Common cyclicities in the seismicity and water level fluctuations at the Charlevoix seismic zone on the St Lawrence River, Quebec, Canada

A dendrochronological analysis of three tree species colonizing a swamp along the St. Lawrence River was undertaken to (a) study the extent to which water-level fluctuations have an impact on tree growth in comparison to climatic variations; (b) compare the responses of three species (Acerrubrum L., Larixlaricina (Du Roi) K. Koch, and Thujaoccidentalis L.) with hydrologic and climatic variations; and (c) examine the duration of the influence of water-level fluctuations on tree growth. Tree cores from 78 stands were cross-dated and verified with COFECHA and a master chronology for each species was produced using ARSTAN. Response function analyses were used to measure the influence of climate (temperature and precipitation) and water level on tree growth. Water-level fluctuations have a significant influence on A. rubrum growth, accounting for 30% of the tree growth variation. A significant relationship exists between L. laricina and water-level fluctuations, but only 9% of the tree growth is explained by hydrology. No significant relationship was found between water levels and T. occidentalis growth. Climatic fluctuations are a more important influence on growth for all three species, accounting for 46% to 51% of the tree growth variation not explained by water levels.

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Mercury Distribution in an Upper St. Lawrence River Wetland Dominated by Cattail (Typha Angustifolia)

10.21203/rs.3.rs-465123/v1 ◽

2021 ◽

Author(s):

Evie S Brahmstedt ◽

Carla N Ayala Crespo ◽

Thomas M Holsen ◽

Michael Twiss

Keyword(s):

Water Level ◽

Plant Biomass ◽

Management Plan ◽

Hydric Soils ◽

Water Level Fluctuations ◽

Organic Detritus ◽

Riparian Wetland ◽

Water Level Management ◽

Living Tissues ◽

St Lawrence River

Abstract Legacy mercury (Hg) exists in Upper St. Lawrence River wetland hydric soils and is impacted by a new water level management plan (established in 2017) implemented to restore biodiversity and reduce the monotypic nature of riparian wetlands, currently dominated by Typha spp.. The distribution of Hg within the various components of a riparian wetland provides insight into potential impacts of water level fluctuations. Hydric soil represents 83% of the wetland Hg burden while wetland plant biomass contributed 17%, mostly due to organic detritus (13%). Although Typha roots had a bioconcentration factor of 1.2 (relative to hydric soils) and had the highest total Hg among living tissues (25 ± 9.3 ng/g dry wt.), detritus had the highest overall Hg content (110 ± 53 ng/g dry wt.). While root tissue Hg correlated significantly with soil Hg (p = 0.045), it was determined here that Typha spp. has limited use as a biomonitor in wetlands with low levels of Hg contamination, as in this ecosystem. Hg contained within the organic detritus contributed more to the overall Hg burden in these monotypic Typha wetlands than any other tissue or biomass component analyzed. Consequently, shifts in the plant community that are expected to result from a new water level management plan may alter Hg storage within these wetlands and affect its mobility in this ecosystem.

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6. An Investigation of the Spatial Differences in Mercury Burdens of Small Fish in a St-Lawrence River Impoundment Reservoir: the Role of Water Level Fluctuations

Inquiry@Queen's Undergraduate Research Conference Proceedings ◽

10.24908/iqurcp.9081 ◽

2016 ◽

Author(s):

Michele Parisien

Keyword(s):

Water Level ◽

High Water ◽

Water Level Fluctuations ◽

Small Fish ◽

Water Reservoirs ◽

Hydroelectric Reservoirs ◽

Spatial Differences ◽

Reducing Bacteria ◽

St Lawrence River

In many hydroelectric reservoirs across Canada, fish exhibit elevated mercury burdens. This is thought to occur due to the flooding of soil with water level fluctuations. Periods ofhigh water level may cause mercury from shoreline soil to be released into the water, which may make it available for methylation by sulfur-reducing bacteria in the sedimentand phytoplankton on plants. The amount of methylmercury produced during periods of high water level may depend on the topography of the shoreline; if the shoreline has agentle slope, more of its surface area would be covered during rises in water level than if the shoreline has a steep slope. I hypothesize that bays within a reservoir that have a gentle slope and a relatively large amount of vegetation (vegetation provides habitat for periphyton) will have more mercury than steeply-sloped bays with little vegetation. Totest this hypothesis, I have collected 10 each of the 3 most abundant fish (≤100 mm) from 3 bays in eastern Lake St. Lawrence (an impoundment reservoir with water fluctuations ≤2meters throughout the year) at Massena, NY. I will use stable isotopes to infer the trophic level and food web of each fish in order to determine spatial patterns of mercurydistribution. This study may improve our knowledge of mercury methylation patters in water reservoirs, and provide us with information necessary to properly manage the StLawrenceRiver water reservoirs.

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Impact of water level fluctuations on St. Lawrence River aquatic vegetation

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-201 ◽

1997 ◽

Vol 54 (12) ◽

pp. 2853-2865 ◽

Cited By ~ 78

Author(s):

Christiane Hudon

Keyword(s):

Water Level ◽

Aquatic Vegetation ◽

Plant Biomass ◽

Plant Cover ◽

Negative Relationship ◽

Climatic Conditions ◽

Water Levels ◽

Water Level Fluctuations ◽

Vertical Range ◽

St Lawrence River

Historical records of average seasonal water levels in the St. Lawrence River over the past 80 years reveal cyclic variations of up to 1 m above (1976) and 1 m below (1965) present levels. These variations are probably related to climatic conditions in the basin. Over the same period, the vertical range of seasonal water levels decreased from 2.2 to 1.5 m because of discharge regulation. Exposure of new substrate during periods of extreme low water levels may facilitate the invasion of aggressive and (or) exotic species. In Lake Saint-Pierre, a strong negative relationship was observed between seasonal water level and the percentage of emergent plant cover. Under low water levels, the lake becomes a large (387 km2) marshland that could support a high plant biomass (286 times 103 t) whereas under high water levels, the lake shifts to a vast (501 km2) open-water body with a lower predicted plant biomass (117 times 103 t). A model of the major anthropic and climatic forces acting on water levels is also presented; it describes aquatic plant biomass allocation and species diversity under different water level conditions.

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Temperature Trend Analysis in Urmia Lake Basin Compared with Water Level Fluctuations of the Lake

International Institute of Chemical, Biological & Environmental Engineering June 5-6, 2015 Istanbul (Turkey) ◽

10.15242/iicbe.c0615010 ◽

2015 ◽

Keyword(s):

Water Level ◽

Trend Analysis ◽

Temperature Trend ◽

Urmia Lake ◽

Water Level Fluctuations ◽

Lake Basin ◽

Urmia Lake Basin

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AUTOMATIC WATER LEVEL MONITORING WITH IOT AND LPWAN

International Conference on Technics Technologies and Education ◽

10.15547/ictte.2019.02.041 ◽

2019 ◽

pp. 95-103

Author(s):

Krum Videnov ◽

Vanya Stoykova

Keyword(s):

Water Level ◽

Real Time ◽

Early Warning ◽

Water Sources ◽

Water Levels ◽

Water Level Fluctuations ◽

Level Monitoring ◽

Water Level Monitoring

Monitoring water levels of lakes, streams, rivers and other water basins is of essential importance and is a popular measurement for a number of different industries and organisations. Remote water level monitoring helps to provide an early warning feature by sending advance alerts when the water level is increased (reaches a certain threshold). The purpose of this report is to present an affordable solution for measuring water levels in water sources using IoT and LPWAN. The assembled system enables recording of water level fluctuations in real time and storing the collected data on a remote database through LoRaWAN for further processing and analysis.

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