Physical, Chemical, and Biological Characteristics of the Turkey Lakes Watershed, Central Ontario, Canada

1988 ◽  
Vol 45 (S1) ◽  
pp. s3-s13 ◽  
Author(s):  
Dean S. Jeffries ◽  
John R. M. Kelso ◽  
Ian K. Morrison
Keyword(s):  
Sugar Maple ◽  
Forest Type ◽  
Oxygen Depletion ◽  
Water Composition ◽  
Limiting Nutrient ◽  
Bottom Waters ◽  
Turkey Lakes Watershed ◽  
A Chain ◽  
A Site ◽  
High Elevations

The Turkey Lakes Watershed (TLW) in central Ontario was selected for intensive research into the effects of the long-range transport of air pollutants (primarily acidic deposition) at a site on the Canadian Shield having both vulnerable terrain and an undisturbed Great Lakes forest type. The terrestrial and aquatic resources within the basin are representative of the surrounding region of Algoma, although for Ontario, it does have high relief (290 m) and high annual precipitation (>1200 mm). The TLW contains a chain of four lakes (five distinct lake basins) that range from 5.8 to 52.0 ha in area and 2.2 to 12.2 m in mean depth. The lakes are dimictic and, except for the deepest lake, experience dissolved oxygen depletion in undisturbed bottom waters. There is a gradient in the major ion composition of lakes within the TLW, the most dilute waters occurring at high elevations. Calcium levels increase from 55 to 138 μmol∙L−1 down the chain. Sulphate is the dominant lake water anion in the headwater lake, while alkalinity dominates in the lowest lake. Phosphorus is the limiting nutrient in these lakes; NO3-N levels are relatively high (7.9–16.4 μmol∙L−1) because the terrestrial basin exhibits low utilization of this nitrogen species. Seasonal and episodic variations in surface water composition can be large. The headwater lake contains no fish; however, fish communities in the lower three lakes (composed of 8-11 species) are typical of the Algoma region. The distribution of benthic organisms is primarily a function of lake depth and presence/absence of fish rather than variations in water chemistry. Zooplankton species composition is similar across all lakes, and cyanophytes are the dominant algae throughout. The forest is an uneven-aged, mature-to-overmature, old-growth tolerant hardwood stand. The principal tree species is sugar maple (90%) with lesser amounts of other hardwoods (9%, usually yellow birch) and various conifers (1%). Production is typical of forest at this northerly latitude (47°N). Foliar bioelement concentrations are generally similar to those observed at Hubbard Brook, New Hampshire.

scholarly journals Forest research at the Turkey Lakes Watershed

1999 ◽  
Vol 75 (3) ◽  
pp. 395-399 ◽  
Author(s):  
I. K. Morrison ◽  
D. A. Cameron ◽  
N. W. Foster ◽  
A. Groot
Keyword(s):  
Sugar Maple ◽  
Climate Models ◽  
Precipitation Chemistry ◽  
Forest Growth ◽  
Soil Productivity ◽  
Single Tree Selection ◽  
Turkey Lakes Watershed ◽  
A Site ◽  
Interdisciplinary Study ◽  
Relationship Of

The 10.5 km2 Turkey Lakes Watershed, located on the Precambrian Shield approximately 60 km north of Sault Ste. Marie, Ontario, is occupied by a typical Great Lakes-St. Lawrence sugar maple-yellow birch forest. Since late 1979, the watershed has been the site of an interdisciplinary study on impacts of long-range transported air pollutants on the biology of forests, lakes and streams, and the recovery of terrestrial and aquatic ecosystems in response to reduced pollutant deposition. A knowledge base on forest growth, soils and hydrology, with detailed climate and precipitation chemistry records dating back nearly twenty years has been developed. This history, plus an available infrastructure, makes the watershed an ideal site to study processes across the terrestrial-aquatic interface. A harvesting impacts project, for example, was started in 1997. This project is built around a field experiment comparing clear-felling, shelterwood, and single-tree selection versus uncut control, for appropriateness of application and for impacts on long-term soil productivity, stand function, diversity of plant and animal life, and hydrological and other on- and off-site impacts. The watershed is also a site for the ECOLEAP Project, which is attempting to improve overall understanding of mechanisms controlling forest productivity, and a site to test terrain and climate models to model temperature, moisture, energy and nutrients and the relationship of these to species distribution, abundance and productivity at different scales up to the watershed level. Key words: acid precipitation, air pollution, biogeochemistry, research site, watershed

Influence of restoration methods on the longevity of changes in the thermal and oxygen dynamics of a degraded lake

2015 ◽  
Vol 44 (1) ◽  
Author(s):  
Jolanta Grochowska ◽  
Renata Brzozowska ◽  
Michał Łopata ◽  
Julita Dunalska
Keyword(s):  
Oxygen Depletion ◽  
Artificial Circulation ◽  
Anaerobic Conditions ◽  
Lake Volume ◽  
Depletion Rate ◽  
Bottom Waters ◽  
Phosphorus Inactivation ◽  
The City ◽  
Oxygen Dynamics ◽  
Content Of Oxygen

AbstractThe study was conducted on Lake Długie, located in the city of Olsztyn, which for 20 years received raw domestic sewage (400 m3 per day). After preliminary conservation operations, the lake was restored by artificial circulation and phosphorus inactivation methods. During artificial circulation, water temperature in the whole lake volume was equalized. The disconnection of the compressor stimulated the return to typical thermal parameters in the lake. Phosphorus inactivation did not affect the thermal regime in the lake. Artificial circulation caused an increase in the oxygen content in the whole lake, lowered the oxygen-depletion rate during stagnation, and shortened the duration of anaerobic conditions in the near-bottom waters. Phosphorus inactivation did not directly affect the content of oxygen. However, after the coagulant was added to the lake, the oxygenation of the water was further improved owing to the depressed photosynthesis caused by drastically reduced availability of phosphate for primary producers.

Liebig’s Law and Haber’s Tragedy

Dead Zones ◽  
2021 ◽  
pp. 89-105
Author(s):  
David L. Kirchman
Keyword(s):  
Gulf Of Mexico ◽  
Chesapeake Bay ◽  
19Th Century ◽  
Algal Growth ◽  
Oxygen Depletion ◽  
Nitrogen And Phosphorus ◽  
Limiting Nutrient ◽  
Von Liebig ◽  
The Baltic ◽  
Fritz Haber

The fertilizers commonly used by gardeners have many ingredients, but the biggest two are nitrogen and phosphorus, either of which can limit plant and algal growth. The idea that only one nutrient limits growth is encapsulated by Liebig’s Law of the Minimum, named after Justus von Liebig, a 19th-century German chemist. Liebig is also called the “father of fertilizer” because of his work on formulating and promulgating commercial fertilizers. However, he wasn’t the first to discover the Law, and he was wrong about the most important ingredient of fertilizers. This chapter outlines the arguments among limnologists, oceanographers, and geochemists about whether nitrogen or phosphorus sets the rate of algal growth and thus production of the organic material that drives oxygen depletion. The chapter discusses that the limiting nutrient varies with the type of aquatic habitat. In dead zones like the Gulf of Mexico, parts of the Baltic Sea, and Chesapeake Bay, bioassay experiments have shown that nitrogen is usually limiting. The nitrogen necessary for fertilizer and ammunitions comes from the Haber-Bosch process. The chapter reviews the life of one of the two German inventors, Fritz Haber, and how it was full of contradictions if not tragedy.

scholarly journals Oxygen depletion in subarctic peatland thaw lakes

2017 ◽  
Vol 3 (2) ◽  
pp. 406-428 ◽  
Author(s):  
Bethany N. Deshpande ◽  
Frédéric Maps ◽  
Alex Matveev ◽  
Warwick F. Vincent
Keyword(s):  
Dissolved Oxygen ◽  
Ice Cover ◽  
Oxygen Depletion ◽  
Freshwater Ecosystems ◽  
In Situ Sensors ◽  
Modelling Studies ◽  
Bottom Waters ◽  
Bacterial Decomposition ◽  
Permafrost Thawing ◽  
Thaw Lakes

Permafrost thawing and erosion results in the enrichment of northern lakes by soil organic matter. These allochthonous inputs favour bacterial decomposition and may cause the draw-down of dissolved oxygen to anoxic conditions that promote methanogenesis. Our objective in the present study was to determine the seasonal variations in dissolved oxygen in a set of permafrost peatland lakes in subarctic Quebec, Canada, and to relate these changes to metabolic rates, ice cover, and mixing. The lakes had high dissolved organic carbon concentrations, and their surface waters in summer had greenhouse gas concentrations that were up to one (CO2) to three (CH4) orders of magnitude above air-equilibrium values, indicating their strongly heterotrophic character. Consistent with these observations, the peatland lakes had elevated rates of bacterial production and oxygen consumption. Continuous measurements of oxygen by in situ sensors and of ice cover by automated field cameras showed that the lakes became fully anoxic shortly after freeze-up. The waters were partially re-oxygenated by mixing events in spring and fall, but in one lake, the bottom waters remained anoxic throughout the year. These observations provide a foundation for subsequent biogeochemical and modelling studies of peatland thaw lakes as an abundant class of Arctic freshwater ecosystems.

Dynamics of a cyanobacterial bloom in a hypereutrophic, stratified weir pool

2003 ◽  
Vol 54 (1) ◽  
pp. 27 ◽  
Author(s):  
P. A. Thompson ◽  
A. M. Waite ◽  
K. McMahon
Keyword(s):  
Growth Rates ◽  
Algal Blooms ◽  
Dissolved Inorganic Carbon ◽  
Cyanobacterial Bloom ◽  
Nutrient Concentrations ◽  
P Availability ◽  
The Public ◽  
Limiting Nutrient ◽  
Bottom Waters ◽  
Oxygenated Water

In summer 1997–1998, a bloom of the cyanobacteria Anabaena circinalis (Rabenhorst) and Anabaena spiroides (Klebahn) contaminated the Canning River (Perth, WA), forcing its closure to the public for swimming and fishing. We investigated the major nutrient fluctuations before, during and after the bloom. The river was persistently temperature stratified at least 1 month prior to the bloom. The surface and bottom layers of water had distinctly different nutrient concentrations, which meant that biomass and growth rates of the phytoplankton within each layer were limited by different nutrients. At the peak of the bloom, in the bottom waters growth rates were light limited and biomass was nitrogen limited, whereas in the surface waters biomass was controlled by phosphorus (P) availability and growth rates were probably limited by the lack of dissolved inorganic carbon. Another consequence of stratification was that, at the peak of the bloom (0.25 mg chlorophyll L−1), the mostly buoyant cyanobacteria could not access 83% of the P released from sediments during the summer period of anoxia. In this situation, the injection of oxygenated water, tested as a remediation measure for algal blooms, is likely to exacerbate a bloom by providing more of the limiting nutrient to the surface layer. However, aeration prior to the bloom may reduce P release from the sediments by preventing anoxia.

Solution concentrations of nutrient ions below the rooting zone of a sugar maple stand: relations to soil moisture, temperature, and season

1993 ◽  
Vol 23 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Xiwei Yin ◽  
Neil W. Foster ◽  
Paul A. Arp
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Soil Solution ◽  
Sugar Maple ◽  
Temporal Variations ◽  
Solution Chemistry ◽  
Rooting Zone ◽  
Temperature Solution ◽  
Turkey Lakes Watershed

Temporal variations of ion concentrations in soil solution were analyzed in relation to soil percolate volume, soil water content, soil temperature, solution chemistry, and season. The study site was an uneven-aged, mature northern tolerant hardwoods dominated by sugar maple (Acersaccharum Marsh.) within the Turkey Lakes Watershed, Ontario. Six ions were investigated: nitrate (NO3−), sulfate (SO42−), calcium (Ca2+), magnesium (Mg2+), potassium (K+), and ammonium (NH4+). Nitrate concentrations in the soil solution depended on season during the nonfoliage period and responded directly to forest floor percolation, soil water content, and season during the foliage period. Variations of SO42−, Ca2+, and Mg2+ concentrations were mostly attributable to NO3− concentration, and to season to a lesser extent. Concentrations of K+ and NH4+ correlated only weakly to any of the "independent" variables included in the analysis, reflecting a high affinity between these ions and the soil colloids.

Nutrient cycling in Huntington Forest and Turkey Lakes deciduous stands: nitrogen and sulfur

1992 ◽  
Vol 22 (4) ◽  
pp. 457-464 ◽  
Author(s):  
M.J. Mitchell ◽  
N.W. Foster ◽  
J.P. Shepard ◽  
I.K. Morrison
Keyword(s):  
New York ◽  
Forest Floor ◽  
Sugar Maple ◽  
Tree Mortality ◽  
C:N Ratio ◽  
Mineral Soil ◽  
Stand Age ◽  
Adirondack Mountains ◽  
Contributing Factors ◽  
Turkey Lakes Watershed

Biogeochemical cycling of S and N was quantified at two hardwood sites (Turkey Lakes watershed (TLW) and Huntington Forest (HF)) that have sugar maple (Acersaccharum Marsh.) as the major overstory component and are underlain by Spodosols (Podzols). TLW and HF are located in central Ontario (Canada) and the Adirondack Mountains of New York (U.S.A), respectively. Major differences between the TLW and HF sites included stand age (300 and 100 years for TLW and HF, respectively), age of dominant trees (150–300 and 100 years for TLW and HF, respectively), and the presence of American beech (Fagusgrandifolia Ehrh.) at HF as well as lower inputs of SO42− and NO3− (differences of 99 and 31 mol ion charge (molc)•ha−1•year−1, respectively) at TLW. There was an increase in concentration of SO42− and NO3− after passage through the canopy at both sites. A major difference in the anion chemistry of the soil solution between the sites was the much greater leaching of NO3− at TLW compared with HF (1300 versus 18 molc•ha−1•year−1, respectively). At HF, but not TLW, there was a marked increase in SO42− flux (217 molc•ha−1•year−1) when water leached from the forest floor through the mineral soil. The mineral soil was the largest pool (>80%) of N and S for both sites. The mineral soil of TLW had a C:N ratio of 16:1, which is much narrower than the 34:1 ratio at HF. This former ratio should favor accumulation of NH44+ and NO3− and subsequent NO3− leaching. Laboratory measurements suggest that the forest floor of TLW may have higher N mineralization rates than HF. Fluxes of N and S within the vegetation were generally similar at both sites, except that net requirement of N at TLW was substantially lower (difference of 9.4 kg N•ha−1•year−1). The higher NO3− leaching from TLW compared with HF may be attributed mostly to stand maturity coupled with tree mortality, but the absence of slow decomposing beech leaf litter and lower C:N ratio in the soil of the former site may also be contributing factors.

scholarly journals Psychiatry in free fall: In pursuit of a semiotic foothold

2003 ◽  
Vol 31 (2) ◽  
pp. 533-546
Author(s):  
Stepan Davtian ◽  
Tatyana Chernigovskaya
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Free Fall ◽  
Distinctive Features ◽  
The World ◽  
Key Factor ◽  
A Chain ◽  
A Site ◽  
Purposeful Activity ◽  
Three Dimensional Space

Diagnostics of a mental disorder completely bases on an estimation of patient’s behaviour, verbal behaviour being the most important. The behaviour, in turn, is ruled by a situation expressed as a system of signs. Perception of a situation could be seen as a function, which depends on the context resulting from the previous situations, structuring personal world. So the world is not given — it is being formed while the person is in action. We argue that distinctive features of behaviour, including its abnormal variants, can be explained not in categories of characters and diseases but in terms of situations taking place in individual worlds. The situation in which a person perceives himself is not simply a site in a three-dimensional space at a certain moment, but a part of the world and an episode of his life. Like a text composed of words, individual world is composed of situations. Each of them needs certain context to cope with ambiguity. This context is induced by the world as a whole. And the world, in turn, is presented as a chain of situations. If the context cannot help to interpret a situation adequately, uncertainty can be eliminated by actions clarifying a situation, which is changed in a predictable way. Thus, purposeful activity, skills to make predictions and corrections of one’s own actions are crucial. Weakness of any of them inevitably leads to the distortion of the presentation of the world, to wrong evaluation of situations and, as a result, to inadequate actions that finally reduce the activity as being ineffective. Thus, the lack of activity becomes the key factor in the development of disorder, being simultaneously its cause and effect. In periods of insufficient activity conditions for violated (and violating) sign processing arise. Possible variants of sign malfunction are: oligosemia (reduction of the number of perceivable signs), hyposemia (decrease of significance of signs), hypersemia (increase of significance of some signs at the expense of others), ambisemia (uncertainty of sign, when situation remains unclear), cryptosemia (recognition of signs not obvious for other observers), and parasemia (perverted interpretation of signs influenced by a false context).

scholarly journals Thallium isotopes reveal protracted anoxia during the Toarcian (Early Jurassic) associated with volcanism, carbon burial, and mass extinction

2018 ◽  
Vol 115 (26) ◽  
pp. 6596-6601 ◽  
Author(s):  
Theodore R. Them ◽  
Benjamin C. Gill ◽  
Andrew H. Caruthers ◽  
Angela M. Gerhardt ◽  
Darren R. Gröcke ◽  
...  
Keyword(s):  
Mass Extinction ◽  
Biological Evolution ◽  
Oxygen Depletion ◽  
Early Jurassic ◽  
Large Igneous Province ◽  
Mass Extinctions ◽  
Oceanic Anoxic Event ◽  
Carbon Burial ◽  
Anoxic Basins ◽  
Bottom Waters

For this study, we generated thallium (Tl) isotope records from two anoxic basins to track the earliest changes in global bottom water oxygen contents over the Toarcian Oceanic Anoxic Event (T-OAE; ∼183 Ma) of the Early Jurassic. The T-OAE, like other Mesozoic OAEs, has been interpreted as an expansion of marine oxygen depletion based on indirect methods such as organic-rich facies, carbon isotope excursions, and biological turnover. Our Tl isotope data, however, reveal explicit evidence for earlier global marine deoxygenation of ocean water, some 600 ka before the classically defined T-OAE. This antecedent deoxygenation occurs at the Pliensbachian/Toarcian boundary and is coeval with the onset of initial large igneous province (LIP) volcanism and the initiation of a marine mass extinction. Thallium isotopes are also perturbed during the T-OAE interval, as defined by carbon isotopes, reflecting a second deoxygenation event that coincides with the acme of elevated marine mass extinctions and the main phase of LIP volcanism. This suggests that the duration of widespread anoxic bottom waters was at least 1 million years in duration and spanned early to middle Toarcian time. Thus, the Tl data reveal a more nuanced record of marine oxygen depletion and its links to biological change during a period of climatic warming in Earth’s past and highlight the role of oxygen depletion on past biological evolution.

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