Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Complex Wastewater Matrices
Complex wastewater matrices present a major environmental concern. Besides the biodegradable organics, they may contain a great variety of toxic chemicals, heavy metals, and other xenobiotics. The electrochemically activated persulfate process, an efficient way to generate sulfate radicals, has been widely applied to the degradation of such complex effluents with very good results.
  • 903
  • 20 Aug 2021
Topic Review
Terrestrial Evapotranspiration of Three-Gorges Reservoir
Identifying the spatiotemporal variations and influencing climate factors of evapotranspiration (ET) and its components (vegetation transpiration (Ec), soil evaporation (Es), and canopy interception evaporation (Ei)) can greatly improve our understanding of water cycle, carbon cycle, and biogeochemical processes in a warming climate. As the world′s largest hydropower project, the construction of the Three Gorges Project (TGP) coupled with the significant land use/land cover change affected the regional water and energy exchange in the Three Gorges Reservoir Area (TGRA). This study aimed to reveal the spatiotemporal variations and influencing climate factors in ET and its components using PML-V2 products in TGRA during 2000–2020. Results showed that the mean annual ET, Ec, Es, and Ei in TGRA were 585.12, 328.49, 173.07, and 83.56 mm, respectively. The temporal variation of ET was dominated by Ec, with no significant change in the time trend. Es decreased (2.92 mm/y) and Ei increased (1.66 mm/y) significantly mainly in the cultivated land. ET, Ec, and Ei showed a similar seasonal variation pattern with a single peak, while Es presented a bimodal pattern. From the pre-impoundment to the first impoundment period, ET and Ec mainly increased in the head of TGRA, meanwhile, Es in urban area increased significantly by 27.8%. In the subsequent impoundment periods, ET and Ec changed slightly while Es sharply decreased. The Ei increased persistently during different impoundment period. The dominant climate factors affecting changes in Ec and Es were air temperature, vapor pressure deficit, and sunshine hours, while the variation of Ei was mainly affected by air temperature, vapor pressure deficit, and precipitation. 
  • 554
  • 06 Aug 2021
Topic Review
Remediation Solutions for AMDrainage
Acid Mine Drainage (AMD) is a toxic wastewater stream formed when oxygenated water comes into contact with exposed mine rock surfaces containing sulphide minerals. The formation of AMD is most prominent in abandoned mines where water accumulates in mine shafts and pits allowing exposure to sulphide minerals. The resulting AMD is typically characterised by a low pH with high concentrations of heavy metals and dissolved sulphate. When left untreated, AMD streams can cause severe environmental degradation, including the contamination of natural water bodies, destroying aquatic life and toxifying natural habitats. AMD remediation methods can be divided into two main categories, active treatment and passive treatment methods. Active treatment methods are characterised by process inputs such as energy, chemicals, labour and automated control, whereas passive remediation technologies require minimal process inputs and are mostly self-sustaining. Passive treatment methods are typically at source constructions comprising of a combination of naturally occurring geochemical, physical and biological processes.
  • 880
  • 04 Aug 2021
Topic Review
17O in Hydrological Cycle
17O is the one of the naturally occurring stable isotopes of oxygen, and also it has the lowest abundance, 0.038%(). The distribution of isotopes in hydrological systems is controlled by isotope fractionation processes. Oxygen isotopes fractionate through mass-dependent isotopic fractionation, which includes kinetic processes, isotopic exchange reactions, and physicochemical phenomena (diffusion, condensation, and evaporation).
  • 1.6K
  • 03 Aug 2021
Topic Review
Groundwaters’ Pollution and Stygofauna Communities
Pollution is a major threat for freshwater ecosystems; particularly, environmental degradation is depleting water resources, whether because the surface waters contain higher amounts of pollutants, or because pollutants through the soil attain even the underground water reserves. Assessing the effects of pollution is recently considered among the most relevant aims for subterranean biology. However, the impact of pollution on stygofauna varies according to pollutants typology and abundance, and assessing its effects may not be trivial. Even in cases of relatively small concentrations of pollutants in soils and epikarst, their release may be prolonged and determine a chronic groundwater pollution with unexpected detrimental effects. As stygobionts usually have long life cycles, the comprehension of exposure to certain compounds is far from being understood and may have implications on survival, fitness, and fertility rates. Stygofauna is likely intolerant to even a small alteration of such chemical concentrations.
  • 773
  • 13 Jul 2021
Topic Review
Groundwater Remediation Technologies
Groundwater contamination is one of the most concerning issues from uranium mining activities. Radionuclides cannot be destroyed or degraded, unlike some organic contaminants (and similar to metals). Besides, sites, where radionuclides may be found, are mainly radioactive and mixed waste disposal areas, and therefore many other contaminants may also be present in groundwater.
  • 1.1K
  • 05 Jul 2021
Topic Review
Forward Osmosis in Wastewater Treatment
Forward osmosis (FO), driven by the osmotic pressure difference between solutions divided by a semi-permeable membrane, has been recognised as a potential energy-efficient filtration process with a low tendency for fouling and a strong ability to filtrate highly polluted wastewater.
  • 992
  • 02 Jul 2021
Topic Review
Sand Dam Technology
Sand dam technology filters and protects water from contamination and evaporation with low to no maintenance cost. Sand dams improve the socio-economy of the community and help to cope with drought and climate change. However, success depends on the site selection, design, and construction. The ideal site for a sand dam is at a transition between mountains and plains, with no bend, intermediate slope, and impermeable riverbed in a catchment with a slope greater than 2°. The spillway dimensioning considers the flow velocity, sediment properties, and storage target, and the construction is in multi-stages. Recently, the failure of several sand dams because of incorrect siting, evaporation loss, and one-stage construction were reported. Revision of practitioners’ manuals by considering catchment scale hydrological and hydrogeological characteristics, spillway height, and sediment transport are recommended. Research shows that protected wells have better water quality than open wells and scoop holes. Therefore, the community should avoid open defecation, pit latrines, tethering of animals, and applying pesticides near the sand dam. 
  • 1.2K
  • 01 Jul 2021
Topic Review
SGMA and CVSALTS in California
The Sustainable Groundwater Management Act (SGMA) and Central Valley Salinity Alternatives for Long-Term Sustainability (CVSALTS) initiatives have fundamentally changed future groundwater management in California [1,2]. Both embrace a holistic conceptual understanding of the resource and the interconnectedness of this resource with other vulnerable resources and the citizenry of the state. This shift in perspective also creates a need for a new suite of decision support tools to help stakeholders make cost effective, efficient, equitable, transparent and socially responsible decisions in the future.
  • 408
  • 29 Jun 2021
Topic Review
Heat Recovery from Wastewater
Wastewater from domestic, industrial and commercial developments maintains considerable amounts of thermal energy after discharging into the sewer system. 
  • 1.8K
  • 29 Jun 2021
  • Page
  • of
  • 22
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
ScholarVision Creations
Feedback