Cultural Impact on the Geochemistry of Sediments in Lake Erie

1976 ◽  
Vol 33 (3) ◽  
pp. 440-462 ◽  
Author(s):  
A. L. W. Kemp ◽  
R. L. Thomas ◽  
C. I. Dell ◽  
J.-M. Jaquet

The chemical and physical characteristics of six cores from Lake Erie are described. The concentrations of Si, Al, K, Na, and Mg, which represent the major mineral species in the sediment, were uniform in each core. Surface enrichments of Hg, Pb, Zn, Cd, Cu, Organic-C, N, and P were observed at each location, due mainly to the increasing anthropogenic loading of these elements to the sediments since 1850. Concentration profiles for Mn, Fe, and S were related to sediment Eh and are due to mobilization of these elements in the pore waters.Natural and anthropogenic inputs of nutrients and heavy metals were calculated. About 60% of the total loading of these elements is being deposited in the Eastern basin. It is calculated that 30 million metric tons of fine-grained sediment accumulates in the offshore basins of the lake, each year. The major source of the sediment input is erosion of the shoreline bluffs, with the north shore between Erieau and Long Point contributing 21 million metric tons annually. A sediment mass balance suggests that a large part of this bluff material is transported up to 150 km and is deposited in the Eastern basin.

2015 ◽  
Vol 129 (1) ◽  
pp. 80 ◽  
Author(s):  
Jordan Catrysse ◽  
Emily Slavik ◽  
Jonathan Choquette ◽  
Ashley E. Leifso ◽  
Christina M. Davy

We report a mass mortality of Northern Map Turtles (Graptemys geographica [LeSueur, 1817]) on the north shore of Lake Erie, Ontario, Canada. Thirty-five dead adult females were recovered from a nesting area over a period of four weeks. Predation and boat strikes were both excluded as potential cause of death, but the actual cause could not be determined because of the poor condition of the carcasses. Other possible explanations for the mortality include poisoning, drowning, and infection with an unidentified pathogen. Mass mortality in long-lived species, such as turtles, can have long-term effects on population growth and is a cause for concern in a species at risk.


1950 ◽  
Vol 82 (12) ◽  
pp. 250-252 ◽  
Author(s):  
W. W. Judd

On July 12, 1950 a collection of adults of the moth Acentropus niveus (Oliv.) was made on the north shore of Lake Erie near the village of South Cayuga, Ontario (Maps A, B-3). At the southern limits of the townships of Dunn and South Cayuga (Haldimand County) a shallow bay extends for a distance of about two miles along the shore of the lake (Map A). Along this bay is a sandy or gravelly beach ten to twenty yards wide backed by a cliff of clay that rises abruptly above the beach. On the day the collections were made the sky was clear and a brisk southerly breeze was causing waves to wash on the beach. The action of the waves had deposited debris, consisting largely of tangled masses of a filamentous green alga and exuviae of the mayfly Hexagenia occulta, in a windrow six inches to two feet wide along the shore. The moths ere found in this debris, most of them lying dead and with bedraggled wings, while some lay on their backs with wings stuck to the damp surface and with legs kicking and a few were crawling about on the debris.


1982 ◽  
Vol 39 (5) ◽  
pp. 748-759 ◽  
Author(s):  
J. Bloesch

From June through October 1978 sediment traps were moored at three stations in an inshore–offshore transect in the Eastern Basin of Lake Erie. Settling fluxes measured with the traps exposed close to lake bottom were rather similar at all three stations during summer stratification, averaging 6.1 g∙m−2∙d−1 for dry weight, 293 mg∙m−2∙d−1 for particulate organic carbon (POC), 38 mg∙m−2∙d−1 for particulate nitrogen (PN), and 5.44 mg∙m−2∙d−1 for particulate phosphorus (PP). A comparison of the hypolimnetic traps with the epilimnetic traps at the offshore station indicated that considerable resuspension takes place even in summer. During fall, however, the nearshore sedimentation rates were markedly increased because of storm-induced bottom resuspension. By comparing the trap catches with sediment cores taken at all three stations, a resuspension model for dry weight, POC, and PN was developed. The calculations showed that newly formed organic material is resuspended and redeposited more frequently at nearshore locations than offshore. This repeated nearshore resuspension enhances decomposition of detritus, as shown by low relative phytoplankton activity in the hypolimnetic traps, and results in horizontal transport of fine-grained organic matter in the offshore direction. The significant POC and PN concentration differences found in the inshore–offshore transect of the bottom sediments can be explained by these two processes.Key words: sedimentation, sediment traps, sediment cores, resuspension, inshore–offshore differences


1966 ◽  
Vol 23 (2) ◽  
pp. 275-291 ◽  
Author(s):  
A. H. Berst ◽  
H. R. McCrimmon

Long Point Bay, on the north shore of Lake Erie, is 28.2 square miles (7278 hectares) in area, with a maximum depth of approximately 10 ft (3.05 m). Big Creek, the major tributary, drains a watershed of 317 square miles (81,818 hectares), and discharges 4700 million cubic feet (127,000 million liters) of water into the Bay annually. Summer water temperatures in the Creek and the Bay were positively correlated with air temperatures in 1962. The water in the Bay was subject to considerable seiche action. Levels of nutrients and suspended materials were characteristically higher in the Creek than in the Bay. Gross reductions in levels of turbidity, total dissolved solids, nitrates, and phosphates occurred in the lower section of Big Creek and the adjacent area of the Bay. For example, phosphate levels of bottom samples were inversely correlated with those of water samples in lower Big Creek and its estuary. The path of Big Creek discharge through the Bay to Lake Erie was defined by an analysis of total dissolved solids and soil phosphate data.


2006 ◽  
Vol 63 (7) ◽  
pp. 1549-1563 ◽  
Author(s):  
Richard P Barbiero ◽  
David C Rockwell ◽  
Glenn J Warren ◽  
Marc L Tuchman

Distinct changes have occurred in the size and composition of the spring phytoplankton community in the eastern basin of Lake Erie following the introduction of Dreissena. Since 1996, total phytoplankton biovolume has decreased to approximately 20% of pre-Dreissena levels, whereas postinvasion concentrations of spring soluble nutrients, particularly silica, have been substantially elevated compared with earlier years. Spring dominance has shifted from a mix of pennate and large centric diatoms and pyrrophytes to three centric diatoms with high silica requirements: Aulacoseira islandica, Stephanodiscus hantzschii, and Stephanodiscus parvus, and the overall diversity and species richness of the spring phytoplankton community has declined significantly. In addition, current April silica concentrations are approximately twice as high as historical (i.e., 1960s–1980s) winter maxima, indicating that the silica content of the lake has increased since the dreissenid invasion. These results suggest that the severe silica depletion caused by increased anthropogenic inputs of nutrients during the last century has been mitigated through a decrease in diatom production, most likely brought about by dreissenid grazing.


2014 ◽  
Vol 40 (1) ◽  
pp. 187-191 ◽  
Author(s):  
Yerubandi R. Rao ◽  
Todd Howell ◽  
Susan B. Watson ◽  
Scott Abernethy
Keyword(s):  

1977 ◽  
Vol 14 (3) ◽  
pp. 310-323 ◽  
Author(s):  
R. M. Quigley ◽  
P. J. Gelinas ◽  
W. T. Bou ◽  
R. W. Packer

The 27–45 m high bluffs along the north shore of Lake Erie in Ontario are retreating inland at a 150 year average rate of 0.5 to 3.0 m/year. The retreat mechanisms and rates are cyclic and consist of complex interrelationships of toe erosion by wave attack, cliff steepening, sheet sloughing, and landsliding associated with softening in response to changes in effective stress. Four cyclic failure types are presented.1. Slowly retreating (0.6 m/year) unvegetated cliff fronts of 27 m height and nearly constant profile associated with low energy wave attack (0.5 kW/m) at the toe and cyclic sheet sloughing caused by desiccation and wetting at monthly intervals. Landsliding very rare and surficial.2. Cliffs of 34 m height retreating at intermediate rates (1.4 m/year) showing cyclic changes in profile in response to major, cyclic landslides. Retreat mechanisms involve toe erosion by intermediate energy wave attack (1.0 kW/m) and large toe failures at 10–20 year intervals in response to softening and changes in effective stress.3. Cliffs of 42 m height retreating at 2.8 m/year showing cyclic changes in profile in response to major, high velocity, cyclic landslides that deposit offshore fans of slide debris that provide erosion protection but no counterbalancing moment protection. Toe sands play a significant role, enabling undercutting by high energy wave attack (~2 kW/m). Size and frequency of landslides too variable to quantify at present.4. Cliffs of 38–45 m height retreating at 2.0 m/year in response to toe erosion under high energy wave attack (2 kW/m). Thick water bearing surface sands cause sloughing and shallow failure of the upper slopes at 1.5 year intervals above near vertical wave cut toe cliffs. Huge, deep seated failures may develop during periods of cyclic low water level at roughly estimated intervals of 30 years.


2014 ◽  
Vol 128 (2) ◽  
pp. 135 ◽  
Author(s):  
Claire E. Sanders ◽  
Daniel J. Mennill

Understanding the flight patterns of migrating birds is critical for informing conservation actions and management decisions. We studied the geographic and temporal distribution of birds migrating through the southern Great Lakes using nocturnal acoustic monitoring data and banding records from sites on Pelee Island in Lake Erie and on the mainland along the north shore of Lake Erie. Given that Lake Erie may represent an ecological barrier to migratory birds, we predicted that mainland and island sites would show different patterns in both the number of passage migrants and the timing of their migration. Analysis of over 60,000 flight calls from 6200 h of recordings revealed significantly more migrants over the island than the mainland in both spring and fall 2012. The acoustic data provide evidence that none of the species or species groups examined avoided crossing the lake. Birds were detected significantly earlier on Pelee Island than on the north shore of Lake Erie in spring, although they were not detected earlier on the mainland in fall. These results suggest that Lake Erie is not a major barrier to migration. The large number of birds detected over the island suggest that birds may concentrate their flight over islands in the middle of the lake, although recordings of migrants over open water will be required to support this suggestion. Our results show that Pelee Island is an important part of the migratory route of North American birds and provide valuable information on the movement of nocturnal migrants over the Great Lakes.


2007 ◽  
Vol 43 (1) ◽  
pp. 65-76 ◽  
Author(s):  
J. P. Coakley

ABSTRACT The origin of Pointe-aux-Pins, a large, rounded, cuspate foreland protruding from the north shore of Lake Erie, is difficult to explain by conventional spit formation processes. Stratigraphic evidence from boreholes, the distribution of nearshore sediments, surface geomorphology, and previously published interpretations of Lake Erie water levels were combined to produce an hypothetical model of the development of the foreland from approximately 12,000 years BP to now. According to the model, the ancestral Pointe-aux-Pins began as a promontory caused by the intersection of the cross-lake Erieau moraine with the original lake shoreline, then located tens of kilometres lakeward of its present position. Lake levels at the time were about 30 m below present datum (173.3 m a.s.l.). Modern Pointe-aux-Pins dates from after the Nipissing "flood", at about 3500 BP, when the thereto-submerged sandy spit platform was again subjected to wave action, leading to beach ridge and dune formation. The age of the foreland of 3500 to 4000 years compares well with estimates based on the annual sand supply rate and the present sand volume in Pointe-aux-Pins.


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