Search results for "Aquatic Science"
showing 6 items of 2026 documents
Numerical Simulations of the Flow Field of a Submerged Hydraulic Jump over Triangular Macroroughnesses
2021
The submerged hydraulic jump is a sudden change from the supercritical to subcritical flow, specified by strong turbulence, air entrainment and energy loss. Despite recent studies, hydraulic jump characteristics in smooth and rough beds, the turbulence, the mean velocity and the flow patterns in the cavity region of a submerged hydraulic jump in the rough beds, especially in the case of triangular macroroughnesses, are not completely understood. The objective of this paper was to numerically investigate via the FLOW-3D model the effects of triangular macroroughnesses on the characteristics of submerged jump, including the longitudinal profile of streamlines, flow patterns in the cavity regi…
Lipid-related thiamine deficiency cause mortality of river lampreys (Lampetra fluviatilis) during pre-spawning fasting
2023
Publisher Copyright: © 2023 The Authors River lampreys (Lampetra fluviatilis) were caught in the fall 2014 on entering the River Perhonjoki for spawning and kept at a hatchery until spawning in late spring 2015 to produce larvae for compensatory stockings. Since the lampreys died massively from early February onwards, they were investigated in March and May to clarify the cause of the deaths. The symptoms in lampreys resembled those of lipid-related thiamine (vitamin B1) deficiency of salmonines, called the M74 syndrome in the Baltic Sea area. Because the lipid content of lampreys was known to be high, thiamine concentrations were analyzed in the liver and ovulated unfertilized eggs, and th…
Biopolymer Recovery from Aerobic Granular Sludge and Conventional Flocculent Sludge in Treating Industrial Wastewater: Preliminary Analysis of Differ…
2022
The recovery of biopolymers from sewage sludge could be a crucial step in implementing circular economy principles in wastewater treatment plants (WWTP). In this frame, the present study was aimed at evaluating the simultaneous production of polyhydroxyalkanoates (PHA) and extracellular polymeric substances (EPS) obtainable from the treatment of agro-industrial wastewater. Two biological enrichment systems, aerobic granular sludge (AGS) and a conventional activated sludge operating as a sequencing batch reactor (SBR), were monitored for 204 and 186 days, respectively. The maximum biopolymers accumulation capacity was close to 0.60 mgPHA-EPS gVSS−1 in the AGS when operating at 3 kgCODm…
Levels and Potential Health Hazards of Chlorinated Pesticidesin Surface Water Samples of Charsadda Area of Pakistan Using SPME-GC-ECD Technique
2021
In the present study, we determined the levels of chlorinated pesticide residues in surface water samples collected from the Charsadda district (KPK, Pakistan). SPME-GC-ECD with COMBI PAL CTC autosampler was used for extraction and analysis of 20 organochlorine pesticides in the collected water samples. For maximum efficiency of the SPME procedure, several parameters were studied, including the extraction and desorption time of the fiber, solution pH, agitation of samples, and stirring speed, etc. This method showed good liner response, with R2 values in the range of 0.9887 to 0.9999 for all pesticides. This method also provided good percent recoveries at 1 µg L−1 (87.5 to 106.0%) and at 2 …
Oxidative stress biomarkers in the copepod Limnocalanus macrurus from the northern Baltic Sea : effects of hydrographic factors and chemical contamin…
2015
Relationship between trophic state and plankton community structure in 21 Sicilian dam reservoirs
1994
The relationship between the trophic state of 21 Sicilian dam reservoirs and their taxonomic community structure of phytoplankton (87 taxa) as well as zooplankton (45 taxa) have been examined by means of cluster analysis performed using annual average biomass values. The phytoplankton community structure was closely connected with the trophic state of the reservoirs, whereas the zooplankton community structure was related to hydrological regimes peculiar to the individual water bodies and not to the trophic state. © 1994 Kluwer Academic Publishers.