Which anions are responsible for alkalinity

Incorporating ecosystem functioning into monitoring programs enables a more holistic assessment of river health and a better understanding of restoration effects. Julia Vanessa Kunz, Michael D.

The hyporheic zone, the subsurface region of streams, is a key compartment for in-stream nutrient retention. Knowledge on actual hyporheic processing rates is still limited due to methodological restrictions which are mainly related to the high local and temporal variability of subsurface flow patterns and nutrient transformation processes.

We present a new device which allows quantitative assessment of hyporheic nutrient fluxes and demonstrate its advantages in an exemplary field testing. Fjord and continental shelf environments in the polar regions are host to some of the planet's most productive ecosystems and support economically important fisheries. A key limiting nutrient for many of these marine phytoplankton is nitrogen.

Here we evaluate the potential for a melting Greenland Ice Sheet to supply nitrogen to Arctic coastal ecosystems. We show nitrogen fluxes of a similar order of magnitude to one large Arctic river but yields that are double those typical of Arctic rivers. Heavy storm events may increase the organic matter fluxes from forested watersheds and deteriorate water quality.

Our study in two forested watershed in Korea revealed, that a larger proportion of coniferous forests likely leads to less organic carbon and larger of inorganic nitrogen fluxes to the receiving surface water bodies. More severe monsoon storms in the future will increase the fluxes of dissolved organic matter.

This paper aims to investigate the spatial variability in dissolved organic matter DOM in terms of both concentration and composition in the Congo River network. This study shows that DOM degradation within the Congo Basin results in the transition from aromatic to aliphatic DOM as well as the role of landscape and water residence time on this transition. Spray- and marble-type equilibrators and a membrane-enclosed CO 2 sensor were compared to assess their suitability for continuous p CO 2 measurements in inland waters.

The results suggest that the fast response of the equilibration systems facilitates capturing large spatial variations in p CO 2 during short underway measurements. The membrane-enclosed sensor would be suitable for long-term continuous measurements if biofouling could be overcome by antifouling measures such as copper mesh coverings. A comparison of POC yield was made between karstic rivers and non-karstic rivers to evaluate the influence of carbonate distribution on POC transport.

Considering the cascade reservoir and climate in the Wujiang River, the impacts of reservoirs and extreme drought were estimated in this study. Johanna I. Maize production on steep slopes causes erosion. Where the eroded material ends up is not well understood.

This study assessed transport of sediment in mountainous Vietnam, where maize is cultivated on slopes and rice is cultivated in valleys. Per year, 64 tons per hectare of sediments are brought into the rice fields and 28 tons of those are deposited there. The sediment fraction captured by the paddies is mostly sandy, while fertile silt and clay are exported. Upland erosion thus impacts rice production. Thibault Lambert, Cristian R. Teodoru, Frank C. This manuscript presents a detailed analysis of transport and transformation of dissolved organic matter along the Zambezi River and its largest tributary.

It is the first study to present such a detailed analysis for a whole, large river system, and in particular for a tropical river other than the Amazon. Arthur H. Beusen, Alexander F. Bouwman, Ludovicus P. Intensifying anthropogenic activity over the 20th century including agriculture, water consumption, urbanization, and aquaculture has almost doubled the global nitrogen N and phosphorus P delivery to streams and steadily increased the N : P ratio in freshwater bodies.

Concurrently, the cumulative number of reservoirs has driven a rise in freshwater nutrient retention and removal. Still, river nutrient transport to the ocean has also nearly doubled, potentially stressing coastal environments. In this study, we provide new findings with regards to the spatial distribution of dissolved organic matter DOM concentration, bioavailability, and optical properties during mid-summer hydrologic conditions throughout the Kolyma River basin in northeast Siberia.

This is particularly critical for this region, where the future fate of organic carbon currently frozen in permafrost soils and whether it ultimately is released as CO 2 and CH 4 is tightly linked to the lability of this material.

Oleg S. Pokrovsky, Rinat M. Loiko, Ivan A. Krickov, Sergey G. Kopysov, Larisa G. Kolesnichenko, Sergey N. Vorobyev, and Sergey N. Climate change in western Siberia and permafrost boundary migration will essentially affect the elements controlled by underground water feeding DIC, alkaline earth elements Ca, Sr , oxyanions Mo, Sb, As and U. The thickening of the active layer may increase the export of trivalent and tetravalent hydrolysates in the form of organo-ferric colloids.

The mean riverine DIN export ratio is 0. The DIN export ratio is positively related to agriculture input, and levels of human disturbance and watersheds with high DIN export ratios are likely at advanced stages of N excess.

Michael N. McKnight, Kathleene A. Welch, and William B. In , we discovered extensive permafrost degradation along several km of Crescent Stream. Here we document the responses to water quality, specifically changes to dissolved major ion and suspended sediment characteristics. Lloyd, K. Michaelides, D. Chadwick, J. Dungait, and R. Our interdisciplinary research brings together methodologies from hydrology, soil science and biogeochemistry to address key questions about the transport of cattle slurry in the environment.

The paper provides a novel approach to trace dissolved and particulate components of cattle slurry through an experimental hillslope system. This work provides one of the first examples of using biomarkers to assess the effects of slope gradient and rainfall intensity on the movement of slurry derived-OM.

Rivers transport a large amount of carbon as dissolved organic carbon DOC. Simultaneously, there was a decrease in isotopic composition, indicating that DOC derived from C 4 vegetation is preferentially decomposed. This has implications for the assessment of vegetation in a catchment based on isotope signatures of riverine carbon.

Temnerud, C. Buffam, J. Andersson, L. Nyberg, and K. These solids can be collected, thus removing the scale-forming cations from the water supply. To see this process in more detail, let us consider the reaction for the precipitation of Mg OH 2. Consultation of the solubility guidelines in the experiment reveals that the Ca OH 2 of slaked lime is moderately soluble in water. They are removed by the separate reaction with CO 3 2- ions from the soda ash.

Household water softeners typically use a different process, known as ion exchange. Ion-exchange devices consist of a bed of plastic polymer beads covalently bound to anion groups, such as -COO -. When hard tapwater passes through the ion exchanger left , the calcium ions from the tapwater replace the sodium ions in the ion exchanger. The softened water, containing sodium ions in place of calcium ions, can be collected for household use. Unfortunately, many people with high blood pressure or other health problems must restrict their intake of sodium.

Calcium is one of the principal elements making up the earth's crust. Calcium compounds, when dissolved, make water hard. The presence of calcium in water is a factor contributing to the formation of scale and insoluble soap curds, which are a means of clearly identifying hard water.

A substance that changes the speed or yield of a chemical reaction without being consumed or chemically changed by the chemical reaction. Those filter media which can cause certain reactions to occur in water treatment, such as activated carbon, calcite, manganese greensand, manganese oxides, and dissimilar metal alloys.

An ion with a positive charge. Cation Exchange is an ion exchange process in which cations in solution are exchanged for other cations from an ion exchanger. The removal of alkalinity ions from a solution. A dealkalizer contains strong base anion exchange resin that exchanges chloride the Cl ion of the NaCl for carbonate, bicarbonate and sulfate.

As water passes through the anion resin the carbonate, bicarbonate and sulfate ions are exchanged for chloride ions. The exchange of cation for hydrogen ions by a strong acid cation exchanger operated in the hydrogen form.

The removal of dissolved gasses such as carbon dioxide, methane, hydrogen sulfide, and oxygen by: 1 subjecting the water to a pressure below atmospheric pressure vacuum degassing or 2 passing large amounts of air thoroughly through the water at atmospheric pressure air stripping.

The removal of all ionized minerals and salts both organic and inorganic from a solution by a two-phase ion exchange procedure. First, positively charged ions are removed by a cation exchange resin in exchange for a chemically equivalent amount of hydrogen ions. Second, negatively charged ions are removed by an anion exchange resin for a chemically equivalent amount of hydroxide ions. The hydrogen and hydroxide introduced in this process unite to from water molecules.

This process is also called demineralization by ion exchange. An ion exchange process designed for reduction of silica from a water supply. Typically a strong base anion exchanger operated in the OH- form is used. Tanks that are leased or rented to a facility lacking the means to regenerate the medium, usually ion exchange resin.

A measure of the diameter of particles in a media bed or resin bed. Effective size is that mesh size which will permit 10 percent of the bed's particles to pass and will retain that remaining 90 percent; in other words, that size for which 10 percent of the media grains or particles are smaller and 90 percent are larger.

The water to be treated that is fed in to a given water treatment system. Flow rate is a critical design parameter by which the effectiveness of the water treatment unit is measured. Study Questions Write your answer in a sentence form do not answer using loose words.

The higher the pH, the less hydrogen ions the solution has. What is pH? What is a neutral solution? What is an acidic solution? What is a basic or alkaline solution?

Chemical reactions in the body, the food we eat, medication we take, and the effects of some diseases can add or remove hydrogen or hydroxyl ions in or from our body fluids.