bluuebunny/crossref_metadata_2025_split huggingface dataset:
Water Conservation for Sustainable Agriculture
Authors: Shen1 Yanjun , Pei2 Hongwei 
Published: December 2019

AbstractAgriculture not only consumes 70% of global freshwater and 90% of global groundwater but also causes a lot of environmental problems, such as drying up of rivers, groundwater depletion and pollution. Thus, water conservation is considered a necessary requirement if we are to feed the booming global population by supporting sustainable agriculture. Generally, increasing water supply (e.g. interbasin water transfer, artificial precipitation) and enhancing water use efficiency via water‐saving technologies (e.g. dripping irrigation, mulching, deficit irrigation, and water‐saving cultivars) are the main ways to solve water resources shortage in agriculture. In practice, water use efficiency in different scales is measured to help people to realize the importance of the process of water consumption and to enhance water productivity. Water transfer and other human actions also aim to sustain the water demand of human society. However, overuse of water resources is still threatening human lives in most countries globally, and we need to employ water‐saving technologies, increase reuse of water continually, and also mind the risks from agricultural intensification (irrigation and fertilization) and climate change on food production.
Nuclear Wastes in the United States
Authors: King1 Judy Y. , Hylko2 James M. 
Published: December 2019

Abstract
The nuclear fuel cycle in the United States began during World War II and was associated with the Manhattan Project. The presence of nuclear wastes has been under review and control by the federal government since that era.
The techniques for treating liquid wastes are well established and effective to meet the current government standards. The future treatment and handling of waste residuals from the nuclear industry elements (mining, beneficiation, use and disposal) require additional study and, potentially, different technical solutions to meet health and exposure standards.
Hydrology and Climate Change in Pacific and Similar Regions: Insights from Hawaii
Authors: Leta Olkeba Tolessa , El‐Kadi Aly I. 
Published: December 2019

AbstractPopulation growth in Hawaii is causing major stress on available water resources. In addition, it is anticipated that climate change will lead to challenges concerning freshwater availability and negatively affect related natural habitats. This article reviews the consequences of changing rainfall, temperature, and solar radiation on groundwater resources. It also addresses the effect of sea level rise on the inundation of the coastal zone areas. Studies have shown that Hawaii is generally expected to face an overall decline in rainfall amount, increase in temperature, with a higher rate at elevated altitudes, and amplified rate of sea level rise. Such changes are projected to threaten groundwater availability and sustainability, cause recurrent hydrological droughts, and groundwater inundation and flooding of coastal zones. Nearshore problems can include damages to coastal infrastructures, salt‐water intrusion, and reduction in groundwater quality, and loss of aquatic habitats. Further, these impacts are anticipated to be amplified toward the end of this century. Owing to limited groundwater resource over the Islands, water use restrictions are most probably to happen with expected increases in agricultural water and other water‐use demands. Therefore, utilizing adaptation measures to climate change for Hawaii and similar Islands are of critical importance.
Using Citizen Science to Raise Public Awareness and Engagement with Water Issues
Authors: Araya Yoseph 
Published: December 2019

Abstract
The world faces increasing freshwater supply challenges, fueled partly by rising demand as well as mismanagement of existing resources. This necessitates an aware and engaged public as well as sound water resource management that is supported by data‐driven scientific knowledge. Often the public lacks sufficient awareness to participate in resource management; and too often scientists and decision‐makers struggle to obtain sufficient good quality data (across time and space scales) to effect change. Citizen science offers a powerful tool to tackle both these challenges by providing efficient and effective ways to obtain useful data while educating citizens about water issues. This article uses examples to describe the role of citizen science, the opportunities available for engagement and identifies criteria for success.
European Marine Biodiversity Observatory Systems
Authors: Hummel Christiaan , Hummel Herman , van Avesaath Pim , Magni Paolo 
Published: December 2019

Abstract
This article provides an overview of European Marine Biodiversity Observatory Systems. It explains why more attention should be focused on marine biodiversity and raises concern about the understudied marine realm. It builds on a historical perspective of the creation of networks of marine stations, as well as the need of harmonization among them. Finally, a few examples of successful projects and results obtained are given, followed by concluding remarks from the current situation to a future perspective.
Kinetics of Halogenated Disinfection By‐Products Formation in Chlorinated Seawater
Authors: Elsaid Khaled , Batchelor Bill , Abdel‐Wahab Ahmed 
Published: December 2019

AbstractThe use of seawater as a source for potable water supply after desalination, and in once‐through industrial cooling is a common practice in many parts of the world that have limited fresh‐water resources. A disinfectant (commonly chlorine) is added to the seawater to control biofouling in desalination or cooling systems. The added chlorine reacts with bromide and other compounds present in seawater to produce a wide range of chemical oxidants. Regrettably, reactions between the residual oxidants and natural organic matter present in seawater lead to the formation of halogenated organic compounds that have detrimental effects on human health and the environment. Of particular note is the fact that brominated forms of disinfectants are more effective in producing halogenated organic by‐products than chlorinated forms. In this article, the kinetics of residual oxidants decay and formation of halogenated disinfection by‐products (DBPs) in seawater is discussed and explained in detail. A kinetic model is developed, which includes rate constants for all base reactions and stoichiometric coefficients for all halogenated (DBPs) formed by these base reactions. The model is calibrated using experimental results to obtain the different kinetic rate coefficients.
Retardation
Authors: Holzbecher Ekkehard 
Published: December 2019

Abstract
The transport of chemical or other type species in a flow field may be retarded in relation to that of mean fluid particles. Measurements may indicate that the species in question has a lower velocity than the fluid. Such retardation is observed in natural and artificial systems of various types. In the different environments, different processes are responsible for the observed phenomenon. They all have in common that for a certain time period, a part of the substances are not participating in the transport, but are stagnant or almost stagnant. The mathematical description is outlined, which is common for various cases and that leads to the introduction of a retardation factor as a measure for the effect. It is shown that retardation cannot be understood in a strict sense as a simple prolongation of the timescale. Finally, also thermal retardation is covered analogously to solute retardation.
Potential Flow
Authors: Holzbecher Ekkehard 
Published: December 2019

AbstractThe concept of potential flow is derived from a classical mathematical theory that can be formulated in terms of complex analysis (in 2D). The basic definitions of this classical theory are presented, followed by the presentation of elemental potential flows. The powerful technique of superposition allows the construction of solutions with specific properties, concerning sinks, sources, rotations, boundary conditions, etc. The technique of mapping enables the construction of solutions in irregular domains from solutions in simpler geometries. The field of groundwater and porous media flow is taken as an example for a brief demonstration of how potential flow solutions are used in applied problems.
Wind Generation of Waves
Authors: Hristov Tihomir 
Published: December 2019

Abstract
The mechanism responsible for the generation of ocean waves by wind is described. The physical analysis here develops from first principles and requires only the well‐verified premise of small‐slope waves, ensured by the phenomenon of wave breaking. The wind generated waves occur from the coherent interaction between two distinct and random fluid‐mechanical fields – the turbulent atmospheric flow and the compliant ocean surface. The dynamic and statistical patterns of the wave‐coherent air motion as well as the dynamic significance of the critical height in the air flow are outlined. The phase discontinuity of the wave‐coherent air flow at the critical height is specifically discussed, as it is among the testable predictions of the theory. Experimental evidence in support of wind wave generation through wave‐coherent flow with a critical layer is presented.
Wastewater Treatment: Mathematical Modeling
Authors: Dudley Jeremy 
Published: December 2019

Abstract
In 1985, mathematical modeling in wastewater was described as having no real value and that the use of existing rules of thumb and loading rates was sufficient to design treatment systems. Two years later, the release of the IWA Activated Sludge Model No. 1 kick‐started the wide use of mathematical modeling for activated sludge systems. Since then modeling has seen wider use, for design and operation and covering more process units. This article provides a summary of the more commonly available models. There is a brief summary of literature references for solving differential equations, and for applying the unit process models as part of an integrated flowsheet for whole treatment trains.
Phosphorus and the Baltic Sea: Sustainable Management
Authors: Berthold Maximilian , Nausch Günther , von Weber Mario , Koch Stefan , Kahle Petra , Lennartz Bernd , Tränckner Jens , Buczko Uwe , Tonn Claudia , Ekardt Felix , Bathmann Ulrich 
Published: December 2019

AbstractWorldwide, many aquatic systems are under anthropogenic induced pressure by elevated nutrient inputs. In particular, increased nitrogen and phosphorus usage have led to human‐induced eutrophication (including cyanobacterial blooms and hypoxia) of all kinds of water bodies. Associated pressures need to be described, and diminished, in order to reach a sustainable human usage of ecosystems. The Baltic Sea is a model system, as it is prone to Global Change, and is strongly influenced by human actions and shows recurrent cyanobacterial blooms and hypoxia. There have already been several actions to ameliorate these problems, e.g. by reducing the inflow of phosphorus. However, even the strongest possible reductions are currently not enough to restore the Baltic Sea. Coastal water bodies are still highly eutrophic, and the catchment area is affected by permanent runoff‐events from adjacent land. Furthermore, new approaches are needed to improve the efficiency of water treatment plants. On the other side, legislation is sometimes inefficient on a local scale. Such problems can only be solved in multidisciplinary approaches that include environmental, engineering and social sciences. Here, we present an overview of recent research with emphasis on phosphorus and its flows and controls into the Baltic Sea from the German catchment area.image
Undergraduate Geoscience Education in Environmental and Water Sciences
Authors: Arthurs Leilani A. 
Published: December 2019

Abstract

The landscape of undergraduate geoscience education in the United States is changing, and existing research supports a shift in educational practices away from traditional lecture toward more active learning. Translating the general best practice of active learning into domain‐specific instruction (e.g. environmental and water sciences domains) remains a challenge. Findings from emerging areas of undergraduate geoscience education research and geocognition research can help to meet this challenge. In the meantime, instructors of undergraduate environmental and water sciences courses can access several repositories for class activities and assessments. These include the
Journal for Geoscience Education
,
Digital Library for Earth System Education
,
Science Education Resource Center
,
On the Cutting Edge: Strong Undergraduate Geoscience Teaching
, and
Teaching about Earth for a Sustainable Future
. These resources can help advance individual geoscience instructor efforts to transform their courses and, thereby, transform the landscape of undergraduate geoscience education.
Water Well Drilling Methods
Authors: Jacobs James A. 
Published: December 2019

Abstract
Water well installation, for domestic or public water supply purposes, groundwater monitoring projects or for irrigation involves a variety of drilling techniques, depending on subsurface conditions, groundwater depth, access, and other factors. The three most common drilling methods for potable water supply wells are rotary drilling, auger drilling, and cable tool drilling. More recently sonic drilling has been used in certain for potable water well construction. The main challenge in drilling is to drive the drill string to the target depth while removing the drill cuttings and maintaining borehole wall integrity. Each drilling location has site‐specific surface and subsurface conditions, selecting the optimal drilling method is critical to installing a successful well. Drilling method selection relates to a variety of factors, including rig and crew availability, site accessibility, time and cost of project, sediment type (consolidated rock or unconsolidated soils), special drilling problems (unconsolidated sediments and soils, pressurized saturated sands, lost circulation zones, cobbles, and boulders), soil/rock sample type desired (undisturbed vs. disturbed), and sample integrity.
For contaminant studies and environmental projects, monitoring and remediation water wells (and vapor wells) are installed, which frequently relate to chemical spillage on or near the surface. The most common drilling method for installing shallow monitoring and remediation wells is hollow stem auger drilling which works well in soil and unconsolidated sediments, and soft rocks. Hard rock drilling required for environmental projects have used air rotary or cable tool drilling rigs, and to a lesser degree, mud rotary drilling rigs. Soil/rock, soil vapor, and groundwater collection and integrity are critical for environmental projects where depth discrete sampling is common as well as vadose zone sampling. The vadose zone, also called the unsaturated zone, includes the zone immediately above the water table to the surface. The lower vadose zone includes the capillary fringe, the zone where water is drawn upward by capillary force. The water table is the top of the saturated or phreatic zone within the aquifer. Other drilling methods are used for contaminant studies, including direct push and sonic drilling.
Cobalt in Groundwater: Chemical Behavior and Treatment
Authors: Jacobs James A. 
Published: December 2019

Abstract

Cobalt occurs naturally in ores with oxygen as cobalt oxide and with other elements and has characteristics similar to the properties associated with iron and nickel. Cobalt has an atomic number of 27 and there is only one stable isotope of cobalt, having an atomic mass number of 59. There are many unstable or radioactive isotopes of Cobalt, two of which are important commercially: cobalt‐60 (Co‐60 or
60
Co) and cobalt‐57 (Co‐57 or
57
Co). All isotopes of cobalt behave the same chemically. Cobalt enters the environment through both natural processes and anthropogenic activities. The metal has been known to be contained within windblown dust, seawater spray, forest fires, and volcanic eruptions. When deposited as part of particulate, the cobalt can be leached by rainwater taking the cobalt into the vadose zone and possibly deeper into shallow groundwater. Soil near cobalt ore deposits, phosphate rocks or other ore smelting facilities, may contain high levels of cobalt as well as soils and dust generated from highway and airport traffic and other industrial activities creating air pollution. Cobalt has also been known to be released into the air from a variety of common industrial uses or processes, including coal‐fired power plants, mining, and processing of cobalt ores, production and use of cobalt alloys and chemicals, vehicular exhaust and incinerators Remediation of cobalt is similar to other metals where cobalt in a reduced state as cobalt sulfide precipitates out of groundwater in the presence of a strong reducing agent such as sodium metabisulfite, calcium polysulfide or ferrous sulfate. Permeable reactive barriers with zero‐valent iron (ZVI) and other amendments have also been used to create reducing conditions for metal precipitation.
Soil and Groundwater Sampling Methods
Authors: Jacobs James A. 
Published: December 2019

Abstract
Groundwater assessment for environmental projects involves significant soil sampling to evaluate hydrologic and lithologic conditions. Soil samples in environmental investigations are typically collected at a minimum of 1–2 m and at changes of lithology or obvious signs of contamination, based on soil staining or discoloration of the soil or in the case of volatile organic compounds, organic vapor readings. Continuous coring is recommended for a minimum of at least one soil boring per site to characterize the subsurface adequately. Soil samples collected in the vadose zone above the water table are in the unsaturated zone. Groundwater is moving generally vertically, and some horizontal movement is caused by rootlets, faults, impermeable layers, or other conduits. Soil samples collected within the capillary fringe or below the groundwater table are in the saturated zone.
The capillary fringe moves up and down with seasonal variations of the groundwater table. Petroleum hydrocarbons move vertically from the source, such as an underground storage tank, through the vadose zone. As the hydrocarbons move vertically through the lithologic section, in general, the finer grained the soil, the greater the lateral spreading of the contaminant. The capillary fringe, within the saturated zone, is the zone immediately above the water table, where water is drawn upward by capillary attraction. Owing to irregularities in pore sizes among the grains of sediment, the capillary water does not rise to an even height above the water table but rather forms an irregular capillary fringe. The capillary fringe is higher in fine‐grained soils such as a fine silt than in coarse‐grained soil such as a gravel due to greater tensions created by the smaller pore openings. The capillary fringe can be the zone of direct evaporation of groundwater if the water table is close enough to the surface. This article is an updated version of an earlier article from 2005.
Watershed Nitrogen Budgets
Authors: Fisher Thomas R. , Fox Rebecca J. , Knee Karen L. , Jordan Thomas E. 
Published: December 2019

AbstractNitrogen (N) limits primary production in many terrestrial and aquatic systems, a paradox in a world with 78% N2in the atmosphere. Nitrogen has nine valence states ranging from reduced (−3, NH3, amino groups) to oxidized (+5, NO3−), creating opportunities for energy‐yielding microbial transformations of N along redox gradients. Anthropogenic N additions increase plant production and food supplies on land, but simultaneously result in contaminated drinking water, algal blooms, and hypoxia in adjacent waters. Management of these problems is often informed by N flux measurements and budgets. However, in watershed N budgets, measured N inputs typically exceed measured stream output, leading to the conundrum of “missing N.” The missing N is either stored internally within watersheds or lost to the atmosphere as N gases (NH3, N2, N2O, NO). Measurements of both N storage and N gas fluxes have accounted for the missing N in a few cases, but there are few examples of complete N budgets because measurements of the spatially/temporally heterogeneous N pools and N gas fluxes are difficult at the watershed scale. Therefore, investigating watershed N budgets remains a fruitful area for future research to control the deleterious effects of anthropogenic N in aquatic systems.
Xenobiotic Chemicals: Emerging Contaminants and Recalcitrant Compounds in Groundwater
Authors: Jacobs James A. , Mohr Thomas K.G. 
Published: December 2019

Abstract
Xenobiotic contaminants released to soil and groundwater are classified as recalcitrant when they are minimally degraded by common biodegradation and abiotic pathways, and as emerging contaminants when the contaminants meet several criteria, such as (i) potentially harmful to human health, (ii) newly identified due to advances in laboratory analytical capabilities or general awareness, (iii) poorly removed by existing treatment technologies.

In situ
microbial colonies have evolved over time to degrade naturally occurring compounds by exuding enzymes and using various available compounds for either a terminal electron acceptor or as a food source. Xenobiotic chemicals (anthropogenic organic compounds and their reaction products) have chemical characteristics and bond structures which are less susceptible to break down under normal subsurface biogeochemical conditions. Therefore, attenuation of xenobiotic compounds from biodegradation by indigenous soil microbes generally does not occur. Although the source for xenobiotic chemicals relates to synthetic production, the compounds which become emerging contaminants or recalcitrant compounds can originate from a range of uses and activities, from a stabilizing chemical added to an industrial solvent, a reaction product from an industrial process, or a residual waste mixed in and sold as part of a commercial industrial chemical product. More emerging contaminants have been identified in recent years due to advances in laboratory chemical analytical methods, improved understanding of the composition of waste mixtures, and improved monitoring and sampling.
Organic Compounds in Water and Organic Sorption to Minerals
Authors: Maurice Patricia A. 
Published: December 2019

AbstractNatural organic matter is ubiquitous in aquatic environments and can affect water pH and color. Man‐made organic contaminants are also widespread, ranging from pesticides and herbicides to petroleum products and even pharmaceuticals. This article provides brief background material on aqueous organic chemistry followed by discussion of several different groups of organic compounds, including comments on their sorption to minerals.