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A recent study has shown increased warming in the fjords of west Spitsbergen. Their location is critical, as they are situated along the main northward pathway of Atlantic Water (AW) which is a great source of heat to the Arctic Ocean and the fjords. In the light of ongoing warming, we aim to discuss differences between the fjords under northward transformation of oceanic waters. We compared summer hydrographic conditions in two fjords located in two opposite ends of west Spistbergen: Hornsund in the south and Kongsfjorden in the north. The study is based on high resolution CTD measurements collected during Arctic cruises between 2001 and 2015. The emphasis was put not only on differences in water temperature, salinity and water masses but also the freshwater content (FWC), AW transport and heat delivery to the fjords. In general, the water in Kongsfjorden is on average 18C warmer and its salinity is higher by 0.5 compared to Hornsund. It is also characterized by two times greater transport of AW and heat delivery to the fjord. On the other hand, Hornsund reveals two times higher FWC. Both fjords undergo a gradual warming due to an increased presence of Atlantic origin waters. The ongoing warming is accompanied by an increase in variability of temperature and salinity dependent on the domination of the Sørkapp Current (SC) or the West Spitsbergen Current (WSC) on the West Spitsbergen Shelf (WSS). Nonetheless, Hornsund remains more Arctic-type fjord compared to Kongsfjorden, due to stronger blocking by SC.
Zooplankton was investigated at fixed site in 24 hours in Kongsfjorden, a glacial fjord situated on the west coast of Spitsbergen (Svalbard) (79°N, 12°E), in order to unveil the level of diurnal variability in community composition and abundance. Parallel to zooplankton study water temperature and salinity were measured while information on local tides and winds was obtained from external sources. Observed changes did not exceed the range of variability regarded intrinsic, resulting from the nature of plankton. Because of this low variability we are of the opinion that the data presented can be regarded a valid measure of the natural heterogeneity of zooplankton communities in hydrologically dynamic Arctic coastal waters in summer. The observed changes in zooplankton were primarily induced by the complex dynamics of the fjord's water masses. In spite of importance of tidal forcing, the variability in zooplankton did not demonstrate similar temporal fluctuations due to modification of the water movement by other irregular forces (local wind). Also, we have not found any indication of diel vertical migration in coastal water in the Arctic under the condition of midnight sun.
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Between May and October of 2003, mineral composition of surface (0.5 m deep) and bottom (5.0 meters) waters, at measurement stations in north-western and south-eastern parts of Great Lagoon (Szczecin Lagoon), have been studied. Total concentrations of ionic macrocomponents: Na+, K+, Ca2+, Mg2+, Cl-, HCO3 - , SO4 2- have been determined. Differentiation of ionic composition and changing level of concentrations of ionic macrocomponents in waters, depending on location of measurement station, depth of water sample collection and time of examination, have been proved. Bottom waters in south-eastern part of Great Lagoon had highest salinity level, whereas surface waters in the same location had lowest degree of salinity. Taking into consideration relatively small number of measurements, authors of present paper regard outlined investigations as diagnostic and obtained conclusions as preliminary ones. Towards substantial variability in ionic composition and magnitudes of concentrations, it is practically impossible to forecast and define values of concentrations of individual ionic components and general salinity degrees, basing on chlorides concentrations, what was often pursued, until now.
This research was conducted to evaluate the effects of water salinity and nano-silica (NS) and humic acid (HA) on Bermuda grass. The study was carried out under greenhouse and exterior space conditions in a completely randomized design with factorial arrangements. Treatments included 4 water salinity levels (0, 5, 7 and 9 dS/m) and 4 level of NS (0, 1, 2 and 3 mm/l) as well as 4 level of HA (0, 50, 100 and 150 mg/l). Results indicated a decrease in chlorophyll content, and increase in proline, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD) and electrolyte leakage (EL) with increasing levels of salinity. The chlorophyll content in greenhouse and exterior space also increased with increasing levels of NS and HA, while proline in two environments, with increasing levels of NS and HA decreased. EL with increasing levels of NS fluctuated, but with increasing levels of HA, it decreased in two environments. With increasing levels of NS, CAT in both environments was eventually decreased after the oscillation, but there was no particular trend in HA levels. With increasing levels of NS and HA, MDA in the greenhouse decreased and in the exterior space – it increased. Finally, by increasing levels of NS and HA, SOD did not show any change in the greenhouse condition, but in the exterior space, the SOD was decreased.
The present studies were concentration of ammonia, nitrite, nitrate, dissolved oxygen, temperature, salinity and pH. For seven physicochemical parameters were determined in marine water samples along with marine ornamental fish water sources from CAS in marine biology laboratory conditions at Parangipettai. Water sample have been studied at a marine water sources. The study concentrations of parameters like ammonia, nitrite, nitrate, dissolved oxygen, temperature, salinity, and pH. And physicochemical parameters have been calculated. The data showed the difference of the investigated parameters in samples as follows; Concentration of water quality parameters like ammonia was maximum level above 1.158 μmol¯1, nitrite was ranging from 0.811 to 0.922 μmol¯1, nitrate was range maximum level above 4.84 μmol¯1, dissolved oxygen content was maximum level above 2.4 mg¯1, temperature was ranging from 32.3 to 100 °C, salinity values ranging from 0 to 36ppt and pH was ranging from 6.5 to 8.0. During the study period of from July 2013 to June 2014 we investigated concentration of seven physicochemical parameters value Marine water samples with cultured fish species in presence of water from CAS in Marine Biology laboratory Annamalai University at Parangipettai.
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