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1
Bergmann, Martin A. y Harold E. Welch. "Spring Meltwater Mixing in Small Arctic Lakes". Canadian Journal of Fisheries and Aquatic Sciences 42, n.º 11 (1 de noviembre de 1985): 1789–98. http://dx.doi.org/10.1139/f85-224.
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Meltwater mixing in small arctic lakes at Saqvaqjuac (63°68′N, 90°40′W) was studied in 1980 and 1981 to evaluate the applicability of theoretical lake water renewal times to the modeling of ice-covered lakes. Two 370-GBq tritium additions were made to 7.09-ha P&N Lake. One was mixed with the unfrozen water at the time of maximum lake-ice thickness (May 1980) and the other was mixed with the lake immediately after freezing (October 1980). Dye experiments were also performed at four lakes to define the spatial and temporal distribution of the inflow and icemelt layers. Results from the tritiated water and dye addition experiments, as well as conductance and temperature profiles, showed that during ice-on, the cold low-density meltwater floated in a thin layer 0–100 cm beneath the ice, extended over the entire subice-surface area, and left the lake without mixing with the heavier subice water. These results imply that (1) lake models incorporating a lake flushing rate term need to be reevaluated to accommodate the lack of meltwater mixing beneath spring ice and (2) more attention should be given to the early spring meltwater chemistry and its distribution within the upper lake strata.
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Houser, Jeffrey N. "Water color affects the stratification, surface temperature, heat content, and mean epilimnetic irradiance of small lakes". Canadian Journal of Fisheries and Aquatic Sciences 63, n.º 11 (1 de noviembre de 2006): 2447–55. http://dx.doi.org/10.1139/f06-131.
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The effects of water color on lake stratification, mean epilimnetic irradiance, and lake temperature dynamics were examined in small, north-temperate lakes that differed widely in water color (1.5–19.8 m–1). Among these lakes, colored lakes differed from clear lakes in the following ways: (i) the epilimnia were shallower and colder, and mean epilimnetic irradiance was reduced; (ii) the diel temperature cycles were more pronounced; (iii) whole-lake heat accumulation during stratification was reduced. The depth of the epilimnion ranged from 2.5 m in the clearest lake to 0.75 m in the most colored lake, and 91% of the variation in epilimnetic depth was explained by water color. Summer mean morning epilimnetic temperature was ~2 °C cooler in the most colored lake compared with the clearest lake. In clear lakes, the diel temperature range (1.4 ± 0.7 °C) was significantly (p = 0.01) less than that in the most colored lake (2.1 ± 1.0 °C). Change in whole-lake heat content was negatively correlated with water color. Increasing water color decreased light penetration more than thermocline depth, leading to reduced mean epilimnetic irradiance in the colored lakes. Thus, in these small lakes, water color significantly affected temperature, thermocline depth, and light climate.
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Sellers, Todd J., Brian R. Parker, David W. Schindler y William M. Tonn. "Pelagic distribution of lake trout (Salvelinus namaycush) in small Canadian Shield lakes with respect to temperature, dissolved oxygen, and light". Canadian Journal of Fisheries and Aquatic Sciences 55, n.º 1 (1 de enero de 1998): 170–79. http://dx.doi.org/10.1139/f97-232.
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The distribution of lake trout (Salvelinus namaycush) with respect to water temperature, dissolved oxygen, and light intensity was surveyed in three small Canadian Shield lakes at the Experimental Lakes Area, northwestern Ontario. Based on hydroacoustic and gillnet surveys, there was considerable variation among lakes in temperatures occupied by lake trout during the summer. During the day, lake trout were concentrated at 4-8°C in Lake 375, broadly distributed from 6 to 15°C in Lake 442, and concentrated in the epilimnion at 19°C in Lake 468. At night, lake trout in all lakes occupied epilimnetic waters at 19-20°C. Lake trout inhabited highly oxygenated water, with 75-90% of fish at >6 mg dissolved oxygen ·L-1 throughout the spring and summer in all three lakes. Light intensity did not affect lake trout distribution in Lake 468 but may have contributed to lake trout daytime descent into cool waters in Lakes 375 and 442. We suggest that previously assumed niche boundaries of lake trout do not adequately describe critical habitat for the species in small lakes, the same lakes that are likely most sensitive to erosion of such habitat.
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Patalas, K. y A. Salki. "Spatial Variation of Crustacean Plankton in Lakes of Different Size". Canadian Journal of Fisheries and Aquatic Sciences 50, n.º 12 (1 de diciembre de 1993): 2626–40. http://dx.doi.org/10.1139/f93-286.
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The patterns of spatial distribution of planktonic crustaceans changed with increasing lake size. Greatest abundances were often found offshore in smaller lakes but nearshore in larger lakes. Interstation similarity of plankton, measured with Jaccard's and Renkonen's indices, was higher in small- to middle-sized lakes and lower in very small and very large lakes, indicating that mechanisms existed at both ends of the size spectrum which prevented plankton from mixing horizontally. The information content of a single central lake sample was evaluated against a lake average from 9–10 stations. To capture at least 80% of the species present, one station was sufficient only in smaller lakes, three to six stations were needed in the smallest and medium-sized lakes, and more than nine stations were needed in the largest lake. The single central station in small- and medium-sized lakes represented average total plankton abundance and dominant species relatively well but underestimated rare species. In larger lakes, lake average plankton was not well characterized by a single station. In Lake Superior, the central station reflected the offshore but not the nearshore community. Neither plankton abundance nor the number of species appeared related to lake size in the series of lakes investigated.
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Fulthorpe, Roberta R. y J. E. Paloheimo. "Hypolimnetic Oxygen Consumption in Small Lakes". Canadian Journal of Fisheries and Aquatic Sciences 42, n.º 9 (1 de septiembre de 1985): 1493–500. http://dx.doi.org/10.1139/f85-187.
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The hypolimnetic oxygen consumption rates of 28 Ontario lakes were calculated and compared with lake morphology, chemical concentrations, and productivity measures. In most cases, hypolimnia had upper zones where average light intensities were greater than 1% of surface light. In these layers, oxygen dynamics were highly variable from year to year and production rather than consumption was common. The ratio of areal oxygen consumption below the 1% light level to planktonic production corrected for retention was studied as a measure of percent available material decomposed. Using stepwise multiple regressions, we found this parameter to be related to mean thickness of the hypolimnion, lake organic carbon, and iron concentrations. The range of lake productivities in the data set was small and did not explain a significant portion of the variance in areal hypolimnetic depletion rates.
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Kolpakova, E. S. y A. V. Velyamidova. "Organochlorine compounds in subarctic small lakes". Arctic and Antarctic Research 66, n.º 2 (10 de julio de 2020): 180–97. http://dx.doi.org/10.30758/0555-2648-2020-66-2-180-197.
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The article presents the results of studies of the environmental properties of organochlorines which differ in properties and origin, in the lake ecosystems of the Bolshezemelskaya tundra (Nenets Autonomous Okrug, Russia). The purpose of this study was to evaluate and assess the levels, distribution characteristics and composition of organochlorines in the bottom sediments of small lakes located in the Adzva river basin in Pymvashor natural boundary (the northernmost location of the exit of thermal-mineral springs of the continental Europe) and in the adjacent area, outside this unique subarctic hydrothermal zone.In order to meet this goal, multi-method (hydrochemical, geochemical, etc.) research was carried out using standard generally approved laboratory practices with their adaptation to the study goals. The quantitative content and composition of the target individual organochlorines were determined by gas chromatographic method with electron-capture detection.The presence of chlorophenol compounds and polychlorinated benzenes (including persistent organic pollutants) was shown in the lakes sediments. The influence of specific microclimatic conditions of subarctic hydrothermal system on the composition and distribution of chlorophenol compounds in lake sediments was considered. In the small lake sediment core in Pymvashor natural boundary a reducing trend in the levels of organochlorines with depth has been recorded (conditioned among other things by the lithological features of bottom sediments). The chlorophenol compounds were found at highest concentrations (619.3–765.5 ng/g) in the sediment upper layers, rich in organic matter; chlorophenol composition was represented mainly by chlorinated phenols, most likely of biotic origin. A lower concentration (185.0 ng/g) of chlorophenol compounds of predominantly abiogenic origin was determined in the lake sediments outside hydrothermal system. The presence and levels of persistent organochlorine pollutants (pentachlorophenol 0.1–2.4 ng/g; hexa- and pentachlorobenzenes 0.4–3.6 ng/g) in the lake sediments were associated with long-range atmospheric transport from various origin sources in nearby regions and low-latitude territories.
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Squires, Margaret M., David Mazzucchi y Kevin J. Devito. "Carbon burial and infill rates in small Western Boreal lakes: physical factors affecting carbon storage". Canadian Journal of Fisheries and Aquatic Sciences 63, n.º 4 (1 de abril de 2006): 711–20. http://dx.doi.org/10.1139/f05-252.
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Effects of depression depth (ZT), lake surface elevation (ES), catchment area:lake surface area (AT:AO), trophic status, and surficial geology on sediment burial rates in small Western Boreal Plain lakes were assessed using content and chronology of cores from a relatively large and small lake on each of moraine (M), glaciofluvial (GF), and glaciolacustrine (GL) deposits. Aquatic and terrestrial plant and sediment carbon:nitrogen (C:N) suggested most buried C was aquatic. The rate of long-term total C burial averaged 31 g·m2·year1 (range: 084 g·m2·year1); this was recently 79 g·m2·year1 (range: 40180 g·m2·year1) (higher and more variable rates than previously reported for Boreal lakes). Long-term C accrual rate and sediment depth increased with increasing ZT. In each landform, a relatively low base elevation (EB = ES ZT) lake began accumulating sediment thousands of years before a high EB lake. GF depressions were deeper and had accrued more C·m2 (and infilled) faster than M and GL lakes; a large GF lake had no organic sediment, perhaps because of large groundwater inputs. Increasing AT:AO corresponded with increasing C accrual rates where precipitation and evaporation dominated (surface runoff infrequent) (M and GL) but not where groundwater dominated (GF lakes) lake water budgets, illustrating the importance of landform and depression characteristics in regionalizing lake-C burial estimates.
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MASHKOVA, IRINA V., TATYANA G. KRUPNOVA, ANASTASIYA M. KOSTRYUKOVA y NIKITA E. VLASOV. "Short Communication: Distribution of dragonflies (Odonata: Insecta) in South Ural lakes, Russia". Biodiversitas Journal of Biological Diversity 19, n.º 1 (1 de enero de 2018): 202–7. http://dx.doi.org/10.13057/biodiv/d190127.
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Mashkova IV, Krupnova TG, Kostryukova AM, Vlasov NE. 2018. Short Communication: Distribution of dragonflies (Odonata: Insecta) in South Ural lakes, Russia. Biodiversitas 19: 202-207. This paper studies the diversity and distribution of Odonata (Insecta) in the South Urals region lakes such as Lake Large Miassovo, Lake Small Miassovo, Lake Ilmenskoe, Lake Savelkul and Lake Baraus. We revised dragonflies in five lakes during May-September 2014-2016. Dragonflies and larvae were identified up to the species. As results, 36 species (12 Zygoptera and 22 Anisoptera) belonging to 15 genera were recorded. To compare the similarities of dragonfly communities of different lakes we used the Canonical Correspondence Analysis (CCA) according the Jaccard index. Comparing the number of records of odonate species for selected lakes in our study, we found that the small richness of species was typical for lakes Savelkul and Baraus (22% and 25% of the total number of species, respectively) and the large values of the species richness was obtained for lakes Small Miassovo, Ilmenskoe and Large Miassovo (50%, 72%% and 80% of the total number of species, respectively).
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Little, Sarina, Tamlin M. Pavelsky, Faisal Hossain, Sheikh Ghafoor, Grant M. Parkins, Sarah K. Yelton, Megan Rodgers et al. "Monitoring Variations in Lake Water Storage with Satellite Imagery and Citizen Science". Water 13, n.º 7 (30 de marzo de 2021): 949. http://dx.doi.org/10.3390/w13070949.
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Despite lakes being a key part of the global water cycle and a crucial water resource, there is limited understanding of whether regional or lake-specific factors control water storage variations in small lakes. Here, we study groups of small, unregulated lakes in North Carolina, Washington, Illinois, and Wisconsin, USA using lake level measurements gathered by citizen scientists and lake surface area measurements from optical satellite imagery. We show the lake level measurements to be highly accurate when compared to automated gauges (mean absolute error = 1.6 cm). We compare variations in lake water storage between pairs of lakes within these four states. On average, water storage variations in lake pairs across all study regions are moderately positively correlated (ρ = 0.49) with substantial spread in the degree of correlation. The distance between lake pairs and the extent to which their changes in volume are correlated show a weak but statistically significant negative relationship. Our results indicate that, on regional scales, distance is not a primary factor governing lake water storage patterns, which suggests that other, perhaps lakes-specific, factors must also play important roles.
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Lefranc, Marie, Aurélie Thénot, Cécile Lepère y Didier Debroas. "Genetic Diversity of Small Eukaryotes in Lakes Differing by Their Trophic Status". Applied and Environmental Microbiology 71, n.º 10 (octubre de 2005): 5935–42. http://dx.doi.org/10.1128/aem.71.10.5935-5942.2005.
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ABSTRACT Small eukaryotes, cells with a diameter of less than 5 μm, are fundamental components of lacustrine planktonic systems. In this study, small-eukaryote diversity was determined by sequencing cloned 18S rRNA genes in three libraries from lakes of differing trophic status in the Massif Central, France: the oligotrophic Lake Godivelle, the oligomesotrophic Lake Pavin, and the eutrophic Lake Aydat. This analysis shows that the least diversified library was in the eutrophic lake (12 operational taxonomic units [OTUs]) and the most diversified was in the oligomesotrophic lake (26 OTUs). Certain groups were present in at least two ecosystems, while the others were specific to one lake on the sampling date. Cryptophyta, Chrysophyceae, and the strictly heterotrophic eukaryotes, Ciliophora and fungi, were identified in the three libraries. Among the small eukaryotes found only in two lakes, Choanoflagellida and environmental sequences (LKM11) were not detected in the eutrophic system whereas Cercozoa were confined to the oligomesotrophic and eutrophic lakes. Three OTUs, linked to the Perkinsozoa, were detected only in the Aydat library, where they represented 60% of the clones of the library. Chlorophyta and Haptophyta lineages were represented by a single clone and were present only in Godivelle and Pavin, respectively. Of the 127 clones studied, classical pigmented organisms (autotrophs and mixotrophs) represented only a low proportion regardless of the library's origin. This study shows that the small-eukaryote community composition may differ as a function of trophic status; certain lineages could be detected only in a single ecosystem.
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Williamson, Andrew G., Alison F. Banwell, Ian C. Willis y Neil S. Arnold. "Dual-satellite (Sentinel-2 and Landsat 8) remote sensing of supraglacial lakes in Greenland". Cryosphere 12, n.º 9 (26 de septiembre de 2018): 3045–65. http://dx.doi.org/10.5194/tc-12-3045-2018.
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Abstract. Remote sensing is commonly used to monitor supraglacial lakes on the Greenland Ice Sheet (GrIS); however, most satellite records must trade off higher spatial resolution for higher temporal resolution (e.g. MODIS) or vice versa (e.g. Landsat). Here, we overcome this issue by developing and applying a dual-sensor method that can monitor changes to lake areas and volumes at high spatial resolution (10–30 m) with a frequent revisit time (∼3 days). We achieve this by mosaicking imagery from the Landsat 8 Operational Land Imager (OLI) with imagery from the recently launched Sentinel-2 Multispectral Instrument (MSI) for a ∼12 000 km2 area of West Greenland in the 2016 melt season. First, we validate a physically based method for calculating lake depths with Sentinel-2 by comparing measurements against those derived from the available contemporaneous Landsat 8 imagery; we find close correspondence between the two sets of values (R2=0.841; RMSE = 0.555 m). This provides us with the methodological basis for automatically calculating lake areas, depths, and volumes from all available Landsat 8 and Sentinel-2 images. These automatic methods are incorporated into an algorithm for Fully Automated Supraglacial lake Tracking at Enhanced Resolution (FASTER). The FASTER algorithm produces time series showing lake evolution during the 2016 melt season, including automated rapid (≤4 day) lake-drainage identification. With the dual Sentinel-2–Landsat 8 record, we identify 184 rapidly draining lakes, many more than identified with either imagery collection alone (93 with Sentinel-2; 66 with Landsat 8), due to their inferior temporal resolution, or would be possible with MODIS, due to its omission of small lakes <0.125 km2. Finally, we estimate the water volumes drained into the GrIS during rapid-lake-drainage events and, by analysing downscaled regional climate-model (RACMO2.3p2) run-off data, the water quantity that enters the GrIS via the moulins opened by such events. We find that during the lake-drainage events alone, the water drained by small lakes (<0.125 km2) is only 5.1 % of the total water volume drained by all lakes. However, considering the total water volume entering the GrIS after lake drainage, the moulins opened by small lakes deliver 61.5 % of the total water volume delivered via the moulins opened by large and small lakes; this is because there are more small lakes, allowing more moulins to open, and because small lakes are found at lower elevations than large lakes, where run-off is higher. These findings suggest that small lakes should be included in future remote-sensing and modelling work.
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Baric, Ante, Branka Grbec, Grozdan Kuspilic, Ivona Marasovic, Zivana Nincevic y Ivana Grubelic. "Mass mortality event in a small saline lake (Lake Rogoznica) caused by unusual holomictic conditions". Scientia Marina 67, n.º 2 (30 de junio de 2003): 129–41. http://dx.doi.org/10.3989/scimar.2003.67n2129.
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MacKay, Murray D. "Incorporating wind sheltering and sediment heat flux into 1-D models of small boreal lakes: a case study with the Canadian Small Lake Model V2.0". Geoscientific Model Development 12, n.º 7 (17 de julio de 2019): 3045–54. http://dx.doi.org/10.5194/gmd-12-3045-2019.
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Abstract. Lake models are increasingly being incorporated into global and regional climate and numerical weather prediction systems. Lakes interact with their surroundings through flux exchange at their bottom sediments and with the atmosphere at the surface, and these linkages must be well represented in fully coupled prognostic systems in order to completely elucidate the role of lakes in the climate system. In this study schemes for the inclusion of wind sheltering and sediment heat flux simple enough to be included in any 1-D lake model are presented. Example simulations with the Canadian Small Lake Model show improvements in surface-wind-driven mixing and temperature in summer and a reduction of the bias in the change in heat content under ice compared with a published simulation based on an earlier version of the model.
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Ihssen, P. E., J. M. Casselman, G. W. Martin y R. B. Phillips. "Biochemical Genetic Differentiation of Lake Trout (Salvelinus namaycush) Stocks of the Great Lakes Region". Canadian Journal of Fisheries and Aquatic Sciences 45, n.º 6 (1 de junio de 1988): 1018–29. http://dx.doi.org/10.1139/f88-125.
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Allelic frequencies for lake trout (Salvelinus namaycush) samples collected from 27 small lakes or spawning shoals on larger lakes did not show significant annual changes. Levels of genetic variability were in the high range for Salmonidae, with 57% of the loci examined polymorphic (1% criterion) and 4.7% average heterozygosity per locus. Twenty-one percent of the total genetic variability was due to differences between stocks. Highly significant allelic frequency differences were found among allopatric as well as sympatric stocks. Genetic differences among sympatric stocks of Lake Superior indicated a significant degree of genetic isolation among these stocks. Genetic diversity within stocks, as measured by the proportion of polymorphic loci, was larger in stocks from large lakes than small lakes or transplanted stocks from large lakes into small lakes. Geographic patterns in allelic frequencies were observed. Samples from the northwestern range of our study area (upper Great Lakes, northwestern Ontario, and Manitoba) could be distinguished from those of the southeastern range by both allelic frequency differences and the presence or absence of alleles. We suggest that these two geographic ranges were colonized by lake trout that survived in different refugia during the Wisconsin glaciation. Unusual stocks of lake trout were found in three small lakes in the Haliburton Highlands of southern Ontario, with alleles at high frequencies that are rare or absent in most other stocks. We propose that the Haliburton Highlands lake trout originated from a glacial relict stock and survived during the last glaciation isolated from refugia used by other lake trout.
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Bergmann, Martin A. y Harold E. Welch. "Nitrogen Fixation by Epilithic Periphyton in Small Arctic Lakes in Response to Experimental Nitrogen and Phosphorus Fertilization". Canadian Journal of Fisheries and Aquatic Sciences 47, n.º 8 (1 de agosto de 1990): 1545–50. http://dx.doi.org/10.1139/f90-174.
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Epilithic periphyton played a moderate role in the nitrogen budget of four small arctic lakes located at Saqvaqjuac, N.W.T. The acetylene reduction technique used to estimate nitrogen fixation indicated that periphyton in 0–2 m water depth were capable of fixing up to 0.86 mg N∙m−2∙h−1 during the period of active nitrogen fixation from July to September 1981. Far Lake was fertilized with Phosphorus for 3 yr and had a higher rate of fixation than did a P- and N-fertilized lake or a control lake, in agreement with similar studies on temperate and subarctic lakes. A numerical model based on incoming light was used to perdict the amount of nitrogen fixed in each study lake throughout the season. The calculated contribution of periphyton to the overall N budget for 1981 was 5% for the P- and N-fertilized lake, 16% for the control lake and 28% for the P-only fertilized lake.
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Baup, F., F. Frappart y J. Maubant. "Combining high-resolution satellite images and altimetry to estimate the volume of small lakes". Hydrology and Earth System Sciences 18, n.º 5 (27 de mayo de 2014): 2007–20. http://dx.doi.org/10.5194/hess-18-2007-2014.
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Abstract. This study presents an approach to determining the volume of water in small lakes (<100 ha) by combining satellite altimetry data and high-resolution (HR) images. In spite of the strong interest in monitoring surface water resources on a small scale using radar altimetry and satellite imagery, no information is available about the limits of the remote-sensing technologies for small lakes mainly used for irrigation purposes. The lake being studied is located in the south-west of France and is only used for agricultural irrigation purposes. The altimetry satellite data are provided by an RA-2 sensor onboard Envisat, and the high-resolution images (<10 m) are obtained from optical (Formosat-2) and synthetic aperture radar (SAR) antenna (Terrasar-X and Radarsat-2) satellites. The altimetry data (data are obtained every 35 days) and the HR images (77) have been available since 2003 and 2010, respectively. In situ data (for the water levels and volumes) going back to 2003 have been provided by the manager of the lake. Three independent approaches are developed to estimate the lake volume and its temporal variability. The first two approaches (HRBV and ABV) are empirical and use synchronous ground measurements of the water volume and the satellite data. The results demonstrate that altimetry and imagery can be effectively and accurately used to monitor the temporal variations of the lake (R2ABV = 0.98, RMSEABV = 5%, R2HRBV = 0.90, and RMSEABV = 7.4%), assuming a time-varying triangular shape for the shore slope of the lake (this form is well adapted since it implies a difference inferior to 2% between the theoretical volume of the lake and the one estimated from bathymetry). The third method (AHRBVC) combines altimetry (to measure the lake level) and satellite images (of the lake surface) to estimate the volume changes of the lake and produces the best results (R2AHRBVC = 0.98) of the three methods, demonstrating the potential of future Sentinel and SWOT missions to monitor small lakes and reservoirs for agricultural and irrigation applications.
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López-Espinoza, Ruiz-Angulo, Zavala-Hidalgo, Romero-Centeno y Escamilla-Salazar. "Impacts of the Desiccated Lake System on Precipitation in the Basin of Mexico City". Atmosphere 10, n.º 10 (17 de octubre de 2019): 628. http://dx.doi.org/10.3390/atmos10100628.
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Mexico City constitutes one of the largest concentrations of population on the planet and is settled in a valley that, before the 16th century, had a lake system. The lakes were desiccated artificially, and currently, only small lakes remain. The impact of the lake system desiccation on precipitation was studied by performing numerical experiments: with the ancient lake system and without it. The experiments were carried out with the Weather Research and Forecasting (WRF) model coupled with a lake model for two months, using identical initial and boundary conditions, where only the system and lake physics were changed. The mean daily accumulated precipitation reduced when the system was removed. Additionally, the hourly distribution of rainfall changed from a relatively small diurnal variability when there was a lake system to a larger variability with a peak in the afternoon when the system was removed. Extreme precipitation events became more intense in the simulations with lakes. When the lakes were removed, the diurnal temperature range increased, and the boundary layer height became more variable, with a higher daily maximum. The results presented here show that the WRF-Lake model leads to opposite results compared to those with a non-coupled lake.
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Kelso, J. R. M. y M. G. Johnson. "Factors Related to the Biomass and Production of Fish Communities in Small, Oligotrophic Lakes Vulnerable to Acidification". Canadian Journal of Fisheries and Aquatic Sciences 48, n.º 12 (1 de diciembre de 1991): 2523–32. http://dx.doi.org/10.1139/f91-293.
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We estimated biomass and production of the fish community in 19 small (<50 ha) lakes from four watersheds in central Ontario. Lake pH ranged from 4.8 to 7.1. We found 19 fish species in these lakes; yellow perch (Perca flavescens), pumpkinseed (Lepomis gibbosus), white sucker (Catostomus commersoni), and largemouth bass (Micropterus salmoides) were the most common. On average, there were 4.5 species per lake. Neither fish community biomass nor production was significantly different among the communities identified by cluster analysis, and the number offish species was not lower at lower pH. More than 75% of each lake's total biomass was confined to less than three fish species. Whole-lake fish biomass was related to the total number of species in the lakes and their average age. Fish community production was related to fish biomass, averge fish size, and acid neutralizing capacity (ANC) with an almost equal influence provided by each factor. At lower ANC and pH, fish were usually smaller in weight and often had lower population growth rates. In these lakes where the influence of lake size and trophic status was minimized, fish community biomass and production were only secondarily related to lake pH or ANC.
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Zahajská, Petra, Carolina Olid, Johanna Stadmark, Sherilyn C. Fritz, Sophie Opfergelt y Daniel J. Conley. "Modern silicon dynamics of a small high-latitude subarctic lake". Biogeosciences 18, n.º 7 (13 de abril de 2021): 2325–45. http://dx.doi.org/10.5194/bg-18-2325-2021.
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Abstract. High biogenic silica (BSi) concentrations occur sporadically in lake sediments throughout the world; however, the processes leading to high BSi concentrations vary. We explored the factors responsible for the high BSi concentration in sediments of a small, high-latitude subarctic lake (Lake 850). The Si budget of this lake had not been fully characterized before to establish the drivers of BSi accumulation in this environment. To do this, we combined measurements of variations in stream discharge, dissolved silica (DSi) concentrations, and stable Si isotopes in both lake and stream water with measurements of BSi content in lake sediments. Water, radon, and Si mass balances revealed the importance of groundwater discharge as a main source of DSi to the lake, with groundwater-derived DSi inputs 3 times higher than those from ephemeral stream inlets. After including all external DSi sources (i.e., inlets and groundwater discharge) and estimating the total BSi accumulation in the sediment, we show that diatom production consumes up to 79 % of total DSi input. Additionally, low sediment accumulation rates were observed based on the dated gravity core. Our findings thus demonstrate that groundwater discharge and low mass accumulation rate can account for the high BSi accumulation during the last 150 cal yr BP. Globally, lakes have been estimated to retain one-fifth of the annual DSi terrestrial weathering flux that would otherwise be delivered to the ocean. Well-constrained lake mass balances, such as presented here, bring clarity to those estimates of the terrestrial Si cycle sinks.
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Juutinen, S., M. Rantakari, P. Kortelainen, J. T. Huttunen, T. Larmola, J. Alm, J. Silvola y P. J. Martikainen. "Methane dynamics in different boreal lake types". Biogeosciences 6, n.º 2 (16 de febrero de 2009): 209–23. http://dx.doi.org/10.5194/bg-6-209-2009.
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Abstract. This study explores the variability in concentrations of dissolved CH4 and annual flux estimates in the pelagic zone in a statistically defined sample of 207 lakes in Finland. The lakes were situated in the boreal zone, in an area where the mean annual air temperature ranges from −2.8 to 5.9°C. We examined how lake CH4 dynamics related to regional lake types assessed according to the EU water framework directive. Ten lake types were defined on the basis of water chemistry, color, and size. Lakes were sampled for dissolved CH4 concentrations four times per year, at four different depths at the deepest point of each lake. We found that CH4 concentrations and fluxes to the atmosphere tended to be high in nutrient rich calcareous lakes, and that the shallow lakes had the greatest surface water concentrations. Methane concentration in the hypolimnion was related to oxygen and nutrient concentrations, and to lake depth or lake area. The surface water CH4 concentration was related to the depth or area of lake. Methane concentration close to the bottom can be viewed as proxy of lake status in terms of frequency of anoxia and nutrient levels. The mean pelagic CH4 release from randomly selected lakes was 49 mmol m−2 a−1. The sum CH4 flux (storage and diffusion) correlated with lake depth, area and nutrient content, and CH4 release was greatest from the shallow nutrient rich and humic lakes. Our results support earlier lake studies regarding the regulating factors and also the magnitude of global emission estimate. These results propose that in boreal region small lakes have higher CH4 fluxes per unit area than larger lakes, and that the small lakes have a disproportionate significance regarding to the CH4 release.
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Umi, Wahidah Ahmad Dini, Fatimah Md Yusoff, Ahmad Zaharin Aris, Zati Sharip y Artem Y. Sinev. "Planktonic Microcrustacean Community Structure Varies with Trophic Status and Environmental Variables in Tropical Shallow Lakes in Malaysia". Diversity 12, n.º 9 (24 de agosto de 2020): 322. http://dx.doi.org/10.3390/d12090322.
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A study was conducted to evaluate planktonic microcrustacean species composition, abundance, and diversity in lakes with different trophic status and to determine the relationship between microcrustacean community structure and lake environmental conditions. This study hypothesized that there are correlations between eutrophication levels and microcrustacean community structures in a lake. Three shallow lakes of different trophic status (Sembrong, Putrajaya and Subang lakes) were selected for this study. Two-Way Analysis of similarities (ANOSIM) revealed differences in microcrustacean diversity and density amongst lakes, where the hypereutrophic condition in Sembrong lake resulted in the lowest diversity but the highest density of microcrustaceans. Similarity percentage (SIMPER) analysis identified the discriminator species among lakes where the domination of small-sized microcrustaceans was observed in lakes with high levels of eutrophication; the hypereutrophic Sembrong lake (Ceriodaphnia cornuta, 74.0%); the meso-eutrophic Putrajaya lake (Bosmina longirostris, 46.9%; C. cornuta, 19.4%). Chlorophyll a, total phosphorus and water transparency showed significant roles in the distribution of microcrustaceans. The canonical correspondence analysis (CCA) scores indicated that small-sized C. cornuta and B. longirostris were related to the eutrophic conditions of lakes. This study elucidated that the lake trophic status could be one of the main factors contributing to the community restructuring of microcrustaceans in tropical lakes.
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Fedorov y Ruban. "Geoheritage Resource of Small Mud Lakes in the Semi-Arid Environments of the Russian South". Resources 8, n.º 2 (20 de abril de 2019): 75. http://dx.doi.org/10.3390/resources8020075.
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Lakes constitute a significant freshwater resource and are often regarded as being an important part of a country’s natural heritage. However, their geological heritage (geoheritage) value remains significantly understudied. Three small lakes, namely the Salt Lake, the Gruzskoe Lake and the Big Yashalta Lake, located in the central part of the Russian South were studied in this paper. The main focus of this research was to search for relevant unique geological features. This paper established that these lakes are distinguishable from other lakes by the presence of dark-colored mud that is rich in sulfides and methane. As a result of excessive summer evaporation, the lakes desiccate (partly or even fully) and this results in exposure of the mud as well as the formation of salt crystals and crusts. This bottom mud (peloid, therapeutic mud) forms as a result of highly-complex biogeochemical processes in semi-arid environments. This mud is interpreted as being part of the lake’s geoheritage as it belongs to sedimentary, geochemical and other types. Moreover, this geoheritage has a high ranking nationally. The most representative example can be found at the Big Yashalta Lake and for that reason, this lake is proposed as a geosite. Established sites of geoheritage importance are vital to geoscience research and geotourism activities and thus, these sites are considered to be a resource. Together with the development of local ecotourism and the use of peloids for the health industry purposes, the exploitation of this geoheritage resource would contribute to the sustainable development of the local area.
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Cornett, R. J. y L. Chant. "Pu Residence Times in Freshwaters and Accumulation in Shield Lake Sediments". Canadian Journal of Fisheries and Aquatic Sciences 45, n.º 3 (1 de marzo de 1988): 407–15. http://dx.doi.org/10.1139/f88-049.
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Activity balances for 239,240Pu in seven oligotrophic lakes were constructed from measurements of 239,240Pu inputs and measurements of 239,240Pu accumulated in the lake sediments. 239,240Pu eroded from the catchment was a significant input to lakes with rapid hydrologic flushing rates. From 28 to 100% of the 239,240Pu input to the lakes accumulated in the lake sediments. The fraction of 239,240Pu inputs accumulated in the lake sediments was inversely correlated with the hydrologic flushing rate of the lake. 239,240Pu concentrations in the sediments were simulated using a single reservoir input–output model. Partial residence times for 239,240Pu transfer from the water to the sediments ranged from 0.09 to 2.7 yr and were shorter in lakes with more rapid flushing. Partial residence times of 239,240Pu in these small shield lakes were very similar to the residence times of 239,240Pu in the Laurentian Great Lakes and to those of 137Cs and 210Pb in other small oligotrophic lakes.
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Dembowska, Ewa A. y Patrycja L. Pul. "Water quality assessment in a shallow lake used for tourism". Limnological Review 15, n.º 4 (1 de diciembre de 2015): 155–64. http://dx.doi.org/10.2478/limre-2015-0016.
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Abstract The routine evaluation of water quality is limited to lakes with the largest area. In Poland, only lakes with an area exceeding 50 hectares are monitored by the State Environmental Monitoring System. For many local communities, however, small lakes are more important. This applies mainly to areas with a small number of lakes, where even the smallest lakes are used for various purposes. This paper presents the results of phytoplankton analysis in a small and shallow lake used for recreation. The study was conducted at three sites located in different parts of the lake. A total of 122 algae taxa were identified in the phytoplankton, mainly diatoms and green algae. The most constant taxa in the lake were: Stephanodiscus hantzschii, Desmodesmus communis, Pediastrum tetras and Crucigenia tetrapedia. The average phytoplankton biomass was 37 mg l−1. The maximum biomass, almost 140 mg dm−3, was recorded in late July at the site located near the beach. At that time, there was a massive cyanobacterial bloom composed of Microcystis wesenbergii and Aphanizomenon issatschenkoi. Based on these studies, the lake should be classified as hypertrophic with bad ecological status. This lake should not be used for recreational purposes in the current state.
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Deng, Xiaoli, Ren-Bin Wang, Fukai Peng, Yong Yang y Nan-Ming Mo. "Retracking Cryosat-2 Data in SARIn and LRM Modes for Plateau Lakes: A Case Study for Tibetan and Dianchi Lakes". Remote Sensing 13, n.º 6 (12 de marzo de 2021): 1078. http://dx.doi.org/10.3390/rs13061078.
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This paper estimates lake level variations over two small and adjacent lakes in the Tibetan plateau (TP), namely Gemang Co and Zhangnai Co, as well as the inland Dianchi Lake in China using CryoSat-2 SARIn-mode and LRM 20-Hz waveforms over the period of 2011–2018. Different retrackers and a dedicated data editing procedure have been used to process CryoSat-2 data for determining the lake level time series. The lake level estimations are indirectly validated against those from Jason-2 in TP and from in situ data in Dianchi Lake, both showing good agreement with strong correlation coefficients >0.74. The results of this paper suggest that the official ICE retracker for LRM data and APD-PPT retracker for SARIn-mode waveforms are the most appropriate retrackers over Dianchi Lake and TP lakes, respectively. The trend estimates of the time series derived by both retrackers are 61.0 ± 10.8 mm/yr for Gemang Co and Zhangnai Co in TP, and 30.9 ± 64.9 mm/yr for Dianchi Lake, indicating that the lake levels over three lakes were continuously rising over the study period. The results of this study show that CryoSat-2 SARIn-mode data can be used for monitoring many small lakes that have not been measured by other altimetry missions in TP.
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Granger, R. J. y N. Hedstrom. "Modelling hourly rates of evaporation from small lakes". Hydrology and Earth System Sciences 15, n.º 1 (21 de enero de 2011): 267–77. http://dx.doi.org/10.5194/hess-15-267-2011.
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Abstract. The paper presents the results of a field study of open water evaporation carried out on three small lakes in Western and Northern Canada. In this case small lakes are defined as those for which the temperature above the water surface is governed by the upwind land surface conditions; that is, a continuous boundary layer exists over the lake, and large-scale atmospheric effects such as entrainment do not come into play. Lake evaporation was measured directly using eddy covariance equipment; profiles of wind speed, air temperature and humidity were also obtained over the water surfaces. Observations were made as well over the upwind land surface. The major factors controlling open water evaporation were examined. The study showed that for time periods shorter than daily, the open water evaporation bears no relationship to the net radiation; the wind speed is the most significant factor governing the evaporation rates, followed by the land-water temperature contrast and the land-water vapour pressure contrast. The effect of the stability on the wind field was demonstrated; relationships were developed relating the land-water wind speed contrast to the land-water temperature contrast. The open water period can be separated into two distinct evaporative regimes: the warming period in the Spring, when the land is warmer than the water, the turbulent fluxes over water are suppressed; and the cooling period, when the water is warmer than the land, the turbulent fluxes over water are enhanced. Relationships were developed between the hourly rates of lake evaporation and the following significant variables and parameters (wind speed, land-lake temperature and humidity contrasts, and the downwind distance from shore). The result is a relatively simple versatile model for estimating the hourly lake evaporation rates. The model was tested using two independent data sets. Results show that the modelled evaporation follows the observed values very well; the model follows the diurnal trends and responds to changes in environmental conditions.
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Nürnberg, Gertrud K., Margo Shaw, Peter J. Dillon y Don J. McQueen. "Internal Phosphorus Load in an Oligotrophic Precambrian Shield Lake with an Anoxic Hypolimnion". Canadian Journal of Fisheries and Aquatic Sciences 43, n.º 3 (1 de marzo de 1986): 574–80. http://dx.doi.org/10.1139/f86-068.
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The release of phosphorus from sediments into the anoxic water of oligotrophic Chub Lake, Ontario, determined with three different methods, showed that the average release rate of 2.2 mg∙m−2∙d−1 is much smaller than release rates of more eutrophic lakes (14 mg∙m−2∙d−1). Our hypothesis that anoxic release rates depend on lake trophy was confirmed by the significant positive regression of release rates on lake phosphorus concentrations for 56 lakes from the literature. Despite a comparably small phosphorus release rate, the sediments play an important role in Chub Lake as a source of phosphorus because phosphorus from internal sources is in a highly available form and external loads are small.
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Baup, F., F. Frappart y J. Maubant. "Combining high-resolution satellite images and altimetry to estimate the volume of small lakes". Hydrology and Earth System Sciences Discussions 10, n.º 12 (20 de diciembre de 2013): 15731–70. http://dx.doi.org/10.5194/hessd-10-15731-2013.
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Abstract. This study presents an approach to determine the volume of water in small lakes (<100 ha) by combining satellite altimetry data and high-resolution (HR) images. The lake being studied is located in the south-west of France and is only used for agricultural irrigation purposes. The altimetry satellite data are provided by RA-2 sensor on board Envisat, and the high-resolution images (<10 m) are obtained from optical (Formosat-2) and synthetic aperture radar (SAR) sensors (Terrasar-X and Radarsat-2) satellites. The altimetry data (data are obtained every 35 days) and the HR images (45) have been available since 2003 and 2010, respectively. In situ data (for the water levels and volumes) going back to 2003 have been provided by the manager of the lake. Three independent approaches are developed to estimate the lake volume and its temporal variability. The first two approaches are empirical and use synchronous ground measurements of the water volume and the satellite data. The results demonstrate that altimetry and imagery can be effectively and accurately used to monitor the temporal variations of the lake (R2altimetry = 0.97, RMSEaltimetry = 5.2%, R2imagery = 0.90, and RMSEimagery = 7.4%). The third method combines altimetry (to measure the lake level) and satellite images (of the lake surface) to estimate the volume changes of the lake and produces the best results (R2 = 0.99) of the three methods, demonstrating the potential of future Sentinel and SWOT missions to monitor small lakes and reservoirs for agricultural and irrigation applications.
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García, Antonio Francisco y Martin Stokes. "Late Pleistocene highstand and recession of a small, high-altitude pluvial lake, Jakes Valley, central Great Basin, USA". Quaternary Research 65, n.º 1 (enero de 2006): 179–86. http://dx.doi.org/10.1016/j.yqres.2005.08.025.
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AbstractModels of factors controlling late Pleistocene pluvial lake-level fluctuations in the Great Basin are evaluated by dating lake levels in Jakes Valley. “Jakes Lake” rose to a highstand at 13,870 ± 50 14C Yr B.P., receded to a stillstand at 12,440 ± 50 14C yr B.P., and receded steadily to desiccation thereafter. The Jakes Lake highstand is roughly coincident with highstands of lakes Bonneville, Lahontan and Russell. The rise to highstand and recession of Jakes Lake were most likely controlled by a storm track steered by the polar jet stream. The final stillstand of Jakes Lake helps constrain timing of northward retreat of the polar jet stream during the Pleistocene–Holocene transition.
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Stenson, Jan A. E. y Stig Aronsson. "Newt-fish interactions in a small forest lake". Amphibia-Reptilia 16, n.º 2 (1995): 177–84. http://dx.doi.org/10.1163/156853895x00352.
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AbstractFishes and newts may play similar roles at the same trophic level in freshwater lakes and ponds. Although a great deal is known about the predatory and competitive impact of fish on most freshwater groups, very little is known about fish-newt interactions. In the present work we have studied the influence of a fish population on the distribution and structure of a Triturus vulgaris population. The roach, Rutilus rutilus (L.), in a small forest lake were eliminated experimentally and were reintroduced after six years. Newts appeared in the lake and showed a rapid population increase after the elimination of fish. After the reintroduction offish, the recruitment of young newts virtually ceased and the population decreased. The most probable explanation is that fish prey upon newt larvae, this being supported by our field and laboratory results. Access to water bodies without significant predators and competitors is thus of vital importance for newt populations.
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Zhang, Shuai y Tamlin M. Pavelsky. "Remote Sensing of Lake Ice Phenology across a Range of Lakes Sizes, ME, USA". Remote Sensing 11, n.º 14 (20 de julio de 2019): 1718. http://dx.doi.org/10.3390/rs11141718.
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Remote sensing of ice phenology for small lakes is hindered by a lack of satellite observations with both high temporal and spatial resolutions. By merging multi-source satellite data over individual lakes, we present a new algorithm that successfully estimates ice freeze and thaw timing for lakes with surface areas as small as 0.13 km2 and obtains consistent results across a range of lake sizes. We have developed an approach for classifying ice pixels based on the red reflectance band of Moderate Resolution Imaging Spectroradiometer (MODIS) imagery, with a threshold calibrated against ice fraction from Landsat Fmask over each lake. Using a filter derived from the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2) surface air temperature product, we removed outliers in the time series of lake ice fraction. The time series of lake ice fraction was then applied to identify lake ice breakup and freezeup dates. Validation results from over 296 lakes in Maine indicate that the satellite-based lake ice timing detection algorithm perform well, with mean absolute error (MAE) of 5.54 days for breakup dates and 7.31 days for freezeup dates. This algorithm can be applied to lakes worldwide, including the nearly two million lakes with surface area between 0.1 and 1 km2.
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Mooney, Robert J., Emily H. Stanley, William C. Rosenthal, Peter C. Esselman, Anthony D. Kendall y Peter B. McIntyre. "Outsized nutrient contributions from small tributaries to a Great Lake". Proceedings of the National Academy of Sciences 117, n.º 45 (26 de octubre de 2020): 28175–82. http://dx.doi.org/10.1073/pnas.2001376117.
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Excessive nitrogen (N) and phosphorus (P) loading is one of the greatest threats to aquatic ecosystems in the Anthropocene, causing eutrophication of rivers, lakes, and marine coastlines worldwide. For lakes across the United States, eutrophication is driven largely by nonpoint nutrient sources from tributaries that drain surrounding watersheds. Decades of monitoring and regulatory efforts have paid little attention to small tributaries of large water bodies, despite their ubiquity and potential local importance. We used a snapshot of nutrient inputs from nearly all tributaries of Lake Michigan—the world’s fifth largest freshwater lake by volume—to determine how land cover and dams alter nutrient inputs across watershed sizes. Loads, concentrations, stoichiometry (N:P), and bioavailability (percentage dissolved inorganic nutrients) varied by orders of magnitude among tributaries, creating a mosaic of coastal nutrient inputs. The 6 largest of 235 tributaries accounted for ∼70% of the daily N and P delivered to Lake Michigan. However, small tributaries exhibited nutrient loads that were high for their size and biased toward dissolved inorganic forms. Higher bioavailability of nutrients from small watersheds suggests greater potential to fuel algal blooms in coastal areas, especially given the likelihood that their plumes become trapped and then overlap in the nearshore zone. Our findings reveal an underappreciated role that small streams may play in driving coastal eutrophication in large water bodies. Although they represent only a modest proportion of lake-wide loads, expanding nutrient management efforts to address smaller watersheds could reduce the ecological impacts of nutrient loading on valuable nearshore ecosystems.
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Lara, Mark Jason y Melissa Lynn Chipman. "Periglacial Lake Origin Influences the Likelihood of Lake Drainage in Northern Alaska". Remote Sensing 13, n.º 5 (25 de febrero de 2021): 852. http://dx.doi.org/10.3390/rs13050852.
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Nearly 25% of all lakes on earth are located at high latitudes. These lakes are formed by a combination of thermokarst, glacial, and geological processes. Evidence suggests that the origin of periglacial lake formation may be an important factor controlling the likelihood of lakes to drain. However, geospatial data regarding the spatial distribution of these dominant Arctic and subarctic lakes are limited or do not exist. Here, we use lake-specific morphological properties using the Arctic Digital Elevation Model (DEM) and Landsat imagery to develop a Thermokarst lake Settlement Index (TSI), which was used in combination with available geospatial datasets of glacier history and yedoma permafrost extent to classify Arctic and subarctic lakes into Thermokarst (non-yedoma), Yedoma, Glacial, and Maar lakes, respectively. This lake origin dataset was used to evaluate the influence of lake origin on drainage between 1985 and 2019 in northern Alaska. The lake origin map and lake drainage datasets were synthesized using five-year seamless Landsat ETM+ and OLI image composites. Nearly 35,000 lakes and their properties were characterized from Landsat mosaics using an object-based image analysis. Results indicate that the pattern of lake drainage varied by lake origin, and the proportion of lakes that completely drained (i.e., >60% area loss) between 1985 and 2019 in Thermokarst (non-yedoma), Yedoma, Glacial, and Maar lakes were 12.1, 9.5, 8.7, and 0.0%, respectively. The lakes most vulnerable to draining were small thermokarst (non-yedoma) lakes (12.7%) and large yedoma lakes (12.5%), while the most resilient were large and medium-sized glacial lakes (4.9 and 4.1%) and Maar lakes (0.0%). This analysis provides a simple remote sensing approach to estimate the spatial distribution of dominant lake origins across variable physiography and surficial geology, useful for discriminating between vulnerable versus resilient Arctic and subarctic lakes that are likely to change in warmer and wetter climates.
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Keller, W. y M. Conlon. "Crustacean Zooplankton Communities and Lake Morphometry in Precambrian Shield Lakes". Canadian Journal of Fisheries and Aquatic Sciences 51, n.º 11 (1 de noviembre de 1994): 2424–34. http://dx.doi.org/10.1139/f94-242.
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To investigate relationships between crustacean zooplankton communities and lake morphometry we sampled 60 near-neutral Precambrian Shield lakes, including many small, shallow lakes. Morphometry-related patterns in the distributions of many zooplankton species were evident. Lake depth determined the occurrence of hypolimnetic species, and lake depth, lake area, and watershed area were positively related to the species richness of zooplankton communities. Among lakes with fish, deeper (maximum depth >8 m) lakes were characterized by greater species richness, higher abundances of a number of species including Daphnia pulex, Daphnia galeata mendotae, Daphnia dubia, and Diacyclops bicuspidatus thomasi, and lower abundances of Leptodiaptomus minutus, than shallower (maximum depth <8 m) lakes. Increased predation pressure by small fish species in smaller, shallower lakes probably influenced the observed species distributions. Lakes inferred to be fishless based on the presence of Chaoborus americanus typically had relatively high abundances of D. pulex, Diaphanosoma brachyurum, and Aglaodiaptomus leptopus, and absences of D. g. mendotae and D. birgei, patterns attributable to intense invertebrate predation on zooplankton.
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Grantham, Brian A. y Brenda J. Hann. "Leeches (Annelida: Hirudinea) in the Experimental Lakes Area, Northwestern Ontario, Canada: Patterns of Species Composition in Relation to Environment". Canadian Journal of Fisheries and Aquatic Sciences 51, n.º 7 (1 de julio de 1994): 1600–1607. http://dx.doi.org/10.1139/f94-159.
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Canonical correspondence analysis (CCA) was used to examine the distribution of leeches (Annelida: Hirudinea) in 18 lakes at the Experimental Lakes Area (ELA). Leech community composition was best described by an ordination incorporating alkalinity, primary productivity, and lake area. In general, highest species richness occurred in small, eutrophic lakes whereas lowest richness was recorded in medium to large lakes with low productivity. Contrary to results for some other taxa, lake pH was not a dominant variable, describing only a small amount of variance in the species–environment relationship.
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Tórz, Agnieszka, Małgorzata Bonisławska, Agnieszka Rybczyk, Arkadiusz Nędzarek y Adam Tański. "Susceptibility to Degradation, the Causes of Degradation, and Trophic State of Three Lakes in North-West Poland". Water 12, n.º 6 (7 de junio de 2020): 1635. http://dx.doi.org/10.3390/w12061635.
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Effective protection of lakes against degradation requires a detailed recognition of the factors leading to their eutrophication. This also pertains to small lakes, which constitute an important element of various ecosystems and are crucial for maintaining biodiversity. Therefore, the aim of the study is to determine the trophic state as well as the susceptibility to degradation of three small lakes in north-western Poland: Maszewo, Starzyca, and Nowogardzkie. This study analyzes the morphometric characteristics of the lakes, the impact of the catchment, their actual trophic state, and phosphorus levels. The analysis showed varying regeneration potentials of the lakes. Maszewo Lake is eutrophic-hypertrophic, nonresilient, strongly exposed to influence from the catchment, with phosphorus levels within the norm. Starzyca Lake is a eutrophic lake, not very resilient to the influence of the catchment, with excessive phosphorus levels. Nowogardzkie Lake is a eutrophic lake with moderate resilience to degradation, but with excessive phosphorus levels, which endangers the functioning of this aquatic ecosystem. In all the lakes, phosphorus supply was predominantly internal. Restoration of these lakes could be performed by completely cutting off the inflow of nutrients, as well as reclamation involving the deactivation of phosphorus (e.g., by precipitation) as well as the removal of the bottom sediments responsible for the internal supply of phosphorus.
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Zimmerman, Mara S., Stephanie N. Schmidt, Charles C. Krueger, M. Jake Vander Zanden y Randy L. Eshenroder. "Ontogenetic niche shifts and resource partitioning of lake trout morphotypes". Canadian Journal of Fisheries and Aquatic Sciences 66, n.º 6 (junio de 2009): 1007–18. http://dx.doi.org/10.1139/f09-060.
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Resource polymorphisms are widely observed in fishes; however, ontogenetic contributions to morphological and ecological differences are poorly understood. This study examined whether ontogenetic changes in niche partitioning could explain morphological and buoyancy differences between lake trout ( Salvelinus namaycush ) morphotypes in Great Slave Lake (Northwest Territories, Canada). Morphometric analysis, buoyancy, capture depth, diet, and stable isotope data were used in concert to determine whether (i) differences occur in small, as well as large, lake trout, (ii) ontogenetic changes in morphology and buoyancy correlate with shifts in depth or diet, and (iii) a subset of small trout, putatively identified as “humpers”, are distinct from other morphotypes. Ontogenetic changes in lake trout morphology were associated with an ecological shift between benthic and pelagic feeding. Resource partitioning between lean and siscowet-like trout occurred within benthic (small trout) and pelagic (large trout) habitats. The humper subset did not differ from small siscowet-like trout. By combining multiple methods and an ontogenetic perspective, our study provides novel perspectives on resource polymorphisms in large, deep lakes and on existing interpretations of stable isotope data from large lakes in general.
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Welch, Harold E., John K. Jorgenson y Martin F. Curtis. "Emergence of Chironomidae (Diptera) in Fertilized and Natural Lakes at Saqvaqjuac, N.W.T." Canadian Journal of Fisheries and Aquatic Sciences 45, n.º 4 (1 de abril de 1988): 731–37. http://dx.doi.org/10.1139/f88-088.
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Chironomid emergence was quantified in four small lakes at Saqvaqjuac, N.W.T. (63°39′N), before and after lake fertilization. Emerging biomass responded immediately to increased phytoplankton production, reaching equilibrium the following year. Emergence from the reference lake was extremely variable, for no apparent reason. The emergence – phytoplankton production relationships found by Davies for the Experimental Lakes Area (~49°N) were generally valid for Saqvaqjuac lakes and Char Lake (74°42′), except that (1) biomass was better correlated than numbers because of increased mean size with increasing latitude and (2) total primary production was a better predictor than phytoplankton production alone because benthic photosynthesis increases with increasing latitude. Chironomid production seems to be a predictable function of total primary production throughout the latitudinal range of the small Canadian lakes examined.
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HANSON, PAUL C., STEPHEN R. CARPENTER, JEFFREY A. CARDILLE, MICHAEL T. COE y LUKE A. WINSLOW. "Small lakes dominate a random sample of regional lake characteristics". Freshwater Biology 52, n.º 5 (mayo de 2007): 814–22. http://dx.doi.org/10.1111/j.1365-2427.2007.01730.x.
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Sevindik, Tuğba Ongun, Hatice Tunca, Halim Aytekin Ergül, Arzu Morkoyunlu Yüce, Melih Kayal, Nazmi Kağnicioğlu, Fatih Ekmekçi, Oltan Canli y Elmas Öktem Olgun. "Lake morphometry underlies physical and chemical parameters affecting the distribution of phytoplankton functional groups in lakes of the Sakarya River Basin (Turkey)". Fundamental and Applied Limnology / Archiv für Hydrobiologie 194, n.º 2 (9 de diciembre de 2020): 125–40. http://dx.doi.org/10.1127/fal/2020/1338.
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To test the effects of lake morphometry (lake size and depth) on water quality parameters which affect the phytoplankton functional groups (FG) distribution, phytoplankton and some environmental parameters were sampled in November 2017 and May 2018 at the two or three monitoring stations in nine Lakes of Sakarya River Basin (Turkey). Lake size and depth affected phytoplankton FG distribution in both large-sized and small-sized lakes by affecting light availability which was mainly driven by the mixing events during the studied period. Al- though PO4 -P and alkalinity were the other main environmental constraints influencing phytoplankton distribution, they were not directly affected by lake morphometry. Codon Lo was mainly found in small-sized and shallow lakes, whereas coda B, C, D, J, R, and T, which do not have active buoyancy regulation and adapt to high Zmix/Zeu con- ditions, occurred with high relative biovolume in large-sized water bodies.
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Elo, Aija-Riitta. "Modelling of summer stratification of morphologically different lakes". Hydrology Research 36, n.º 3 (1 de junio de 2005): 281–94. http://dx.doi.org/10.2166/nh.2005.0021.
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The use of a one-dimensional lake temperature model was investigated using long series of meteorological input data. These data were mainly based on one station. Effects of morphology on water temperature conditions were considered over this long period. The studied lakes are from the Finnish Lake District. Concerning their dynamics, they are small with areas ranging from 257 km2 to 0.14 km2 with the largest depth about 80 m, but typically less than 50 m. The strength of thermal stratification varies. Verification was made using test summers: for two larger lakes longer periods could be used. Summer stratification periods could finally be resolved satisfactorily, but only after adjusting with data from each lake. For some years the vertical temperature simulations are not as successful as for others, indicating the importance of local weather differences. For lakes with a large area to depth ratio heat is absorbed freely, while when it is small heat is blocked more into the epilimnion. For very small lakes sheltering is essential. Large total volume delays cooling, when stratification prevails. Sheltering is important and also very small lakes cool slowly due to their strong stability.
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Cahill, Kendra L., John M. Gunn y Martyn N. Futter. "Modelling ice cover, timing of spring stratification, and end-of-season mixing depth in small Precambrian Shield lakes". Canadian Journal of Fisheries and Aquatic Sciences 62, n.º 9 (1 de septiembre de 2005): 2134–42. http://dx.doi.org/10.1139/f05-127.
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From a 3-year study of 21 northern Ontario lakes, models were developed to determine the duration of ice cover, predict the timing of spring stratification, and predict the end-of-season mixing depth. The model to determine lake freeze and thaw dates was based on the daily variability of water temperature measured with a data logger suspended 1 and 2 m below the surface. The model to predict the duration of time (days) from lake thaw to lake stratification was developed using the mean May air temperature (degrees Celsius), dissolved organic carbon, and lake surface area (r2 = 0.79). The end-of-season mixing depth was best predicted using days to stratification and dissolved organic carbon concentration (r2 = 0.72). By applying a simple climate change scenario model, we were able to show that increased air temperature, rather than increased water clarity, was the most important factor affecting the timing of stratification. In contrast, lake clarity was the most important factor affecting end-of-season mixing depth in small Shield lakes.
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Rücker, Jacqueline, Brigitte Nixdorf, Katrin Quiel y Björn Grüneberg. "North German Lowland Lakes Miss Ecological Water Quality Standards—A Lake Type Specific Analysis". Water 11, n.º 12 (2 de diciembre de 2019): 2547. http://dx.doi.org/10.3390/w11122547.
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Despite great efforts in point source reductions due to improved wastewater treatment since 1990, more than 70% of the lakes in Germany have not yet achieved the “good ecological status” according to the European Water Framework Directive (WFD). To elicit lake type-specific causes of this failure, we firstly analyzed the ecological status of 183 lakes in NE Germany (Federal State of Brandenburg), as reported to the European Commission in 2015. Secondly, long-term data of two typical lakes (a very shallow polymictic lake with a large and a deep stratified lake with a small catchment area in relation to lake volume) and nutrient load from the common catchment were investigated. About 64%–83% of stratified and even 96% of polymictic shallow lakes in Brandenburg currently fail the WFD aims. Excessive nutrient emissions from agriculture were identified as the main cause of this failure. While stratified deep lakes with small catchments have the best chances of recovery, the deficits in catchment management are amplified downstream in lake chains, so that especially shallow lakes in a large catchment are unlikely to reach good ecological conditions. If the objectives of the WFD are not questioned, agricultural practices and approaches in land use have to be fundamentally improved.
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Campbell, Celina, Ian D. Campbell y Edward H. Hogg. "Lake Area Variability Across a Climatic and Vegetational Transect in Southeastern Alberta". Géographie physique et Quaternaire 48, n.º 2 (30 de noviembre de 2007): 207–12. http://dx.doi.org/10.7202/032997ar.
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ABSTRACTAreas of 34 small lakes forming a transect across the southern margin of the Boreal Forest into the Grassland in southern Alberta were obtained from 326 aerial photographs, with at least six photographs for each lake in different months and different years from 1949 to 1992. Standard deviations of standardised lake areas (used as an index of lake area sensitivity to short term climate fluctuations) were plotted against a climatic moisture index; the resulting scatter of points is constrained by a function relating lake sensitivity to long-term regional climatic moisture. The lakes show high sensitivity in the Grassland where potential évapotranspiration exceeds precipitation, a steep drop in sensitivity over a small range of climatic moisture values in the Aspen Parkland, and very low sensitivity in the Boreal Forest where precipitation exceeds potential évapotranspiration.
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Lyons, W. B., S. W. Tyler, R. A. Wharton, D. M. McKnight y B. H. Vaughn. "A Late Holocene desiccation of Lake Hoare and Lake Fryxell, McMurdo Dry Valleys, Antarctica". Antarctic Science 10, n.º 3 (septiembre de 1998): 247–56. http://dx.doi.org/10.1017/s0954102098000340.
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Stable isotope data from waters of lakes in the McMurdo Dry Valleys (MDV) of southern Victoria Land, Antarctica are presented in order to establish the climatic history of this region over the past two millennia. New data from Lake Fryxell and Lake Hoare in Toylor Valley, along with previously published data from Lake Vanda, Wright Valley and Lake Bonney, Taylor Valley are used to infer the recent climatic history of MDV. Lakes Vanda, Fryxell and Bonney appear to have lost their ice covers and evaporated to small, hypersaline ponds by 1000 to ~1200 yr BP. Lake Hoare either desiccated or did not exist prior to 1200 yr BP. These data indicate a major lowering of lake level prior to ~1000 yr BP, followed by a warmer and/or more humid climate since then.
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Davis, Bruce M. y Thomas N. Todd. "Competition between larval lake herring (Coregonus artedi) and lake whitefish (Coregonus clupeaformis) for zooplankton". Canadian Journal of Fisheries and Aquatic Sciences 55, n.º 5 (1 de mayo de 1998): 1140–48. http://dx.doi.org/10.1139/f98-004.
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Diet and growth of larval lake herring (Coregonus artedi) and lake whitefish (Coregonus clupeaformis) were compared in mesocosm experiments in a small mesotrophic lake in southeastern Michigan. Fish were sampled from single-species and mixed assemblages in 2-m3 cages for 8 weeks during April and May. Both species initially ate mostly cyclopoid copepodites and small cladocerans (Bosmina spp.). Schoener's index of diet overlap showed considerable overlap (70-90%). Lake whitefish ate Daphnia spp. and adult copepods about 2 weeks earlier than did lake herring, perhaps related to their larger mean mouth gape. Lake whitefish were consistently larger than lake herring until the eighth week, especially in the sympatric treatments. Lake whitefish appeared to have a negative effect on the growth of lake herring, as lake herring in mixed-species treatments were smaller and weighed less than lake herring reared in single-species treatments. The diet similarities of lake whitefish and lake herring larvae could make them competitors for food in the Great Lakes. The greater initial size of lake whitefish could allow them to eat larger prey earlier and thereby limit availability of these prey to lake herring at a crucial period of development.
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Gajewski, Konrad. "Modern and Holocene Pollen Assemblages from Some Small Arctic Lakes on Somerset Island, NWT, Canada". Quaternary Research 44, n.º 2 (septiembre de 1995): 228–36. http://dx.doi.org/10.1006/qres.1995.1067.
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AbstractModern pollen samples from 15 lakes along a north-south transect on western Somerset Island, NWT, Canada, show a decrease in pollen concentrations from the high arctic to the mid-arctic zone, but there are few differences in the pollen percentages between these sites. Long-distance transport accounts for up to 50% of the pollen in these lake sediments. Cores from two lakes show few changes in the percentages of important pollen types, except for an initial period, before 6000 yr B.P., of increased Salix. The pollen concentration of lake RS36 from the mid-arctic is twice that of lake RS29 from the high arctic, and at both sites the concentrations decreased during the past 6000 yr B.P. This suggests a climatic deterioration during the past 6000 yr which has caused a decrease in the abundance of plants on the landscape.
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Kosova, Anna L., Dmitrii B. Denisov y Svetlana B. Nikolaeva. "Diatom complexes from bottom sediments of small lakes of the Imandra depression". Issues of modern algology (Вопросы современной альгологии), n.º 2(20) (2019): 220–24. http://dx.doi.org/10.33624/2311-0147-2019-2(20)-220-224.
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The study of diatom complexes in the bottom sediments of 2 small nameless lakes on the western coast of Imandra Lake (Murmansk region) was carried out. The features of the historical dynamics of diatom flora in response to changes in the environment and climate in the Holocene are described. Diatom analysis revealed the effects of tectonic activity in the area of the Imandra Lake depression, accompanied by a sharp increase in the water level, which is confirmed by lithological data.
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Pileckas, Marijus, Tauras Alekna y Vaidotas Valskys. "Morphometry of Gelionys and Žaliasis Lakes". Geografija ir edukacija mokslo almanachas / Geography and Education Science Almanac, n.º 9 (22 de septiembre de 2021): 69–86. http://dx.doi.org/10.5200/ge.2021.4.
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Bathymetric surveys of Gelionys and Žaliasis Lakes (located in the Baltic Uplands, Aukštadvaris Regional Park, Lithuania) were carried out on April 21, 2020, from a boat with attached Lowrance HDI SKIMMER XDCR transducer (200 kHz), Simrad GO5 chartplotter and Lowrance Point-1 GPS/Glonass receiver. At the same time, the shorelines of the lakes were revised. Average distance between profiles was ~10 m and depth measurement accuracy up to 2–5 cm. Accuracy of water surface elevation measurement using GNSS receiver Topcon Hiper SR up to 1–2 cm. Later, detailed (0.5 × 0.5 m) digital lake bottom models (DEM) were developed, bathymetric plans of the lakes were created, the main morphometric features were calculated, the boundaries and area of the lake catchments were defined, and the physical-geographical characteristics of the lakes were described based on field observations and various data. Gelionys and Žaliasis are small lakes of glaciokarst origin. Gelionys Lake is oval-shaped while shape of Žaliasis Lake is closer to the circle. Despite small surface area the lakes are quite deep. According to survey data, the surface area of Gelionys Lake is 4.79 ha, water surface elevation 216.1 m a.s.l., maximum depth 19.8 m, mean depth 6.0 m, volume 288.3 thousands m3, catchment area 71 ha. The surface area of Žaliasis Lake is 2.14 ha, water surface elevation 120.9 m a.s.l., maximum depth 15.84 m, mean depth 5.7 m, volume 122.2 thousands m3, catchment area 60 ha. During the observation period (from May of 2018 to September of 2020), the annual amplitude of water level fluctuations in Gelionys Lake reached up to 0.47 m, and in Žaliasis Lake up to 0.33 m. Keywords: Gelionys, Žaliasis, glaciokarst, lake, bathymetric chart, morphometry, Lithuania, Aukštadvaris Regional Park.
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Rahel, Frank J. "Biogeographic Influences on Fish Species Composition of Northern Wisconsin Lakes with Applications for Lake Acidification Studies". Canadian Journal of Fisheries and Aquatic Sciences 43, n.º 1 (1 de enero de 1986): 124–34. http://dx.doi.org/10.1139/f86-013.
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Species–area relations, used to predict the number of fish populations lost in acidified lakes, may overestimate the number of extinctions if regression equations developed from unacidified (high-alkalinity) lakes are used to predict the number of species previously present in acidified (low-alkalinity) lakes. In 100 northern Wisconsin lakes, the species–area regression for alkaline lakes (>10 mg/L as CaCO3) had a higher intercept and greater slope than the regression for low-alkalinity, but unacidified lakes. Thus, low-alkalinity lakes had fewer species than alkaline lakes, and added species at a slower rate as lake size increased. Biogeographic factors (lake size, alkalinity, isolation from other water bodies) strongly influenced fish community composition. Small lake size appeared to exclude species requiring wave-washed, rocky substrates and species preferring cool, well-oxygenated water; such habitat is limited in small lakes. Low alkalinity and associated chemical conditions (e.g. low pH) limited the occurrence of many cyprinids and some percids (genus Etheostoma). Lake isolation (no inlet and outlet streams) appeared to have a limited effect on species composition. An exception was the reduced occurrence, in lakes without tributary streams, of species that spawn in flowing water. Fish distributions among Wisconsin lakes provide a test of habitat requirements proposed for other geographic regions.