COASTAL AND ESTUARINE SEDIMENT DYNAMICS IN THE MEZEN BAY AND ESTUARIES MEZEN AND KULOY

2018 ◽  
Author(s):  
Н. Демиденко ◽  
N. Demidenko
Keyword(s):  
River Water ◽  
River Discharge ◽  
Sea Water ◽  
Sediment Dynamics ◽  
Estuarine Sediment ◽  
Sea Surface ◽  
Cross Sectional ◽  
Sand Waves ◽  
Tidal Estuaries ◽  
High Concentrations

In the Mezen bay and estuaries Mezen and Kuloy can be high concentrations of mud suspension there, involving the formation at times mobile suspensions and settled mud. Within estuaries the river water is mixed with the sea water by the action of tidal motions, by waves on the sea surface and by the river discharge forcing its way to the sea. Nearly all shallow tidal estuaries, where currents exceed about 1,0m s-1 and where sand is present, have sand waves. Sand waves have a variety of cross-sectional and plan forms.

Hair cell changes after cationic stimulation of corti's organ

1989 ◽  
Vol 47 ◽  
pp. 798-799
Author(s):  
Cesar D. Fermin ◽  
Hans-Peter Zenner
Keyword(s):  
Organ Of Corti ◽  
Cross Sectional ◽  
Surface Areas ◽  
High K ◽  
Anatomical Arrangement ◽  
Cell Cytosol ◽  
High Concentrations ◽  
K Concentration ◽  
Cell Changes

Contraction of outer and inner hair cells (OHC&IHC) in the Organ of Corti (OC) of the inner ear is necessary for sound transduction. Getting at HC in vivo preparations is difficult. Thus, isolated HCs have been used to study OHC properties. Even though viability has been shown in isolated (iOHC) preparations by good responses to current and cationic stimulation, the contribution of adjoining cells can not be explained with iOHC preparations. This study was undertaken to examine changes in the OHC after expossure of the OHC to high concentrations of potassium (K) and sodium (Na), by carefully immersing the OC in either artifical endolymph or perilymph. After K and Na exposure, OCs were fixed with 3% glutaraldehyde, post-fixed in osmium, separated into base, middle and apex and embedded in Araldite™. One μm thick sections were prepared for analysis with the light and E.M. Cross sectional areas were measured with Bioquant™ software.Potassium and sodium both cause isolated guinea pig OHC to contract. In vivo high K concentration may cause uncontrolled and sustained contractions that could contribute to Meniere's disease. The behavior of OHC in the vivo setting might be very different from that of iOHC. We show here changes of the cell cytosol and cisterns caused by K and Na to OHC in situs. The table below shows results from cross sectional area measurements of OHC from OC that were exposed to either K or Na. As one would expect, from the anatomical arrangement of the OC, OHC#l that are supported by rigid tissue would probably be displaced (move) less than those OHC located away from the pillar. Surprisingly, cells in the middle turn of the cochlea changed their surface areas more than those at either end of the cochlea. Moreover, changes in surface area do not seem to differ between K and Na treated OCs.

scholarly journals Absolute seasonal temperature estimates from clumped isotopes in bivalve shells suggest warm and variable greenhouse climate

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Niels J. de Winter ◽  
Inigo A. Müller ◽  
Ilja J. Kocken ◽  
Nicolas Thibault ◽  
Clemens V. Ullmann ◽  
...  
Keyword(s):  
Seasonal Variability ◽  
Sea Water ◽  
Isotope Composition ◽  
Sea Surface ◽  
Mean Annual Temperature ◽  
Seasonal Temperature ◽  
Sea Surface Temperatures ◽  
Surface Temperatures ◽  
Temperature Reconstructions ◽  
Bivalve Shells

AbstractSeasonal variability in sea surface temperatures plays a fundamental role in climate dynamics and species distribution. Seasonal bias can also severely compromise the accuracy of mean annual temperature reconstructions. It is therefore essential to better understand seasonal variability in climates of the past. Many reconstructions of climate in deep time neglect this issue and rely on controversial assumptions, such as estimates of sea water oxygen isotope composition. Here we present absolute seasonal temperature reconstructions based on clumped isotope measurements in bivalve shells which, critically, do not rely on these assumptions. We reconstruct highly precise monthly sea surface temperatures at around 50 °N latitude from individual oyster and rudist shells of the Campanian greenhouse period about 78 million years ago, when the seasonal range at 50 °N comprised 15 to 27 °C. In agreement with fully coupled climate model simulations, we find that greenhouse climates outside the tropics were warmer and more seasonal than previously thought. We conclude that seasonal bias and assumptions about seawater composition can distort temperature reconstructions and our understanding of past greenhouse climates.

Can Marine Cloud Brightening Reduce Sea-Surface Temperatures to Moderate Extreme Hurricanes and Typhoons?

2021 ◽  
Vol 6 (3) ◽  
Author(s):  
Salter SH ◽  
Keyword(s):  
Boundary Layer ◽  
Marine Boundary Layer ◽  
Sea Water ◽  
Cloud Condensation Nuclei ◽  
Sea Surface ◽  
Sea Surface Temperatures ◽  
Marine Stratocumulus ◽  
Surface Temperatures ◽  
Stratocumulus Clouds ◽  
Cloud Tops

Elevated sea-surface temperatures are a necessary but not sufficient requirement for the formation of hurricanes and typhoons. This paper suggests a way to exploit this. Twomey [1] showed that cloud reflectivity depends on the size-distribution of cloud drops, with a large number of small drops reflecting more than a smaller number of larger ones. Mid-ocean air is cleaner than over land. Latham [2-4] suggested that reflectivity of marine stratocumulus clouds could be increased by releasing a submicron spray of filtered sea water into the bottom of the marine boundary layer. The salt residues left after evaporation would be mixed by turbulence through the full depth of the marine boundary layer and would be ideal cloud condensation nuclei. Those that reached a height where the air had a super-saturation above 100% by enough to get over the peak of the Köhler curve would produce an increased number of cloud drops and so trigger the Twomey effect. The increase in reflection from cloud tops back out to space would cool sea-surface water. We are not trying to increase cloud cover; we just want to make existing cloud tops whiter. The spray could be produced by wind-driven vessels cruising chosen ocean regions. The engineering design of sea-going hardware is well advanced. This paper suggests a way to calculate spray quantities and the number and cost of spray vessels to achieve a hurricane reduction to a more acceptable intensity. It is intended to show the shape of a possible calculation with credible if not exact assumptions. Anyone with better assumptions should be able to follow the process.

Analysis of water pollution and evaluation of purification measures in an urban river basin

1996 ◽  
Vol 34 (12) ◽  
pp. 33-40 ◽  
Author(s):  
Y. Hosoi ◽  
Y. Kido ◽  
H. Nagira ◽  
H. Yoshida ◽  
Y. Bouda
Keyword(s):  
Water Quality ◽  
River Water ◽  
River Basin ◽  
Urban Areas ◽  
River Flow ◽  
Sea Water ◽  
Water Quality Management ◽  
River Water Quality ◽  
Urban River ◽  
Pollutant Load

The inflow of pollutant load from urban areas and the stagnation of water due to sea water intrusion cause the deterioration of river water quality in tidal zone. In order to improve water quality, various measures such as the reduction of pollutant load by sewage systems, discharge control from sewage treatment plants considering river flow, nutrient removal by aquatic plants, and the dredging of bottom sediments have been examined. The choice of these measures depends on the situation of the river environment and finances. In this study, a field survey was carried out in a typical urban river basin, first. Secondly, on the basis of this survey, a mathematical model was formed to simulate flow and water quality. Several purification alternatives designed for the investigated river basin were comparatively evaluated from the viewpoint of the effect of water quality improvement and their cost. Finally, they were prioritized. Through this case study, a planning process of river water quality management was shown.

scholarly journals Hydrochemical Evolution in Ciliwung River – Java, Indonesia: Study of Sea Water Mixture and Mineral Dissolution

2020 ◽  
Vol 20 (6) ◽  
pp. 1360
Author(s):  
Evarista Ristin Pujiindiyati ◽  
Paston Sidauruk ◽  
Tantowi Eko Prayogi ◽  
Faizal Abdillah
Keyword(s):  
River Water ◽  
Rainy Season ◽  
Sea Water ◽  
Dry Season ◽  
Mineral Dissolution ◽  
Water Type ◽  
Water Mixture ◽  
Hydrochemical Evolution ◽  
Increasing Trend ◽  
Saturation Indexes

The chemical characteristics of the Ciliwung River were analyzed to understand hydrochemical evolution. A fraction of sea water mixture and kinds of mineral controlling for chemicals were also determined. During three year investigations in 2015, 2016, and 2018, electrical conductivity increased with decreasing elevations. Two hydrochemical facies had been identified for the Ciliwung river water; those were Ca-Mg-HCO3 and Ca-Na-HCO3.  The river water mixing with seawater was recognized in the Mangga Dua site in which its water type had shifted to Na-Ca-HCO3-Cl. Based on Na-Cl contents, the fraction of sea water into the Ciliwung River reached 2% in the Mangga Dua site during the dry season and decreased to 0.7% during the rainy season in 2015. The much higher monthly rainfall during the dry season in 2016 and 2018 had washed out invading seawater from the Mangga Dua site; its fraction of sea water was less than 0.4%. Saturation indexes with respect to calcite, dolomite, and gypsum minerals showed an increasing trend related to the decreasing elevations. All water samples were undersaturated with respect to gypsum. Meanwhile, saturation indexes with respect to calcite and dolomite mostly indicated undersaturated, except in the Mangga Dua site that was saturated (during the rainy season in 2015 and dry season in 2018) and supersaturated during the dry season in 2015.

scholarly journals Fluxes and retention of nutrients and organic carbon in Manko estuary, Okinawa, Japan: influence of river discharge variations

2014 ◽  
Vol 5 (2) ◽  
pp. 141 ◽  
Author(s):  
D. Shilla
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
River Water ◽  
Rainy Season ◽  
River Discharge ◽  
Geochemical Processes ◽  
Dissolved Nutrients ◽  
Transport And Transformation ◽  
Organic Nutrients ◽  
Annual Transport

Estuaries are often considered important filters for inorganic and organic nutrients, as they are located between the land and sea. This study reports on the fluvial fluxes and estuarine transformations and retention of dissolved nutrients (total oxidized nitrogen [TON = NO<sub>2</sub><sup>−</sup> and NO<sub>3</sub><sup>−</sup>]), NH<sub>4</sub><sup>+</sup>, PO<sub>4</sub><sup>3−</sup>, and dissolved organic carbon (DOC) in Manko estuary, Okinawa, Japan. The transport and transformation of dissolved nutrients and DOC varied widely among the eight conducted surveys due to variations in freshwater discharge and subsequent flushing times. Under high fluvial discharge, particularly during the May–June rainy season, the transport of nutrients and DOC accounted for up to 70%, 88%, 93%, and 53% of the annual transport of TON, NH<sub>4</sub><sup>+</sup>, PO<sub>4</sub><sup>3−</sup>, and DOC, respectively. The flushing times of river water into the estuary, which varied from 0.5 to 46 days, were important in determining the degree to which fluvial nutrients were transformed and retained within the estuary. The effect of long flushing times was evident during the dry months (December–March), when biological and geochemical processes within the estuary removed most of the fluvial nutrients and DOC.

A miscellaneous catalogue of mean, vuglar, cheap and simple experiments. Drawn up by Sr. William Petty, President of the Dublin Society, and by him presented to that Society

1685 ◽  
Vol 15 (167) ◽  
pp. 849-853
Keyword(s):  
River Water ◽  
Sea Water ◽  
Spring Water ◽  
Rain Water ◽  
Rape Oil ◽  
Water Spring

I. The Weight of a Cubical foot of Sea-Water, fresh River-Water, Spring-Water and Rain-Water ; as also of Ale, French Wine, Brandy, Metheglin and Spanish Wine, Oil-Olive, Rape-Oil and Train-Oil?

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