the present escape of H and D is the key objective of the MAVEN IUVS echelle channel. This knowledge can then be applied to an accurate extrapolation back in time to understand the water history of Mars. Observations of D in the martian upper atmosphere over the first martian year of the MAVEN mission have shown highly variable amounts of D, with a short-lived maximum just after perihelion and during southern summer. The timing and nature of this increase provide constraints on its possible origin. These results will be presented and compared with other measurements of the upper atmosphere of Mars.

Methane flux from the central Amazonian floodplain

NASA Technical Reports Server (NTRS)

Bartlett, Karen B.; Crill, Patrick M.; Sebacher, Daniel I.; Harriss, Robert C.; Wilson, John O.

1988-01-01

A total of 186 methane measurements from the three primary Amazon floodplain environments of open water lakes, flood forests, and floating grass mats were made over the period 18 July through 2 September 1985. These data indicate that emissions were lowest over open water lakes. Flux from flooded forests and grass mats was significantly higher. At least three transport processes contribute to tropospheric emissions: ebullition from sediments, diffusion along the concentration gradient from sediment to overlaying water to air, and transport through the roots and stems of aquatic plants. Measurements indicate that the first two of these processes are most significant. It was estimated that on the average bubbling makes up 49 percent of the flux from open water, 54 percent of that from flooded forests, and 64 percent of that from floating mats. If the measurements were applied to the entire Amazonian floodplain, it is calculated that the region could supply up to 12 percent of the estimated global natural sources of methane.

Removal of Lead from Water Using Calcium Alginate Beads Doped with Hydrazine Sulphate-Activated Red Mud as Adsorbent

PubMed Central

2017-01-01

Calcium alginate beads doped with hydrazine sulphate-treated red mud are investigated as adsorbent for extracting lead ions from water using batch methods of extraction. Different extraction conditions are optimised for maximum lead extraction. Substantial amount of lead is removed, and the adsorption ability is found to be 138.6 mg/g. Surface characterization using FTIR, EDX, and FESEM confirms that lead is “onto” the surface of the adsorbent. Thermodynamic parameters, adsorption isotherms, and kinetics of adsorption are analysed. Adsorption is “physisorption” in nature and spontaneous. The adsorbent developed can be regenerated using 0.1 M HCl. Thus regenerated adsorbent can be used as the adsorbent for further removal of lead at least 10 times, and this enables the complete removal of lead from water by repetitive use of the regenerated adsorbent. The beads facilitate the easy filtration. The methodology developed is successfully applied for removing lead from industrial waste waters. PMID:29527385

Adsorption of phospholipids at oil/water interfaces during emulsification is controlled by stress relaxation and diffusion.

PubMed

Hildebrandt, Ellen; Nirschl, Hermann; Kok, Robbert Jan; Leneweit, Gero

2018-05-16

Adsorption of phosphatidylcholines at oil/water interfaces strongly deviates from spread monolayers at air/water surfaces. Understanding its nature and consequences could vastly improve applications in medical nanoemulsions and biotechnologies. Adsorption kinetics at interfaces of water with different oil phases were measured by profile analysis tensiometry. Adsorption kinetics for 2 different phospholipids, DPPC and POPC, as well as 2 organic phases, squalene and squalane, show that formation of interfacial monolayers is initially dominated by stress-relaxation in the first minutes. Diffusion only gradually contributes to a decrease in interfacial tension at later stages of time and higher film pressures. The results can be applied for the optimization of emulsification protocols using mechanical treatments. Emulsions using phospholipids with unsaturated fatty acids are dominated much more strongly by stress-relaxation and cover interfaces very fast compared to those with saturated fatty acids. In contrast, phospholipid layers consisting of saturated fatty acids converge faster towards the equilibrium than those with unsaturated fatty acids.

Automated processing for proton spectroscopic imaging using water reference deconvolution.

PubMed

Maudsley, A A; Wu, Z; Meyerhoff, D J; Weiner, M W

1994-06-01

Automated formation of MR spectroscopic images (MRSI) is necessary before routine application of these methods is possible for in vivo studies; however, this task is complicated by the presence of spatially dependent instrumental distortions and the complex nature of the MR spectrum. A data processing method is presented for completely automated formation of in vivo proton spectroscopic images, and applied for analysis of human brain metabolites. This procedure uses the water reference deconvolution method (G. A. Morris, J. Magn. Reson. 80, 547(1988)) to correct for line shape distortions caused by instrumental and sample characteristics, followed by parametric spectral analysis. Results for automated image formation were found to compare favorably with operator dependent spectral integration methods. While the water reference deconvolution processing was found to provide good correction of spatially dependent resonance frequency shifts, it was found to be susceptible to errors for correction of line shape distortions. These occur due to differences between the water reference and the metabolite distributions.

Development and application of a catchment scale pesticide fate and transport model for use in drinking water risk assessment.

PubMed

Pullan, S P; Whelan, M J; Rettino, J; Filby, K; Eyre, S; Holman, I P

2016-09-01

This paper describes the development and application of IMPT (Integrated Model for Pesticide Transport), a parameter-efficient tool for predicting diffuse-source pesticide concentrations in surface waters used for drinking water supply. The model was applied to a small UK headwater catchment with high frequency (8h) pesticide monitoring data and to five larger catchments (479-1653km(2)) with sampling approximately every 14days. Model performance was good for predictions of both flow (Nash Sutcliffe Efficiency generally >0.59 and PBIAS <10%) and pesticide concentrations, although low sampling frequency in the larger catchments is likely to mask the true episodic nature of exposure. The computational efficiency of the model, along with the fact that most of its parameters can be derived from existing national soil property data mean that it can be used to rapidly predict pesticide exposure in multiple surface water resources to support operational and strategic risk assessments. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Jack D. Fellows: Congressional Science Fellow

NASA Astrophysics Data System (ADS)

Jack D. Fellows has been selected as the 1983-84 AGU Congressional Science Fellow. Last week he began his 1-year stint on Capitol Hill as AGU's seventh Congressional Science Fellow.Fellows received his Ph.D. earlier this year from the civil engineering department at the University of Maryland, College Park. For his dissertation he developed a management system using regional geographic information for hydrologic models. His work applied remote sensing data to the decision-making processes of regional planning organizations concerned with hydrology and natural resource management. The Maryland National Capital Park and Planning Commission has integrated Fellows' work into their programs on water resource and environmental planning; his approach also is being used for forest and water resource planning near Freiburg, Baden-Wurtemberg, West Germany.

Analysis of one dimension migration law from rainfall runoff on urban roof

NASA Astrophysics Data System (ADS)

Weiwei, Chen

2017-08-01

Research was taken on the hydrology and water quality process in the natural rain condition and water samples were collected and analyzed. The pollutant were included SS, COD and TN. Based on the mass balance principle, one dimension migration model was built for the rainfall runoff pollution in surface. The difference equation was developed according to the finite difference method, by applying the Newton iteration method for solving it. The simulated pollutant concentration process was in consistent with the measured value on model, and Nash-Sutcliffe coefficient was higher than 0.80. The model had better practicability, which provided evidence for effectively utilizing urban rainfall resource, non-point source pollution of making management technologies and measures, sponge city construction, and so on.

Effect of lubricant environment on saw damage in silicon wafers

NASA Technical Reports Server (NTRS)

Kuan, T. S.; Shih, K. K.; Vanvechten, J. A.; Westdorp, W. A.

1982-01-01

The chemomechanical effect of lubricant environments on the inner diameter (ID) sawing induced surface damage in Si wafers was tested for four different lubricants: water, dielectric oil, and two commercial cutting solutions. The effects of applying different potential on Si crystals during the sawing were also tested. It is indicated that the number and depth of surface damage are sensitive to the chemical nature of the saw lubricant. It is determined that the lubricants that are good catalysts for breaking Si bonds can dampen the out of plane blade vibration more effectively and produce less surface damage. Correlations between the applied potential and the depth of damage in the dielectric oil and one of the commercial cutting solutions and possible mechanisms involved are discussed.

Natural mineral waters: chemical characteristics and health effects

PubMed Central

Quattrini, Sara; Pampaloni, Barbara; Brandi, Maria Luisa

2016-01-01

Summary Water contributes significantly to health and a daily intake of 1.5 to 2 liters of water should be guaranteed, because a good hydration is essential to maintain the body water equilibrium, although needs may vary among people. However, worldwide population is far from the Recommended Allowance for water intake. Among the waters for human uses, there are ‘waters (treated or not), intended for drinking, used for the food and beverages preparation or for other domestic purposes’ and natural mineral waters, that are ‘originated from an aquifer or underground reservoir, spring from one or more natural or bore sources and have specific hygienic features and, eventually, healthy properties’. According to the European Legislation (2009/54/EC Directive), physical and chemical characterization is used to make a classification of the different mineral waters, basing on the analysis of main parameters. Mineral composition enables to classify natural mineral waters as bicarbonate mineral waters, sulphate mineral waters, chloride mineral waters, calcic mineral waters, magnesiac mineral waters, fluorurate mineral waters, ferrous mineral waters and sodium-rich mineral waters. Although the concerns about bottled mineral waters (due to plasticizers and endocrine disruptors), many are the health effects of natural mineral waters and several studies explored their properties and their role in different physiological and pathological conditions. PMID:28228777

Groundwater conditions in Utah, spring of 2011

USGS Publications Warehouse

Burden, Carole B.

2011-01-01

This is the forty-eighth in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions. This report, like the others in the series, contains information on well construction, groundwater withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of groundwater. Supplementary data are included in reports of this series only for those years or areas that are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2010. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http:// www.waterrights.utah.gov/techinfo/ and http://ut.water.usgs. gov/publications/GW2011.pdf. Groundwater conditions in Utah for calendar year 2009 are reported in Burden and others (2010) and available online at http://ut.water.usgs.gov/ publications/GW2010.pdf.Analytical results associated with water samples collected from each area of groundwater development were compared to State of Utah Maximum Contaminant Levels (MCLs) and secondary drinking-water standards of routinely measureable substances present in water supplies. The MCLs and secondary drinking-water standards can be accessed online at http://www.rules.utah.gov/publicat/code/r309/r309-200. htm#T5. The U.S. Environmental Protection Agency (EPA) drinking-water standards can be accessed at http://www.epa. gov/safewater/mcl.html#mcls. Maximum Contaminant Levels and secondary drinking-water standards were developed for public water systems and do not apply to the majority of wells sampled during this study.

Sustainability of water uses in managed hydrosystems: human- and climate-induced changes for the mid-21st century

DOE PAGES

Fabre, Julie; Ruelland, Denis; Dezetter, Alain; ...

2016-08-02

This paper assesses the sustainability of planned water uses in mesoscale river basins under multiple climate change scenarios, and contributes to determining the possible causes of unsustainability. We propose an assessment grounded in real-world water management issues, with water management scenarios built in collaboration with local water agencies. Furthermore, we present an analysis through indicators that relate to management goals and present the implications of climate uncertainty for our results, furthering the significance of our study for water management. A modeling framework integrating hydro-climatic and human dynamics and accounting for interactions between resource and demand was applied in two basinsmore » of different scales and with contrasting water uses: the Herault (2500 km 2, France) and the Ebro (85 000 km 2, Spain) basins. Natural streamflow was evaluated using a conceptual hydrological model. A demand-driven reservoir management model was designed to account for streamflow regulations from the main dams. Human water demand was estimated from time series of demographic, socioeconomic and climatic data. Environmental flows were accounted for by defining streamflow thresholds under which withdrawals were strictly limited. Finally indicators comparing water availability to demand at strategic resource and demand nodes were computed. This framework was applied under different combinations of climatic and water use scenarios for the mid-21st to differentiate the impacts of climate- and human-induced changes on streamflow and water balance. Results showed that objective monthly environmental flows would be guaranteed in current climate conditions in both basins, yet in several areas this could imply limiting human water uses more than once every 5 years. The impact of the tested climate projections on both water availability and demand could question the water allocations and environmental requirements currently planned for the coming decades. Water shortages for human use could become more frequent and intense, and the pressure on water resources and aquatic ecosystems could intensify. Furthermore, the causes of unsustainability vary across sub-basins and scenarios, and in most areas results are highly dependent on the climate change scenario.« less

Sustainability of water uses in managed hydrosystems: human- and climate-induced changes for the mid-21st century

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fabre, Julie; Ruelland, Denis; Dezetter, Alain

This paper assesses the sustainability of planned water uses in mesoscale river basins under multiple climate change scenarios, and contributes to determining the possible causes of unsustainability. We propose an assessment grounded in real-world water management issues, with water management scenarios built in collaboration with local water agencies. Furthermore, we present an analysis through indicators that relate to management goals and present the implications of climate uncertainty for our results, furthering the significance of our study for water management. A modeling framework integrating hydro-climatic and human dynamics and accounting for interactions between resource and demand was applied in two basinsmore » of different scales and with contrasting water uses: the Herault (2500 km 2, France) and the Ebro (85 000 km 2, Spain) basins. Natural streamflow was evaluated using a conceptual hydrological model. A demand-driven reservoir management model was designed to account for streamflow regulations from the main dams. Human water demand was estimated from time series of demographic, socioeconomic and climatic data. Environmental flows were accounted for by defining streamflow thresholds under which withdrawals were strictly limited. Finally indicators comparing water availability to demand at strategic resource and demand nodes were computed. This framework was applied under different combinations of climatic and water use scenarios for the mid-21st to differentiate the impacts of climate- and human-induced changes on streamflow and water balance. Results showed that objective monthly environmental flows would be guaranteed in current climate conditions in both basins, yet in several areas this could imply limiting human water uses more than once every 5 years. The impact of the tested climate projections on both water availability and demand could question the water allocations and environmental requirements currently planned for the coming decades. Water shortages for human use could become more frequent and intense, and the pressure on water resources and aquatic ecosystems could intensify. Furthermore, the causes of unsustainability vary across sub-basins and scenarios, and in most areas results are highly dependent on the climate change scenario.« less

Risks and responses to universal drinking water security.

PubMed

Hope, Robert; Rouse, Michael

2013-11-13

Risks to universal drinking water security are accelerating due to rapid demographic, climate and economic change. Policy responses are slow, uneven and largely inadequate to address the nature and scale of the global challenges. The challenges relate both to maintaining water security in increasingly fragile supply systems and to accelerating reliable access to the hundreds of millions who remain water-insecure. A conceptual framework illustrates the relationship between institutional, operational and financial risks and drinking water security outcomes. We apply the framework to nine case studies from rural and urban contexts in South Asia and sub-Saharan Africa. Case studies are purposively selected based on established and emerging examples of political, technological or institutional reforms that address water security risks. We find broad evidence that improved information flows reduce institutional costs and promote stronger and more transparent operational performance to increase financial sustainability. However, political barriers need to be overcome in all cases through internal or external interventions that require often decadal time frames and catalytic investments. No single model exists, though there is sufficient evidence to demonstrate that risks to drinking water security can be reduced even in the most difficult and challenging contexts.

Multi-criteria decision assessments using Subjective Logic: Methodology and the case of urban water strategies

NASA Astrophysics Data System (ADS)

Moglia, Magnus; Sharma, Ashok K.; Maheepala, Shiroma

2012-07-01

SummaryPlanning of regional and urban water resources, and in particular with Integrated Urban Water Management approaches, often considers inter-relationships between human uses of water, the health of the natural environment as well as the cost of various management strategies. Decision makers hence typically need to consider a combination of social, environmental and economic goals. The types of strategies employed can include water efficiency measures, water sensitive urban design, stormwater management, or catchment management. Therefore, decision makers need to choose between different scenarios and to evaluate them against a number of criteria. This type of problem has a discipline devoted to it, i.e. Multi-Criteria Decision Analysis, which has often been applied in water management contexts. This paper describes the application of Subjective Logic in a basic Bayesian Network to a Multi-Criteria Decision Analysis problem. By doing this, it outlines a novel methodology that explicitly incorporates uncertainty and information reliability. The application of the methodology to a known case study context allows for exploration. By making uncertainty and reliability of assessments explicit, it allows for assessing risks of various options, and this may help in alleviating cognitive biases and move towards a well formulated risk management policy.

Technological change in irrigated agriculture in a semiarid region of Spain

NASA Astrophysics Data System (ADS)

Philip, Jean-Marc; Sánchez-Chóliz, Julio; Sarasa, Cristina

2014-12-01

Technological change plays a decisive role in irrigated agriculture, which is particularly challenging in semiarid regions. The main objective of this paper is to assess four kinds of alternative technological improvements aimed at dealing with future water availability, especially in the case of extreme events like drought. We evaluate these technologies for a better understanding of what form should be applied in irrigated agriculture in a context of limits on natural resources. We develop a dynamic computable general equilibrium (CGE) model, whose production structure distinguishes between rainfed and irrigated crops, and between a variety of irrigated crops. Land use changes are also evaluated. As well as technological change, we consider the Water Framework Directive (EC 2000/60), which establishes water cost recovery as a key goal. Thus, we assess strategies that combine irrigation water pricing strategies and improved technology. Our results show that policy strategies that focus on fostering technical progress can mitigate the long-term economic effects of downward trends in water supplies, even in drought years. The study also confirms that the absence of price volatility achieved through a water pricing strategy could improve the sustainable use of water.

Concentration of organic compounds in natural waters with solid-phase dispersion based on advesicle modified silica prior to liquid chromatography.

PubMed

Parisis, Nikolaos A; Giokas, Dimosthenis L; Vlessidis, Athanasios G; Evmiridis, Nicholaos P

2005-12-02

The ability of vesicle-coated silica to aid the extraction of organic compounds from water prior to liquid chromatographic analysis is presented for the first time. The method is based on the formation of silica supported cationic multi-lamellar vesicles of gemini surfactants inherently ensuring the presence of hydrophilic and hydrophobic sites for the partitioning of analytes bearing different properties. Method development is illustrated by studying the adsolubilization of UV absorbing chemicals from swimming pool water. Due to the requirement for external energy input (intense shearing) a method based on solid-phase dispersion (SPD) was applied producing better results than off-line solid-phase extraction (SPE). Meticulous investigation of the experimental parameters was conducted in order to elucidate the mechanisms behind the proposed extraction pattern. Analyte recoveries were quantitative under the optimum experimental conditions offering recoveries higher than 96% with RSD values below 5%.

Relationship between landscape characteristics and surface water quality.

PubMed

Chang, C L; Kuan, W H; Lui, P S; Hu, C Y

2008-12-01

The effects of landscape characteristics on surface water quality were evaluated in terms of land-use condition, soil type and slope. The case area, the Chichiawan stream in the Wulin catchment in Taiwan, is Formosan landlocked salmon's natural habitat. Due to the agriculture behavior and mankind's activities, the water and environmental quality has gradually worsened. This study applied WinVAST model to predict hydrological responses and non-point source pollution (NPSP) exports in the Wulin catchment. The land-use condition and the slope of land surface in a catchment are major effect factors for watershed responses, including flows and pollutant exports. This work discussed the possible variation of watershed responses induced by the change of land-use condition, soil type and slope, etc. The results show that hydrological responses are highly relative to the value of Curve Number (CN); Pollutant exports have large relation to the average slope of the land surface in the Wulin catchment.

Lessons Learned from Comprehensive Energy and Water Evaluations at U.S. Army Campus Installations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodward, James C.; Dahowski, Robert T.

The U.S. Department of Energy’s Pacific Northwest National Laboratory has engaged in a multi-year collaboration with the U.S. Army to support comprehensive energy and water evaluations at large Army campus installations. Initiated to help the Army achieve compliance with facility evaluation requirements dictated by the Energy Independence and Security Act of 2007, this effort has resulted in the evaluation of 530 buildings at 14 installations across the U.S., and the identification of annual savings potential of over 212 billion Btu of energy and 29 million gallons of water. This paper highlights the nature of the evaluation process applied at thesemore » Army installations and discusses a number of key findings that can be considered for ongoing and future evaluations at Army and other federal agency facilities, particularly those buildings within campus settings.« less

Diversity of deep-water cetaceans in relation to temperature: implications for ocean warming.

PubMed

Whitehead, Hal; McGill, Brian; Worm, Boris

2008-11-01

Understanding the effects of natural environmental variation on biodiversity can help predict response to future anthropogenic change. Here we analyse a large, long-term data set of sightings of deep-water cetaceans from the Atlantic, Pacific and Indian Oceans. Seasonal and geographic changes in the diversity of these genera are well predicted by a convex function of sea-surface temperature peaking at c. 21 degrees C. Thus, diversity is highest at intermediate latitudes - an emerging general pattern for the pelagic ocean. When applied to a range of Intergovernmental Panel on Climate Change global change scenarios, the predicted response is a decline of cetacean diversity across the tropics and increases at higher latitudes. This suggests that deep-water oceanic communities that dominate > 60% of the planet's surface may reorganize in response to ocean warming, with low-latitude losses of diversity and resilience.

Seismic activity monitoring in the Izvorul Muntelui dam region

NASA Astrophysics Data System (ADS)

Borleanu, Felix; Otilia Placinta, Anca; Popa, Mihaela; Adelin Moldovan, Iren; Popescu, Emilia

2016-04-01

Earthquakes occurrences near the artificial water reservoirs are caused by stress variation due to the weight of water, weakness of fractures or faults and increasing of pore pressure in crustal rocks. In the present study we aim to investigate how Izvorul Muntelui dam, located in the Eastern Carpathians influences local seismicity. For this purpose we selected from the seismic bulletins computed within National Data Center of National Institute for Earth Physics, Romania, crustal events occurred between 984 and 2015 in a range of 0.3 deg around the artificial lake. Subsequently to improve the seismic monitoring of the region we applied a cross-correlation detector on the continuous recordings of Bicaz (BIZ) seismic stations. Besides the tectonic events we detected sources within this region that periodically generate artificial evens. We couldn't emphasize the existence of a direct correlation between the water level variations and natural seismicity of the investigated area.

Structure, chain conformation and antitumor activity of a novel polysaccharide from Lentinus edodes.

PubMed

Yu, Zhang; Ming, Gu; Kaiping, Wang; Zhixiang, Chen; Liquan, Dai; Jingyu, Liu; Fang, Zeng

2010-12-01

A water-soluble polysaccharide LT1 was isolated from the basidiocarps of Lentinus edodes by hot water extraction and ethanol precipitations, further purified by gel chromatography. The Mw of LT1 was estimated to be 642 kDa by using HPGPC. Chemical and spectroscopic studies illustrated that LT1 has a backbone chain composed of 1 → 4-linked and 1 → 3-linked glucopyranosyl residues and has branches of single glucosyl stubs at C-6 of β-(1 → 4)-linked glucopyranosyl. AFM and Congo-red test revealed that LT1 existed as triple helix chain in 0.10 M NaOH solution or distilled water. Our studies showed that LT1 presented significant antitumor bioactivities on Sarcoma180 solid tumor cell implanted in BALB/c mice, which implies that LT1 could be potentially applied as a natural antitumor drug. Copyright © 2010 Elsevier B.V. All rights reserved.

Modeling and Simulations in Photoelectrochemical Water Oxidation: From Single Level to Multiscale Modeling.

PubMed

Zhang, Xueqing; Bieberle-Hütter, Anja

2016-06-08

This review summarizes recent developments, challenges, and strategies in the field of modeling and simulations of photoelectrochemical (PEC) water oxidation. We focus on water splitting by metal-oxide semiconductors and discuss topics such as theoretical calculations of light absorption, band gap/band edge, charge transport, and electrochemical reactions at the electrode-electrolyte interface. In particular, we review the mechanisms of the oxygen evolution reaction, strategies to lower overpotential, and computational methods applied to PEC systems with particular focus on multiscale modeling. The current challenges in modeling PEC interfaces and their processes are summarized. At the end, we propose a new multiscale modeling approach to simulate the PEC interface under conditions most similar to those of experiments. This approach will contribute to identifying the limitations at PEC interfaces. Its generic nature allows its application to a number of electrochemical systems. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Discrimination of different sub-basins on Tajo River based on water influence factor

NASA Astrophysics Data System (ADS)

Bermudez, R.; Gascó, J. M.; Tarquis, A. M.; Saa-Requejo, A.

2009-04-01

Numeric taxonomy has been applied to classify Tajo basin water (Spain) till Portugal border. Several stations, a total of 52, that estimate 15 water variables have been used in this study. The different groups have been obtained applying a Euclidean distance among stations (distance classification) and a Euclidean distance between each station and the centroid estimated among them (centroid classification), varying the number of parameters and with or without variable typification. In order to compare the classification a log-log relation has been established, between number of groups created and distances, to select the best one. It has been observed that centroid classification is more appropriate following in a more logic way the natural constrictions than the minimum distance among stations. Variable typification doesn't improve the classification except when the centroid method is applied. Taking in consideration the ions and the sum of them as variables, the classification improved. Stations are grouped based on electric conductivity (CE), total anions (TA), total cations (TC) and ions ratio (Na/Ca and Mg/Ca). For a given classification and comparing the different groups created a certain variation in ions concentration and ions ratio are observed. However, the variation in each ion among groups is different depending on the case. For the last group, regardless the classification, the increase in all ions is general. Comparing the dendrograms, and groups that originated, Tajo river basin can be sub dived in five sub-basins differentiated by the main influence on water: 1. With a higher ombrogenic influence (rain fed). 2. With ombrogenic and pedogenic influence (rain and groundwater fed). 3. With pedogenic influence. 4. With lithogenic influence (geological bedrock). 5. With a higher ombrogenic and lithogenic influence added.

Pesticide transport with runoff from turf: observations compared with TurfPQ model simulations.

PubMed

Kramer, Kirsten E; Rice, Pamela J; Horgan, Brian P; Rittenhouse, Jennifer L; King, Kevin W

2009-01-01

Pesticides applied to turf grass have been detected in surface waters raising concerns of their effect on water quality and interest in their source, hydrological transport and use of models to predict transport. TurfPQ, a pesticide runoff model for turf grass, predicts pesticide transport but has not been rigorously validated for larger storms. The objective of this study was to determine TurfPQ's ability to accurately predict the transport of pesticides with runoff following more intense precipitation. The study was conducted with creeping bentgrass [Agrostis palustris Huds.] turf managed as a golf course fairway. A pesticide mixture containing dicamba, 2,4-D, MCPP, flutolanil, and chlorpyrifos was applied to six adjacent 24.4 by 6.1 m plots. Controlled rainfall simulations were conducted using a rainfall simulator designed to deliver water droplets similar to natural rain. Runoff flow rates and volume were measured and water samples were collected for analysis of pesticide concentrations. Six simulations yielded 13 events with which to test TurfPQ. Measured mean percentage of applied pesticide recovered in the runoff for dicamba, 2,4-D, MCPP, flutolanil, and chlorpyrifos was 24.6, 20.7, 14.9, 5.9, and 0.8%, respectively. The predicted mean values produced by TurfPQ were 13.7, 15.6, 15.5, 2.5, and 0.2%, respectively. The model produced correlations of r=0.56 and 0.64 for curve number hydrology and measured hydrology, respectively. Comparisons of the model estimates with our field observations indicate that TurfPQ under predicted pesticide runoff during 69.5+/-11.4 mm, 1.9+/-0.2 h, simulated storms.

Quantifying Impacts of Food Trade on Water Availability Considering Water Sources

NASA Astrophysics Data System (ADS)

Oki, T.; Yano, S.; Hanasaki, N.

2012-12-01

Food production requires a lot of water, and traded food potentially has external impacts on environment through reducing the water availability in the producing region. Water footprint is supposed to be an indicator to reflect the impacts of water use. However, impacts of water use on environment, resource, and sustainability are different in place and time, and according to the sources of water withdrawals. Therefore it is preferable to characterize the water withdrawals or consumptions rather than just accumulate the total amount of water use when estimating water footprint. In this study, a new methodology, global green-water equivalent method, is proposed in which regional characterization factors are determined based on the estimates of natural hydrological cycles, such as precipitation, total runoff, and sub-surface runoff, and applied for green-water, river(+reservoir) water, and non-renewable ground water uses. Water footprint of the world associated with the production of 19 major crops was estimated using an integrated hydrological and water resources modeling system (H08), with atmospheric forcing data for 1991-2000 with spatial resolution of 0.5 by 0.5 longitudinal and latitudinal degrees. The impacts is estimated to be 6 times larger than the simple summation of green and blue water uses, and reflect the climatological water scarcity conditions geographically. The results can be used to compare the possible impacts of food trade associated with various crops from various regions on environment through reducing the availability of water resources in the cropping area.

30 CFR 203.73 - How do suspension volumes apply to natural gas?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false How do suspension volumes apply to natural gas... suspension volumes apply to natural gas? You must measure natural gas production under the royalty-suspension volume as follows: 5.62 thousand cubic feet of natural gas, measured in accordance with 30 CFR part 250...

30 CFR 203.73 - How do suspension volumes apply to natural gas?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false How do suspension volumes apply to natural gas... § 203.73 How do suspension volumes apply to natural gas? You must measure natural gas production under the royalty-suspension volume as follows: 5.62 thousand cubic feet of natural gas, measured in...

An applied investigation of kenaf-based fiber/polymer composites as potential lightweight materials for automotive components

NASA Astrophysics Data System (ADS)

Du, Yicheng

Natural fibers have the potential to replace glass fibers in fiber-reinforced composite applications. However, the natural fibers' intrinsic properties cause these issues: (1) the mechanical property variation; (2) moisture uptake by natural fibers and their composites; (3) lack of sound, cost-effective, environment-friendly fiber-matrix compounding processes; (4) incompatibility between natural fibers and polymer matrices; and (5) low heat-resistance of natural fibers and their composites. This dissertation systematically studied the use of kenaf bast fiber bundles, obtained via a mechanical retting method, as a light-weight reinforcement material for fiber-reinforced thermoset polymer composites for automotive applications. Kenaf bast fiber bundle tensile properties were tested, and the effects of locations in the kenaf plant, loading rates, retting methods, and high temperature treatments and their durations on kenaf bast fiber bundle tensile properties were evaluated. A process has been developed for fabricating high fiber loading kenaf bast fiber bundle-reinforced unsaturated polyester composites. The generated composites possessed high elastic moduli and their tensile strengths were close to specification requirements for glass fiber-reinforced sheet molding compounds. Effects of fiber loadings and lengths on resultant composite's tensile properties were evaluated. Fiber loadings were very important for composite tensile modulus. Both fiber loadings and fiber lengths were important for composite tensile strengths. The distributions of composite tensile, flexural and impact strengths were analyzed. The 2-parameter Weibull model was found to be the most appropriate for describing the composite strength distributions and provided the most conservative design values. Kenaf-reinforced unsaturated polyester composites were also proved to be more cost-effective than glass fiber-reinforced SMCs at high fiber loadings. Kenaf bast fiber bundle-reinforced composite's water absorption properties were tested. Surface-coating and edge-sealing significantly reduced composite water resistance properties. Encapsulation was a practical method to improve composite water resistance properties. The molding pressure and styrene concentrations on composite and matrix properties were evaluated. Laser and plasma treatment improved fiber-to-matrix adhesion.

Geology, ground-water hydrology, geochemistry, and ground-water simulation of the Beaumont and Banning Storage Units, San Gorgonio Pass area, Riverside County, California

USGS Publications Warehouse

Rewis, Diane L.; Christensen, Allen H.; Matti, Jonathan; Hevesi, Joseph A.; Nishikawa, Tracy; Martin, Peter

2006-01-01

Ground water has been the only source of potable water supply for residential, industrial, and agricultural users in the Beaumont and Banning storage units of the San Gorgonio Pass area, Riverside County, California. Ground-water levels in the Beaumont area have declined as much as 100 feet between the early 1920s and early 2000s, and numerous natural springs have stopped flowing. In 1961, the San Gorgonio Pass Water Agency (SGPWA) entered into a contract with the California State Department of Water Resources to receive 17,300 acre-feet per year of water to be delivered by the California State Water Project (SWP) to supplement natural recharge. Currently (2005), a pipeline is delivering SWP water into the area, and the SGPWA is artificially recharging the ground-water system using recharge ponds located along Little San Gorgonio Creek in Cherry Valley with the SWP water. In addition to artificial recharge, SGPWA is considering the direct delivery of SWP water for the irrigation of local golf courses and for agricultural supply in lieu of ground-water pumpage. To better understand the potential hydrologic effects of different water-management alternatives on ground-water levels and movement in the Beaumont and Banning storage units, existing geohydrologic and geochemical data were compiled, new data from a basin-wide ground-water level and water-quality monitoring network were collected, monitoring wells were installed near the Little San Gorgonio Creek recharge ponds, geohydrologic and geochemical analyses were completed, and a ground-water flow simulation model was developed. The San Gorgonio Pass area was divided into several storage units on the basis of mapped or inferred faults. This study addresses primarily the Beaumont and Banning storage units. The geologic units in the study area were generalized into crystalline basement rocks and sedimentary deposits. The younger sedimentary deposits and the surficial deposits are the main water-bearing deposits in the San Gorgonio Pass area. The water-bearing deposits were divided into three aquifers: (1) the perched aquifer, (2) the upper aquifer, and (3) the lower aquifer based on lithologic and downhole geophysical logs. Natural recharge in the San Gorgonio Pass area was estimated using INFILv3, a deterministic distributed- parameter precipitation-runoff model. The INFILv3 model simulated that the potential recharge of precipitation and runoff in the Beaumont and Banning storage units was about 3,710 acre-feet per year and that the potential recharge in 28 sub-drainage basins upstream of the storage units was about 6,180 acre-feet per year. The water supply for the Beaumont and Banning storage units is supplied by pumping ground water from wells in the Canyon (Edgar and Banning Canyons), Banning Bench, Beaumont, and Banning storage units. Total annual pumpage from the Beaumont and Banning storage units ranged from about 1,630 acre-feet in 1936 to about 20,000 acre-feet in 2003. Ground-water levels declined by as much as 100 feet in the Beaumont storage unit from 1926-2003 in response to ground-water pumping of about 450,160 acre-feet during this period. Since ground-water development began in the San Gorgonio Pass area, there have been several sources of artificial recharge to the basin including return flow from applied water on crops, golf courses, and landscape; septic-tank seepage; and infiltration of storm runoff diversions and imported water into recharge ponds. Return flow from applied water and septic-tank seepage was estimated to reach a maximum of about 8,100 acre-feet per year in 2003. Owing to the great depth of water in much of study area (in excess of 150 feet), the return flow and septic-tank seepage takes years to decades to reach the water table. Stable-isotope data indicate that the source of ground-water recharge was precipitation from storms passing through the San Gorgonio Pass as opposed to runoff from the higher altitudes of the San Bernar

A green and facile preparation approach, licochalcone A capped on hollow gold nanoparticles, for improving the solubility and dissolution of anticancer natural product.

PubMed

Sun, Yi-Wei; Wang, Li-Hong; Meng, Da-Li; Che, Xin

2017-12-01

This study described a valuable drug delivery system for poorly water-soluble anticancer naturalproduct, licochalcone A, isolated from Glycyrrhiza inflata , loaded on hollow gold nanoparticles by green method to improve solubility and dissolution and maintain its natural pharmacological property. Briefly, the formation of hollow gold nanoparticles involves three steps: preparing of silica nanospheres by Stober method, forming of a thick gold shell around the silica templates and etching of silica particles by HF solution. Hollow gold nanoparticles (HGNPs) and drug loaded hollow gold nanoparticles (L-HGNPs) displayed spherical structure and approximately 200nm in size observed by SEM, XRD, EDS and DSC analysis showed that HGNPs were gold hollow structure and crystalline form. The solubility in aqueous solution of licochalcone A was increased obviously to 488.9 μg/ml, compared with free drugs of 136.1 μg/ml. Another interesting finding is that near-infrared (NIR) irradiation increased the speed of solubility of licochalcone A in aqueous solutions, rather than quantity. In short, the method of nano-delivery system combined with poorly water-soluble drug to improve its solubility and dissolution is worth applying to other natural products in order to increase their opportunities in clinical applications.

Integrating developed and developing world knowledge into global discussions and strategies for sustainability. 1. Science and technology.

PubMed

Mihelcic, James R; Zimmerman, Julie B; Ramaswami, Anu

2007-05-15

Sustainable development in both the developed and developing world has the common fundamental themes of advancing economic and social prosperity while protecting and restoring natural systems. While many recent efforts have been undertaken to transfer knowledge from the developed to the developing world to achieve a more sustainable future, indigenous knowledge that often originates in developing nations also can contribute significantly to this global dialogue. Selected case studies are presented to describe important knowledge, methodologies, techniques, principles, and practices for sustainable development emerging from developing countries in two critical challenge areas to sustainability: water and energy. These, with additional analysis and quantification, can be adapted and expanded for transfer throughout the developed and developing world in advancing sustainability. A common theme in all of the case studies presented is the integration of natural processes and material flows into the anthropogenic system. Some of these techniques, originating in rural settings, have recently been adapted for use in cities, which is especially important as the global trend of urban population growth accelerates. Innovations in science and technology, specifically applied to two critical issues of today, water and energy, are expected to fundamentally shift the type and efficiency of energy and materials utilized to advance prosperity while protecting and restoring natural systems.

Microbial Oxidation of Natural Gas in a Plume Emanating from the Coal Oil Point Seep Field

NASA Astrophysics Data System (ADS)

Mendes, S. D.; Valentine, D. L.; Perez, C.; Scarlett, R.

2012-12-01

The hydrocarbon seep field at Coal Oil Point, off the coast of Santa Barbara, California, releases > 1010 g of thermogenic natural gas each year. Gases emitted from Coal Oil Point include methane, ethane, propane, and butane, which are atmospheric pollutants and greenhouse gases. Even though the seeps are at water depths of only 5-80 m, much of the gas dissolves and contributes to a plume that is transported by ocean currents. While hydrocarbons can support bacterial respiration, resulting in the removal of hydrocarbon gas from the plume, the time-scale for the bacterial respiratory response is unconstrained. To track hydrocarbon respiration 3H-ethane, propane, and butane were synthesized using Grignard reagents and tritiated water with yields of >70% and applied as tracers to samples up- and down-current from the seeps at Coal Oil Point. Validation experiments conducted in September 2011 aboard the R/V Atlantis show that 3H-labeled tracers are an order of magnitude more sensitive than previous methods using stable carbon isotopes (Valentine et. al 2010), making this technique preferable in natural systems. Application of the tracers concurrent with plume tracking in July-August 2012 show ethane, propane, and butane consumption are readily inducible on a timescale of days.

Quantifying Anthropogenic Stress on Groundwater Resources.

PubMed

Ashraf, Batool; AghaKouchak, Amir; Alizadeh, Amin; Mousavi Baygi, Mohammad; R Moftakhari, Hamed; Mirchi, Ali; Anjileli, Hassan; Madani, Kaveh

2017-10-10

This study explores a general framework for quantifying anthropogenic influences on groundwater budget based on normalized human outflow (h out ) and inflow (h in ). The framework is useful for sustainability assessment of groundwater systems and allows investigating the effects of different human water abstraction scenarios on the overall aquifer regime (e.g., depleted, natural flow-dominated, and human flow-dominated). We apply this approach to selected regions in the USA, Germany and Iran to evaluate the current aquifer regime. We subsequently present two scenarios of changes in human water withdrawals and return flow to the system (individually and combined). Results show that approximately one-third of the selected aquifers in the USA, and half of the selected aquifers in Iran are dominated by human activities, while the selected aquifers in Germany are natural flow-dominated. The scenario analysis results also show that reduced human withdrawals could help with regime change in some aquifers. For instance, in two of the selected USA aquifers, a decrease in anthropogenic influences by ~20% may change the condition of depleted regime to natural flow-dominated regime. We specifically highlight a trending threat to the sustainability of groundwater in northwest Iran and California, and the need for more careful assessment and monitoring practices as well as strict regulations to mitigate the negative impacts of groundwater overexploitation.

Historical trends in organochlorine compounds in river basins identified using sediment cores from reservoirs

USGS Publications Warehouse

Van Metre, P.C.; Callender, E.; Fuller, C.C.

1997-01-01

This study used chemical analyses of dated sediment cores from reservoirs to define historical trends in water quality in the influent river basins. This work applies techniques from paleolimnology to reservoirs, and in the process, highlights differences between sediment-core interpretations for reservoirs and natural lakes. Sediment cores were collected from six reservoirs in the central and southeastern United States, sectioned, and analyzed for 137Cs and organochlorine compounds. 137Cs analyses were used to demonstrate limited post-depositional mixing, to indicate sediment deposition dates, and to estimate sediment focusing factors. Relative lack of mixing, high sedimentation rates, and high focusing factors distinguish reservoir sediment cores from cores collected in natural lakes. Temporal trends in concentrations of PCBs, total DDT (DDT + DDD + DDE), and chlordane reflect historical use and regulation of these compounds and differences in land use between reservoir drainages. PCB and total DDT core burdens, normalized for sediment focusing, greatly exceed reported cumulative regional atmospheric fallout of PCBs and total DDT estimated using cores from peat hogs and natural lakes, indicating the dominance of fluvial inputs of both groups of compounds to the reservoirs.This study used chemical analyses of dated sediment cores from reservoirs to define historical trends in water quality in the influent river basins. This work applies techniques from paleolimnology to reservoirs, and in the process, highlights differences between sediment-core interpretations for reservoirs and natural lakes. Sediment cores were collected from six reservoirs in the central and southeastern United States, sectioned, and analyzed for 137Cs and organochlorine compounds. 137Cs analyses were used to demonstrate limited post-depositional mixing, to indicate sediment deposition dates, and to estimate sediment focusing factors. Relative lack of mixing, high sedimentation rates, and high focusing factors distinguish reservoir sediment cores from cores collected in natural lakes. Temporal trends in concentrations of PCBs, total DOT (DDT+DDD+DDE), and chlordane reflect historical use and regulation of these compounds and differences in land use between reservoir drainages. PCB and total DDT core burdens, normalized for sediment focusing, greatly exceed reported cumulative regional atmospheric fallout of PCBs and total DDT estimated using cores from peat bogs and natural lakes, indicating the dominance of fluvial inputs of both groups of compounds to the reservoirs.

Mechanisms and kinetics study on the trihalomethanes formation with carbon nanoparticle precursors.

PubMed

Du, Tingting; Wang, Yingying; Yang, Xin; Wang, Wei; Guo, Haonan; Xiong, Xinyu; Gao, Rui; Wuli, Xiati; Adeleye, Adeyemi S; Li, Yao

2016-07-01

With lots of carbon nanoparticles (CNPs) applied in the industry, the possibilities of their environmental release have received much attention. As the CNPs may enter drinking water systems, and persist in water and wastewater treatment systems, their possible reaction with disinfectants should be studied. In this study, the formation of trihalomethanes (THMs) with 5 types of carbon nanotubes (CNTs), graphene oxide (GO) and reduced graphene oxide (rGO) was investigated. All CNPs could act as precursors of THMs in aqueous phase. Total concentrations of THMs formed with CNPs varied from 0.24 to 0.95 μM, much lower than that formed from chlorinated Suwannee River Natural Organic Matter (SRNOM) (approximately 9 μM). The kinetics of THMs formation with GO was 0.0814 M(-1) s(-1), which is higher than most of the chlorinated humic acid obtained from different natural waters. The study indicates that during chlorination, C-Cl bond could be formed on the surface of CNPs. However, carbon atoms at the middle of two meta-positioned OH groups on the benzene ring are more active and may prefer to form THMs with chlorine oxidation. The influences of pH and reactant doses on the formation of THMs were also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Critical level of water recharges in the catchment areas of Manna watershed Bengkulu Province Indonesia

NASA Astrophysics Data System (ADS)

Amri, Khairul; Nugraha, Loparedo; Barchia, Muhammad Faiz

2017-11-01

Land use changes in Manna watershed are caused degradation in the watershed functions. When water infiltration goes down, some water runs off flowing to Manna River cause submerged on the downstream. The aim of this study is to analyze how the Manna watershed overcoming environmentally degraded conditions. The critical level of the Manna catchment areas was determined by overlaying some digital maps based on procedure applying in the Ministry of Forestry, Republic of Indonesia (P.32/MENHUT-II/2009). Measuring the critical level of the catchment also needed natural and actual infiltrations map, and the interpretation process of the analysis used ArcGIS 10.1 software. Based on the spatial data analysis by overlaying maps of slope, soils, and rainfall, the natural infiltration rate in the Manna watershed categorized high level (44.1%). While, the critical level of the catchment areas of the Manna watershed classified in good condition cover about 64,5 % of the areas, and starting to degraded state cover about 35,5 % of the watershed areas. The environment degradation conditions indicated the land use changes in the Manna watershed could deteriorate infiltration rates. The cultivated agricultural activities neglected conservation rule could accelerate the critical catchment areas in the Manna watershed.

Building agribusiness model of LEISA to achieve sustainable agriculture in Surian Subdistrict of Sumedang Regency West Java Indonesia

NASA Astrophysics Data System (ADS)

Djuwendah, E.; Priyatna, T.; Kusno, K.; Deliana, Y.; Wulandari, E.

2018-03-01

Building agribusiness model of LEISA is needed as a prototype of sustainable regional and economic development (SRRED) in the watersheds (DAS) of West Java Province. Agribusiness model of LEISA is a sustainable agribusiness system applying low external input. The system was developed in the framework of optimizing local-based productive resources including soil, water, vegetation, microclimate, renewable energy, appropriate technology, social capital, environment and human resources by combining various subsystems including integrated production subsystems of crops, livestock and fish to provide a maximum synergy effect, post-harvest subsystem and processing of results, marketing subsystems and supporting subsystems. In this study, the ecological boundary of Cipunegara sub-watershed ecosystem, administrative boundaries are Surian Subdistricts in Sumedang. The purpose of this study are to identify the potency of natural resources and local agricultural technologies that could support the LEISA model in Surian and to identify the potency of internal and external inputs in the LEISA model. The research used qualitative descriptive method and technical action research. Data were obtained through interviews, documentation, and observation. The results showed that natural resources in the form of agricultural land, water resources, livestock resources, and human labor are sufficient to support agribusiness model of LEISA. LEISA agribusiness model that has been applied in the research location is the integration of beef cattle, agroforestry, and agrosilvopasture. By building LEISA model, agribusiness can optimize the utilization of locally based productive resources, reduce dependence on external resources, and support sustainable food security.

Quantification of groundwater recharge in urban environments.

PubMed

Tubau, Isabel; Vázquez-Suñé, Enric; Carrera, Jesús; Valhondo, Cristina; Criollo, Rotman

2017-08-15

Groundwater management in urban areas requires a detailed knowledge of the hydrogeological system as well as the adequate tools for predicting the amount of groundwater and water quality evolution. In that context, a key difference between urban and natural areas lies in recharge evaluation. A large number of studies have been published since the 1990s that evaluate recharge in urban areas, with no specific methodology. Most of these methods show that there are generally higher rates of recharge in urban settings than in natural settings. Methods such as mixing ratios or groundwater modeling can be used to better estimate the relative importance of different sources of recharge and may prove to be a good tool for total recharge evaluation. However, accurate evaluation of this input is difficult. The objective is to present a methodology to help overcome those difficulties, and which will allow us to quantify the variability in space and time of the recharge into aquifers in urban areas. Recharge calculations have been initially performed by defining and applying some analytical equations, and validation has been assessed based on groundwater flow and solute transport modeling. This methodology is applicable to complex systems by considering temporal variability of all water sources. This allows managers of urban groundwater to evaluate the relative contribution of different recharge sources at a city scale by considering quantity and quality factors. The methodology is applied to the assessment of recharge sources in the Barcelona city aquifers. Copyright © 2017 Elsevier B.V. All rights reserved.

Biodegradation of artificial monolayers applied to water storages to reduce evaporative loss.

PubMed

Pittaway, P; Herzig, M; Stuckey, N; Larsen, K

2015-01-01

Repeat applications of an artificial monolayer to the interfacial boundary layer of large agricultural water storages during periods of high evaporative demand remains the most commercially feasible water conservation strategy. However, the interfacial boundary layer (or microlayer) is ecologically distinct from subsurface water, and repeat monolayer applications may adversely affect microlayer processes. In this study, the natural cleansing mechanisms operating within the microlayer were investigated to compare the biodegradability of two fatty alcohol (C16OH and C18OH) and one glycol ether (C18E1) monolayer compound. The C16OH and C18OH compounds were more susceptible to microbial degradation, but the C18E1 compound was most susceptible to indirect photodegradation. On clean water the surface pressure and evaporation reduction achieved with a compressed C18E1 monolayer was superior to the C18OH monolayer, but on brown water the surface pressure dropped rapidly. These results suggest artificial monolayers are readily degraded by the synergy between photo and microbial degradation. The residence time of C18OH and C18E1 monolayers on clear water is sufficient for cost-effective water conservation. However, the susceptibility of C18E1 to photodegradation indicates the application of this monolayer to brown water may not be cost-effective.

Influence of acid rain upon water plumbosolvency.

PubMed Central

Moore, M R

1985-01-01

The West of Scotland has had particular problems in the past associated with soft acidic water supplies and uptake of lead from domestic plumbing systems by such water. As a consequence of this, health problems related to overexposure to lead have been identified. The current debate on acidification of ground waters by acid rain is therefore particularly pertinent to this area. Studies have shown that even a modest decrease in pH will result in very substantial increase in plumbosolvency. This was found to be of particular importance in the city of Glasgow and town of Ayr, where prior to water treatment, pH values were 6.3 and 5.4, respectively, and where, consequentially, large numbers of homes did not comply with lead in water standards. Closed-loop lime-dosing systems were introduced in both Glasgow and Ayr to increase the pH with immediate decrease in the lead content of the water and, subsequently, blood lead concentrations of the subjects living in these areas. Such closed-loop systems will compensate for any acidity in water supplies, whether of natural origin or originating from acid rain precipitation. However, when such treatment has not been applied, any increase in water acidity due to acid rain which is, in many cases, already unacceptable. which is, in many cases, already unacceptable. PMID:4076078

Comparison of electrical conductivity calculation methods for natural waters

USGS Publications Warehouse

McCleskey, R. Blaine; Nordstrom, D. Kirk; Ryan, Joseph N.

2012-01-01

The capability of eleven methods to calculate the electrical conductivity of a wide range of natural waters from their chemical composition was investigated. A brief summary of each method is presented including equations to calculate the conductivities of individual ions, the ions incorporated, and the method's limitations. The ability of each method to reliably predict the conductivity depends on the ions included, effective accounting of ion pairing, and the accuracy of the equation used to estimate the ionic conductivities. The performances of the methods were evaluated by calculating the conductivity of 33 environmentally important electrolyte solutions, 41 U.S. Geological Survey standard reference water samples, and 1593 natural water samples. The natural waters tested include acid mine waters, geothermal waters, seawater, dilute mountain waters, and river water impacted by municipal waste water. The three most recent conductivity methods predict the conductivity of natural waters better than other methods. Two of the recent methods can be used to reliably calculate the conductivity for samples with pH values greater than about 3 and temperatures between 0 and 40°C. One method is applicable to a variety of natural water types with a range of pH from 1 to 10, temperature from 0 to 95°C, and ionic strength up to 1 m.

A risk-based framework to assess long-term effects of policy and water supply changes on water resources systems

NASA Astrophysics Data System (ADS)

Hassanzadeh, Elmira; Elshorbagy, Amin; Wheater, Howard; Gober, Patricia

2015-04-01

Climate uncertainty can affect water resources availability and management decisions. Sustainable water resources management therefore requires evaluation of policy and management decisions under a wide range of possible future water supply conditions. This study proposes a risk-based framework to integrate water supply uncertainty into a forward-looking decision making context. To apply this framework, a stochastic reconstruction scheme is used to generate a large ensemble of flow series. For the Rocky Mountain basins considered here, two key characteristics of the annual hydrograph are its annual flow volume and the timing of the seasonal flood peak. These are perturbed to represent natural randomness and potential changes due to future climate. 30-year series of perturbed flows are used as input to the SWAMP model - an integrated water resources model that simulates regional water supply-demand system and estimates economic productivity of water and other sustainability indicators, including system vulnerability and resilience. The simulation results are used to construct 2D-maps of net revenue of a particular water sector; e.g., hydropower, or for all sectors combined. Each map cell represents a risk scenario of net revenue based on a particular annual flow volume, timing of the peak flow, and 200 stochastic realizations of flow series. This framework is demonstrated for a water resources system in the Saskatchewan River Basin (SaskRB) in Saskatchewan, Canada. Critical historical drought sequences, derived from tree-ring reconstructions of several hundred years of annual river flows, are used to evaluate the system's performance (net revenue risk) under extremely low flow conditions and also to locate them on the previously produced 2D risk maps. This simulation and analysis framework is repeated under various reservoir operation strategies (e.g., maximizing flood protection or maximizing water supply security); development proposals, such as irrigation expansion; and change in energy prices. Such risk-based analysis demonstrates relative reduction/increase of risk associated with management and policy decisions and allow decision makers to explore the relative importance of policy versus natural water supply change in a water resources system.

A Spike Cocktail Approach to Improve Microbial Performance ...

EPA Pesticide Factsheets

Water reuse, via either centralized treatment of traditional wastewater or decentralized treatment and on-site reuse, is becoming an increasingly important element of sustainable water management. Despite advances in waterborne pathogen detection methods, low and highly variable pathogen levels limit their utility for routine evaluation of health risks in water reuse systems. Therefore, there is a need to improve our understanding of the linkage between pathogens and more readily measured process indicators during treatment. This paper describes an approach for constructing spiking experiments to relate the behavior of viral, bacterial, and protozoan pathogens with relevant process indicators. General issues are reviewed, and the spiking protocol is applied as a case study example to improve microbial performance monitoring and health risk evaluation in a water reuse system. This approach provides a foundation for the development of novel approaches to improve real or near-real time performance monitoring of water recycling systems. This manuscrupt details an approach for developing "spike cocktail", a mixture of microorganisms that can be used to evaluate the performance of engineered and natural systems.

Flood induced infiltration affecting a bank filtrate well at the River Enns, Austria

NASA Astrophysics Data System (ADS)

Wett, Bernhard; Jarosch, Hannes; Ingerle, Kurt

2002-09-01

Bank filtration employs a natural filtration process of surface water on its flow path from the river to the well. The development of a stable filter layer is of major importance to the quality of the delivered water. Flooding is expected to destabilise the riverbed, to reduce the filter efficiency of the bank and therefore to endanger the operation of water supply facilities near the riverbank. This paper provides an example of how bank storage in an unconfined alluvial aquifer causes a significant decrease of the seepage rate after a high-water event. Extensive monitoring equipment has been installed in the river bank of the oligotrophic alpine River Enns focusing on the first metre of the flow path. Head losses measured by multilevel probes throughout a year characterise the development of the hydraulic conductivity of different riverbed layers. Concentration profiles of nitrate, total ions and a NaCl tracer have been used to study infiltration rates of river water and its dilution with groundwater. Dynamic modelling was applied in order to investigate the propagation of flood induced head elevation and transport of pollutants.

A unified model of bedforms in water, Earth and other planetary bodies

NASA Astrophysics Data System (ADS)

Duran Vinent, O.; Claudin, P.; Winter, C.; Andreotti, B.

2017-12-01

The emergence of bedforms as result of the coupling between a fluid flow and sediment transport is a remarkable example of self-organized natural patterns. Subaqueous bedforms generated by unidirectional water flows, like ripples, dunes or compound bedforms, have been shown to depend on grain size, water depth and flow velocity. However, this variety of morphologies, empirically classified according to their size, is still not understood in terms of mechanical and hydrodynamical mechanisms. We present a process-based model that simultaneously explain the scaling of bedforms for Water, Air, Mars and Venus, and can be potentially applied to other planetary bodies such as Titan or Pluto. The model couples hydrodynamics over a modulated bed to sediment transport and relaxation laws, and resolves pattern coarsening from initial to mature bedforms. We find two fundamental types of bedforms, called `laminar' and `turbulent' and analogous to water ripples and dunes, and the conditions leading to their formation. By relating morphology to hydrodynamic and sediment transport details, our model opens the way to extract hydrodynamic information from the stratigraphy record and shed a light to past and current planetary conditions.

Increased Power in Sediment Microbial Fuel Cell: Facilitated Mass Transfer via a Water-Layer Anode Embedded in Sediment.

PubMed

Lee, Yoo Seok; An, Junyeong; Kim, Bongkyu; Park, HyunJun; Kim, Jisu; Chang, In Seop

2015-01-01

We report a methodology for enhancing the mass transfer at the anode electrode of sediment microbial fuel cells (SMFCs), by employing a fabric baffle to create a separate water-layer for installing the anode electrode in sediment. The maximum power in an SMFC with the anode installed in the separate water-layer (SMFC-wFB) was improved by factor of 6.6 compared to an SMFC having the anode embedded in the sediment (SMFC-woFB). The maximum current density in the SMFC-wFB was also 3.9 times higher (220.46 mA/m2) than for the SMFC-woFB. We found that the increased performance in the SMFC-wFB was due to the improved mass transfer rate of organic matter obtained by employing the water-layer during anode installation in the sediment layer. Acetate injection tests revealed that the SMFC-wFB could be applied to natural water bodies in which there is frequent organic contamination, based on the acetate flux from the cathode to the anode.

75 FR 11194 - San Diego County Water Authority Natural Communities Conservation Program/Habitat Conservation...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-10

... Diego County Water Authority Natural Communities Conservation Program/Habitat Conservation Plan, San... meetings for the San Diego County Water Authority's (Water Authority/Applicant) draft Natural Communities Conservation Plan (NCCP)/Habitat Conservation Plan (HCP) prepared in application to us for an incidental take...

Selective flotation-spectrophotometric determination of trace copper(II) in natural waters, human blood and drug samples using phenanthraquinone monophenylthiosemicarbazone.

PubMed

Khalifa, M E; Akl, M A; Ghazy, S E

2001-06-01

Copper(II) forms 1:1 and 1:2 intense red complexes with phenanthraquinone monophenylthiosemicarbazone (PPT) at pH 3-3.5 and > or =6.5, respectively. These complexes exhibit maximal absorbance at 545 and 517 nm, the molar absorptivity being 2.3 x 10(4) and 4.8 x 10(4) l mol(-1) cm(-1), respectively. However, the 1:1 complex was quantitatively floated with oleic acid (HOL) surfactant in the pH range 4.5-5.5, providing a highly selective and sensitive procedure for the spectrophotometric determination of CuII. The molar absorptivity of the floated Cu-PPT complex was 1.5 x 10(5) l mol)(-1) cm(-1). Beer's law was obeyed over the range 3-400 ppb at 545 nm. The analytical parameters affecting the flotation process and hence the determination of copper traces were reported. Also, the structure of the isolated solid complex and the mechanism of flotation were suggested. Moreover, the procedure was successfully applied to the analysis of CuII in natural waters, serum blood and some drug samples.

Recovery of oil from oil-in-water emulsion using biopolymers by adsorptive method.

PubMed

Elanchezhiyan, S Sd; Sivasurian, N; Meenakshi, Sankaran

2014-09-01

In the present study, it is aimed to identify, a low cost sorbent for the recovery of oil from oil-in-water emulsion using biopolymers such as chitin and chitosan. Chitin has the greater adsorption capacity than chitosan due to its hydrophobic nature. The characterizations of chitin and chitosan were done using FTIR, SEM, EDAX, XRD, TGA and DSC techniques. Under batch equilibrium mode, a systematic study was performed to optimize the various equilibrium parameters viz., contact time, pH, dosage, initial concentration of oil, and temperature. The adsorption process reached equilibrium at 40 min of contact time and the percentage removal of oil was found to be higher (90%) in the acidic medium. The Freundlich and Langmuir models were applied to describe the equilibrium isotherms and the isotherm constants were calculated. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated to find out the nature of the sorption mechanism. The kinetic studies were investigated with reaction-based and diffusion-based models. The suitable mechanism for the removal of oil has been established. Copyright © 2014 Elsevier B.V. All rights reserved.

A Techno-Economic Assessment of Hybrid Cooling Systems for Coal- and Natural-Gas-Fired Power Plants with and without Carbon Capture and Storage.

PubMed

Zhai, Haibo; Rubin, Edward S

2016-04-05

Advanced cooling systems can be deployed to enhance the resilience of thermoelectric power generation systems. This study developed and applied a new power plant modeling option for a hybrid cooling system at coal- or natural-gas-fired power plants with and without amine-based carbon capture and storage (CCS) systems. The results of the plant-level analyses show that the performance and cost of hybrid cooling systems are affected by a range of environmental, technical, and economic parameters. In general, when hot periods last the entire summer, the wet unit of a hybrid cooling system needs to share about 30% of the total plant cooling load in order to minimize the overall system cost. CCS deployment can lead to a significant increase in the water use of hybrid cooling systems, depending on the level of CO2 capture. Compared to wet cooling systems, widespread applications of hybrid cooling systems can substantially reduce water use in the electric power sector with only a moderate increase in the plant-level cost of electricity generation.

Review--Interactions between diatoms and stainless steel: focus on biofouling and biocorrosion.

PubMed

Landoulsi, J; Cooksey, K E; Dupres, V

2011-11-01

There is a considerable body of information regarding bacterially enhanced corrosion, however, this review focuses on diatoms (unicellular algae) whose contribution to biocorrosion is less well studied. The reasons why diatoms have been neglected in studies of biocorrosion in natural waters are discussed and the question whether diatoms should be considered as inert with respect of electrochemical processes is considered. A particular focus is given to the case of stainless steels (SS), which are widely used in variety of applications in natural waters. Basic information on the cell biology of diatoms is included in the review, particularly with respect to their ability to 'sense' and adhere to surfaces. Investigations at the nanoscale are reviewed as these studies provide information about the behavior of cells at interfaces. Recent advances include the use of atomic force microscopy (AFM), although only a few studies have been applied to diatoms. Regarding the electrochemical behavior of SS, the mechanisms by which diatoms influence the potential ennoblement process is discussed. Such studies reveal the association of diatoms, in addition to bacteria, with biocorrosion processes.

Turbulence increases the average settling velocity of phytoplankton cells

PubMed Central

Ruiz, Javier; Macías, Diego; Peters, Francesc

2004-01-01

It is a well known fact that stirring keeps particles suspended in fluids. This is apparent, for instance, when shaking medicine flasks, when agitating tea deposits in a mug, or when heavy winds fill the air with dust particles. The commonplace nature of such observations makes it easy to accept that this feature will apply to any natural phenomenon as long as the flow is turbulent enough. This has been the case for phytoplankton in the surface mixed layers of lakes and oceans. The traditional view assumes that an increase in turbulence bears ecological advantages for nonmotile groups like diatoms that, otherwise, would settle in deep and unlit waters. However, this assumption has no theoretical ground, and the experimental results we present here point in the opposite direction. Phytoplankton settling velocity increases when turbulence intensifies from the low to the higher values recorded in the upper mixed layers of lakes and oceans. Consequently, turbulence does not favor phytoplankton remaining in lit waters but is rather an environmental stress that can only be avoided through morphological and/or physiological adaptations. PMID:15601780

Modeling the resilience of urban water supply using the capital portfolio approach

NASA Astrophysics Data System (ADS)

Krueger, E. H.; Klammler, H.; Borchardt, D.; Frank, K.; Jawitz, J. W.; Rao, P. S.

2017-12-01

The dynamics of global change challenge the resilience of cities in a multitude of ways, including pressures resulting from population and consumption changes, production patterns, climate and landuse change, as well as environmental hazards. Responses to these challenges aim to improve urban resilience, but lack an adequate understanding of 1) the elements and processes that lead to the resilience of coupled natural-human-engineered systems, 2) the complex dynamics emerging from the interaction of these elements, including the availability of natural resources, infrastructure, and social capital, which may lead to 3) unintended consequences resulting from management responses. We propose a new model that simulates the coupled dynamics of five types of capitals (water resources, infrastructure, finances, political capital /management, and social adaptive capacity) that are necessary for the provision of water supply to urban residents. We parameterize the model based on data for a case study city, which is limited by constraints in water availability, financial resources, and faced with degrading infrastructure, as well as population increase, which challenge the urban management institutions. Our model analyzes the stability of the coupled system, and produces time series of the capital dynamics to quantify its resilience as a result of the portfolio of capitals available to usher adaptive capacity and to secure water supply subjected to multiple recurring shocks. We apply our model to one real urban water supply system located in an arid environment, as well as a wide range of hypothetical case studies, which demonstrates its applicability to various types of cities, and its ability to quantify and compare water supply resilience. The analysis of a range of urban water systems provides valuable insights into guiding more sustainable responses for maintaining the resilience of urban water supply around the globe, by showing how unsustainable responses risk the loss of resilience. We suggest that the same model can be generalized to represent other types of urban infrastructure service systems with different parameterizations.

Hydroclimatic Controls on Agroecosystem Resiliency in the Northern High Plains

NASA Astrophysics Data System (ADS)

Munoz-Arriola, F.; Amaranto, A.; Solomatine, D.; Corzo, G.

2016-12-01

Water-controlled ecosystems play a critical role in sustaining intensive food production. More frequent and intense droughts and extreme precipitation challenge genetic progresses to increase crop yields. This work aims to identify the agroecosystem's resiliency to droughts and extreme precipitation in the Northern High Plains (NHP). NHP is characterized by its extensive use of groundwater to fulfill crop irrigation requirements. Groundwater "subsidizes" water deficits and supports intensification of crop production. However, it is unclear how sensitive are agroecosystems to hydroclimatological variations at large-scale, which may affect water discharge and recharge at basin scale and crop production at field scale. Our objective is to develop diagnostic and prognostic conceptual models for groundwater withdrawals in response to climate variability and consumptive use of water. The present study is located in the irrigated agricultural areas of the NHP. We use observed changes in the water table as tracers to changes natural forcing (i.e. observed precipitation) and anthropogenic water demands (i.e. simulated evapotranspiration) though the development of two different diagnostic/prognostic models using Artificial Neural Network (ANN) and Support Vector Machine (SVM). Water-table data was obtained from the Nebraska Geological Survey, and gridded daily hydroclimatic data from Livneh et al (2015), which together with MODIS-LAI provided the inputs for a Variable Infiltration Capacity model to simulate evapotranspiration at a 1/16th degree resolution. A regionalization procedure based on K-Clustering was applied to precipitation data (1950-2013) to identify areas of common and natural variability. Inconsistent output and input sampling frequencies used a time adaptation algorithm to assist the training of the ANN and SVM models. Results showed that both the ANN and the SVM diagnose and predicted ground water. Selected dry and wet (identified Extreme-Precipitation-Event) years are evaluated to isolate hydroclimate and water management drivers and resilient agroecosystems. This methodology will contribute to identify areas of physical vulnerability and agroecosystem resiliency.

Selective speciation and determination of inorganic arsenic in water, food and biological samples.

PubMed

Tuzen, Mustafa; Saygi, Kadriye Ozlem; Karaman, Isa; Soylak, Mustafa

2010-01-01

A procedure for the speciation of arsenic(III) and arsenic(V) in natural water samples has been established in the presented work. Arsenic(III) ions were quantitatively recovered on Alternaria solani coated Diaion HP-2MG resin at pH 7, while the recoveries of arsenic(V) was below 10%. Arsenic(V) in the mixing solution containing As(III) and As(V) was reduced by using KI and L(+) ascorbic acid solution, then the procedure was applied to determination of total arsenic. Arsenic(V) was calculated as the difference between the total arsenic content and As(III) content. The determination of arsenic was performed by using hydride generation atomic absorption spectrometry. The influences of some alkali, earth alkali and transition metals on the biosorption of arsenic(III) were investigated. The preconcentration factor was 35. The detection limits for As(III) (N=20, k=3) was found as 11 ng L(-1). The relative standard deviation and relative error of the determinations were found to be lower than 7% and 4%, respectively. The accuracy of the method was confirmed with certified reference materials. The method was successively applied for the determination and speciation of inorganic arsenic in water, food and biological samples. Copyright 2009 Elsevier Ltd. All rights reserved.

Building a new regulatory paradigm for coastal and estuarine acidification

NASA Astrophysics Data System (ADS)

Brodeur, J.; Cai, W. J.

2016-02-01

Ocean acidification regulation generally falls under the authority of the Clean Water Act (CWA, P.L. 92-500). The CWA has been a powerful tool to improve the country's water quality, but it is most adept at addressing point-source pollutants and contaminants. It requires policymakers to determine "natural levels" of the target pollutant and to attribute changes in water quality to a specific source, both of which are tough or impossible tests for the diffuse carbon imbalance that is associated with ocean acidification, even if we could easily identify the threshold level for harm to organisms (Boehm, 2015). Even where regulators have tried to apply CWA to address acidification, they have been confronted by a lack of baseline data, an inability to specifically identify sources within their jurisdiction, and the fact that existing water quality standards do not capture the impairments that are associated with ocean acidification (Cooley, 2015). In fact, there was a lawsuit brought by the Center for Biological Diversity against the U.S. Environmental Protection Agency (EPA) alleging the agency had failure to regulate this issue. In the end, the courts sided with the EPA, and it continues to struggle with how to use pH and/or saturation state to define a point at which a water body becomes impaired and a threat to sea-life and natural resources. We present an analysis of the complexities related to regulating ocean acidification, the history of work in this area, and suggest a solution that can be tailored to fit unique coastal and estuarine characteristics.

Building a new regulatory paradigm for coastal and estuarine acidification

NASA Astrophysics Data System (ADS)

Brodeur, J.; Cai, W. J.

2016-12-01

Ocean acidification regulation generally falls under the authority of the Clean Water Act (CWA, P.L. 92-500). The CWA has been a powerful tool to improve the country's water quality, but it is most adept at addressing point-source pollutants and contaminants. It requires policymakers to determine "natural levels" of the target pollutant and to attribute changes in water quality to a specific source, both of which are tough or impossible tests for the diffuse carbon imbalance that is associated with ocean acidification, even if we could easily identify the threshold level for harm to organisms (Boehm, 2015). Even where regulators have tried to apply CWA to address acidification, they have been confronted by a lack of baseline data, an inability to specifically identify sources within their jurisdiction, and the fact that existing water quality standards do not capture the impairments that are associated with ocean acidification (Cooley, 2015). In fact, there was a lawsuit brought by the Center for Biological Diversity against the U.S. Environmental Protection Agency (EPA) alleging the agency had failure to regulate this issue. In the end, the courts sided with the EPA, and it continues to struggle with how to use pH and/or saturation state to define a point at which a water body becomes impaired and a threat to sea-life and natural resources. We present an analysis of the complexities related to regulating ocean acidification, the history of work in this area, and suggest a solution that can be tailored to fit unique coastal and estuarine characteristics.

The effect of water contamination on the dew-point temperature scale realization with humidity generators

NASA Astrophysics Data System (ADS)

Vilbaste, M.; Heinonen, M.; Saks, O.; Leito, I.

2013-08-01

The purpose of this paper is to study the effect of contaminated water in the context of humidity generators. Investigation of different methods to determine the drop in dew-point temperature due to contamination and experiments on actual contamination rates are reported. Different methods for calculating the dew-point temperature effect from electrical conductivity and density measurements are studied with high-purity water and aqueous solutions of NaCl and LiCl. The outcomes of the calculation methods are compared with the results of direct humidity measurements. The results show that the often applied Raoult's law based calculation method is in good agreement with other methods. For studying actual contamination, water samples were kept in glass, plastic, copper and stainless-steel vessels for up to 13 months to investigate natural ionic and organic contamination in vessels with different wall materials. The amount of ionic contamination was found to be higher in copper and glass vessels than in stainless-steel and plastic vessels. The amount of organic contamination was found to be highest in the plastic vessel. In all the cases, however, the corresponding drop in dew-point temperature due to natural contamination was found to be below 0.1 mK. The largest rate of change of dew-point temperature was 26 µK/month. Thus, if proper cleanness is maintained in a humidity generator the effect of contamination of water in the saturator is insignificant compared with the major uncertainty components even in the most accurate generators today.

Reduction of Turbidity of Water Using Locally Available Natural Coagulants

PubMed Central

Asrafuzzaman, Md.; Fakhruddin, A. N. M.; Hossain, Md. Alamgir

2011-01-01

Turbidity imparts a great problem in water treatment. Moringa oleifera, Cicer arietinum, and Dolichos lablab were used as locally available natural coagulants in this study to reduce turbidity of synthetic water. The tests were carried out, using artificial turbid water with conventional jar test apparatus. Optimum mixing intensity and duration were determined. After dosing water-soluble extracts of Moringa oleifera, Cicer arietinum, and Dolichos lablab reduced turbidity to 5.9, 3.9, and 11.1 nephelometric turbidity unit (NTU), respectively, from 100 NTU and 5, 3.3, and 9.5, NTU, respectively, after dosing and filtration. Natural coagulants worked better with high, turbid, water compare to medium, or low, turbid, water. Highest turbidity reduction efficiency (95.89%) was found with Cicer arietinum. About 89 to 96% total coliform reduction were also found with natural coagulant treatment of turbid water. Using locally available natural coagulants, suitable, easier, and environment friendly options for water treatment were observed. PMID:23724307

Membrane-based microchannel device for continuous quantitative extraction of dissolved free sulfide from water and from oil.

PubMed

Toda, Kei; Ebisu, Yuki; Hirota, Kazutoshi; Ohira, Shin-Ichi

2012-09-05

Underground fluids are important natural sources of drinking water, geothermal energy, and oil-based fuels. To facilitate the surveying of such underground fluids, a novel microchannel extraction device was investigated for in-line continuous analysis and flow injection analysis of sulfide levels in water and in oil. Of the four designs investigated, the honeycomb-patterned microchannel extraction (HMCE) device was found to offer the most effective liquid-liquid extraction. In the HMCE device, a thin silicone membrane was sandwiched between two polydimethylsiloxane plates in which honeycomb-patterned microchannels had been fabricated. The identical patterns on the two plates were accurately aligned. The extracted sulfide was detected by quenching monitoring of fluorescein mercuric acetate (FMA). The sulfide extraction efficiencies from water and oil samples of the HMCE device and of three other designs (two annular and one rectangular channel) were examined theoretically and experimentally. The best performance was obtained with the HMCE device because of its thin sample layer (small diffusion distance) and large interface area. Quantitative extraction from both water and oil could be obtained using the HMCE device. The estimated limit of detection for continuous monitoring was 0.05 μM, and sulfide concentrations in the range of 0.15-10 μM could be determined when the acceptor was 5 μM FMA alkaline solution. The method was applied to natural water analysis using flow injection mode, and the data agreed with those obtained using headspace gas chromatography-flame photometric detection. The analysis of hydrogen sulfide levels in prepared oil samples was also performed. The proposed device is expected to be used for real time survey of oil wells and groundwater wells. Copyright © 2012 Elsevier B.V. All rights reserved.