Search results for "Water"
showing 10 items of 9348 documents
Distribution of recent ostracods in inland waters of Sicily (Southern Italy)
2006
From 2003 to 2005, freshwater ostracods were sampled in 67 water bodies of mainland Sicily (Provinces of Agrigento, Caltanisetta, Catania, Enna, Palermo, Messina, Ragusa, Siracusa and Trapani) located from sea level up to 1300 m a.s.l. This survey took into account streams, springs, wells, but especially temporary and ephemeral habitats (e.g., flooded meadows, temporary ponds). The aim of this research was to give the first comprehensive picture of the regional ostracod fauna and establish relationships between the distribution of ostracod species and some habitat features. Altogether, 21 ostracod taxa belonging to five families (Candonidae, Ilyocyprididae, Cyprididae, Notodromadidae, and L…
Studies on the zooplankton of the deep subalpine Lake Garda
1999
The specific composition and seasonal dynamics of the zooplankton of Lake Garda have been studied through monthly surveys in two annual cycles (December 1994-November 1995 and January-December 1997). The assemblage is largely dominated by Copipo-diaptomus steueri, a typical calanoid presently identified in deep (Garda, Iseo) and shallow lakes of NE Italy and in the hinterland of the central Adriatic region (Dalmatia and Marche Region). Cladocerans and the smaller rotifers represent a significant component of the zooplankton from spring to autumn. A re-examination of the results obtained in previous studies does not seem to demonstrate substantial shifts in the composition of the dominant sp…
Experimental test on the use of MS-222 for ostracod anaesthesia: concentration, immersion period and recovery time
2010
Anaesthesia of animals may be useful for different purposes, particularly for veterinary reasons or in experimental research, for manipulation or treatment of immobilized but alive animals. Its use in crustaceans is not uncommon, but it has never been described for Ostracoda. We provide brief and preliminary guidelines on the use of the tricaine mesylate (MS-222) on the widespread freshwater ostracod Eucypris virens and we show that this compound is an effective anaesthetic used as a bath treatment at minimum concentrations of 500 mg L-1. This value is considerably higher than that recommended for other aquatic animals like fish. Recovery time, ranging from 5 to 15 minutes, is mostly determ…
Long-term abundance dynamics of coastal zooplankton in the Gulf of Riga
1998
The dynamics of three most abundant mesozooplankton species in the coastal zone of the Gulf of Riga — Bosmina longispina, Synchaeta baltica, Keratella quadrata — is analyzed to detect the regulating environmental factors. The only significant downward trend of species abundance was found for S. baltica in autumn. Statistically significant correlation was estimated only between the summer salinity and the abundance of B. longispina. K. quadrata though showed a negative correlation with summer salinity. The abundance of S. baltica had only nonsignificant correlations with the environmental factors. The abundance of coastal mesozooplankton species is determined by the combination of hydrologic…
The consequences of the inappropriate use of ventilation systems operating in indoor swimming pool conditions - analysis
2018
Increasingly more leisure facilities, such as water parks or indoor swimming pools are being built in Poland nowadays. In order to ensure the air quality required by standards for such leisure facilities it is necessary to fit them with effectively functioning ventilation. For the removal of excess humidity, as well as chlorine ions occurring as a result of the disinfection of water as well as the carbon dioxide emitted by people using the facility, the ventilation system needs to be appropriately designed and efficient. For this reason, studies into the air quality in such facilities were undertaken. The paper presents the causes and consequences of the inappropriate operation and maintena…
MICROBIAL FUEL CELL WITH Ni-Co CATHODE AND KMnO4 CATHOLYTE
2017
The improving standard of living causes the increases in energy consumption and waste or wastewater production. The possibility of combining wastewater treatment and electricity production can be accomplished by means of a microbial fuel cell. The possibility of wastewater treatment using the Ni-Co alloy as cathode catalyst with KMnO4 catholyte for microbial fuel cells was presented in this paper. The measurements covered the comparison of changes in the concentration of COD, NH4+ and NO3- in the reactor without aeration, with aeration and using a microbial fuel cell (with Ni-Co cathode and KMnO4 catholyte). The reduction time for COD using a microbial fuel cell with the Ni-Co catalyst (and…
Hydro-mechanical behaviour of a sandy silt from a river embankment
2020
The paper presents the results of an experimental campaign aimed at characterizing the hydro-mechanical behaviour of a sandy silt from a river embankment. Due to continuous river level fluctuations and changing climatic and environmental conditions, flood embankment materials experience frequent variations in degree of saturation and suction values. Such variations strongly impact the earthwork performance both in terms of seepage and stability conditions. For these reasons, a detailed characterization of the material behaviour in unsaturated conditions was carried out. Experiments were designed in order to highlight the response of the involved soil in terms of changes in matric suction an…
Assessment of the changes of COD and color in rivers of Latvia during the last twenty years
1998
Analysis of long-term records of the concentrations of water color and chemical oxygen demand for nine river sites in Latvia is reported. The period of observations lasted for the last 20 years. Characteristic features of data include non-normal distributions, serial correlation, seasonality and presence of mostly significant downward trends. In Latvia, the main water quality changes could be explained by the changes of anthropogenic impact and the type of catchment management over the last 20 years.
An Approach to Delineate Groundwater Bodies at Risk: Seawater Intrusion in Liepāja (Latvia)
2018
Groundwater quality in coastal areas is frequently affected by seawater intrusion as a consequence of intensive water consumption. To achieve “good chemical status” of a groundwater body according to Water Framework Directive the effects of saline or other intrusions should not be observed. Groundwater pumping in former decades has caused a significant seawater intrusion into confined aquifer in Liepāja and has led to deterioration of relatively wide coastal area of the third largest city in Latvia. However, the area affected by seawater intrusion is a small part of groundwater body F1 which overall chemical status is good. Thus, no specific management measures have been applied to explore …
QUALITY OF GROUNDWATER AND AQUATIC HUMIC SUBSTANCES FROM MAIN RESERVOIRE OF GROUND WATER No. 333
2015
The conducted research included the estimation of the quality of groundwater from the Main Reservoir of Ground Water No. 333 area in Opole District, Poland. The groundwater in the analyzed region shows high diversity in quality. The main threat for the quality of water in this region is the human household activity. The main pollutants of groundwater are: dissolved phosphorus, nitrate and ammonium. The quality and quantity of dissolved humic substances in groundwater were also investigated. The results showed that the contents of water-extractable organic carbon varied. Presently, the analyzed groundwater is characterized by large differences in dissolved forms of organic carbon. During mig…