An historical assessment of trace metal accumulation in Lake Champlain, Vermont

Conference · Mon Mar 01 00:00:00 EST 1993 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5508455

Mecray, E L; King, J W ^[1]

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1. Univ. of Rhode Island, Narragansett, RI (United States). Graduate School of Oceanography

The Lake Champlain watershed, with its increased land use, shoreline development, and population, is being threatened by pollutants in the water column and bottom sediments. A comprehensive study is currently being conducted to characterize the bottom sediments of the lake for toxicity and to reconstruct the history of pollutant inputs. Surface sediment samples were collected from 30 stations and analyzed for metal (Cu, Zn, Cr, Pb, Ni, Mn, Fe, Cd, Al, and Ag) concentrations to determine the contaminated regions of the lake. Once the contaminated regions were determined, a Nemesis corer was used to retrieve sediments cores averaging 1 meter in length from 10 sites within Lake Champlain. Grain size and metal analyses were conducted at one and two cm intervals down the cores. Grain size data, in combination with metal and radiometric stratigraphy, can serve as an indicator of changing land use in the watershed. The grain size in some cores has a fining upward trend indicating increased land use and soil erosion. Downcore variations in metal concentrations reveal two different regimes. The concentration at depth remain consistently low and are inferred to correspond with the natural background levels. In contrast, the upper section of the cores show abrupt increases in metal concentrations which are attributed to increased anthropogenic inputs. Radiometric ([sup 210] and [sup 137]Cs) and pollen chronostratigraphy of these cores indicates that the increased metal concentrations and the changes in grain size recorded in the upper most sediments is related to increased human disturbance beginning in the late 18th and early 19th centuries. This study demonstrates that the historical record of pollution inputs to Lake Champlain can be reconstructed from the sediment sequences.

• OSTI ID: 5508455
• Report Number(s): CONF-9303211-; CODEN: GAAPBC; TRN: 94-001056
• Journal Information: Geological Society of America, Abstracts with Programs; (United States), Vol. 25:2; Conference: 28. annual Geological Society of America (GSA) Northeastern Section meeting, Burlington, VT (United States), 22-24 Mar 1993; ISSN 0016-7592
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
LAKES
SEDIMENTS
WATER POLLUTION
CHEMICAL COMPOSITION
TRANSITION ELEMENTS
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL TRANSPORT
VERMONT
HISTORICAL ASPECTS
LAND USE
POLLUTANTS
TRACE AMOUNTS
WATERSHEDS
DEVELOPED COUNTRIES
ELEMENTS
MASS TRANSFER
METALS
NORTH AMERICA
POLLUTION
SURFACE WATERS
USA
540250* - Environment
Terrestrial- Site Resource & Use Studies- (1990-)
540350 - Environment
Aquatic- Site Resource & Use Studies- (1990-)
540230 - Environment
Terrestrial- Radioactive Materials Monitoring & Transport- (1990-)
540330 - Environment
Aquatic- Radioactive Materials Monitoring & Transport- (1990-)