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hydrochemistry, etc ; carbon; carbon dioxide; environment; greenhouse gases; lentic systems; lotic systems; primary productivity; solar radiation; surface water; China; Show all 11 Subjects
Abstract:
... Inland waters have been increasingly viewed as hotspots for greenhouse gas (GHG) emissions owing to their strong capability to intercept and mineralize carbon from the terrestrial environment. Although small waterbodies in humid subtropical climates have the potential to emit considerable amounts of GHG, their emission patterns have remained understudied. This study involved intensive measurements ...
hydrochemistry, etc ; air; gels; microplastics; research; salinity; viscosity; water; Show all 8 Subjects
Abstract:
... The pervasiveness of microplastics (MPs) in global oceans is raising concerns about their adverse impacts on ecosystems. The mechanistic understanding of MP transport is critical for evaluating its fate, flux, and ecological risks specifically. Currently, bubble bursting is believed to represent an important route for MP transfer from sea surfaces to the atmosphere. However, the detailed mechanism ...
hydrochemistry, etc ; Flavobacterium; Limnobacter; Pseudomonas; filtration; groundwater; iron; rivers; Show all 8 Subjects
Abstract:
... The redox conditions strongly affect redox kinetics, hydrochemical composition and microbial reactions under river bank filtration (RBF). For investigating the redox conditions, zonation factors, and microbial responses in a typical RBF with high Fe²⁺ and Mn²⁺ contents, three wells were established 20 m apart perpendicular to the south bank of the Songhua River with a constant flow rate of 400 m³/ ...
hydrochemistry, etc ; groundwater; isotopes; rain; surface water; water budget; watersheds; Show all 7 Subjects
Abstract:
... The major factors governing the formation of the chemical and isotopic compositions of surface water in open water bodies (ponds) in the Bodrak River basin have been studied by hydrochemical and isotopic methods. Special attention was paid to studying rainwater, because the chemical and isotopic compositions of atmosphere precipitation, as well as its volume are of great importance in studying the ...
hydrochemistry, etc ; bentonite; clay; erodibility; extrusion; filtration; models; radioactive waste; Show all 8 Subjects
Abstract:
... Compacted bentonite is considered as an engineered barrier in geological disposal of nuclear waste in fractured rocks. One concern with this concept is that the expansion of bentonite into fractures as the system saturates may lead to its erosion by flowing water. The loss of bentonite through erosion over long times may compromise the barrier. Commercial bentonite contains less soluble accessory ...
hydrochemistry, etc ; calcium; fulvic acids; groundwater; polyacrylic acid; sodium; starch; Show all 7 Subjects
Abstract:
... Aggregation behaviors of bare, and sodium polyacrylate (PAA) and starch modified zero-valent-iron nanoparticles (nZVI), as well as their effects on the Cr (VI) removal were investigated by simulating the groundwater. Results showed that increased concentration of PAA (1–6 wt%) and starch (0.1–0.6 wt%) alleviated the aggregation of modified nZVI (abbreviated as P-nZVI and S-nZVI), while there was a ...
hydrochemistry, etc ; bioaccumulation; bioavailability; desorption; environmental exposure; microplastics; risk; sorption; Show all 8 Subjects
Abstract:
... Microplastics (MPs) are being recognized as an emergent route of contaminants to aquatic environments, which initially attracted the research interest on their interactions with organic pollutants. Lately, a turning point of attention is evident, with more published studies reporting the presence of metal(oid)s in plastics. This review assembles the mechanisms occurring on microplastics surfaces t ...
hydrochemistry, etc ; buffering capacity; carbon dioxide; mass transfer; nanobubbles; pH; Show all 6 Subjects
Abstract:
... Carbon dioxide nanobubbles can increase effective gas-transfer to solution and enhance buffering capacity given the stable suspension in water of CO₂ gas within nanobubbles and the existence of larger gas/water interface. The physico-chemical properties and responses of CO₂ nanobubbles were recorded at different generation times (10, 30, 50, and 70 min) and benchmarked against traditional macrobub ...
hydrochemistry, etc ; alluvial aquifer; bedrock; geophysics; groundwater; mineralization; tectonics; Italy; Show all 8 Subjects
Abstract:
... An integrated hydrochemical and geophysical study of the saline paleo-water uprising into the alluvial aquifer of the Oltrepò Pavese plain sector (Po Plain, northern Italy) is presented. This study involved hydrochemical analysis of groundwater, assessment of well logs, and one-, two- and three-dimensional electrical geophysical surveys. The studied area was selected for its characteristic hydroge ...
hydrochemistry, etc ; aquifers; environment; evolution; fluorides; granite; groundwater; models; pH; Show all 9 Subjects
Abstract:
... Crystalline aquifers are layered systems in which the hydrogeological path of waters extends from highly weathered, shallow and porous rocks to poorly weathered, deep and fissured rocks. This varying hydrogeological setting influences the water chemistry in different ways. The paper aims to reconstruct the water-rock interaction process in these various environments starting from a solid reactant ...
hydrochemistry, etc ; Pseudopleuronectes yokohamae; hypoxia; laboratory experimentation; manganese; otoliths; summer; Show all 7 Subjects
Abstract:
... Previous studies have shown an increase in otolith Mn caused by exposure to hypoxic water masses. The mechanism leading to the increases in otolith Mn is still unclear, but might possibly be due to the larger amount of available Mn left in the water column under hypoxia. Thus, this study aimed to examine the relationship between hypoxia, water Mn and otolith Mn through marbled flounder (Pseudopleu ...
hydrochemistry, etc ; adsorption; basins; cadmium; coprecipitation; freshwater; geochemistry; streams; toxicity; Argentina; Show all 10 Subjects
Abstract:
... Cadmium is one of the most toxic metals commonly released due to mining activities. However, its dynamic in contrasting mining environments has not been exhaustively studied. Through mineralogical and hydrochemical analyses, this study identifies Cd mineral sources and its mobility in surficial waters from two different mining environments (i.e. carbonate-rich and carbonate-poor mineral assemblage ...
hydrochemistry, etc ; adsorption; calcium silicate; cement; databases; geochemistry; nickel; solubility; thermodynamics; Show all 9 Subjects
Abstract:
... The objective of the present study is to investigate Ni retention processes in Calcium Silicate Hydrate (CSH) phases, as the main cement hydration products, and to describe them in a generalized form for the first time. In particular, the effects of the CSH Ca/Si ratio (from 0.8 to 1.6) on the equilibrium water chemistry, Ni speciation, adsorption and solubility have been addressed. Nickel adsorpt ...
hydrochemistry, etc ; Actinobacteria; Archaea; genes; genomics; metadata; mineral water; prokaryotic cells; Show all 8 Subjects
Abstract:
... Caucasian Mineral Waters is a unique territory, where various types of mineral waters with overall daily flow over 16 000 m³ are concentrated in a relatively small area. The Yessentukskoye deposit is characterized by high diversity of water types, of which Yessentuki nos. 17 and 4 are produced in the greatest amounts. Biogeochemical activity of microorganisms inhabiting the subsurface hydrosphere ...
hydrochemistry, etc ; biodiversity; fish; pH; rivers; statistical analysis; taxonomy; temperature; watersheds; Show all 9 Subjects
Abstract:
... Abiotic and biotic bounty of riparian waters may be affected by inadequate maintenance works. Improper planning and execution of maintenance works cause changes to hydrological and hydrochemical condition of water in small rivers, affecting biocenose of riverbeds by modifying the taxonomic composition of organisms inhabiting the regulated river section. Five (5) rivers were subject to studies - Pl ...
hydrochemistry, etc ; basins; genetic models; groundwater; heat flow; mountains; quartz; runoff; temperature; Show all 9 Subjects
Abstract:
... The geothermal resources in sedimentary basins have high potential for development and utilization, and have become an important research topic globally. This study focuses on the geothermal system in the northwestern Songliao Basin. Water chemistry and isotopic signatures of geothermal fluids and shallow groundwater are analyzed. Water–rock interactions, recharge sources, and the ages of geotherm ...
hydrochemistry, etc ; curium; environment; feldspar; mica; pH; radioactive waste; sorption; surface roughness; Show all 9 Subjects
Abstract:
... To assess a reliable safety case for future deep underground repositories for highly active nuclear waste the retention of radionuclides by the surrounding host rock must be understood comprehensively. Retention is influenced by several parameters such as mineral heterogeneity and surface roughness, as well as pore water chemistry (e.g., pH). However, the interplay between those parameters is not ...
hydrochemistry, etc ; World Health Organization; ecology; evolution; groundwater; nonpoint source pollution; Algeria; Show all 7 Subjects
Abstract:
... The demonstration of the main phenomena and the predominant chemical reactions in this evolution as well as the qualitative estimation of this water plus the comparison with the norms of the World Health Organization (W.H.O.), indicated that the positive (+) and negative (−) ions have a direct relationship with the geological and hydrogeological characteristics of the region. The maps of variation ...
hydrochemistry, etc ; aquifers; groundwater; humans; politics; pollution; research; salinity; water management; Morocco; Show all 10 Subjects
Abstract:
... The coastal aquifer of the Essaouira syncline (Morocco) was studied to identify the main processes at the origin of the salinization of groundwater. In fact, a multicriteria analysis approach on hydrochemical data and physicochemical parameters of the Plio-Pleistocene aquifer was used to understand their spatio-temporal variation and their origins. Currently, integrated water resource management h ...
hydrochemistry, etc ; Daphnia magna; bioaccumulation; bioavailability; ecotoxicology; nanosilver; stable isotopes; wetlands; zooplankton; Show all 9 Subjects
Abstract:
... Treatment wetlands utilize various physical and biological processes to reduce levels of organic contaminants, metals, bacteria, and suspended solids. Silver nanoparticles (AgNPs) are one type of contaminant that can enter treatment wetlands and impact the overall treatment efficacy. Grazing by filter‐feeding zooplankton, such as Daphnia magna, is critical to treatment wetland functioning; but the ...