Determination of recent sedimentation rates and pattern in Lake Naini, India by 210Pb and 137Cs dating techniques

AbstractThe biggest problem with most lakes that have no contact with other water sources and are being charged by precipitation is the massive eutrophication. The aim of this work was to determine the sedimentation rate in order to evaluate the progress of eutrophication for St. Ana Lake (Ciomad Mountain near the Băile Tuşnad in Harghita County (Romania)). The concentration of 210Pb was determined by means of high resolution gamma spectrometry as well as derived from 210Po activity which was measured through alpha spectrometry; values obtained are in good agreement. For the excess 210Pb activity values between 4.0±0.5 Bq/kg and 218±20 Bq/kg have been found. As an alternative method, the 137Cs dating method was applied as well. Calculated mass sedimentation rates are in the range of 0.06±0.01 to 0.32±0.05 g/cm2 year with a mean of value of 0.15±0.02 g/cm2 year. Linear sedimentation rates yielded much higher sedimentation values (between 0.5±0.1 and 7.9±0.7 cm/year with a mean of 2.4±0.6 cm/year), due to the predominant organic matter composition and the long suspension time of the sediment. This is an indication for the process of eutrophication which will probably lead to the transformation of the lake into a peat bog.

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The determination of sedimentation rates in Lake Ontario using the 210Pb dating method

Canadian Journal of Earth Sciences ◽

10.1139/e78-047 ◽

1978 ◽

Vol 15 (3) ◽

pp. 431-437 ◽

Cited By ~ 33

Author(s):

John G. Farmer

Keyword(s):

Sedimentation Rate ◽

Lake Ontario ◽

Sedimentary Basins ◽

210Pb Dating ◽

Sedimentation Rates ◽

Surface Mixing ◽

Dating Method ◽

210Pb Dating Method

The 210Pb dating method has been applied successfully to the determination of recent sedimentation rates at four sites distributed among the three major sedimentary basins (Niagara, Mississauga and Rochester) of Lake Ontario. Following correction for effects due to compaction of the sediments, mean sedimentation rates ranging from 0.02 cm/year at the periphery of the Mississauga basin to 0.11 cm/year in the Niagara and Rochester basins were determined. Allowance for compaction reduced the non-compaction-corrected sedimentation rates by 20–35%. Neither 210Pb nor fallout 137Cs profiles indicated surface mixing of sediment sufficient to noticeably affect the calculated sedimentation rates. At all four sites, the sedimentation rate seems to have remained constant during the last 100–150 years.

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Determination of Holocene sedimentation rates from a carbonate lake using excess 226Ra profiles

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2005.12.033 ◽

2006 ◽

Vol 243 (1-2) ◽

pp. 115-127 ◽

Cited By ~ 3

Author(s):

A FAIRCLOUGH ◽

A PLATER ◽

P APPLEBY

Keyword(s):

Sedimentation Rates

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Recent atmospheric lead deposition recorded in an ombrotrophic peat bog of Great Hinggan Mountains, Northeast China, from 210Pb and 137Cs dating

Journal of Environmental Radioactivity ◽

10.1016/j.jenvrad.2010.05.004 ◽

2010 ◽

Vol 101 (9) ◽

pp. 773-779 ◽

Cited By ~ 33

Author(s):

K. Bao ◽

W. Xia ◽

X. Lu ◽

G. Wang

Keyword(s):

Northeast China ◽

Peat Bog ◽

210Pb And 137Cs ◽

137Cs Dating ◽

Ombrotrophic Peat

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Chemical indicators of sediment chronology

Marine and Freshwater Research ◽

10.1071/mf9930635 ◽

1993 ◽

Vol 44 (4) ◽

pp. 635 ◽

Cited By ~ 19

Author(s):

GW Kilby ◽

GE Batley

Keyword(s):

Urban Areas ◽

Sewage Treatment ◽

Alternative Methods ◽

Chemical Components ◽

Sedimentation Rates ◽

Antifouling Paints ◽

Chemical Indicators ◽

Laboratory Facilities ◽

Lead Zinc

The determination of recent sedimentation rates has traditionally used radiochemical dating techniques but, because of limited laboratory facilities and the costs of these techniques, alternative methods are desirable. Information on sedimentation rates and sediment history can be obtained from anthropogenic chemical components whose presence in sediments, especially near urban areas, can be used as markers to assess their chronology. More than one marker, with a known date of introduction, should be used. In this study, organosilicons first used in the early 1950s and tributyltin used in marine antifouling paints from 1972 were examined in sediments from Lake Macquarie, NSW, to supplement the known input of heavy metals from the lead-zinc smelter that has been operating at the northern end of the lake since 1897. The most reliable data were obtained at sites where all three markers were present, and use of these data allowed independent determination of the year of initial operation of a sewage treatment works.

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Physical and physiological components of the graviresponses of wild-type and mutant Paramecium Tetraurelia

Journal of Experimental Biology ◽

10.1242/jeb.203.6.1059 ◽

2000 ◽

Vol 203 (6) ◽

pp. 1059-1070 ◽

Cited By ~ 2

Author(s):

U. Nagel ◽

H. Machemer

Keyword(s):

Swimming Speed ◽

Sedimentation Rates ◽

Paramecium Tetraurelia ◽

Wild Type ◽

Centre Of Gravity ◽

In The Wild ◽

Type Population ◽

G Value ◽

Mutant Cells

Wild-type and the morphological mutant kin 241 of Paramecium tetraurelia showed improved orientation away from the centre of gravity (negative gravitaxis) when accelerations were increased from 1 to 7 g. Gravitaxis was more pronounced in the mutant. A correlation between the efficiency of orientation and the applied g value suggests a physical basis for gravitaxis. Transiently enhanced rates of reversal of the swimming direction coincided with transiently enhanced gravitaxis because reversals occurred more often in downward swimmers than in upward swimmers. The results provide evidence of a physiological modulation of gravitaxis by means of the randomizing effect of depolarization-dependent swimming reversals. Gravity bimodally altered propulsion rates of wild-type P. tetraurelia so that sedimentation was partly antagonized in upward and downward swimmers (negative gravikinesis). In the mutant, only increases in propulsion were observed, although the orientation-dependent sensitivity of the gravikinetic response was the same as in the wild-type population. Observed swimming speed and sedimentation rates in the wild-type and mutant cells were linearly related to acceleration, allowing the determination of gravikinesis as a linear (and so far non-saturating) function of gravity.

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