bluuebunny/crossref_metadata_2025_split huggingface dataset:
Freshwater
Authors: Kazemi Gholam A. 
Published: April 2005

Abstract

Water is an important solvent and is sometimes called the universal solvent (1). It dissolves, to the extent possible, the material with which it comes in contact. Salinity is a measure of various constituents dissolved in water, including solids, liquids, and gases. Total dissolved solids (TDS), another form of expressing the amount of dissolved ingredients in water, is the sum of total solids that have been dissolved in water [note that TDS at 180°C = Sum of ions + SiO
2
− 0.5082 × mg/l HCO
3
; (2)]. However, many references do not differentiate between TDS and salinity because the absolute majority of the dissolved constituents of water are usually the solids. Both parameters have units of mg/l or ppm. These two units, ppm and mg/l, are almost the same except for high salinity waters for which 1 mg/l = 1 ppm × density of water. The salinity of groundwater ranges from 25 mg/l in quartzite springs to more than 300,000 mg/l in brine (3), and the salinities of distilled water, River Murray in South Australia, seawater, and the Dead Sea are 0, 553, 35,000, and 385,000 mg/l, respectively (4).
Iron
Authors: Roy William R. 
Published: April 2005

Abstract

The average concentration of iron in the earth's crust is about 5%, and it occurs in a wide variety of oxide, carbonate, silicate, and sulfide compounds either as metallic ores or in rock‐forming minerals. Iron also occurs naturally in water from the dissolution of iron‐containing minerals. Iron in water can occur in a dissolved form, a colloidal form that is combined with organic matter, and as suspended, iron‐containing particles. Dissolved iron occurs in water in two oxidation states: ferrous iron, Fe (II), and ferric iron, Fe (III). In solution, iron can occur as a cation (Fe
2+
) and in combination with other ions to form complexes and neutral ion pairs. Iron does not generally occur as the trivalent cation (Fe
3+
) in significant concentrations in water. Trivalent iron generally exists in combination with other constituents. Depending on the occurrence of anions, such as sulfate, carbonate, and phosphate, and the pH and reduction‐oxidation potential (
E
h
), the major iron species found in natural waters include a sulfate complex (FeSO
4
0
), a carbonate form [Fe(HCO
3
)
2
], phosphate complexes (FeHPO
4
0
, FeH
2
PO
4
+
), and various hydroxide species such as FeOH
+
, Fe(OH)
2
+
, Fe(OH)
3
0
, Fe(OH)
4
−
, and FeOH
2+
. The relative proportion of ferrous iron and ferric iron depends on the
E
h
of the water; ferrous iron is the dominant form in oxygen‐poor water (reducing conditions). In oxygen‐rich water (oxidizing conditions), ferric forms of iron dominate.
Isotope Fractionation
Authors: Kazemi Gholam A. 
Published: April 2005

Abstract
In general chemistry, fractionation is the separation of a mixture, usually of chemically related components, into fractions that possess different properties. A mixture of liquids having different boiling points, may be separated by collecting fractions that boil at different temperatures in a fractionating column. This is a long, vertical column containing plates or bubble caps attached to a still. As a consequence of internal reflux, a gradual separation occurs between high and low boiling point fractions of the liquid mixture.

In hydrochemistry, the fractionation factor is a ratio which shows the depletion or addition of ions in rainwater compared to seawater (2). In other words, the fractionation factor is the ratio of two ions in rainwater to the ratio of the same ions in seawater. For example, for Cl
−
relative to Na
+
, the fractionation factor
F
Na
is:(2)

urn:x-wiley:9780471478447:media:pc336:xm1

In this equation, the units of concentration can be mg/l, mmol/l, meq/l, etc.
Silica in Natural Waters
Authors: Ning Robert Y. 
Published: April 2005

AbstractSilica and silicates are generic names given to the family of silicon dioxide compounds derived from the dehydration–polymerization of silicic acid [Si(OH)4]. Silicic acid, variously called orthosilicic acid, monosilicic acid, or silicic acid monomer, is a weak tetravalent acid that has pKavalues of 9.9, 11.8, and 12. Although silicic acid is prevalent in natural waters and is readily available from acidification of commercial crystalline sodium silicate or metasilicate, it has a great propensity to polymerize by dehydration to form Si–O–Si anhydride bonds:urn:x-wiley:9780471478447:media:pc478:xm1Thus silicon dioxide (SiO2, silica) is the final and most stable product in normal conditions of silico‐oxygen acid polymerization. The molecule of silica represented by the formula SiO2is polymeric and is more accurately represented by the formula (SiO2)n, where n is a large number.
Soft Water
Authors: Kazemi Gholam A. 
Published: April 2005

AbstractThe author, here, wishes to draw the reader's attention to one other point and pose a question as well. He believes that “softness” would have had an identical application and a similar meaning to hardness if it would have been there. Therefore, it is interesting to speculate as to what was the rationale for use of the term “hardness”, not softness. One reason might be that hard water is generally easier to notice because of its unwanted and disappointing characteristics and our predecessors looked for something to describe it. In other words, the term hardness was created to explain easily noticeable hard water, not to describe soft water. This is why there is no such practice as water hardening, changing soft water to hard water, in contrast to the well‐established exercise of water softening which changes hard waters to soft waters.The definition of soft water varies slightly among researchers. Based on Table 1, soft water is defined as water whose hardness is less than 60 or 75 mg CaCO3/L. This means that waters with less than 15 mg Ca2+/L and 10 mg Mg2+/L are soft; higher concentrations in waters belong to the other categories such as hard water or very hard water. However, some researchers argue that there is no exact definition for determining soft or hard water because it depends, at least partially, on what one is accustomed to. What is soft water for one person, may be moderately hard for another and vice versa.
Strontium Isotopes in Water and Rock
Authors: Kazemi Gholam A. 
Published: April 2005

Abstract

The Sr isotopic ratio in natural water reflects the contribution made by various minerals as they dissolve in water. Rivers are the major provider of strontium to the oceans and define, to a great extent, the marine
87
Sr/
86
Sr ratio. Strontium in rivers is mainly derived from two end members: limestone and evaporites as one end member (high Sr and low
87
Sr/
86
Sr ratio of 0.706–0.709) and silicate rocks as the other end member that are low in Sr and have a higher
87
Sr/
86
Sr ratio. Processes such as atmospheric deposition, cation exchange, and biological cycling, too, influence the Sr isotope ratio in water. However, unless there have been recent anthropogenic or natural disturbances, annual gains or losses of Sr from cation exchange and biological pool should be minimal.
Carbonate in Natural Waters
Authors: Ning Robert Y. 
Published: April 2005

AbstractCarbonate is the divalent anion resulting from complete neutralization of carbonic acid. In natural waters, it is in dynamic equilibrium with carbon dioxide gas, carbonic acid, bicarbonate anion, and solid forms of insoluble carbonate minerals—mainly calcium carbonate:urn:x-wiley:9780471478447:media:pc81:xm1Various aspects of the CO2–carbonate systems in natural waters have been extensively reviewed. Practical interests lie in the areas of geochemistry, biochemistry, water treatment and usage, and environment.
Submerged Aquatic Plants Affect Water Quality in Lakes
Authors: Havens Karl E. 
Published: April 2005

AbstractThis chapter addresses four questions:What types of submerged plants occur in lakes, and how does type of plant relate to water quality benefits?What factors control the biomass and spatial extent of submerged plants?What are the processes whereby plants affect lake water quality, in particular, the concentrations of nutrients, turbidity, and the occurrence of noxious algae?How can lakes be managed to promote the development of submerged plants that will help to improve water quality?
Surface Runoff and Subsurface Drainage
Authors: Holden Joseph 
Published: April 2005

Abstract
Runoff is the movement of water across or through the land surface. Sometimes, the word runoff is used simply to refer to river discharge. However, there are many different types of runoff, including overland flow (surface runoff) or throughflow (subsurface runoff, sometimes also called interflow). Precipitation can either hit the surface of the hillslope directly or be intercepted by vegetation. This intercepted water can be stored on leaves and tree trunks which shelter the ground beneath, or it can trickle down to reach the surface via stem flow. There are then two possibilities for direct precipitation or stem flow, once it reaches the hillslope, either to infiltrate into the soil or to pond up and flow over the surface as overland flow. Water that enters the soil may percolate down or move laterally through the soil as throughflow, or it may return to the surface where the soil becomes saturated. The following sections provide details on each of the main interlinked overland flow and subsurface drainage mechanisms.
Trace Elements in Water, Sediment, and Aquatic Biota—Effects of Biology and Human Activity
Authors: Priyadarshi Nitish 
Published: April 2005

AbstractTrace elements are defined here as those elements that generally occur in water at concentrations of less than 1 mg/L.Trace elements enter the aquatic environment in small soil particles that are redistributed during runoff as suspended particles in streams, lakes, and coastal marine locations. Trace elements in water are important; they are toxic to humans and aquatic life in excess, and they accumulate in food chains. Trace element activity in aquatic systems depends on the element species formed by natural hydrodynamic, chemical, and biological forces.The concentrations of trace elements in water are often much lower than would be expected from either equilibrium solubility calculations or supply to water from various sources. The most common reason for the low concentrations is adsorption of elements onto a solid phase.
Cultural Eutrophication
Authors: Priyadarshi Nitish 
Published: April 2005

Abstract
The phrase “cultural eutrophication” (=cultural enrichment) is becoming widely used to denote organic pollution resulting from human activities. Humans, through their various cultural activities, have greatly accelerated this process in thousands of lakes around the globe. Cultural or anthropogenic “eutrophication” is water pollution caused by excessive plant nutrients. Increased productivity in an aquatic system sometimes can be beneficial. Fish and other desirable species may grow faster, providing a welcome food source (1). Eutrophication produces “blooms” of algae or thick growths of aquatic plants stimulated by elevated phosphorus or nitrogen levels. There has been some uncertainty as to whether algal blooms result from increased concentrations of nitrate or phosphate or from some other cause. It is now commonly accepted that algal growth in fresh waters is generally restricted by phosphate concentrations, whereas in marine waters, it is restricted by nitrate concentration (2). In freshwaters, the nitrate concentration might, however, influence the kinds of algae that grow, some of which taint in drinking water or are toxic to animals.
Urban Flooding
Authors: Mark Ole 
Published: April 2005

AbstractFlooding in urban areas is an inevitable problem in many cities, and it causes huge costs to the society in structural and nonstructural damage. The problems that arize from urban flooding range from minor ones such as water getting into the basement of a few houses, to major incidents, where large parts of cities are inundated for several days. Most modern cities in the industrialized part of the world usually experience smaller scale local problems due mainly to insufficient capacity in their sewer systems during heavy rainstorms. Cities in other regions, including those in South/Southeast Asia, often have more severe problems because of much heavier local rainfall and lower drainage standards. This situation is continuously getting worse because many cities in the developing countries are growing rapidly these days but do not have the necessary funds to extend and rehabilitate their existing drainage systems.
Urban Water Studies
Authors: Brettschneider Karen D. 
Published: April 2005

Abstract
The urban landscape contains many elements that can alter the water quality of a waterbody. Before development occurs, grass and other natural vegetation hold sediment in place. Streams flowing through undeveloped terrain have no major sources of contaminants, such as bacteria (except for wildlife), that affect contact recreation. There are also no major sources of toxins that could negatively impact humans and wildlife. Development (residential, commercial, industrial, and agricultural, for example) brings issues that have the potential to compromise the character of streams through point source pollution or nonpoint source pollution. The best way to prevent or deal with these issues is to have cooperation among a broad group of stakeholders in each watershed, the area of land (and tributaries) that drains to a particular waterbody. These individuals must work together to develop sound watershed management to protect or to restore the health of the ecosystem of that watershed.
Water Quality in Surburban Watersheds
Authors: Kirby Charles W. 
Published: April 2005

Abstract
The story of water quality in suburban watersheds is primarily that of nonpoint source pollution (NPS). There may be instances where point sources contribute significantly to degraded water quality in suburban areas, such as privately owned or municipal sewage treatment plants, but the most salient characteristic of suburban basins is the conversion of land from a previous forested or agricultural land cover to highly impervious surfaces such as rooftops, roads, and sidewalks.
Alteration of the land surface within a watershed reduces infiltration and increases the proportion of precipitation running directly into the waterways as runoff. The increase in the percentage of impervious surface from urbanization in a stream basin is the primary threat to water quality in suburban areas.
Dilution‐Mixing Zones and Design Flows
Authors: Jha Ramakar , Bhatia K. K. S. , Ojha C. S. P. 
Published: April 2005

AbstractThe possibility that a pollutant will be discharged accidentally or intentionally into a stream/river is a matter of constant concern to those diverting and using water from streams and rivers. It is essential for water resources planners and managers to understand the physical processes involved in a stream/river prior to the implementation of any water resources projects. When a pollutant is discharged into a stream/river, it is subjected to initial dilution immediately due to the density difference between the receiving water and the pollutant.The longitudinal, vertical and two‐dimensional profiles of pollutant concentration indicate the density gradient between the pollutant and the receiving water. After initial dilution, the processes are governed by advection, reaction, and dispersion phenomena that tend to modify the initial pollutant concentration.Advection phenomena represent the downstream transport of a discrete element of the waste load by the stream flow.The reaction phenomena represent the decay of biodegradable materials in the waste under the action of naturally occurring bacteria in the stream. The dispersion phenomena represent that under the influence of turbulence, eddy currents, and similar mixing forces, a discrete element of the waste load tends not to remain intact, but mixes with adjacent upstream and downstream elements. In rivers and streams, the influence of dispersion phenomena is usually relatively small compared with advection and reaction phenomena; however, it can be important in some circumstances.
Fisheries: History, Science, and Management
Authors: Lackey Robert T. 
Published: April 2005

AbstractThe overall goal of fisheries management is to produce sustainable biological, social, and economic benefits from renewable aquatic resources. Fisheries are classified asrenewablebecause the organisms of interest (fish, shellfish, reptiles, amphibians, and marine mammals) usually produce an annual biological surplus that, with judicious management, can be harvested without reducing future productivity. In contrast,nonrenewableresources (oil, coal, iron, and copper) are available in fixed quantities and are not replaced except over geologic time.The benefits that humans gain from a fishery are diverse and may be enumerated in several ways. Most commonly, benefits are computed ascommodityoutput—the weight or number of fish produced. Commodity output may be further split between the animals harvested by capture (fishing for wild animals) or culture (produced as captive animals)—commonly called thecapturefisheries and theculturefisheries, respectively.
Freshwater Colloids
Authors: Lead Jamie R. 
Published: April 2005

Abstract

Colloids exist in all environmental compartments, including the atmosphere where they are termed nanoparticles. In this review we will consider only freshwater colloids, primarily in lakes, rivers and groundwaters, although soils and sediments are also an important source of waterborne colloids. Colloids are defined on the basis of size; at least one dimension is in the range 1 nm–1 µm (10
−9
− 10
−6
m). Below 1 nm is the dissolved or solution phase, and above 1 µm is the particle phase. In practice, this distinction is usually made by operational methods such as ultrafiltration and filtration.
The
A
ral
S
ea Disaster: Environment Issues and Nationalist Tensions
Authors: Lasserre Frederic 
Published: April 2005

Abstract
The village of Muynak was located on an island in the Amu Daria delta in 1956. In 1962, the island had already become a peninsula; in 1970, the sea was 10 km away, then 40 km away in 1980, and 75 km in 1998. The sea bottom became a vast salted desert. In 1987, the retreating sea divided itself in two parts, a small Aral in the north, where the Syr flows, and a large Aral, where the Amu ends its journey when it reaches the sea.

Between 1960 and 1998, the level of the small Aral dropped by 13 meters, and the level of the larger by 18 m. The total sea volume was cut by 78% (5, 6). The vanishing of the sea constitutes an enormous ecological disaster that radically alters the environmental balance in the region:

Vast deposits of salts, nitrates and pesticides spread in large quantities on the industrial crops upstream were formed, deposited by water of the Amu and the Syr. The wind now blows on these desiccated deposits, lifting nearly 40 million tons of toxic sediments each year, and transporting them far inland: this phenomenon poisons the soil, the vegetation, and the inhabitants. The salt fallout can be as high as 500 to 700 kg/ha, which quickly worsens the problem of salt built‐up due to poorly drained and excessive irrigation.
Gully Erosion
Authors: Erskine Wayne D. 
Published: April 2005

AbstractGullies have formed rapidly in many parts of the world during the last 300 years following the change from traditional agriculture or nomadic indigenous lifestyles to more intensive European‐based agriculture. They are deeper erosion channels than rills, but their differentiation is often unclear and arbitrary because of a continuum between the two features. Rills are shallow, ephemeral erosion channels that can be obliterated by standard tillage, alternating cycles of freeze‐thaw, or rain‐impacted shallow overland flows.Attempts to differentiate between gullies and streams on the basis of flow frequency are difficult for two reasons. First, gullies are not restricted to specific climatic regions but have been described in arid, semiarid, subhumid, and humid areas. Second, flow regimes vary systematically based on drainage basin area and climate, and gullying is not restricted to specifically sized basins nor to areas of ephemeral flow.
Heat Balance of Open Waterbodies
Authors: Jöhnk Klaus 
Published: April 2005

AbstractFrom a continuum–mechanical point of view, the heat balance or the thermodynamics of a lake, reservoir, or ocean is governed by three different types of processes: surface fluxes, those through the water surface and the sediment boundary of a water body; internal heat production; and external heat supply. Whereas surface fluxes are accounted for in boundary conditions, supply and production take place in the water volume and are described as additional production terms in the equation of heat (1). Turbulent diffusion and, to a much lesser degree, molecular diffusion lead to a certain temperature stratification, usually dividing a lake into a well‐mixed, upper warm layer, the epilimnion, separated from it by a transition zone a colder hypolimnion. The temperature–depth distribution can be determined from the heat balance equation and boundary conditions describing the surface fluxes into the water. In contrast to this, in a well‐mixed waterbody with a homogeneous temperature distribution, for example, a polymictic lake, all heat production and flux terms are lumped together in a net thermal energy flux. In this case, the heat production terms are treated as fluxes across the surface. Using such a simple system, one can determine the equilibrium temperature of the waterbody for a certain set of meteorologic conditions, that temperature to which the mixed waterbody is driven under the same prevailing meteorologic conditions. For a stratified lake or ocean, such an approach is only of limited use because it does not account for vertical transport of heat in the waterbody. But it can be a good approximation for the surface temperature when the stratification is strong, thus separating the hypolimnion from the well‐mixed epilimnion.
Base Flow
Authors: Jain Sharad K. , Singh Vijay P. 
Published: April 2005

AbstractThis article discusses base flow, an important component of the streamflow hydrograph. The modeling of base flow is described, followed by methods to determine the base flow recession coefficient. The methods to separate base flow are also described.Water may reach a river by flowing over the catchment surface, moving through the soil, or through groundwater. Based on the path taken by water, streamflow may be divided into surface flow, interflow, and base flow. The ASCE defined base flow as the runoff that has reached the stream or river by passing first through the underlying aquifer, rather than by flowing directly on the ground surface. Thus, base flow is that portion of streamflow that is naturally and gradually withdrawn from groundwater storage or other delayed sources. The other names of base flow are groundwater flow, seepage flow, low flow, and fair weather flow.
Microorganisms in Their Natural Environment
Authors: Koschorreck Matthias 
Published: April 2005

AbstractIn their natural aquatic environment, microbes face conditions that principally differ from the picture of a mixture of different microbes swimming around in a kind of liquid culture. The study of microorganisms in laboratory cultures often gives limited information about the role and behavior of microorganisms in their natural habitat. Our understanding of microbes in their natural aquatic habitat was considerably increased by the development ofin situmethods in the last decades. The introduction of microsensors allowed characterizing the microbial habitat on the size scale of microorganisms. The recent advances in microscopic techniques (confocal laser scanning microscopy, atomic force microscopy) offer the possibility of real 3‐D examination of microbial aggregates or biofilms. Molecular techniques such asin situhybridization to study the phylogeny and physiology of microorganisms in their natural environment are rapidly, improving.