Lake Management Based on Lime Application and Hypolimnetic Oxygenation: the Experience in Eutrophic Hardwater Lakes in Alberta

1997 ◽  
Vol 32 (2) ◽  
pp. 273-294 ◽  
Author(s):  
Ellie E. Prepas ◽  
Tom P. Murphy ◽  
W. Paul Dinsmore ◽  
Janice M. Burke ◽  
Patricia A. Chambers ◽  
...  
Keyword(s):  
Thermal Stratification ◽  
Lake Management ◽  
Chl A ◽  
Hypolimnetic Oxygenation ◽  
Retention Basins ◽  
Flushing Rates ◽  
Lime Application ◽  
Phosphorus Recycling ◽  
Management Alternatives ◽  
Stormwater Retention

Abstract Many water bodies in western Canada experience high internal phosphorus recycling rates and excessive primary production, with associated water column anoxia and restricted fisheries habitat. Lime (Ca(OH)2 and CaCO3) application and hypolimnetic oxygenation were investigated in Alberta as nontoxic, inexpensive management alternatives. In hardwater lakes, multiple Ca(OH)2 applications at dosages <100 mg L-1 reduced chl a and TP concentrations by up to ~30 and 50%, respectively, often for several years. In contrast, high flushing rates in stormwater retention basins made repeated Ca(OH)2 treatment necessary. Hypolimnetic oxygenation in Amisk Lake from 1988-93 increased hypolimnetic dissolved oxygen concentrations from 0.9 to 4.6 mgL-1 in the treated basin while maintaining thermal stratification. Epilimnetic whole-lake chl a and TP concentrations were reduced by 55 and 13%, respectively. Deep-water habitat was improved for fish, zooplankton and macroinvertebrates. Our research shows that water quality can be improved in lakes that are naturally eutrophic (i.e., due to internal P cycling) and has implications for lake management projects worldwide.

Iron plays a role in nitrate drawdown by phytoplankton in Lake Erie surface waters as observed in lake-wide assessments

2012 ◽  
Vol 69 (2) ◽  
pp. 369-381 ◽  
Author(s):  
Sonya M. Havens ◽  
Christel S. Hassler ◽  
Rebecca L. North ◽  
Stephanie J. Guildford ◽  
Greg Silsbe ◽  
...  
Keyword(s):  
Surface Waters ◽  
Thermal Stratification ◽  
Lake Erie ◽  
Phytoplankton Community ◽  
Sampling Depth ◽  
Phytoplankton Pigment ◽  
Chl A ◽  
Dissolved Iron ◽  
Continuous Surface

Phytoplankton interactions with iron (Fe) were examined in surface waters of Lake Erie during summer thermal stratification. Lake-wide sampling in June and September 2005 was conducted using a continuous surface water sampler (1 m sampling depth) and in July at 18 hydrographic stations (5 m sampling depth). In situ measurements of photosynthetic efficiency (maximum quantum yield of photosystem II) and phytoplankton community composition were measured using fast repetition rate fluorometry and a phytoplankton pigment-specific fluorometer, respectively, during June and September. High ratios (73%–85%) of intracellular Fe to particulate Fe coincident with increases in chlorophyll a (Chl a) concentrations in the western and central basins in June and July imply that the majority of Fe in these regions was associated with intracellular pools. Correlations between intracellular Fe and Chl a were frequently observed when Heterokontophyta and Pyrrophyta dominated the phytoplankton community. Assimilation of Fe by the phytoplankton strongly influenced its partitioning between the dissolved and particulate phase. Dissolved iron (<0.45 µm) concentrations were proportional to Chl a concentrations and both dissolved iron and Chl a were inversely proportional to nitrate concentrations in July and September, suggesting that dissolved iron influenced both nitrate drawdown and Chl a concentrations in Lake Erie surface waters in summer.

Dynamic Evaluation of Frank Lake Management Alternatives

WRPMD'99 ◽  
1999 ◽  
Author(s):  
Michael Bender ◽  
Mark Digel ◽  
Alan Pentney
Keyword(s):  
Lake Management ◽  
Dynamic Evaluation ◽  
Management Alternatives

Influence of extended water column mixing during the first 2 years of hypolimnetic oxygenation on the phytoplankton community of Amisk Lake, Alberta

1997 ◽  
Vol 54 (9) ◽  
pp. 2133-2145 ◽  
Author(s):  
D J Webb ◽  
R D Robarts ◽  
E E Prepas
Keyword(s):  
Water Column ◽  
Trophic Status ◽  
Phytoplankton Community ◽  
Euphotic Zone ◽  
Open Water ◽  
Eutrophic Lake ◽  
Cyanobacterial Blooms ◽  
Chl A ◽  
Hypolimnetic Oxygenation ◽  
Physical Variables

The phytoplankton community, physical variables, and nutrient and chlorophyll a (Chl a) concentrations were monitored during the first two of six open-water seasons of hypolimnetic oxygenation in double-basined Amisk Lake, Alberta. Deep mixing of the water column in the treated basin (Zmax = 34 m) in spring was enhanced by hypolimnetic oxygenation. Oxygenation began in June 1988, when stratification was likely already established, but subsequent year-round treatment favoured an extended spring diatom bloom (Asterionella formosa and Cyclotella spp.), followed by a delay in the development of, and reduction in the severity of, cyanobacterial blooms (Aphanizomenon flos-aquae and Anabaena flos-aquae) in 1989. Historically, mean summer Chl a and total phosphorus (TP) concentrations in the euphotic zone (0-6 m) of the treated basin were 15.9 ± 1.6 and 33.5 ± 1.5 µg ·L-1, respectively, indicating a eutrophic lake. In 1988 and 1989, mean summer Chl a (10.0 ± 0.6 and 8.1 ± 0.7 µg ·L-1, respectively) and TP concentrations (29.0 ± 0.5 and 22.5 ± 0.9 µg ·L-1, respectively) in this stratum were lower than historic values (P < 0.05), indicating that the trophic status of Amisk Lake had shifted towards mesotrophy.

Phosphorus–Chlorophyll Relationships under Contrasting Herbivory and Thermal Stratification: Predictions and Patterns

1994 ◽  
Vol 51 (2) ◽  
pp. 390-400 ◽  
Author(s):  
Asit Mazumder
Keyword(s):  
Chlorophyll A ◽  
Total Phosphorus ◽  
Aquatic Ecosystems ◽  
Thermal Stratification ◽  
Lake Management ◽  
Lake Ecosystems ◽  
Temperate Lake ◽  
Variable Chemical ◽  
Herbivore Communities ◽  
Mixed Systems

Analyses of the relationships between total phosphorus (TP) and chlorophyll a (Chl) among a large number of temperate lake ecosystems having contrasting herbivore communities and thermal stratification reveal that systems lacking large Daphnia (SH systems) exhibit four times more Chl yields than systems having large Daphnia (LH systems) in oligotrophic as well as eutrophic and hypereutrophic systems. Mixed (MIX) systems exhibit greater Chl yields than stratified (STR) systems. Within each group of stratified and mixed systems, greater Chl yields to constant TP are observed in systems lacking large Daphnia (MIX-SH and STR-SH) than those having large Daphnia (MIX-LH and STR-LH). Consequently, a hierarchy of Chl yield patterns is produced; STR-LH and MIX-SH systems exhibit the lowest and highest Chl yields, respectively, at constant TP. These patterns may be a reflection of variable chemical (nutrients), biological (herbivory), and physical (thermal stratification) characteristics among aquatic ecosystems. Sigmoid patterns of TP–Chl relationships appear to be related to the transition from stratified to mixed systems along the TP gradient. The finding that highly variable Chl yields to TP can be summarized into a set of TP–Chl trajectories for specific types of lake ecosystems may have strong implications for lake management.

scholarly journals A large CO<sub>2</sub> sink enhanced by eutrophication in a tropical coastal embayment (Guanabara Bay, Rio de Janeiro, Brazil)

2015 ◽  
Vol 12 (6) ◽  
pp. 4671-4720 ◽  
Author(s):  
L. C. Cotovicz ◽  
B. A. Knoppers ◽  
N. Brandini ◽  
S. J. Costa Santos ◽  
G. Abril
Keyword(s):  
Rio De Janeiro ◽  
Thermal Stratification ◽  
Carbon Sink ◽  
Atmospheric Co2 ◽  
Guanabara Bay ◽  
Small Surface ◽  
Tropical Regions ◽  
Chl A ◽  
Se Brazil ◽  
Organic Carbon Burial

Abstract. In contrast to its small surface area, the coastal zone plays a disproportionate role in the global carbon cycle. Carbon production, transformation, emission and burial rates at the land–ocean interface are still poorly known, especially in tropical regions. Surface water pCO2 and ancillary parameters were monitored during nine field campaigns between April 2013 and April 2014 in Guanabara Bay, a tropical eutrophic to hypertrophic semi-enclosed estuarine embayment surrounded by the city of Rio de Janeiro, SE-Brazil. Water pCO2 varied between 22 and 3715 ppmv in the Bay showing spatial, diurnal and seasonal trends that mirrored those of dissolved oxygen (DO) and Chlorophyll a (Chl a). Marked pCO2 undersaturation was prevalent in the shallow, confined and thermally stratified waters of the upper bay, whereas pCO2 oversaturation was restricted to sites close to the small river mouths and small sewage channels, which covered only 10% of the bay's area. Substantial daily variations in pCO2 (up to 395 ppmv between dawn and dusk) were also registered and could be integrated temporally and spatially for the establishment of net diurnal, seasonal and annual CO2 fluxes. In contrast to other estuaries worldwide, Guanabara Bay behaved as a net sink of atmospheric CO2, a property enhanced by the concomitant effects of strong radiation intensity, thermal stratification, and high availability of nutrients, which promotes phytoplankton development and net autotrophy. In the inner part of the bay, the calculated annual CO2 sink (−19.6 mol C m2 yr-1) matched the organic carbon burial in the sediments reported in the literature. The carbon sink and autotrophy of Guanabara Bay was driven by planktonic primary production promoted by eutrophication, and by its typology of marine embayment lacking the classical extended estuarine mixing zone, in contrast to river-dominated estuarine systems, which are generally net heterotrophic and CO2 emitters. Our results show that global CO2 budgetary assertions still lack information on tropical estuarine embayments and lagoons, which are affected by thermal stratification and eutrophication and behave specifically with respect to atmospheric CO2.

scholarly journals Temperature Profiling of Waterbodies with a UAV-Integrated Sensor Subsystem

Drones ◽  
2020 ◽  
Vol 4 (3) ◽  
pp. 35
Author(s):  
Cengiz Koparan ◽  
Ali Bulent Koc ◽  
Calvin Sawyer ◽  
Charles Privette
Keyword(s):  
Surface Water ◽  
Water Temperature ◽  
Autonomous Navigation ◽  
Water Surface ◽  
Thermal Stratification ◽  
Lake Management ◽  
Temperature Measurements ◽  
Surface Water Temperature ◽  
Average Water Temperature ◽  
Integrated Sensor

Evaluation of thermal stratification and systematic monitoring of water temperature are required for lake management. Water temperature profiling requires temperature measurements through a water column to assess the level of thermal stratification which impacts oxygen content, microbial growth, and distribution of fish. The objective of this research was to develop and assess the functions of a water temperature profiling system mounted on a multirotor unmanned aerial vehicle (UAV). The buoyancy apparatus mounted on the UAV allowed vertical takeoff and landing on the water surface for in situ measurements. The sensor node that was integrated with the UAV consisted of a microcontroller unit, a temperature sensor, and a pressure sensor. The system measured water temperature and depth from seven pre-selected locations in a lake using autonomous navigation with autopilot control. Measurements at 100 ms intervals were made while the UAV was descending at 2 m/s until it landed on water surface. Water temperature maps of three consecutive depths at each location were created from the measurements. The average surface water temperature at 0.3 m was 22.5 °C, while the average water temperature at 4 m depth was 21.5 °C. The UAV-based profiling system developed successfully performed autonomous water temperature measurements within a lake.

Ecotoxicological characterisation of sediments from stormwater retention basins

2014 ◽  
Vol 69 (5) ◽  
pp. 1045-1051 ◽  
Author(s):  
C. Gonzalez-Merchan ◽  
Y. Perrodin ◽  
C. Sébastian ◽  
C. Bazin ◽  
T. Winiarski ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Interstitial Water ◽  
Solid Phase ◽  
Toxic Effects ◽  
Term Operation ◽  
Retention Basins ◽  
Detention Basins ◽  
Stormwater Retention ◽  
Battery Of Bioassays

Retention–detention basins are important structures for managing stormwater. However, their long-term operation raises the problem of managing the sediments they accumulate. Potential uses for such sediments have been envisaged, but each sediment must be characterised beforehand to verify its harmlessness. In this paper we address this issue through the development of a battery of bioassays specifically adapted to such sediments. We tested the method on samples taken from four retention basins in the region of Lyon (France). This battery focuses on the toxic effects linked to both the solid phase (ostracod and Microtox® solid-phase tests) and the liquid-phase (interstitial water) of sediments (rotifer and Microtox® liquid-phase tests). The results obtained permit the sorting of sediments presenting little toxicity, and which could therefore be potentially exploitable, from those from more polluted areas presenting higher toxicity that limits their use.

Sign in / Sign up

Export Citation Format

Share Document