scholarly journals CHANGE OF HEAT FLUX AT THE WATER-BOTTOM SEDIMENTS BOUNDARY IN A SMALL LAKE DURING THE YEAR

2021 ◽  
Vol 6(16) (4) ◽  
pp. 116-128
Author(s):  
G. E. Zdorovennova ◽  
G. G. Gavrilenko ◽  
N. I. Palshin ◽  
T. V. Efremova ◽  
S. R. Bogdanov ◽  
...  
Keyword(s):  
Heat Flux ◽  
Water Column ◽  
Bottom Sediments ◽  
Ice Formation ◽  
Heat Accumulation ◽  
Daily Frequency ◽  
Southern Karelia ◽  
Ice Period ◽  
Polymictic Lake ◽  
Water Bottom

The features of the variability of the heat flux at the boundary of the water column with bottom sediments in the central part of the small polymictic Lake Vendyurskoe (southern Karelia) were analyzed according to the data of year-round temperature measurements from November 2018 to October 2019. It was shown that the heat flux directed from the bottom sediments into the water reached 6–8 W/m2 in the pre-ice period and at the moments of ice formation and breaking, and did not exceed 1 W/m2 during most of the winter. A week after the ice-off (May 3–4, 2019) the water column was completely mixed, the heat flux changed its sign, and heat accumulation in the upper layer of bottom sediments began. The heat flux directed to bottom sediments was 4–6 W/m2, periodically increasing to 8-12 W/m2 from mid-May to late July and from the second decade of August to the first decade of September. Against the background of a prolonged cooling during the first ten days of August, the heat flux changed sign with daily frequency, the amplitude of daily fluctuations reached ± 2.5 W/m2. Autumn cooling of the Lake Vendyurskoe began in early September 2019, the heat flux sign changed on September 14–16, 2019.

scholarly journals Seasonal change in heat flux at the water-bottom sediment boundary in a small lake

2021 ◽  
Vol 2131 (3) ◽  
pp. 032080
Author(s):  
G Zdorovennova ◽  
A Terzhevik ◽  
N Palshin ◽  
T Efremova ◽  
S Bogdanov ◽  
...  
Keyword(s):  
Heat Flux ◽  
Heat Exchange ◽  
Bottom Sediments ◽  
Temperature Fluctuations ◽  
Temperate Zone ◽  
Bottom Boundary ◽  
Small Lake ◽  
Wide Range ◽  
Ice Period ◽  
Water Bottom

Abstract Heat exchange with bottom sediments is the main component of the thermal regime of ice-covered shallow lakes of the temperate zone, which explains the importance of its study and parameterization for inclusion in numerical models. Circulations arising in ice-covered lakes due to heat exchange with bottom sediments, and existing for several months, can make a significant contribution to the transport of dissolved and suspended particles along the water column. The aim of this work was to study the seasonal variability of the heat flux at the waterbottom boundary in a shallow lake during the under-ice period, including the period of spring under-ice convection. Based on the analysis of data from high-frequency (minute) long-term measurements of water temperature in the bottom area of a small lake in the temperate zone, a wide range of variability of the heat flux across the water-bottom boundary during the winter from minute to daily fluctuations was established. The role of the spring under-ice heating in the change in the heat flow at the water-bottom boundary is shown. It is shown that shallow areas of the lake bottom, falling into the zone of influence of spring subglacial convection, can accumulate heat already at the end of the ice period. The comparison of temperature fluctuations in the deep-water part of the lake and tin he area with depths close to the average is carried out. It is shown that the spectrum of temperature fluctuations has similar periods, however, in time, sharp temperature jumps in different areas of the lake do not coincide.

ANALYSIS OF ACCUMULATION AND DISTRIBUTION OF LEAD IN THE SYSTEM WATER-BOTTOM SEDIMENTS IN THE BACH DANG ESTUARY (VIETNAM)

2017 ◽  
pp. 62-66
Author(s):  
Truong Van Tuan ◽  
Irina Vladimirovna Volkova
Keyword(s):  
Bottom Sediment ◽  
Bottom Sediments ◽  
Water Samples ◽  
Suspended Solids ◽  
Natural Habitat ◽  
Bottom Layer ◽  
Sediment Samples ◽  
Natural Breeding ◽  
System Water ◽  
Water Bottom

Research was held in the estuary of the river Bach Dang (Dongbay community, Rakhtay district, Hai Phong, Vietnam) in June, 2012 - May, 2013. Concentration of lead was studied in water, suspended solids and bottom sediment. Clam beach (natural breeding environment of Meretrix lyrata ) was inspected regularly, every month. Water samples were taken 6 times from the bottom layer 10 cm down the bottom, once per 3 hours in each of 12 investigated zones. Bottom sediment samples were taken at the depth 2 cm. The findings show that lead accumulates mainly in suspended solids (23.3 mg/kg) and in bottom sediment (14.31 mg/kg), in water it is in small quantities (0.003 mg/kg). Analysis of bottom sediment samples taken in different places showed that they have even leadcontent, lead is distributed uniformly, localization of contaminations is not found. The results obtained can be assumed as the basis for investigating lead accumulation and its excretion by clam Meretrix lyrata organisms in the natural habitat.

INFLUENCE OF THE ECOLOGICAL STATE OF THE SEREPOK RIVER (VIETNAM) ON ACCUMULATION OF HEAVY METALS IN ORGANS OF FISH

2017 ◽  
pp. 98-105
Author(s):  
Ngo The Cuong ◽  
Tran Hoan Quoc ◽  
Svetlana Vasilievna Zolotokopova
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
River Water ◽  
Bottom Sediments ◽  
Heavy Metal Concentration ◽  
Industrial Areas ◽  
Industrial Regions ◽  
Cadmium Lead ◽  
Sarotherodon Galilaeus ◽  
Water Bottom

The article focuses on the study of change of containing heavy metals (zinc, copper, iron, cadmium, lead, arsenic) in the abiotic and biotic components of the Serepok river (Vietman) influenced by wastewater discharge from industrial areas. Heavy metal content was determined in the river water and bottom sediments in the four zones: above and within the boundaries of industrial regions Xoa Phu and Tam Thang and in two water reservoirs situated below the boundaries of those industrial areas. Tilapia Galilean ( Sarotherodon galilaeus ), Hemibagrus ( Hemibagrus ), and sazan ( Cyprinus carpio ) caught in these areas were the hydrobionts under study in which liver, gills, skeleton and muscles accumulation of heavy metals was detected. In the organs of fish caught in the river within industrial region, heavy metals concentration was 3-7 times higher. The greatest concentration of heavy metals was found in the liver and gills of fish caught in the boundaries of industrial regions, the least concentration was in the muscles. In most cases, significant correlation between heavy metal concentration in organs of fishes and in river water, bottom sediments has been revealed.

Sedimentation of Pb-210 in Laurentian Shield Lakes

1984 ◽  
Vol 19 (2) ◽  
pp. 97-109 ◽  
Author(s):  
R.J. Cornett ◽  
L. Chant ◽  
D. Link
Keyword(s):  
Lake Sediments ◽  
Water Column ◽  
Rate Constant ◽  
Bottom Sediments ◽  
Atmospheric Fallout ◽  
Small Lakes ◽  
Fractional Rate ◽  
Total Input ◽  
Shield Lakes ◽  
Annual Flux

Abstract The average annual flux of Pb-210 from the atmosphere to lake surfaces and to the bottom sediments was measured in seven small lakes located on the Laurentian Shield. Direct atmospheric fallout of Pb-210 was 136 ± 16 Bq m-2 a-1 Streams from the lakes' catchments input an additional 5 to 473 Bq m-2 a-1. Only 16 to 80 percent of the total input was found in the lake sediments. The fractional rate constant for Pb-210 sedimentation from the water column ranged from 0.25 to 5.3 per annum.

Phosphorus Budgets and Stoichiometry during the Open-Water Season in Two Unmanipulated Lakes in the Experimental Lakes Area, Northwestern Ontario

1994 ◽  
Vol 51 (12) ◽  
pp. 2739-2755 ◽  
Author(s):  
P. Campbell
Keyword(s):  
Water Column ◽  
Bottom Sediments ◽  
Open Water ◽  
Short Term ◽  
Experimental Lakes Area ◽  
Northwestern Ontario ◽  
Phosphorus Budgets ◽  
Mass Balance Approach ◽  
Primary And Secondary Producers ◽  
Column Total

A comparative mass-balance approach is used to describe and quantify phosphorus (P) cycles during the open-water season in two unmanipulated Experimental Lakes Area (ELA) lakes. A bimodal cycle generally prevailed, in which water-column total phosphorus (TP = total dissolved P plus sestonic particulate P) peaked just after ice-out and again late in the summer. Changes in mass of water-column TP were often much larger than corresponding net external inputs. Shifts of P to and from either zooplankton or fish in the water column do not explain the P residuals. Rather, the bottom sediments must have been adding P to the water column. Short-term regeneration of P from the bottom sediments also probably occurs in artificially eutrophied ELA lakes. The mechanism of regeneration is probably biological. Other aspects of P cycling and P stoichiometry are discussed, particularly in relation to nutrient control of population structure and the function of primary and secondary producers.

scholarly journals Investigations of the Azov sea ice conditions and assessment of their impact on fishery parameters in winter 2014-2015 using the earth artificial satellites

2017 ◽  
pp. 101-106
Author(s):  
R.V. Borovskaya ◽  
Keyword(s):  
Ice Formation ◽  
Artificial Satellites ◽  
Winter Period ◽  
Short Term ◽  
Mild Winter ◽  
Azov Sea ◽  
The Earth ◽  
Kerch Strait ◽  
Ice Conditions ◽  
Ice Period

Based on the artificial monitoring data, ice conditions of the Azov Sea and Kerch Strait were investigated for the winter period of 2014-2015. The obtained results allowed to conclude that the winter of 2014- 2015 can be regarded as a mild winter, which was due to the fact that cyclones prevailed in the atmospheric circulation. The ice period lasted 99 days from November 23, 2014 (the beginning of ice formation) to March 1,2015 (when the sea was completely free of ice). Ice conditions of the studied area did not affect negatively fish migration and feeding processes in the Kerch Strait, they almost did not prevent fisheries of kilka and so-iuy mullet, except for inconsistent short-term ice situations in the Taganrog and Yasen Bays as well as in the shallow water bights in the northern sea areas.

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