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The use of the 210Pb method for preliminary evaluating the sedimentation rate in Amazon river mouth

100%

Althammer S., Fosshag E., Hoffmann H. M., Nery J. R. C., Bonotto D. M.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2010

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tom 42

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nr 1

149-157

This investigation reports the preliminary results for determining the sedimentation rate at the Amazonas River mouth, Brazil, by the 210Pb method. The CIC (constant initial concentration) of unsupported/excess 210Pb model was successfully applied to one sediments core. The measurements were made in a sediments core comprising ten samples 10 cm – thick each. The year of the sampling (2006) was used as reference for the establishment of the rate of sedimentation from the beginning of the top of the testimony. However, the atmospheric conditions and climate in Amapá State, Brazil, claimed for optimization of the results. Because the Channel North is opened into the Atlantic Ocean, it exhibits a huge water volume, causing a permanent motion of sediments and water. So, heavy waves are formed at the water surface, stirring the upper sand strata. Only at a depth of 40–50 cm the profile tends to be more homogeneous, where it is mostly composed by fine sand and very fine sand. Thus, it is reasonable utilize the CIC model from 210Pb data, which allows estimate a sedimentation rate corresponding to 0.61 g/cm²yr and a mean linear rate of 0.8 cm/yr. The 238U and 210Pb activities in the sediments allowed the reconstruction of the sedimentation processes over a period of about 130 years.

2

Anthropogenic impact on river basins: temporal evolution of sediment classes and accumulation rates in the Northern Tyrrhenian Sea, Italy

75%

Scanu S., Paladini de Mendoza F., Piazzolla D., Marcelli M.

Oceanological and Hydrobiological Studies

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2015

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tom 44

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nr 1

3

Seasonal changes in the white blood cell count and blood cell sedimentation rate in the European bison Bison bonasus

75%

Gill J.

Acta Theriologica

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1992

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tom 37

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nr 3

4

Spatial variability of recent sedimentation rates in the Eastern Gotland Basin (Baltic Sea)

75%

Hille S., Leipe T., Seifert T.

Oceanologia

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2006

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tom 48

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nr 2

In order to study recent sedimentation rates in the Eastern Gotland Basin, 52 short sediment cores collected from the deepest part (<150 m)of the Basin in 2003 were investigated. The upper parts of all the cores were distinctly laminated and dark in colour, followed by a homogeneous, greyish lower part. The thickness of the laminated sequences varied from 17 to 300 mm. 210Pb dating analyses of selected cores revealed that the change from non-laminated to laminated sediments happened about 100 years ago, indicating a shift from predominantly oxic bottom water conditions to anoxic conditions. Used as a time marker, this shift in the sediment texture enabled sediment accumulation rates to be estimated for all sediment cores. The observed mean linear sedimentation rate for the whole basin was 0.93 ± 0.67 mm yr−1. The respective bulk sediment accumulation rates ranged from 10.5 to 527 g m−2 yr−1 with an average of 129 ± 112 g m−2 yr−1, indicating a high spatial variability of sedimentation rates within the basin. This agrees very well with the long-term sedimentation pattern since the Litorina transgression. The observed pattern clearly reflects the hydrographic conditions at the seafloor as studied by modelled near-bottom current velocities.

5

Spatial and temporal variations of sedimentation rate in the Timah Tasoh Water Reservoir, Perlis, Malaysia

63%

Rahaman Z. A., Ismail W. R.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2010

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tom 42

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nr 1

127-138

Human activities such as logging, land conservation, road construction and other disturbances in watersheds will increase erosion rate and thus the amount of sediment transported into the river that reaches lakes, reservoirs and sea. Accelerated sedimentation rate in the reservoir can signifi cantly reduce a reservoir’s surface area, eliminating wetland area surrounding the reservoir and shallow the areas near the shore of the reservoir. A study of sedimentation rate in the Timah Tasoh water reservoir was carried out from May 2001 to April 2002 by means of sediment traps. The aim of this study is to determine the spatial and temporal pattern of sedimentation rates in the reservoir. The sediment traps were installed at five different locations in the reservoir and replaced every month. Gross sedimentation rates measured in the sediment traps vary from about an average of 1.4 kg/m2/month or 16.3 kg/m2/yr in the deepest part of the reservoir to about 79.2 kg/m2/yr (monthly average of 6.6 kg/m2/month) and 47.1 kg/m2/yr (monthly average of 3.9 kg/m2/month) near the inlet of the Pelarit River and the Tasoh River respectively. The sedimentation rate near the Pelarit River and the Tasoh River inflow is correlated with the water and suspended sediment discharge in the river, owing to its proximity to the rivers and the fl ooding effect, mainly during the wet season. The sedimentation rate decreases southward along the reservoir, as a result of increasing distance from the river mouth. The total suspended sediment load of the Upper Pelarit River and the Jarum River flowing into the reservoir is 11.4 × 103 ton/year and 5.41 × 103 ton/ /year respectively.

6

Seasonal changes of sedimentation rates and sediment characteristics status in the Gulf of Mannar Coral Island, India

63%

Yogesh Kumar J. S., Geetha S., Sornaraj R.

International Letters of Natural Sciences

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2014

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tom 01

Corals are known to flourish in various turbid environments around the world. The quantitative distinction between clear and turbid water in coral habitats is not well defined nor are the amount of sediment in suspension and rates of sedimentation used to evaluate the condition of reef environments well established. This study of sedimentation rate, sediment composition and pH, OC deposition was on a fringing reef flat off Thoothukudi and Vembar group of islands, Gulf of Mannar, India. In the present study the sedimentation rate ranged from 1.97 mg/cm2/day to 12.31 mg/cm2/day. The percentage of sand in the sediment was higher than silt and clay. The organic carbon level in all the study stations ranged from 0.03 to 2.54. The sediment pH of the six studied stations was highly acidic in nature at all the study sites in the Gulf of Mannar.

7

Anthropogenic factors, sedimentation rates, vertical movements and the prognoses of the East Baltic Sea development according to the data of comparative sedimentological analysis

63%

Pustelnikovas O.

Oceanological Studies

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2000

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tom 29

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nr 1

8

Health status of rural schoolchildren from Byelorussian Polesye: twenty-years shifts

38%

Verenich G.

Studies of Human Ecology

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1992

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tom 10

Ograniczanie wyników

The use of the 210Pb method for preliminary evaluating the sedimentation rate in Amazon river mouth

Anthropogenic impact on river basins: temporal evolution of sediment classes and accumulation rates in the Northern Tyrrhenian Sea, Italy

Seasonal changes in the white blood cell count and blood cell sedimentation rate in the European bison Bison bonasus

Spatial variability of recent sedimentation rates in the Eastern Gotland Basin (Baltic Sea)

Spatial and temporal variations of sedimentation rate in the Timah Tasoh Water Reservoir, Perlis, Malaysia

Seasonal changes of sedimentation rates and sediment characteristics status in the Gulf of Mannar Coral Island, India

Anthropogenic factors, sedimentation rates, vertical movements and the prognoses of the East Baltic Sea development according to the data of comparative sedimentological analysis

Health status of rural schoolchildren from Byelorussian Polesye: twenty-years shifts