scholarly journals The role of ocean cooling in setting glacial southern source bottom water salinity

2012 ◽  
Vol 27 (3) ◽  
pp. n/a-n/a ◽  
Author(s):  
M. D. Miller ◽  
J. F. Adkins ◽  
D. Menemenlis ◽  
M. P. Schodlok
Keyword(s):  
Bottom Water ◽  
Water Salinity

scholarly journals The role of turbulent mixing in the modified Shelf Water overflows that produce Cape Darnley Bottom Water

2015 ◽  
Vol 120 (2) ◽  
pp. 910-922 ◽  
Author(s):  
Daisuke Hirano ◽  
Yujiro Kitade ◽  
Kay I. Ohshima ◽  
Yasushi Fukamachi
Keyword(s):  
Turbulent Mixing ◽  
Bottom Water ◽  
Shelf Water

scholarly journals Mollusks as Indicators of the State of Soil and Water in Uzbekistan

2021 ◽  
Vol 7 (4) ◽  
Author(s):  
Z. Izzatulaev ◽  
Kh. Boimurodov
Keyword(s):  
Narrow Range ◽  
Water Salinity ◽  
Mountain Forest ◽  
Meadow Steppe ◽  
Vital Activity ◽  
Hydromorphic Soil ◽  
Wide Range ◽  
Soil And Water ◽  
Terrestrial Mollusks

The work examines the vital activity of mollusks. About 160 species of terrestrial mollusks have been identified in Uzbekistan. It has been established that 12 species of terrestrial mollusks live on the plains in the steppe serozem soils at heights. Psychromezobionts live in hydromorphic soil among turf and under stones. Typical and dark soils are home to over 20 species of mollusks. On brown, brown-mountain-forest, light-brown meadow-steppe soils, 4 species of endemic mollusks live. Brackish-water mollusks were also found, which are divided into eurygane, living in a wide range of water salinity, and stenohaline, living in a narrow range of water salinity. Mollusks-indicators of the type and condition of the soil have been determined. In conclusion, the author concludes that it is necessary to further study the species composition and indicator role of mollusks in Uzbekistan.

scholarly journals Large variations in iron input to an oligotrophic Baltic Sea estuary: impact on sedimentary phosphorus burial

2018 ◽  
Vol 15 (22) ◽  
pp. 6979-6996 ◽  
Author(s):  
Wytze K. Lenstra ◽  
Matthias Egger ◽  
Niels A. G. M. van Helmond ◽  
Emma Kritzberg ◽  
Daniel J. Conley ◽  
...  
Keyword(s):  
Organic Matter ◽  
Baltic Sea ◽  
Reactive Transport ◽  
Bottom Water ◽  
Transport Model ◽  
Coastal Sediments ◽  
Estuarine Sediments ◽  
Water Salinity ◽  
The Baltic Sea ◽  
The Baltic

Abstract. Estuarine sediments are key sites for removal of phosphorus (P) from rivers and the open sea. Vivianite, an Fe(II)-P mineral, can act as a major sink for P in Fe-rich coastal sediments. In this study, we investigate the burial of P in the Öre Estuary in the northern Baltic Sea. We find much higher rates of P burial at our five study sites (up to ∼0.145 molm-2yr-1) when compared to more southern coastal areas in the Baltic Sea with similar rates of sedimentation. Detailed study of the sediment P forms at our site with the highest rate of sedimentation reveals a major role for P associated with Fe and the presence of vivianite crystals below the sulfate methane transition zone. By applying a reactive transport model to sediment and porewater profiles for this site, we show that vivianite may account for up to ∼40 % of total P burial. With the model, we demonstrate that vivianite formation is promoted in sediments with a low bottom water salinity and high rates of sedimentation and Fe oxide input. While high rates of organic matter input are also required, there is an optimum rate above which vivianite formation declines. Distinct enrichments in sediment Fe and sulfur at depth in the sediment are attributed to short periods of enhanced input of riverine Fe and organic matter. These periods of enhanced input are linked to variations in rainfall on land and follow dry periods. Most of the P associated with the Fe in the sediment is likely imported from the adjacent eutrophic Baltic Proper. Our work demonstrates that variations in land-to-sea transfer of Fe may act as a key control on burial of P in coastal sediments. Ongoing climate change is expected to lead to a decrease in bottom water salinity and contribute to continued high inputs of Fe oxides from land, further promoting P burial as vivianite in the coastal zone of the northern Baltic Sea. This may enhance the role of this oligotrophic area as a sink for P imported from eutrophic parts of the Baltic Sea.

scholarly journals Reconstruction of Pacific Ocean bottom water salinity during the Last Glacial Maximum

2014 ◽  
Vol 41 (8) ◽  
pp. 2914-2920 ◽  
Author(s):  
Tania Lado Insua ◽  
Arthur J. Spivack ◽  
Dennis Graham ◽  
Steven D'Hondt ◽  
Kathryn Moran
Keyword(s):  
Pacific Ocean ◽  
Last Glacial Maximum ◽  
Bottom Water ◽  
Glacial Maximum ◽  
Water Salinity ◽  
Ocean Bottom ◽  
Last Glacial ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Exploring the Role of Ecological Groin in Improving River Water Quality: A Case Study in Wangyu River, China

2013 ◽  
Vol 361-363 ◽  
pp. 589-594
Author(s):  
Cong Cong Chen
Keyword(s):  
Water Quality ◽  
River Water ◽  
Bottom Water ◽  
Stream Water ◽  
Suspended Solid ◽  
River Water Quality ◽  
Particulate Phosphorus ◽  
Stream Water Quality ◽  
Surface Intermediate

The ecological groin being built using elastic filter bulb with biologic filler, has received attention in the community for its role in improving stream water quality through altering stream hydrodynamics, intercepting sediment and thereby reducing the sediment-attached nutrients. As an important watercourse for the project Transferring Yangtse River into Taihu Lake, Wangyu River, was chosen in this study to investigate the effect of ecological groin based on two sampling campaigns in April 2012. The results showed that suspended solid (SS) and total phosphorus (TP) concentration in the water decreased significantly after the ecological groin. The SS and TP concentration in the surface, intermediate and bottom water decreased after the ecological groin by 53.5% and 12.7%, 44.0 %and 14.5%, and 35.5% and 9.3%, respectively, which were greatly related to the facts that ecological groin favored sedimentation and that the total particulate phosphorus accounted for up to 75.0% of TP in the water. Comparatively, TN concentration in the surface, intermediate and bottom water decreased after the ecological groin by 5.6%, 2.4% and 5.1%, respectively. The findings of this study enable us to gain insight into the role of ecological groin in improving river water quality.

Role of the Drake Passage in Controlling the Stability of the Ocean’s Thermohaline Circulation

2005 ◽  
Vol 18 (12) ◽  
pp. 1957-1966 ◽  
Author(s):  
Willem P. Sijp ◽  
Matthew H. England
Keyword(s):  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Deep Water ◽  
Bottom Water ◽  
Multiple Equilibria ◽  
Thermohaline Circulation ◽  
Drake Passage ◽  
Global Ocean ◽  
Intermediate Water

Abstract The role of a Southern Ocean gateway in permitting multiple equilibria of the global ocean thermohaline circulation is examined. In particular, necessary conditions for the existence of multiple equilibria are studied with a coupled climate model, wherein stable solutions are obtained for a range of bathymetries with varying Drake Passage (DP) depths. No transitions to a Northern Hemisphere (NH) overturning state are found when the Drake Passage sill is shallower than a critical depth (1100 m in the model described herein). This preference for Southern Hemisphere sinking is a result of the particularly cold conditions of the Antarctic Bottom Water (AABW) formation regions compared to the NH deep-water formation zones. In a shallow or closed DP configuration, this forces an exclusive production of deep/bottom water in the Southern Hemisphere. Increasing the depth of the Drake Passage sill causes a gradual vertical decoupling in Atlantic circulation, removing the influence of AABW from the upper 2000 m of the Atlantic Ocean. When the DP is sufficiently deep, this shifts the interaction between a North Atlantic Deep Water (NADW) cell and an AABW cell to an interaction between an (shallower) Antarctic Intermediate Water cell and an NADW cell. This latter situation allows transitions to a Northern Hemisphere overturning state.

scholarly journals Invertebrate hydrobiont fauna transformation in the Dombrovskyi pit lake during the period of 2014-2018

2021 ◽  
pp. 94-104
Author(s):  
T. Mykitchak ◽  
◽  
V. Kozlovskyy ◽  
O. Mateleshko ◽  
◽  
...  
Keyword(s):  
Species Diversity ◽  
Brachionus Plicatilis ◽  
Water Layer ◽  
Aquatic Invertebrate ◽  
Water Salinity ◽  
Pit Lake ◽  
Invertebrate Community ◽  
First Time ◽  
Cloeon Dipterum

The aquatic invertebrate community of Dombrovskyi pit lake was investigated during 2014–2018. 25 species were recorded there. The only permanent component of plankton in the community is rotifer Brachionus plicatilis Müller, 1786; of benthos and neuston is hemipteran Sigara lateralis (Leach, 1817), beetle Hydrobius fuscipes (Linnaeus, 1758), flies Aedes sp., Ochlerotatus lepidonotus (Edwards, 1920), Culicoides salinarius Kieffer, 1914, Ephydra glauca Meigen, 1830 are permanent components of benthos and neuston. The main diversity of invertebrates is concentrated in littoral zone up to 2 m of depth. This is primarily due to the desalination of these areas by surface runoff. Over the last decade the mineralization of the surface water layer has decreased from 120–138 to 25–28 g/l. Combined with the desalination of water, the increase of species diversity of aquatic invertebrates was noticed in spring seasons (from 7 to 17 taxa). The freshwater taxa, which are not tolerant even to low water salinity, appeared in the community in 2018 (7–25 % of the species diversity), among them Hydrometra stagnorum (Linnaeus, 1758), Rhyacophila tristis Pictet, 1834, Coelambus impressopunctatus (Schaller, 1783), Enochrus coarctatus (Gredler, 1863), Hydrophilus caraboides (Linnaeus, 1758). The role of freshwater taxa, which are tolerant to low water salinity (up to 5 g/l), increased from 0–10 % of the species diversity in 2014–2015 to 22–35 % in 2018. Among them Eucyclops serrulatus (Fischer, 1851), Candona sp., Cypris pubera O. F. Müller, 1776, Cloeon dipterum (Linnaeus, 1760), Libellula depressa Linnaeus, 1758, Sympecta fusca Vander Linden, 1820, Paracorixa concinna (Fieber, 1848) was noted in 2018 for the first time. On the contrary, the number of saltwater taxa decreased from 20–29 % (2014–2015) to 5–14 % (2018). The saltwater aquatic invertebrate community of this pit lake has transformed into brakish-freshwater one over time. 83 % taxa of aquatic invertebrate communities from freshwater puddles near reservoir coast are noted in the Dombrovska reservoir. The introduction of species from protective canals of the reservoir is unlikely, as only 5 % of taxa from there are marked in it. The main way of the forming communities of invertebrates in this reservoir is the periodical flooding of freshwater coastal puddles.

scholarly journals Striking Dependence of Protein Sweetness on Water Quality: The Role of the Ionic Strength

2021 ◽  
Vol 8 ◽  
Author(s):  
Masoud Delfi ◽  
Alessandro Emendato ◽  
Piero Andrea Temussi ◽  
Delia Picone
Keyword(s):  
Water Quality ◽  
Ionic Strength ◽  
Mechanism Of Action ◽  
Experimental Validation ◽  
Food Additives ◽  
Water Salinity ◽  
Sweet Proteins

Sweet proteins are the sweetest natural molecules. This aspect prompted several proposals for their use as food additives, mainly because the amounts to be added to food would be very small and safe for people suffering from sucrose-linked diseases. During studies of sweet proteins as food additives we found that their sweetness is affected by water salinity, while there is no influence on protein’s structure. Parallel tasting of small size sweeteners revealed no influence of the water quality. This result is explained by the interference of ionic strength with the mechanism of action of sweet proteins and provides an experimental validation of the wedge model for the interaction of proteins with the sweet receptor.

Sign in / Sign up

Export Citation Format

Share Document