Chemical Limnology Research Articles

Physical and chemical limnology of 34 ultra-oligotrophic lakes and ponds near Wynniatt Bay, Victoria Island, Arctic Canada

Thirty-four lakes and ponds on north-central Victoria Island (Arctic Canada) were examined in order to characterize the limnological conditions of these unstudied aquatic ecosystems, and to provide baseline data as part of a larger study monitoring future changes in climatically-sensitive high-latitude locations. Similar to several other arctic regions, the lakes and ponds were slightly alkaline (mean pH = 7.65), dilute (mean specific conductance = 96.4 μS), and low in nutrients. What distinguished this limnological data set was the ultra-oligotrophic nature of the lakes and ponds, as mean phosphorus (1.3 μg l−1) and chlorophyll a (0.4 μg l−1) concentrations were amongst the lowest recorded in arctic environments. Also, dissolved organic carbon (DOC) concentrations (often <1 mg l−1) were 2–3 times lower than those recorded for ponds at similar latitudes. Principal components analysis (PCA) separated sites primarily along a gradient of DOC and specific conductance, and along a secondary gradient of particulate nitrogen, likely reflecting differences in phyto- and zooplankton biomass. These ultra-oligotrophic lakes and ponds should show a marked response to global warming. As DOC acts as a natural UV radiation screen, the combination of ultra-oligotrophic conditions and low DOC levels suggests that the biota within these sites are representative of those adapted to living in highly stressful environments. Lakes and ponds in this region make ideal monitoring sites, as they should be especially responsive to future environmental changes.

Limnology and biology of saline lakes in the Rauer Islands, eastern Antarctica

The Rauer Islands contain more than fifty shallow lakes and small ephemeral ponds. Despite their proximity to the Vestfold Hills - one of the most diverse and intensively studied lake districts of eastern Antarctica - the lakes of the Rauer Islands have remained undescribed. In this study the physical and chemical limnology and biology of ten lakes is presented and their species-environment relationships explored using multivariate statistics. Analyses of chemical and biological data indicate that the Rauer Islands form a distinct limnological province amongst the lakes of the Prydz Bay oases. Salinities range from hypo- to hyper-saline with an ionic order close to that of seawater. Deviance from this order indicates either an earlier origin for some of the most hypersaline lakes when compared with the Vestfold Hills, more rapid evaporation vs precipitation or differences in the sources of ions resulting from isostatic history. With fluctuating salinities, winter water temperatures below –10°C, seasonal ice and slush formation, desiccation and high levels of solar radiation, the lacustrine environment presents considerable abiotic challenges for biological survival. Results indicate that there is little or no planktonic flora in the lakes and no zooplankton were encountered. Despite this, analyses of pigments, diatoms and other micro-algae revealed an active and diverse benthic biota characterized by filamentous cyanobacteria with interstitial algae. Thirty-eight diatom taxa, and a selection of Chlorophyta and Xanthophyta were detected amongst the cyanobacteria. Clusters in the diatom data correspond to salinity. Further analyses of the relationships between the biota and their environment revealed some of the strategies employed for survival. In particular, the synthesis of scytonemin was detected. This pigment is known to function as an extracellular UV sunscreen which protects cyanobacterial cells against damage by ultraviolet radiation. These results support the hypothesis that environmental extremes and biogeographical isolation control the biology of these lakes.

Physical and chemical limnology of 204 lakes from the Canadian Arctic Archipelago

The physical and chemical limnology of 204 lakes from across the Canadian Arctic Archipelago was examined. Mean summer air temperature did not correlate well with lake chlorophyll levels due to the predominance of ultra-oligotrophic hard-water lakes located in a polar climate. Local geology influences ion budgets and is an important factor in determining pelagic phosphorus availability, carbon cycling and metal concentrations. Ratios of particulate carbon, particulate nitrogen and chlorophyll a indicate that planktonic microorganisms are not always the major producers of organic carbon in arctic lakes. Allochthonous particulate matter contributes significantly to the carbon and phosphorus budgets of small and mid-sized lakes across the Arctic, although the availability of these elements is controlled by many interacting geochemical and biological factors. Phosphorus is generally limiting, however, increases in available phosphorus, nitrogen and carbon are all required to make significant long-term differences in lake productivity. Particulate phosphorus levels can be high in lakes where phosphorus-rich shales or carbonatite bedrock are present. These phosphorus-enriched lakes are found in several areas across the mid-arctic islands, however, only small amounts of this nutrient are available as soluble reactive phosphorus. Although lakes throughout the Arctic are typically ultra-oligotrophic, they still represent an important sink for allochthonous nutrient deposition.

Causes and effects of long periods of ice cover on a remote high Alpine lake

The response of the physical and chemical limnology of Hagelseewli (2339 m a.s.l.) to local meteorological forcing was investigated from 1996 to 1998 using an automatic weather station, thermistor chains, water samples and sediment traps. On-site meteorological measurements revealed the paramount importance of local topographic shading for the limnology of the lake. A high cliff to the south diminishes incident radiation by 15% to 90%, resulting in a long period of ice cover. Hence, the spring and summer seasons are extremely condensed, allowing only about 2 months per year for mixing, oxygen uptake, nutrient inflow, water exchange and phytoplankton growth. Regular measurements of water temperature, chemistry and diatom composition show that Hagelseewli responds very rapidly to changes in nutrient concentrations and light conditions. This response is restricted mainly to an extremely short productivity pulse, which takes place as soon as the lake is completely free of ice. Ice-free conditions are indicated by the occurrence of planktonic diatoms. In contrast to most low-altitude lakes, maximum productivity occurs in the middle of the water column (6-9 m), where first light, and then soluble reactive phosphorus (SRP), are the limiting factors. During the period of thawing, large amounts of ammonium enter the lake. Nevertheless, allochthonous nutrient input is not important because SRP, the limiting nutrient for algal growth, originates from the sediments. Water chemistry data and data from sediment traps show that, although autochthonous calcite precipitation does occur, the calcite crystals are redissolved completely in the bottom waters during the extended period of ice cover. Thus, the most important factor for changes in the nutrient budget, primary production and preservation of calcite is the bottom water oxygen status, which is governed by the occurrence of an ice-free period. We hypothesise that the duration of the ice-free period is of minor importance for the generation of particles that might be archived in the sedimentary rec??ord as proxy climate indicators. Such particles are produced mainly during times of peak primary production, which last only for a few days before production decreases again to very low levels. Therefore, with respect to the type of climatic signal that might be recorded in Hagelseewli, we presume that what is most likely to be archived in the sedimentary record is the mere occurrence, rather than the duration of the ice-free period.

Zooplankton community composition of lakes in the Yukon and Northwest Territories (Canada) : relationship to physical and chemical limnology

We analysed associations between zooplankton species composition and local abiotic factors in 30 lakes located along a 900 km south-north transect from Whitehorse (Yukon Territory) to Inuvik (Northwest Territories). The lakes were situated in three broadly defined vegetation zones: (i) Boreal forest (between Whitehorse and Dawson City), (ii) alpine tundra (Ogilvie mountains north of Dawson City) and (iii) subarctic forest-tundra (near Inuvik). Lakes in the alpine tundra were characterised by lower conductivity, temperature, chlorophyll a and nutrients than those in the other two zones. Those in the forest-tundra were generally small and shallow, and had higher chlorophyll a concentrations than lakes further south. Lakes in forested catchments spanned a larger latitudinal range and exhibited a greater variety of physical and chemical characteristics. However, they were generally deeper, with higher conductivity, temperature and ionic concentrations. Forty-one zooplankton taxa were identified from the 30 lakes, of which the most frequently occurring were the rotifers Conochilus unicornis, Kellicottia longispina, Keratella cochlearis and Polyarthra vulgaris, the cladocerans Daphnia middendorffiana and Bosmina longirostris, and the copepods Leptodiaptomus pribilofensis, Heterocope septentrionalis and Cyclops spp. The lakes contained between two and fifteen species (mean = 6.9). Alpine tundra lakes contained slightly less species (mean = 5.8) than those at lower elevations; in particular the cladoceran fauna was depauperate or absent. Relationships among the lakes, species and environmental factors were examined using canonical correspondence analysis, with forward selection and associated Monte Carlo permutation tests. Chloride, silica and temperature showed statistically significant relationships with species distribution, and together these abiotic factors explained 25% of the variation in zooplankton communities within Yukon and Northwest Territories lakes.

Physical and chemical limnology of northern boreal lakes, Wood Buffalo National Park, northern Alberta and the Northwest Territories, Canada

Physical and chemical variables were measured in 35 lakes from Wood Buffalo National Park, northern Alberta and the Northwest Territories, Canada. Of these lakes, 22 were sinkholes, situated on limestone and gypsum, five were situated on the Canadian Shield and eight were shallow 'muskeg' lakes located on calcareous shales. All of the lakes were small to moderate in size. For each of the 35 lakes, 37 environmental variables were measured. Principal component analysis (PCA) revealed that underlying geology strongly influenced limnic properties. Shield lakes were characterized by higher concentrations of A1 and Fe, and lower pH values, specific conductivities and concentrations of ions such as, Ca, SO4, Li, Mg and Na, than either the sinkhole or the muskeg lakes. The muskeg lakes were differentiated from the sinkhole lakes by decreased Secchi depth owing to higher concentrations of dissolved organic carbon (DOC) and greater productivity, as evidenced by high concentrations of particulate organic carbon (POC) and chlorophyll a. Nitrogen (NH3 and NO2) was also notably higher at these sites.

Physical and chemical limnology of 59 lakes located between the southern Yukon and the Tuktoyaktuk Peninsula, Northwest Territories (Canada)

Des donnees sur les caracteristiques limnologiques et chimiques obtenues pour 59 lacs dans le Yukon et la partie adjacente des Territoires du Nord-Ouest (Canada) ont ete interpretees a l'aide de l'analyse de regression lineaire et de l'analyse des composantes principales. Les sites d'etude sont des lacs qui representent une grande variete de regions ecoclimatiques, echelonnees sur de longs gradients de latitude (60°37'-69°35'N) et d'altitude (15 a 1387 m au-dessus du niveau de la mer). Les echantillons d'eau preleves dans chacun des lacs ont ete analyses pour determiner la concentration des ions traces, des metaux traces, des elements nutritifs et de la chlorophylle a. La plupart des lacs etaient pauvres en solutes (conductivite moyenne de 160 μS.cm -1 ) et leur pH variait de legerement acide a alcalin (etendue de pH = 5,9 a 9,3). La composition ionique a varie de Ca-Cl-Na pres de l'ocean Arctique a Ca-HCO 3 vers l'interieur des terres, ce qui reflete des differences dans les bassins hydrographiques locaux et la proximite de la mer. De maniere generale, les sites arctiques et alpins ont presente de nombreuses similitudes, mais des differences considerables en ce qui a trait a la chimie de l'eau ont ete observees entre les sites situes a l'interieur du Territoire du Yukon. Ces differences peuvent etre liees aux differences touchant les caracteristiques du substrat rocheux et de la vegetation du bassin versant.

Physical and chemical limnology of 24 lakes located between Yellowknife and Contwoyto Lake, Northwest Territories (Canada)

Data on the water chemistry and limnology of 24 lakes located between Yellowknife (62 8279N, 1148219W) and Contwoyto Lake (658309N, 1108009W) in the central Northwest Territories were examined using principal components analysis and other statistical techniques. The study sites were mostly shallow ( Zmax = 2.5-25 m; mean = 8.2 m), nutrient-poor (3.4- 12.7 mg total phosphorus/L; mean = 6.6 mg · L -1 ), low-alkalinity lakes. Water was typically low in solutes (specific conductance near 0-100 mS · cm -1 ), with slightly acidic to alkaline pH (6.2-8.9). Levels of all nutrients and major ions showed identical trends of decreasing concentrations with increasing latitude, with the highest concentrations generally in lakes with conifer-forested catchments in the south. Resume : Les donnees sur les caracteristiques chimiques et limnologiques de 24 lacs situes entre Yellowknife (62 8279N, 1148219W) et le lac Contwoyto (658309N, 1108009W) dans le centre des Territoires du Nord-Ouest (T.N.-O.) ont ete examinees a l'aide de l'analyse des composantes principales. Les sites d'etude etaient pour la plupart des lacs peu profonds ( Zmax = 2,5 a 25 m; moyenne = 8,2 m), pauvres en elements nutritifs (3,4 a 12,7 mg · L -1 en phosphore totale, moyenne = 6,6 mg · L -1 ) et de faible alcalinite. De maniere typique, l'eau etait pauvre en solutes (conductivite electrique pres de 0 a 100 mS · cm -1 ), et son pH variait de legerement acide a alcalin (6,2 a 8,9). Les concentrations de tous les elements nutritifs et des ions majeurs ont montre des tendances identiques, c.-a-d. qu'ils diminuaient avec l'augmentation de la latitude, les concentrations les plus elevees se trouvant generalement dans les lacs meridionaux avec forets de coniferes dans le bassin versant. (Traduit par la Redaction)

Physical and chemical limnology of 24 lakes located between Yellowknife and Contwoyto Lake, Northwest Territories (Canada)

Physical and chemical limnology of 24 lakes located between Yellowknife and Contwoyto Lake, Northwest Territories (Canada)

Physical and chemical limnology of 59 lakes located between the southern Yukon and the Tuktoyaktuk Peninsula, Northwest Territories (Canada)

Physical and chemical limnology of 59 lakes located between the southern Yukon and the Tuktoyaktuk Peninsula, Northwest Territories (Canada)

Using Field and Laboratory Exercises on Local Water Bodies to Teach Fundamental Concepts in an Introductory Oceanography Course

Our introductory oceanography course is designed to introduce students to the interdisciplinary field of oceanography by supplementing traditional classroom offerings with extensive hands-on field and laboratory exercises based primarily on nearby Lake Winnebago. Six weeks of our ten-week fall term are devoted to boat-based field and laboratory exercises, including two weeks on sediments and sedimentary processes, three weeks on chemical and physical limnology and oceanography, and one week on aquatic ecology. These investigative, research-based exercises have improved the learning experience for students by engaging them in the process of solving local geologic problems using data which they have collected themselves. The process of conducting the data collection and analysis, discussing interpretations with peers, and writing a detailed report improves students' comprehension of scientific concepts and provides them with a familiar reference with which to compare concepts presented in lectures or readin...

Limnology at the National Science Foundation

In the past several years, a number of people have inquired and expressed concern regarding the support for limnological research at the National Science Foundation. There is a perception among some members of the scientific community that the discipline of limnology, the study of inland waters, has not been well‐served at NSF. Communications from a variety of sources suggest that many limnologists perceive a problem with the status of the discipline and with the leadership being shown by the federal government in this area. Consistently mentioned issues include the fate of proposals involving biogeochemistry and the lack of a “home within the NSF” for the subdisciplines of physical and chemical limnology.

Aspects of the limnology of Yeppen Yeppen Lagoon, central Queensland

Aspects of the morphometry and physical and chemical limnology of Yeppen Yeppen Lagoon, in tropical Australia, have been investigated. The lagoon is a channel billabong lying in the old bed of the Fitzroy River. It has a relatively small, shallow and elongated basin. Seasonal variations in water temperature, light regime, oxygen concentration, pH and conductivity suggest that the lagoon exhibits a warm monomictic pattern of thermal stratification rather than a continuous warm polymictic one. The annual heat budget was 3294 calories cm-2 year-1. Maximum work of the wind was 238.8 g-cm cm-2, and maximum stability was 34.5 g-cm cm-2. Despite the apparently low stability of stratification, the lagoon remained thermally stratified for much of the year. Analysis of wind-distributed heat suggested that slow mixing was taking place even during periods of relatively high stability, although this mixing was insufficient to reoxygenate the hypolimnion, which remained anoxic for much of the year. Yeppen Yeppen Lagoon is likely to prove eutrophic, and it is suggested that primary productivity will be high because a large volume of the lagoon's water is well lit and a large sediment surface area is in contact with the epilimnion. Notes on the biota of Yeppen Yeppen Lagoon are also given.

Chemical limnology of a hypertrophic gravel-pit lake

Some features of the chemical limnology of a hypertrophic, gravel-pit lake close to Madrid (Spain) have been studied at weekly intervals throughout a year. El Porcal Lake in an alkaline, slightly saline, water body without surface inflow or outflow. Anoxia is a common feature below the 2 m level from May to September. Dissolved oxygen oversaturation and pH above 9,00 occurred frequently in surface waters throughout the study period. Alkalinity totalled to 2,5-3,5 meq.l-1 , bicarbonate being the main inorganic carbon fraction. Inorganic carbon is a key parameter in the chemistry of the lake, as indicated by statistical correlations. Nitrate and nitrite values were very high, probably as a result of high nitrification rates. Ammonia levels were lower than those of nitrite and nitrate. Soluble Reactive Phosphorus ranged over three orders of magnitude, sometimes occurring below detection limits. No plankton collapses have been observed but frequent oscillations in the chemical parameters have been the rule during the whole year. Groundwater seepage might be a very important source of nutrients. Most of the chemical features showed time lags of a week in autocorrelation functions, suggesting an unknown control mechanism for the temporal dynamics of the chemical limnology of El Porcal Lake.

Conditional stability constants and binding capacities for copper (II) by ultrafilterable material isolated from six surface waters of Wyoming, USA

Ultrafilterable material < 0.15 µm was collected from six Wyoming surface waters, for which the chemical limnology had also been determined. The material was separated into four nominal size-fractions and the binding capacity of each for copper was determined by a hyperbolic, site-saturation model. The conditional, overall, thermodynamic stability constants (K′) for binding of copper were determined by two discrete models: The one- and two-component Scatchard functions, and two continuous multiligand models; The one- and three-component Gaussian Scatchard functions. The accuracy of the stability constants to predict the speciation of Cu(II) in the titration of the isolated fractions and of whole waters was evaluated by comparing the predictions of the thermodynamic, geochemical simulation model, GEOCHEM to those measured by selective ion electrode. The Cu-binding capacity of material retained by ultrafilters was positively correlated with the hardness and alkalinity of the surface waters, from which they were isolated as well as the percent ash content of the ultrafilter-retained material. The magnitude of the conditional stability constant (Kinfisup′) decreased as the ratio of the total Cu concentration to total concentration of Cu-binding sites increased. The cumulative frequency distribution of Kinfisup′was log-normally distributed. All four of the models used to estimate the conditional stability constants gave reasonable prediction of the speciation of Cu for both fractionated and whole waters but, depending on the situation, the one- or two-component Scatchard estimate generally gave the best predictions of the proportion of copper, which would be expected to be bound.

Chemical limnology of Georgian Bay and the North Channel between 1974 and 1980

Chemical limnology of Georgian Bay and the North Channel between 1974 and 1980

Chemical limnology of soft water lakes in the Upper Midwest

Water samples from 36 lakes in northern Minnesota, Wisconsin, and Michigan were collected and analyzed during 1983–1984. All study lakes were dilute and had total alkalinities of less than 150 μeq · L−1. Minnesota lakes have hydrologic inputs from the watershed and inputs of base cations derived from the watershed. Study lakes in Minnesota had higher total alkalinities, dissolved organic carbon, and noncarbonate alkalinity as a result of watershed inputs. Lakes in Michigan and Wisconsin were precipitation-dominated seepage lakes that have lower concentrations of base cations than lakes in Minnesota. All of the study lakes have lower sulfate concentrations than expected, based on atmospheric wet deposition and evapotranspiration.

Effects of seasonal water level changes on the chemical and biological limnology of Lake Murray, Papua New Guinea

Lake Murray, with a surface area of 647 km2 and a high-water convoluted shoreline 2038 km long, is the largest lake in Papua New Guinea and exhibits marked seasonal fluctuations in water level. The fall in water level of 4 m between April and December 1982 was accompanied by a marked rise in pH (from 5.3 to 9.6), conductivity (from 12 to 100 �S cm-1), total hardness (from 80 to 400�M) and filterable residue (from 11 to 45 mg l-1). In November 1982, maximum production of phyto-planktonic oxygen was 1120 mg O2 m-3 h-1 at the surface but declined sharply with depth because of light attenuation by suspended solids. It was much higher than that recorded in April 1982 (250 mg O2 m-3 h-1). The long shoreline and the shallowness of the lake result in a very large littoral zone. Diurnal variation in oxygen concentrations during periods of high water level indicated that the littoral zone is a very productive area of the lake. However, when the water level is low, the lake is surrounded by a wide expanse of barren mud.

Chemical limnology of two artificial lakes used for both stormwater management and recreation

The aims of this study were to document the mainly chemical behaviour of two linked artificial lakes used for both stormwater management and recreation in the new town of Craigavon. Further, the understanding of their behaviour should help in their management and the design of other similar lakes.

Precipitation Chemistry and Chemical Limnology of Fertilized and Natural Lakes at Saqvaqjuac, N.W.T.

Precipitation at Saqvaqjuac (northwest coast of Hudson Bay, 60°39′N) had high concentrations of sea salts, was moderately acidic, and had less SO4 and total N than lower latitude precipitation, although SO4 sources were distant. Watershed retention was high for H+, but negative for other elements as a consequence of isostatic rebound. Annual element runoff was a function of the timing of melt runoff and summer rain events because of permafrost. Lake retention of Si was higher than P because of the different times of loading, late summer versus spring. Conservative element mass did not change overwinter except in low-elevation Spring Lake, where residual Cl, Na, and K diffused from the sediments. Phosphorus and N were the only elements incorporated into black ice. As a result of freezeout and incomplete meltwater mixing beneath lake ice, element concentrations were 1.6 times higher in lakes than inflows, and major ion turnover times were 1.5–2.0 times higher than water turnover times.