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Rodriguez, Yarice, David A. R. Kristovich e Mark R. Hjelmfelt. "Lake-to-Lake Cloud Bands: Frequencies and Locations". Monthly Weather Review 135, n.º 12 (1 de dezembro de 2007): 4202–13. http://dx.doi.org/10.1175/2007mwr1960.1.
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Abstract Premodification of the atmosphere by upwind lakes is known to influence lake-effect snowstorm intensity and locations over downwind lakes. This study highlights perhaps the most visible manifestation of the link between convection over two or more of the Great Lakes lake-to-lake (L2L) cloud bands. Emphasis is placed on L2L cloud bands observed in high-resolution satellite imagery on 2 December 2003. These L2L cloud bands developed over Lake Superior and were modified as they passed over Lakes Michigan and Erie and intervening land areas. This event is put into a longer-term context through documentation of the frequency with which lake-effect and, particularly, L2L cloud bands occurred over a 5-yr time period over different areas of the Great Lakes region.
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Sikder, Md Safat, Jida Wang, George H. Allen, Yongwei Sheng, Dai Yamazaki, Chunqiao Song, Meng Ding, Jean-François Crétaux e Tamlin M. Pavelsky. "Lake-TopoCat: a global lake drainage topology and catchment database". Earth System Science Data 15, n.º 8 (8 de agosto de 2023): 3483–511. http://dx.doi.org/10.5194/essd-15-3483-2023.
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Abstract. Lakes and reservoirs are ubiquitous across global landscapes, functioning as the largest repository of liquid surface freshwater, hotspots of carbon cycling, and sentinels of climate change. Although typically considered lentic (hydrologically stationary) environments, lakes are an integral part of global drainage networks. Through perennial and intermittent hydrological connections, lakes often interact with each other, and these connections actively affect water mass, quality, and energy balances in both lacustrine and fluvial systems. Deciphering how global lakes are hydrologically interconnected (or the so-called “lake drainage topology”) is not only important for lake change attribution but also increasingly critical for discharge, sediment, and carbon modeling. Despite the proliferation of river hydrography data, lakes remain poorly represented in routing models, partially because there has been no global-scale hydrography dataset tailored to lake drainage basins and networks. Here, we introduce the global Lake drainage Topology and Catchment database (Lake-TopoCat), which reveals detailed lake hydrography information with careful consideration of possible multifurcation. Lake-TopoCat contains the outlet(s) and catchment(s) of each lake; the interconnecting reaches among lakes; and a wide suite of attributes depicting lake drainage topology such as upstream and downstream relationship, drainage distance between lakes, and a priori drainage type and connectivity with river networks. Using the HydroLAKES v1.0 (Messager et al., 2016) global lake mask, Lake-TopoCat identifies ∼ 1.46 million outlets for ∼ 1.43 million lakes larger than 10 ha and delineates 77.5×106 km2 of lake catchments covering 57 % of the Earth's landmass except Antarctica. The global lakes are interconnected by ∼ 3 million reaches, derived from MERIT Hydro v1.0.1 (Yamazaki et al., 2019), stretching a total distance of ∼10×106 km, of which ∼ 80 % are shorter than 10 km. With such unprecedented lake hydrography details, Lake-TopoCat contributes towards a globally coupled lake–river routing model. It may also facilitate a variety of limnological applications such as attributing water quality from lake scale to basin scale, tracing inter-lake fish migration due to changing climate, monitoring fluvial–lacustrine connectivity, and improving estimates of terrestrial carbon fluxes. Lake-TopoCat is freely accessible at https://doi.org/10.5281/zenodo.7916729 (Sikder et al., 2023).
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Sellers, Todd J., Brian R. Parker, David W. Schindler e 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 janeiro 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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Cengiz, Taner. "Periodic structures of Great Lakes levels using wavelet analysis". Journal of Hydrology and Hydromechanics 59, n.º 1 (1 de março de 2011): 24–35. http://dx.doi.org/10.2478/v10098-011-0002-z.
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Periodic structures of Great Lakes levels using wavelet analysisThe recently advanced approach of wavelet transforms is applied to the analysis of lake levels. The aim of this study is to investigate the variability of lake levels in four lakes in the Great Lakes region where the method of continuous wavelet transform and global spectra are used. The analysis of lake-level variations in the time-scale domain incorporates the method of continuous wavelet transform and the global spectrum. Four lake levels, Lake Erie, Lake Michigan, Lake Ontario, and Lake Superior in the Great Lakes region were selected for the analysis. Monthly lake level records at selected locations were analyzed by wavelet transform for the period 1919 to 2004. The periodic structures of the Great Lakes levels revealed a spectrum between the 1-year and 43- year scale level. It is found that major lake levels periodicities are generally the annual cycle. Lake Michigan levels show different periodicities from Lake Erie and Lake Superior and Lake Ontario levels. Lake Michigan showed generally long-term (more than 10 years) periodicities. It was shown that the Michigan Lake shows much stronger influences of inter-annual atmospheric variability than the other three lakes. The other result was that some interesting correlations between global spectrums of the lake levels from the same climatic region were found.
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Yan, Norman D., Warren I. Dunlop, Trevor W. Pawson e Lori E. MacKay. "Bythotrephes cederstroemi (Schoedler) in Muskoka Lakes: First Records of the European Invader in Inland Lakes in Canada". Canadian Journal of Fisheries and Aquatic Sciences 49, n.º 2 (1 de fevereiro de 1992): 422–26. http://dx.doi.org/10.1139/f92-048.
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The large predaceous European zooplankter Bythotrephes cederstroemi is now present in eight large recreational lakes in south-central Ontario, Canada: Lake Muskoka, Lake Joseph, Lake Rosseau, Fairy Lake, Mary Lake, Peninsula Lake, Lake Vernon, and Go Home Lake. These observations represent the first evidence that B. cederstroemi has invaded inland lakes in Canada, and we suggest that close monitoring is now needed to establish whether or not pelagic food webs of the lakes will respond.
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Laird, Neil, Ryan Sobash e Natasha Hodas. "The Frequency and Characteristics of Lake-Effect Precipitation Events Associated with the New York State Finger Lakes". Journal of Applied Meteorology and Climatology 48, n.º 4 (1 de abril de 2009): 873–86. http://dx.doi.org/10.1175/2008jamc2054.1.
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Abstract This study presents a climatological analysis of the frequency and characteristics of lake-effect precipitation events that were initiated or enhanced by lakes within the New York State (NYS) Finger Lakes region for the 11 winters (October–March) from 1995/96 through 2005/06. Weather Surveillance Radar-1988 Doppler (WSR-88D) data from Binghamton, New York, were used to identify 125 lake-effect events. Events occurred as 1) a well-defined, isolated precipitation band over and downwind of a lake, 2) an enhancement of mesoscale lake-effect precipitation originating from Lake Ontario and extending southward over an individual Finger Lake, 3) a quasi-stationary mesoscale precipitation band positioned over a lake embedded within extensive regional precipitation from a synoptic weather system, or 4) a transition from one type to another. Results show that lake-effect precipitation routinely develops over lakes that are considerably smaller than lakes previously discussed as being associated with lake-effect precipitation, such as the Great Lakes. Lake-effect events occurred during each month (October–March) across the 11 winters studied and were identified in association with each of the six easternmost Finger Lakes examined in this study. The frequency of NYS Finger Lakes lake-effect events determined in the current investigation paired with subsequent analyses of the environmental conditions leading to these events will allow for 1) comparative analyses of necessary conditions for lake-effect development across a range of lake sizes (e.g., NYS Finger Lakes, Lake Champlain, Great Salt Lake, and Great Lakes) and 2) an informative examination of the connection between mesoscale processes and climate variability.
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Lara, Mark Jason, e Melissa Lynn Chipman. "Periglacial Lake Origin Influences the Likelihood of Lake Drainage in Northern Alaska". Remote Sensing 13, n.º 5 (25 de fevereiro 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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Perales, K. Martin, Catherine L. Hein, Noah R. Lottig e M. Jake Vander Zanden. "Lake water level response to drought in a lake-rich region explained by lake and landscape characteristics". Canadian Journal of Fisheries and Aquatic Sciences 77, n.º 11 (novembro de 2020): 1836–45. http://dx.doi.org/10.1139/cjfas-2019-0270.
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Climate change is altering hydrologic regimes, with implications for lake water levels. While lakes within lake districts experience the same climate, lakes may exhibit differential climate vulnerability regarding water level response to drought. We took advantage of a recent drought (∼2005–2010) and estimated changes in lake area, water level, and shoreline position on 47 lakes in northern Wisconsin using high-resolution orthoimagery and hypsographic curves. We developed a model predicting water level response to drought to identify characteristics of the most vulnerable lakes in the region, which indicated that low-conductivity seepage lakes found high in the landscape, with little surrounding wetland and highly permeable soils, showed the greatest water level declines. To explore potential changes in the littoral zone, we estimated coarse woody habitat (CWH) loss during the drought and found that drainage lakes lost 0.8% CWH while seepage lakes were disproportionately impacted, with a mean loss of 40% CWH. Characterizing how lakes and lake districts respond to drought will further our understanding of how climate change may alter lake ecology via water level fluctuations.
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Zhang, Ao, Xinwen Zhao, Jun He, Xuan Huang, Xingyuezi Zhao e Yongbo Zhao. "Characteristics of Hydrogen and Oxygen Isotope Composition in Precipitation, Rivers, and Lakes in Wuhan and the Ecological Environmental Effects of Lakes". Water 15, n.º 16 (19 de agosto de 2023): 2996. http://dx.doi.org/10.3390/w15162996.
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Wuhan has a dense network of rivers and lakes. Due to the city’s development, the water system has been fragmented, the degradation of lakes is becoming increasingly severe, and the eco-environment has been significantly damaged. By collecting samples of the central surface water bodies in Wuhan, including Yangtze River water, Han River water, lake water, and precipitation, and by utilizing hydrogen and oxygen isotopes and multivariate statistical methods, the hydraulic connectivity and ecological environmental effects between the Yangtze River, the Han River, and the lakes were revealed. The results indicated the following: (1) The local meteoric water Line (LMWL) in the Wuhan area was δD = 7.47δ18O + 1.77. The river water line equation was approximately parallel to the atmospheric precipitation line in the Wuhan area. The intercept and slope of the lake waterline equation were significantly smaller. The enrichment degree of δ18O and δD was Yangtze River < Hanjiang River < lake water. (2) The cluster analysis showed that the lakes could be divided into two types, i.e., inner-flow degraded (IFD) lakes and outer-flow ecological (OFE) lakes. Urban expansion has resulted in fragmentation of the IFD lakes, changing the connectivity between rivers and lakes and weakening the exchange of water bodies between the Yangtze River and lakes. Simultaneously, evaporation has caused hydrogen and oxygen isotope fractionation, resulting in the relative enrichment of isotopes. The IFD lakes included the Taizi Lake, Yehu Lake, and the Shenshan Lake. The OFE lakes and the Yangtze River were active, evaporation was weak, and the hydrogen and oxygen isotopes were relatively depleted, mainly including the Huangjia Lake, the East Lake, the Tangxun Lake, etc. (3) The excessive deuterium (d-excess) parameter values in the Yangtze River and the Han River water were positive. In contrast, the d values in the lakes were mainly negative. In the case of a weakened water cycle, the effect of evaporation enrichment on lake water δ18O and δD had a significant impact. It is suggested that the water system connection project of “North Taizi Lake-South Taizi Lake-Yangtze River” and the small lakes connecting to large lakes project of “Wild Lake-Shenshan Lake-Tangxun Lake” should be implemented in time to restore the water eco-environment.
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Jia, Junmei, Qiuwen Chen, Haidong Ren, Renjie Lu, Hui He e Peiwen Gu. "Phytoplankton Composition and Their Related Factors in Five Different Lakes in China: Implications for Lake Management". International Journal of Environmental Research and Public Health 19, n.º 5 (7 de março de 2022): 3135. http://dx.doi.org/10.3390/ijerph19053135.
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In this paper, two trophic lakes: Lake Taihu and Lake Yanghe, and three alpine lakes: Lake Qinghai, Lake Keluke, and Lake Tuosu, were investigated to discover the connections between environmental factors and the phytoplankton community in lakes with differences in trophic levels and climatic conditions. Three seasonal data, including water quality and phytoplankton, were collected from the five lakes. The results demonstrated clear differences in water parameters and phytoplankton compositions in different lakes. The phytoplankton was dominated by Bacillariophyta, followed by Cyanobacteria and Chlorophyta in Lake Qinghai, Lake Keluke, and Lake Tuosu. It was dominated by Cyanobacteria (followed by Chlorophyta and Bacillariophyta in Lake Yanghe) and Cyanobacteria (followed by Chlorophyta and Cryptophyta in Lake Taihu). The temperature was an essential factor favoring the growth of Cyanobacteria, Chlorophyta, and Bacillariophyta, especially Cyanobacteria and Chlorophyta. The pH had significantly negative relationships with Cyanobacteria, Chlorophyta, and Bacillariophyta. Particularly, a high pH might be a strong and negative factor for phytoplankton growth in alpine lakes. A high salinity was also an adverse factor for phytoplankton. Those results could provide fundamental information about the phytoplankton community and their correlated factors in the alpine lakes of the Tibetan Plateau, contributing to the protection and management of alpine lakes.
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Donald, David B., e David J. Alger. "Geographic distribution, species displacement, and niche overlap for lake trout and bull trout in mountain lakes". Canadian Journal of Zoology 71, n.º 2 (1 de fevereiro de 1993): 238–47. http://dx.doi.org/10.1139/z93-034.
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Indigenous lacustrine populations of bull trout (Salvelinus confluentus) and lake trout (S. namaycush) are spatially separated within the southern part of the zone of distributional overlap (northern Montana, southwestern Alberta, and east-central British Columbia). In this area, lake trout occurred primarily in mountain lakes of 1032–1500 m elevation, while bull trout were found primarily in lakes between 1500 and 2200 m. Introductions of lake trout in the twentieth century and data obtained from beyond the study area indicated that both fishes can establish significant allopatric populations (more than 5% of the catch) in large, deep lakes (>8 ha in area and >8 m deep) over a wide elevation range. We tested the hypothesis that lake trout displace or exclude bull trout from lakes by determining the outcome of introductions of lake trout into two lakes that supported indigenous bull trout. Lake trout were introduced into Bow Lake in 1964, and by 1992 the bull trout population was decimated there and in another lake (Hector) situated 15 km downstream. Thus, lake trout can displace bull trout and may prevent bull trout from becoming established in certain low-elevation lakes. Population age-structure analyses also suggest that lake trout adversely affected bull trout. Bull trout populations in sympatry with lake trout, including the one extirpated from Hector Lake, had few old fish (18% were more than 5 years old; N = 40 fish from three lakes) compared with allopatric populations (49% were more than 5 years old; N = 235 fish from seven lakes). Niche overlap and the potential for competition between the two char species were substantial. In lakes with trophic structure ranging from simple to complex, bull trout and lake trout fed on similar foods and had similar ecological efficiencies (growth rates). Predation by lake trout on bull trout was not documented during the study.
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Wilcox, Evan J., Brent B. Wolfe e Philip Marsh. "Assessing the influence of lake and watershed attributes on snowmelt bypass at thermokarst lakes". Hydrology and Earth System Sciences 26, n.º 23 (9 de dezembro de 2022): 6185–205. http://dx.doi.org/10.5194/hess-26-6185-2022.
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Abstract. Snow represents the largest potential source of water for thermokarst lakes, but the runoff generated by snowmelt (freshet) can flow beneath lake ice and via the outlet without mixing with and replacing pre-snowmelt lake water. Although this phenomenon, called “snowmelt bypass”, is common in ice-covered lakes, it is unknown which lake and watershed properties cause variation in snowmelt bypass among lakes. Understanding the variability of snowmelt bypass is important because the amount of freshet that is mixed into a lake affects the hydrological and biogeochemical properties of the lake. To explore lake and watershed attributes that influence snowmelt bypass, we sampled 17 open-drainage thermokarst lakes for isotope analysis before and after snowmelt. Isotope data were used to estimate the amount of lake water replaced by freshet and to observe how the water sources of lakes changed in response to the freshet. Among the lakes, a median of 25.2 % of lake water was replaced by freshet, with values ranging widely from 5.2 % to 52.8 %. For every metre that lake depth increased, the portion of lake water replaced by freshet decreased by an average of 13 %, regardless of the size of the lake's watershed. The thickness of the freshet layer was not proportional to maximum lake depth, so that a relatively larger portion of pre-snowmelt lake water remained isolated in deeper lakes. We expect that a similar relationship between increasing lake depth and greater snowmelt bypass could be present at all ice-covered open-drainage lakes that are partially mixed during the freshet. The water source of freshet that was mixed into lakes was not exclusively snowmelt but a combination of snowmelt mixed with rain-sourced water that was released as the soil thawed after snowmelt. As climate warming increases rainfall and shrubification causes earlier snowmelt timing relative to lake ice melt, snowmelt bypass may become more prevalent, with the water remaining in thermokarst lakes post-freshet becoming increasingly rainfall sourced. However, if climate change causes lake levels to fall below the outlet level (i.e., lakes become closed-drainage), more freshet may be retained by thermokarst lakes as snowmelt bypass will not be able to occur until lakes reach their outlet level.
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Zhao, Zhilong, Zengzeng Hu, Jun Zhou, Ruliang Kan e Wangjun Li. "Response of Two Major Lakes in the Changtang National Nature Reserve, Tibetan Plateau to Climate and Anthropogenic Changes over the Past 50 Years". Land 12, n.º 2 (17 de janeiro de 2023): 267. http://dx.doi.org/10.3390/land12020267.
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Areal changes in alpine lakes on the Tibetan Plateau (TP) are reliable indicators of climate change and anthropogenic disturbance. This study used long-term Landsat images and meteorological records to monitor the temporal evolution patterns of lakes within the Changtang National Nature Reserve between 1972 and 2021 and examine the climatic and anthropogenic impacts on lake area changes. The results revealed that the area of Lake LongmuCo and Lake Jiezechaqia significantly expanded by 12.81% and 12.88% from 1972 to 2021, respectively. After 1999, Lake LongmuCo and Lake Jiezechaqia entered into a period of rapid expansion. During 1972–2021, the annual mean temperature significantly increased at a rate of 0.05 °C/a, while the change in annual precipitation was not significant. The temperature change was a major contributor to the observed changes of Lake LongmuCo and Lake Jiezechaqia between 1972 and 2021, while human intervention also played a vital role during 2013–2021. The glaciers around these two lakes decreased by 21.81%, and the increase in water supply from warming-triggered glacier melting was a reason of expansion of Lake LongmuCo and Lake Jiezechaqia. The areas of the two artificial salt lakes affiliated with Lake LongmuCo and Lake Jiezechaqia were 0.24 km2 and 2.67 km2 in 2013 and rose to 0.51 km2 and 9.80 km2 in 2021, respectively. In particular, the continuous exploitations of salt lakes to extract lithium resources have retarded the rate of expansion of Lake LongmuCo and Lake Jiezechaqia. The dams constructed by industrial enterprises have blocked the expansion of Lake LongmuCo to the south. This paper sheds new light on the influences of recent human intervention and climatic variation on alpine lakes within the TP. Due to the importance of alpine lakes in the TP, we need more comprehensive and in-depth efforts to protect the lake ecosystems within the national nature reserves.
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Poikāne, Sandra, e Vita Līcīte. "LAKE MANAGEMENT:THEORY AND PRACTICE". Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 1 (20 de junho de 2001): 144. http://dx.doi.org/10.17770/etr2001vol1.1949.
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Latvian Environment Agency carry out complex monitoring of Kemeri National Park since 1995. At now 6 lakes are included in this monitoring programme: - 3 bog lakes - Akacis Melnezers and Lake Slokas, Lake Aklais; - shallow and overgrown lagoone lake Kanieris; - hypertrophic Lake Valgums with heavy anthropogenic impact. Lake management plan contains: - the description of the current state o f each lake; - the optimal or required lake for each lake (objectives of management); - factors which influence the lake, especially anthropogenic; action plan to achieve the objectives.
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Kristovich, David A. R., Luke Bard, Leslie Stoecker e Bart Geerts. "Influence of Lake Erie on a Lake Ontario Lake-Effect Snowstorm". Journal of Applied Meteorology and Climatology 57, n.º 9 (setembro de 2018): 2019–33. http://dx.doi.org/10.1175/jamc-d-17-0349.1.
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AbstractAnnual lake-effect snowstorms, which develop through surface buoyant instability and upward moisture transport from the Laurentian Great Lakes, lead to important local increases in snowfall to the south and east. Surface wind patterns during cold-air outbreaks often result in areas where the air is modified by more than one Great Lake. While it is known that boundary layer air that has crossed multiple lakes can produce particularly intense snow, few observations are available on the process by which this occurs. This study examines unique observations taken during the Ontario Winter Lake-effect Systems (OWLeS) field project to document the process by which Lake Erie influenced snowfall that was produced over Lake Ontario on 28 January 2014. During the event, lake-effect clouds and snow that developed over Lake Erie extended northeastward toward Lake Ontario. OWLeS and operational observations showed that the clouds from Lake Erie disappeared (and snow greatly decreased) as they approached the Lake Ontario shoreline. This clear-air zone was due to mesoscale subsidence, apparently due to the divergence of winds moving from land to the smoother lake surface. However, the influence of Lake Erie in producing a deeper lake-effect boundary layer, thicker clouds, increased turbulence magnitudes, and heavier snow was identified farther downwind over Lake Ontario. It is hypothesized that the combination of a low-stability, high-moisture boundary layer as well as convective eddies and limited snow particles crossing the mesoscale subsidence region locally enhanced the lake-effect system over Lake Ontario within the plume of air originating over Lake Erie.
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Layden, A., S. MacCallum e C. Merchant. "Determining lake surface water temperatures (LSWTs) worldwide using a tuned 1-dimensional lake model (<i>FLake</i>, v1)". Geoscientific Model Development Discussions 8, n.º 10 (8 de outubro de 2015): 8547–606. http://dx.doi.org/10.5194/gmdd-8-8547-2015.
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Abstract. FLake, a 1-dimensional freshwater lake model, is tuned for 244 globally distributed large lakes using lake surface water temperatures (LSWTs) derived from Along-Track Scanning Radiometers (ATSRs). The model, tuned using only 3 lake properties; lake depth, albedo (snow and ice) and light extinction co-efficient, substantially improves the measured biases in various features of the LSWT annual cycle, including the LSWTs of saline and high altitude lakes. The daily mean absolute differences (MAD) and the spread of differences (±2 standard deviations) across the trial seasonally ice covered lakes (lakes with a lake-mean LSWT remaining below 1 °C for part of the annual cycle) is reduced from 3.01± 2.25 °C (pre-tuning) to 0.84 ± 0.51 °C (post-tuning). For non-seasonally ice-covered trial lakes (lakes with a lake-mean LSWT remaining above 1 °C throughout its annual cycle), the average daily mean absolute difference (MAD) is reduced from 3.55 ± 3.20 °C to 0.96 ± 0.63 °C. The post tuning results for the trial lakes (35 lakes) are highly representative of the post tuning results of the 244 lakes. The sensitivity of the summer LSWTs of deeper lakes to changes in the timing of ice-off is demonstrated. The modelled summer LSWT response to changes in ice-off timing is found to be strongly affected by lake depth and latitude, explaining 0.50 (R2adj, p = 0.001) of the inter-lake variance in summer LSWTs. Lake depth alone explains 0.35 (p =0.003) of the variance. The tuning approach undertaken in this study, overcomes the obstacle of the lack of available lake characteristic information (snow and ice albedo and light extinction co-efficient) for individual lakes. Furthermore, the tuned values for lake depth, snow and ice albedo and light extinction co-efficient for the 244 lakes provide guidance for improving LSWTs modelling in FLake.
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Wen, Chao, Qingming Zhan, De Zhan, Huang Zhao e Chen Yang. "Spatiotemporal Evolution of Lakes under Rapid Urbanization: A Case Study in Wuhan, China". Water 13, n.º 9 (23 de abril de 2021): 1171. http://dx.doi.org/10.3390/w13091171.
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The impact of urbanization on lakes in the urban context has aroused continuous attention from the public. However, the long-term evolution of lakes in a certain megacity and the heterogeneity of the spatial relationship between related influencing factors and lake changes are rarely discussed. The evolution of 58 lakes in Wuhan, China from 1990 to 2019 was analyzed from three aspects of lake area, lake landscape, and lakefront ecology, respectively. The Multi-Scale Geographic Weighted Regression model (MGWR) was then used to analyze the impact of related influencing factors on lake area change. The investigation found that the total area of 58 lakes decreased by 15.3%. A worsening trend was found regarding lake landscape with the five landscape indexes of lakes dropping; in contrast, lakefront ecology saw a gradual recovery with variations in the remote sensing ecological index (RSEI) in the lakefront area. The MGWR regression results showed that, on the whole, the increase in Gross Domestic Product (GDP), RSEI in the lakefront area, precipitation, and humidity contributed to lake restoration. The growth of population and the proportion of impervious surface (IS) in the lakefront area had different effects on different lakes. Specifically, the increase in GDP and population in all downtown districts and two suburb districts promoted lake restoration (e.g., Wu Lake), while the increase in population in Jiangxia led to lake loss. The growth of RSEI in lakefront area promoted the restoration of most lakes. A higher proportion of IS in lakefront area normally resulted in more lake loss. However, in some cases, the growth of IS was caused by lake conservation, which contributed to lake restoration (e.g., Tangxun Lake). The study reveals the spatiotemporal evolution of multiple lakes in Wuhan and provides a useful reference for the government to formulate differentiated protection policies.
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Gao, Jing, Tandong Yao e Daniel Joswiak. "Variations of water stable isotopes (δ18O) in two lake basins, southern Tibetan Plateau". Annals of Glaciology 55, n.º 66 (2014): 97–104. http://dx.doi.org/10.3189/2014aog66a109.
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Abstractδ18O measurements based on systematic sampling and isotopic modeling have been adopted to study the controls of stable isotopes in lake water in two lake basins (lakes Yamdrok-tso and Puma Yum-tso) at two different elevations on the southern Tibetan Plateau. Temporally, δ18O values in precipitation and lake water display a seasonal fluctuation in both lakes. Spatially, δ18O values in the two lake basins increase by 10% from the termini of glaciers to the lake shores, by ∽1% from the lake shores to the lake center and by 0.4% from the water surface to depth in these lakes. The clear annual δ18O variations indicate that lake water mixes sufficiently in a short time. Model results show that glacial meltwater and surface lake-water temperature are not the dominant factors in the balance process of stable isotopes in lake water. Equilibrium δ18O values decrease by 0.8% for Yamdrok-tso lake and 0.6% for Puma Yum-tso lake when glacial meltwater contributions to these lakes shrink by 60%. δ18O ratios increase rapidly during the initial stages and take a longer time to approach the equilibrium value.
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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 novembro 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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Layden, Aisling, Stuart N. MacCallum e Christopher J. Merchant. "Determining lake surface water temperatures worldwide using a tuned one-dimensional lake model (<i>FLake</i>, v1)". Geoscientific Model Development 9, n.º 6 (15 de junho de 2016): 2167–89. http://dx.doi.org/10.5194/gmd-9-2167-2016.
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Abstract. A tuning method for FLake, a one-dimensional (1-D) freshwater lake model, is applied for the individual tuning of 244 globally distributed large lakes using observed lake surface water temperatures (LSWTs) derived from along-track scanning radiometers (ATSRs). The model, which was tuned using only three lake properties (lake depth, snow and ice albedo and light extinction coefficient), substantially improves the measured mean differences in various features of the LSWT annual cycle, including the LSWTs of saline and high altitude lakes, when compared to the observed LSWTs. Lakes whose lake-mean LSWT persists below 1 °C for part of the annual cycle are considered to be seasonally ice-covered. For trial seasonally ice-covered lakes (21 lakes), the daily mean and standard deviation (2σ) of absolute differences between the modelled and observed LSWTs are reduced from 3.07 °C ± 2.25 °C to 0.84 °C ± 0.51 °C by tuning the model. For all other trial lakes (14 non-ice-covered lakes), the improvement is from 3.55 °C ± 3.20 °C to 0.96 °C ± 0.63 °C. The post tuning results for the 35 trial lakes (21 seasonally ice-covered lakes and 14 non-ice-covered lakes) are highly representative of the post-tuning results of the 244 lakes. For the 21 seasonally ice-covered lakes, the modelled response of the summer LSWTs to changes in snow and ice albedo is found to be statistically related to lake depth and latitude, which together explain 0.50 (R2adj, p = 0.001) of the inter-lake variance in summer LSWTs. Lake depth alone explains 0.35 (p = 0.003) of the variance. Lake characteristic information (snow and ice albedo and light extinction coefficient) is not available for many lakes. The approach taken to tune the model, bypasses the need to acquire detailed lake characteristic values. Furthermore, the tuned values for lake depth, snow and ice albedo and light extinction coefficient for the 244 lakes provide some guidance on improving FLake LSWT modelling.
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Hassan, Tanveer Bhat, R. Arnold e R. M. Mishra. "Comparative Physico-Chemical Limnology of Two Lakes of Kashmir Himalaya". International Journal of Multicultural and Multireligious Understanding 5, n.º 2 (1 de abril de 2018): 128. http://dx.doi.org/10.18415/ijmmu.v5i2.111.
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In the present paper an effort has been made to evaluate the trophic status of two lakes viz; Dal Lake and Manasbal Lake on the basis of physico-chemical parameters criterion. Four ecologically different habitats in each lake were selected for the present study i.e DL1-DL4 & MS1-MS4 in Dal and Manasbal Lake respectively. The rate of pollution in both the lakes varied from basin to basin as well as lake to lake. It has been observed that both lakes are subjected to anthropogenic stress in the form of nutrient enrichment which changes the overall trophic status of both the lakes. However, the stress is more pronounced in Dal Lake as compared to Manasbal Lake which shows higher pollution levels as depicted by physico-chemical parameters. While the rural lake (Manasbal) is marching towards high trophic nature as a result of heavy influx of nutrients from the catchment area, the urban valley lake (Dal) operating under tremendous anthropogenic pressures receives heavy load of pollutants leading to its rapid trophic evolution in the form of eutrophication.
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Bergmaier, Philip T., e Bart Geerts. "Airborne Radar Observations of Lake-Effect Snowbands over the New York Finger Lakes". Monthly Weather Review 144, n.º 10 (outubro de 2016): 3895–914. http://dx.doi.org/10.1175/mwr-d-16-0103.1.
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The vast majority of lake-effect snow research throughout the years has focused on the North American Great Lakes since they are often associated with strong lake-effect events that produce heavy downstream snowfall. This study investigates a lake-effect snow event that instead occurred over two smaller lakes, the New York Finger Lakes, which are just O(5) km wide and O(50) km long. A pair of well-defined snowbands that formed over Seneca and Cayuga Lakes, the two largest of the Finger Lakes, were sampled from above by a vertically pointing Doppler radar and lidar on board the University of Wyoming King Air (UWKA). With typical widths matching the widths of the lakes, and depths of less than 1000 m, the long-lake-axis-parallel bands were actually quite intense for their size. For example, updrafts of 2–3 m s−1 or greater within the band cores were common, and reflectivity occasionally exceeded 5 dBZ. Airborne dual-Doppler data show that both bands were sometimes accompanied by a well-defined thermally driven secondary circulation. Lidar data reveal that the Cayuga Lake band contained significantly more liquid water than the band over Seneca Lake, which was composed mainly of ice. Dissipating lake-effect ice clouds, carried downstream from Lake Ontario toward Seneca Lake, likely seeded the emerging convection over Seneca Lake, resulting in an accelerated depletion of liquid in the Seneca Lake band via more efficient snow growth.
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Sogut, Erdinc, e Ali Farhadzadeh. "ALONGSHORE VARIABILITY OF COASTAL MORHODYNAMICS IN EASTERN LAKE ERIE DUE TO LOW FREQUENCY OSCILLATIONS OF LAKE LEVEL". Coastal Engineering Proceedings, n.º 36 (30 de dezembro de 2018): 23. http://dx.doi.org/10.9753/icce.v36.sediment.23.
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Lake Erie has the fourth largest surface area, shallowest water depth and smallest volume among the five Great Lakes in North America (NOAA). The dominant wind direction over Lake Erie’s is southwest-northeast, along the lake’s longitudinal axis. The atmospheric and water level data of the lake demonstrate that high wind and moving pressure systems can result in high storm surge of up to 3 m on the eastern end of the lake and significant drop in the water level at the western end of the lake Due to its shallow depth, such a water level gradient can trigger unique post-storm free water-level fluctuations or seiches in Lake Erie (Farhadzadeh, 2017). The morphodynamic implications of such low frequency oscillations are yet to be studied for the lake’s shorelines. Most of studies on the contributions of long waves to beach morphology changes focused on low frequency harmonics induced by short waves, e.g. infragravity waves, edge waves, etc., oscillations with periods of up to a few minutes. Wright and Short (1984) discussed the differences in hydrodynamic processes and relative contributions of various mechanisms to morphological changes of beaches of different states, i.e., reflective, dissipative or intermediate. They concluded that for reflective beaches, incident waves and subharmonic edge waves are dominant while for dissipative beaches currents associated with infragravity standing waves are dominant in nearshore areas. Russell (1993) stated that as low frequency wave energy increases toward a shoreline, the offshore-directed transport at low frequency can become more pronounced.
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Notaro, Michael, Azar Zarrin, Steve Vavrus e Val Bennington. "Simulation of Heavy Lake-Effect Snowstorms across the Great Lakes Basin by RegCM4: Synoptic Climatology and Variability*,+". Monthly Weather Review 141, n.º 6 (1 de junho de 2013): 1990–2014. http://dx.doi.org/10.1175/mwr-d-11-00369.1.
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Abstract A historical simulation (1976–2002) of the Abdus Salam International Centre for Theoretical Physics Regional Climate Model, version 4 (ICTP RegCM4), coupled to a one-dimensional lake model, is validated against observed lake ice cover and snowfall across the Great Lakes Basin. The model reproduces the broad temporal and spatial features of both variables in terms of spatial distribution, seasonal cycle, and interannual variability, including climatological characteristics of lake-effect snowfall, although the simulated ice cover is overly extensive largely due to the absence of lake circulations. A definition is introduced for identifying heavy lake-effect snowstorms in regional climate model output for all grid cells in the Great Lakes Basin, using criteria based on location, wind direction, lake ice cover, and snowfall. Simulated heavy lake-effect snowstorms occur most frequently downwind of the Great Lakes, particularly to the east of Lake Ontario and to the east and south of Lake Superior, and are most frequent in December–January. The mechanism for these events is attributed to an anticyclone over the central United States and related cold-air outbreak for areas downwind of Lakes Ontario and Erie, in contrast to a nearby cyclone over the Great Lakes Basin and associated cold front for areas downwind of Lakes Superior, Huron, and Michigan.
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Reheis, Marith. "Highest Pluvial-Lake Shorelines and Pleistocene Climate of the Western Great Basin". Quaternary Research 52, n.º 2 (setembro de 1999): 196–205. http://dx.doi.org/10.1006/qres.1999.2064.
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Shoreline altitudes of several pluvial lakes in the western Great Basin of North America record successively smaller lakes from the early to the late Pleistocene. This decrease in lake size indicates a long-term drying trend in the regional climate that is not seen in global marine oxygen-isotope records. At +70 m above its late Pleistocene shoreline, Lake Lahontan in the early middle Pleistocene submerged some basins previously thought to have been isolated. Other basins known to contain records of older pluvial lakes that exceeded late Pleistocene levels include Columbus-Fish Lake (Lake Columbus-Rennie), Kobeh-Diamond (Lakes Jonathan and Diamond), Newark, Long (Lake Hubbs), and Clover. Very high stands of some of these lakes probably triggered overflows of previously internally drained basins, adding to the size of Lake Lahontan. Simple calculations based on differences in lake area suggest that the highest levels of these pluvial lakes required a regional increase in effective moisture by a factor of 1.2 to 3 relative to late Pleistocene pluvial amounts (assuming that effective moisture is directly proportional to the hydrologic index, or lake area/tributary basin area). These previously unknown lake levels reflect significant changes in climate, tectonics, and (or) drainage-basin configurations, and could have facilitated migration of aquatic species in the Great Basin.
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Minns, Charles K., James E. Moore, Brian J. Shuter e Nicholas E. Mandrak. "A preliminary national analysis of some key characteristics of Canadian lakes". Canadian Journal of Fisheries and Aquatic Sciences 65, n.º 8 (agosto de 2008): 1763–78. http://dx.doi.org/10.1139/f08-110.
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Knowledge of Canada’s lakes is needed to manage environmental stresses. Lake inventory and lake feature databases were used to build a national impact assessment template and assess regional typology. There are ~910 400 lakes with area ≥ 0.1 km2(10 ha), 37% of the Earth’s total. Lake features (number of lakes by size class, maximum depth, mean–maximum depth ratio, Secchi depth, pH, and total dissolved solids) were modeled regionally by secondary watershed (SWS) using linear regression models. Lake trout ( Salvelinus namaycush ) occurrence was analyzed as a cofactor to highlight regional links between lake characteristics and aquatic biota. Significant (R2from 0.231 to 0.492) regional models were obtained using area or maximum depth, lake trout occurrence, and their cross products as covariates. Analyses of fitted SWS coefficients showed that ecozones were a better predictor of lake characteristics than primary watersheds. The national typology was consistent with previous regional assessments. The regional models were used to estimate the number, area, and volume of lake trout lakes by size class and ecozone. There are ~66 500 lake trout lakes covering ~3 510 000 km2primarily on Boreal and Taiga Shield areas. Regional lake resource models will enable national assessment of stresses such as climate change and invasive species.
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Eckley, C. S., C. J. Watras, H. Hintelmann, K. Morrison, A. D. Kent e O. Regnell. "Mercury methylation in the hypolimnetic waters of lakes with and without connection to wetlands in northern Wisconsin". Canadian Journal of Fisheries and Aquatic Sciences 62, n.º 2 (1 de fevereiro de 2005): 400–411. http://dx.doi.org/10.1139/f04-205.
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Rates of Hg methylation and demethylation were measured in anoxic hypolimnetic waters of two pristine Wisconsin lakes using stable isotopes of Hg as tracers. One of the lakes is a clear-water seepage lake situated in sandy terrain with minimal wetland influence. The other is a dark-water lake receiving channelized inputs from a relatively large terrestrial wetland. Methyl mercury (MeHg) accumulated in the anoxic hypolimnia of both lakes during summer stratification, reaching concentrations of 0.8 ng·L1 in the clear-water lake and 5 ng·L1 in the dark-water lake. The stable isotopic assays indicated that rate constants of Hg(II) methylation (Km) ranged from 0.01 to 0.04·day1 in the clear-water lake and from 0.01 to 0.09·day1 in the dark-water lake, depending on the depth stratum. On average, Km was threefold greater in the dark-water lake. Hypolimnetic demethylation rate constants (Kdm) averaged 0.03·day1 in the clear-water lake and 0.05·day1 in the dark-water lake. These methylation rates were sufficient to account for the observed accumulation of MeHg in hypolimnetic water during summer in both lakes. Despite substantial export of MeHg from the wetland to the dark-water lake, our study indicates that in-lake production and decomposition of MeHg dominated the MeHg cycle in both lakes.
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Wen, Lijuan, Chan Wang, Zhaoguo Li, Lin Zhao, Shihua Lyu, Matti Leppäranta, Georgiy Kirillin e Shiqiang Chen. "Thermal Responses of the Largest Freshwater Lake in the Tibetan Plateau and Its Nearby Saline Lake to Climate Change". Remote Sensing 14, n.º 8 (7 de abril de 2022): 1774. http://dx.doi.org/10.3390/rs14081774.
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There are thousands of lakes in the Tibetan Plateau (TP), and most are saline. However, little is known about the responses of TP lakes to climate change, especially saline ones. We investigated the thermal responses of the largest freshwater lake (Ngoring Lake) in the TP and its nearby small saline lake (Hajiang Salt Pond) to climate change using the improved lake scheme in the Community Land model (CLM4-LISSS), in which we primarily developed the salinity parameterizations previously evaluated in the Great Salt Lake in USA and further considered the effect of salinity on the temperature of the maximum density of saline water in the present study. The improved lake model with salinity parameterizations was first applied to a saline lake in the TP, where saline lakes make up the majority of water bodies. The CLM4-LISSS model could effectively simulate lake surface water temperature (LSWT), lake water temperature (LT) and ice thickness in Ngoring Lake. Additionally, the model including our salinity parameterizations significantly improved simulations of LSWT and LT in Hajiang Salt Pond, especially in winter. The LSWT of the two completely opposite lakes were warming in the simulations at a rate above 0.6 °C/decade. Meteorological forces were the main driving factor, with increasing downward longwave radiation, air temperature and air humidity, as well as weakening winds contributing to LSWT increase. Compared to a hypothetical shallow freshwater lake, the greater depth of Ngoring Lake made its surface warm faster, and salinity slightly accelerated the warming of Hajiang Salt Pond. Monthly mean LSWT differences between the two lakes were induced by salinity effects in cold periods and lake depth in the unfrozen period. In response to a warming climate, the LSWT in the ice-free Hajiang Salt Pond rapidly increased from January to April due to the warming climate, whereas the LSWT of Ngoring Lake increased faster in the first and last month of the ice-cover period due to later ice-on and earlier ice-off. This study will provide a useful tool for saline lakes in the TP and help deepen our knowledge about the responses of TP lakes, especially the saline lakes, to climate change, as well as response differences between freshwater and saline lakes and the reasons for these differences.
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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 março 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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Rouse, Wayne R., Peter D. Blanken, Normand Bussières, Anne E. Walker, Claire J. Oswald, William M. Schertzer e Christopher Spence. "An Investigation of the Thermal and Energy Balance Regimes of Great Slave and Great Bear Lakes". Journal of Hydrometeorology 9, n.º 6 (1 de dezembro de 2008): 1318–33. http://dx.doi.org/10.1175/2008jhm977.1.
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Abstract Great Slave Lake and Great Bear Lake have large surface areas, water volumes, and high latitudinal positions; are cold and deep; and are subject to short daylight periods in winter and long ones in summer. They are dissimilar hydrologically. Great Slave Lake is part of the Mackenzie Basin flowthrough system. Great Bear Lake is hydrologically isolated in its own relatively small drainage basin and all of its inflow and outflow derive from its immediate watershed. Great Slave Lake’s outflow into the Mackenzie River is more than 8 times that from Great Bear Lake. Input from the south via the Slave River provides 82% of this outflow volume. These hydrological differences exert pronounced effects on the thermodynamics, hydrodynamics, and surface climates of each lake. The quantitative results in this study are based on limited datasets from different years that are normalized to allow comparison between the two lakes. They indicate that both lakes have regional annual air temperatures within 2°C of one another, but Great Slave Lake exhibits a much longer open-water period with higher temperatures than Great Bear Lake. During the period when the lakes are warming, each lake exerts a substantial overlake atmospheric cooling, and in the period when the lakes are cooling, each exerts a strong overlake warming. This local cooling and warming cycle is greatest over Great Bear Lake. Temperature and humidity inversions are frequent early in the lake-warming season and very strong lapse gradients occur late in the lake-cooling season. Annually, for both lakes, early ice breakup is matched with late freeze-up. Conversely, late breakup is matched with early freeze-up. The magnitudes of midlake latent heat fluxes (evaporation) and sensible heat fluxes from Great Slave Lake are substantially larger than those from Great Bear Lake during their respective open-water periods. The hypothesis that because they are both large and deep, and are located in high latitudes, Great Slave Lake and Great Bear Lake will exhibit similar surface and near-surface climates that are typical of large lakes in the high latitudes proves invalid because their different hydrological systems impose very different thermodynamic regimes on the two lakes. Additionally, such an extensive north-flowing river system as the Mackenzie is subjected to latitudinally variable meteorological regimes that will differentially influence the hydrology and energy balance of these large lakes. Great Slave Lake is very responsive to climatic variability because of the relation between lake ice and absorbed solar radiation in the high sun season and we expect that Great Bear Lake will be affected in a similar fashion.
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Neumann, Klaus, W. Berry Lyons, John C. Priscu, David J. Desmarais e Kathleen A. Welch. "The carbon isotopic composition of dissolved inorganic carbon in perennially ice-covered Antarctic lakes: searching for a biogenic signature". Annals of Glaciology 39 (2004): 518–24. http://dx.doi.org/10.3189/172756404781814465.
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AbstractThe stable-isotopic signature of dissolved inorganic carbon (DIC) has been routinely used in temperate lake systems to investigate the biogeochemical dynamics of carbon. We studied seven perennially ice-covered lakes in the McMurdo Dry Valleys, Antarctica, to ascertain how carbon cycling affects the δ13C of DIC in water columns of these systems. Unlike temperate lakes and, in fact, most polar lake systems, the permanent ice covers of these lakes eliminate physical mixing (turnover) and hence redistribution of DIC in the lakes, as well as minimize CO2 exchange with the atmosphere. These important and unique physical constraints have significant impact on carbon dynamics in the lakes, and important consequences for the δ13C distribution. The geochemistry in these lakes is influenced in varying amounts by landscape position, hydrologic input and their evolutionary history. Five of these lakes (both lobes of Lake Bonney, and Lakes Fryxell, Miers and Vanda) have surface water δ13C ratios of 0–4‰, Lake Hoare has more negative values, while Lake Joyce, the highest-elevation lake, has a much higher value (10.5‰). All of the lakes have upper- to mid-depth δ13C maxima reflecting biological uptake of 12C. Only four of the lakes (Lakes Vanda, Joyce, Hoare and Fryxell) have deep waters with negative values of δ13C, implying rigorous remineralization of 12C at depth. Lake Miers, the only lake that is not closed basin, has the smallest δ13C variation with depth, indicating that hydrologic exchange greatly influences the δ13C signal.
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Wen, X., Z. Li, D. Xiang, S. Shen, D. Hu e X. Xiao. "INLAND-LAKES PROTECTION APPLICATION WITH HIGH RESOLUTION SATELLITE IMAGERY IN WUHAN CITY". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-7/W3 (30 de abril de 2015): 1025–28. http://dx.doi.org/10.5194/isprsarchives-xl-7-w3-1025-2015.
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The new data source of China’s civilian high resolution earth observation system ZY-3, GF-1 were applied in the application of the monitoring and protection of the inland-lakes in Wuhan, Hubei Province. After the pre-process of these high resolution satellite images, the object-oriented classification and object-oriented change detection technology were applied in the inland-lakes protection of Wuhan, China. In this paper, the Xiwanhu Lake and Tangxunhu Lake including their surrounding areas were selected as an example, with the experiments the status of these lakes including the lake boundary, lake area and the change of these lakes including the lake water surface increased area, lake water surface decreased area were be obtained. Compared with the pixel-based method, the object-oriented classification and change detection technology shows its intuitive and higher precision in inland-lake protection. Remote sensing technology should be applied in monitoring and protection the inland-lake and other respects of water resource management more widely and deeply in China.
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Trippel, Edward A., e F. William H. Beamish. "Multiple Trophic Level Structuring in Salvelinus–Coregonus Assemblages in Boreal Forest Lakes". Canadian Journal of Fisheries and Aquatic Sciences 50, n.º 7 (1 de julho de 1993): 1442–55. http://dx.doi.org/10.1139/f93-165.
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Hypolimnetic trophic interactions were examined among lake trout (Salvelinus namaycush), cisco (Coregonus artedi), zooplankton, and macroinvertebrates in six northwestern Ontario lakes varying sevenfold in conductivity. Faster growth and larger body size of lake trout in high-conductivity lakes were associated with larger meal sizes, earlier entry of cisco into their diet, and consumption of relatively few, large-bodied prey. Cisco preyed on zooplankton and macroinvertebrates. Cisco were abundant, large bodied, and fast growing in high-conductivity lakes. In one low-conductivity lake (Greenwich Lake), lake trout were 12 times as abundant as cisco whereas in all other lakes, lake trout to cisco ratios were ~ 1:1 or less regardless of conductivity. In Greenwich Lake, lake trout consumed large quantities of age-0 cisco and Mysis relicta, which was associated with "top-down" trophic structuring. Food web analyses strongly suggest that in Greenwich Lake the high abundance of piscivores resulted directly in a low abundance of planktivores and indirectly in a large-bodied zooplankton community and planktivores with rapid growth rates.
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Stanislavskaya, E. V., A. L. Afanas’eva e O. A. Pavlova. "Algoflora of lakes in the Kurgal’sky Nature reserve (Leningrad region)". Povolzhskiy Journal of Ecology, n.º 3 (23 de novembro de 2021): 335–47. http://dx.doi.org/10.35885/1684-7318-2021-3-335-347.
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Various algocenosises in the brackish Lake Lipovskoe and ultra-oligotrophic Lake Beloe located in the Kurgal’sky Nature reserve were studied in May and July of 2019. In the algal flora of the lakes studied, we found 291 taxa belonging to 9 orders. The both lakes were characterized by high species richness, namely: 179 and 181 algae taxa were identified in the Lake Lipovskoe and Lake Beloe, respectively. In the Lake Lipovskoe, its phytoplankton was dominated by Cyanophyta, Cryptophyta and Dinophyta, among which brackish-water and marine species were presented. In the periphyton of this Lake, brackish-water diatoms and green algae were the most abundant. In the Lake Beloe, its phytoplankton was dominated by Dinophyta, Bacillariophyta and Chlorophyta; the blue-greens, diatoms and green algae dominated in the periphyton of Lake Beloe. Despite that the lakes are located close to each other, their algal flora is quite different: the Sorensen similarity index between the two lakes was 38% only. The phytoplankton biomass in both lakes was low, increasing from spring to summer. In the Lake Lipovskoe, the phytoplankton biomass varied from 0.45 to 1.9 mg/L, chlorophyll a fluctuated from 3.9 to 7.1 µg/L. In the Lake Beloe, the phytoplankton biomass varied from 0.3 to 1.4 mg/L, chlorophyll a fluctuated from 0.45 to 1.3 µg/L. The periphyton biomass was 20 g/m2 (chlorophyll a being 22 mg/m2 ) and 17 g/m2 (chlorophyll a being 17 mg/m2 ) in the Lake Lipovskoe and Lake Beloe, respectively. Nowadays, the ecological status of both lakes can be considered satisfactory, because based on trophic conditions and species compositions they belong to waterbodies of clean and satisfactory clean conditions (II–III classes of water quality). To preserve the unique flora of the lakes in the Kurgal’sky Nature reserve, nature-protected measures should be strengthened.
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Aisyah, Siti, Sulastri Sulastri, Rahmi Dina e Mey Ristanti Widoretno. "Physical-Chemical Characteristic and Trophic Status of Some Small Lakes in Ciliwung Watershed, West Java Indonesia". Indonesian Journal of Limnology 2, n.º 2 (30 de dezembro de 2021): 1–8. http://dx.doi.org/10.51264/inajl.v2i2.15.
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Small lakes are important freshwater resources to support the quality of human life. However, small lakes in the watershed are becoming threatened ecosystems because of increasing land-use changes and anthropogenic activity. The study aimed to determine characteristic physical-chemical parameters and trophic status some small lake in Ciliwung Watershed to support the sustainable management of small lakes in the Ciliwung watershed in preventing eutrophication effects. The data was collected in April and June 2021. Measurement and analysis of water quality parameters were conducted by insitu and Laboratory. Some parameters were not in accordance with the Government Regulation number 22/2021 for class II water quality criteria (WQC), including TSS (>50 mg.L-1)., TP (>0.03 mg.L-1), COD (>25 mg.L-1) and DO (<3 mg.L-1), especially for Lake Sunter and Lake Cincin.There are two groups of lakes based on water quality and trophic status. Lake Telaga Warna Lake Cikaret, and Lake Cilodong were classified as eutrophic while lake Sunter and Lake Cincin were classified as hypereutrophic lake Lake Telaga Warna, Lake Cikaret, and Lake Cilodong, located at the upper and middle watershed, are eutrophic, characterized by deeper bottom and higher Secchi depth. At the lower watershed, Lake Sunter and Lake Cincin are hypereutrophic characterized by higher nutrients (TN and TP), COD, temperature, conductivity, salinity, and TDS. The downstream area was a densely populated area that contributed high pollution from upstream and middle of Ciliwung watershed.
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Miller, A., e David Snow. "Trophic Classification of Selected Lakes in Yellowstone National Park". UW National Parks Service Research Station Annual Reports 23 (1 de janeiro de 1999): 141–42. http://dx.doi.org/10.13001/uwnpsrc.1999.3393.
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The purpose of this study is to evaluate the trophic state of five lakes in southern Yellowstone National Park in order to determine if the human activity in the local area is having a negative environmental impact and possibly increasing the eutrophication rate. While some previous analyses have been done on these lakes, this study is intended to be a preliminary trophic state evaluation to which future analyses can be compared. The five lakes sampled are Shoshone Lake, Lewis Lake, Heart Lake, Riddle Lake, and Duck Lake. Each lake, with the exceptions of Riddle Lake and Duck Lake, was sampled at several locations. These samples were taken during the months of June through August of 1999 by Woodruff Miller and Dave Anderson of the BYU Civil & Environmental Engineering Department.
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Juutinen, S., M. Rantakari, P. Kortelainen, J. T. Huttunen, T. Larmola, J. Alm, J. Silvola e P. J. Martikainen. "Methane dynamics in different boreal lake types". Biogeosciences 6, n.º 2 (16 de fevereiro 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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Caroni, Rossana, Monica Pinardi, Gary Free, Daniela Stroppiana, Lorenzo Parigi, Giulio Tellina, Mariano Bresciani, Clément Albergel e Claudia Giardino. "Investigating the Impact of Wildfires on Lake Water Quality Using Earth Observation Satellites". Applied Sciences 14, n.º 6 (21 de março de 2024): 2626. http://dx.doi.org/10.3390/app14062626.
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A study was carried out to investigate the effects of wildfires on lake water quality using a source dataset of 2024 lakes worldwide, covering different lake types and ecological settings. Satellite-derived datasets (Lakes_cci and Fire_cci) were used and a Source Pathway Receptor approach applied which was conceptually represented by fires (burned area) as a source, precipitation/drought representing transport dynamics, and lakes as the ultimate receptor. This identified 106 lakes worldwide that are likely prone to be impacted by wildfires via a terrestrial pathway. Satellite-derived chlorophyll-a (Chl-a) and turbidity variables were used as indicators to detect changes in lake water quality potentially induced by wildfires over a four-year period. The lakes with the largest catchment areas burned and characterized by regular annual fires were located in Africa. Evidence for a strong influence of wildfires was not found across the dataset examined, although clearer responses were seen for some individual lakes. However, among the hydro-morphological characteristics examined, lake depth was found to be significant in determining Chl-a concentration peaks which were higher in shallow and lower in deep lakes. Lake turbidity responses indicated a dependence on lake catchment and weather conditions. While wildfires are likely to contribute to the nutrient load of lakes as found in previous studies, it is possible that in many cases it is not a dominant pressure and that its manifestation as a signal in lake Chl-a or turbidity values depends to a large part on lake typology and catchment characteristics. Assessment of lake water quality changes six months after a fire showed that Chl-a concentrations either increased, decreased, or showed no changes in a similar number of lakes, indicating that a lake specific ecological and hydro-morphological context is important for understanding lake responses to wildfires.
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Juutinen, S., M. Rantakari, P. Kortelainen, J. T. Huttunen, T. Larmola, J. Alm, J. Silvola e P. J. Martikainen. "Methane dynamics in different boreal\\newline lake types". Biogeosciences Discussions 5, n.º 4 (1 de setembro de 2008): 3457–96. http://dx.doi.org/10.5194/bgd-5-3457-2008.
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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 representatively in the boreal zone, 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. CH4 content in the hypolimnion was related to oxygen and nutrient concentrations, and lake depth or area. The surface water CH4 concentration was related to the depth or area of lake. Methane close to the bottom can be viewed as proxy of lake status in terms of frequency of anoxia and nutrient levels. Median CH4 release from randomly selected lakes was 45 mmol m−2 a−1. Shallow lakes had the highest median CH4 effluxes, with the clear shallow lake type having the smallest median. Our data, combined with other studies, suggest that lake surface area could be used for an approximation of CH4 release from lakes. Shallow small lakes common in boreal and arctic landscapes may have disproportional significance with respect to CH4 release.
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Zhou, Yan, Xiangbin Cui, Zhenxue Dai, Xiaobing Zhou, Lin Li, Su Jiang e Bo Sun. "The Antarctic Subglacial Hydrological Environment and International Drilling Projects: A Review". Water 16, n.º 8 (13 de abril de 2024): 1111. http://dx.doi.org/10.3390/w16081111.
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Subglacial lakes and hydrological systems play crucial roles in Antarctic subglacial hydrology, water balance, subglacial geomorphology, and ice dynamics. Satellite altimetry has revealed that some recurrent water exchange occurs in subglacial lakes. They are referred to as ’active lakes’, which prominently influence a majority of subglacial hydrological processes. Our analysis indicates that active subglacial lakes are more likely to be situated in regions with higher surface ice flow velocities. Nevertheless, the origin of subglacial lakes still remains enigmatic and uncertain. They could have potential associations with geothermal heat, ice sheets melting, and ice flow dynamics. Subglacial lake drilling and water sampling have the potential to provide valuable insights into the origin of subglacial lakes and subglacial hydrological processes. Moreover, they could also offer unique opportunities for the exploration of subglacial microbiology, evolution of the Antarctic ice sheets, and various fundamental scientific inquiries. To date, successful drilling and sampling has been accomplished in Lake Vostok, Lake Mercer, and Lake Whillans. However, the use of drilling fluids caused the water sample contamination in Lake Vostok, and the drilling attempt at Lake Ellsworth failed due to technical issues. To explore more of the conditions of the Antarctic subglacial lakes, the Lake Centro de Estudios Científicos (Lake CECs) and Lake Snow Eagle (LSE) drilling projects are upcoming and in preparation. In this study, we aim to address the following: (1) introduce various aspects of Antarctic subglacial lakes, subglacial hydrological elements, subglacial hydrology, and the interactions between ice sheets and the ocean; and (2) provide an overview and outlook of subglacial lakes drilling projects.
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Liu, Yuting, Zhaoxia Ye, Qiaoyun Jia, Aynur Mamat e Hanxiao Guan. "Multi-Source Remote Sensing Data for Lake Change Detection in Xinjiang, China". Atmosphere 13, n.º 5 (29 de abril de 2022): 713. http://dx.doi.org/10.3390/atmos13050713.
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Lake water resources in arid areas play an important role in regional resource and environmental management. Therefore, to master the dynamic changes in lake water resources in arid areas, the laser altimetry satellite and land resource satellite were used to interpret the changes in water level and the areas of alpine lakes and non-alpine lakes. The dynamic changes in the lake and their relationship with glacial meltwater, precipitation, and runoff of the lake basin were analyzed using the unary linear regression equation, the ratio of glacier area to lake area (G–L ratio), and the ratio of lake basin area to lake area (supply coefficient). The results were as follows: the changes in alpine lakes were closely related to the supply coefficient (basin/lake area ratio) but weakly related to the G–L ratio (glacier/lake area ratio). In addition, the spatial pattern of lake change was consistent with that of climate change. There was a strong correlation between the lake, precipitation, and temperature during the snowmelt period. Thus, it can be seen that the changes in the lake were caused by precipitation, glacial melt, snowmelt, and other multi-factors. Therefore, this study on the changes in water resources in different types of lakes and their influencing factors provides data support for water resources managers to evaluate the health and sustainable utilization of the ecological environment.
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Patalas, K., e 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 dezembro 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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Cao, Yang, Congsheng Fu, Mingxiang Yang, Huawu Wu, Haohao Wu, Haixia Zhang, Ye Xia e Zichun Zhu. "Exploring the Drivers for Changes in Lake Area in a Typical Arid Region during Past Decades". Water 15, n.º 19 (24 de setembro de 2023): 3354. http://dx.doi.org/10.3390/w15193354.
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Lakes are important surface water bodies, and ongoing climate change is a growing threat to the hydrological cycle and water resource availability of lakes in arid regions. Accurately estimating different drivers’ contributions to lake water volume can enhance our understanding of lake variations in arid regions. In this study, we combined the land surface model and hydrological model, as well as statistical methods, to analyze the spatiotemporal heterogeneity of lake area changes and the factors affecting these changes during the past decades in Bosten Lake, Ulungur Lake, Ebinur Lake, and Sayram Lake, which are located in a typical dry region in China. The study revealed that the average amounts of river inflow, TWVF, lake ice sublimation, lake surface precipitation, and river outflow in the four lakes were 17.41 × 108 m3 yr−1, 6.60 × 108 m3 yr−1, 0.41 × 108 m3 yr−1, 0.98 × 108 m3 yr−1, and 9.12 × 108 m3 yr−1, respectively. We found that river inflow is the dominant factor affecting changes in open lake areas, while lake surface precipitation is the main factor affecting changes in closed lake areas. Our findings suggest that the main factors dominating the variability of lake water volume differ in different phases and lake types.
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Torbick, Nathan, Beth Ziniti, Shuang Wu e Ernst Linder. "Spatiotemporal Lake Skin Summer Temperature Trends in the Northeast United States". Earth Interactions 20, n.º 25 (1 de dezembro de 2016): 1–21. http://dx.doi.org/10.1175/ei-d-16-0015.1.
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Abstract Lakes have been suggested as an indicator of climate change; however, long-term, systematic records of lake temperature are limited. Satellite remote sensing is capable of supporting lake temperature mapping with the advantage of large-area and systematic observations. The goal of this research application was to assess spatiotemporal trends in lake skin temperature for all lakes over 8 ha across northern New England for the past three decades. Nearly 10 000 Landsat scenes for July, August, and September from 1984 to 2014 were processed using MODTRAN and MERRA parameterizations to generate atmospherically corrected lake skin temperature records. Results show, on average, lakes warmed at a rate of 0.8°C decade−1, with smaller lakes warming at a faster rate. Complementing regression and space–time analyses showed similar results (R2 = 0.63) for lake temperature trends and found lakes, on average, are warming faster than daily maximum or minimum air temperature. No major hot spots were found as lake temperature changes were heterogeneous on a local scale and evenly distributed across the region. Maximum and minimum daily temperature, lake size, and elevation were found as significant drivers of lake temperature. This effort provides the first regionally focused and comprehensive spatiotemporal assessment of thousands (n = 3955) of lakes concentrated in one geographic region. The approach is scalable and adaptable to any region for assessing lake temperature trends and potential drivers.
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Ławniczak, Agnieszka. "Overgrowing of two polymictic lakes in Central-Western Poland". Limnological Review 10, n.º 3-4 (1 de janeiro de 2010): 147–56. http://dx.doi.org/10.2478/v10194-011-0017-1.
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Overgrowing of two polymictic lakes in Central-Western PolandThis study examined the overgrowth in two eutrophic lakes during the period 1961-2008. In addition, for comparative studies, analyses of plant community structures in these lakes were performed to assess the effects of human pressure, such as water level reduction and increase of nutrient availability on changes in the range of the littoral zone surface. To achieve these aims aerial photos, ortophotmaps, GPS measurements were used to evaluate changes in plant cover in two lakes: Niepruszewskie and Tomickie. Considerable differences between the studied lakes located in an agricultural catchment were observed. Lake Niepruszewskie was characterised by a threefold higher rate of overgrowing, measured per hectare, in comparison with Lake Tomickie. Moreover, in comparison with lake areas, rates of overgrowing were substantialy higher in Lake Tomickie than Lake Niepruszewskie, which is almost seven times bigger. The littoral zones of both lakes are dominated by emergent vegetation. Compared to the data from 1961, the zone of Lake Niepruszewskie increased almost threefold. The biggest changes in overgrowing were observed after reduction of water level (>2002) which was 1.30 ha yr-1. During almost 50 years, emergent vegetation in Lake Tomickie increased more than fivefold. The most intensive growth was observed in years from 1961 to 1986, which amounted to 0.73 ha yr-1. Probably, water level reductions in Lake Niepruszewskie and high eutrophication in Lake Tomickie were recognised as major factors causing intensive overgrowing in the studied lakes.
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Baťka, Jan, Vít Vilímek, Eva Štefanová, Simon J. Cook e Adam Emmer. "Glacial Lake Outburst Floods (GLOFs) in the Cordillera Huayhuash, Peru: Historic Events and Current Susceptibility". Water 12, n.º 10 (23 de setembro de 2020): 2664. http://dx.doi.org/10.3390/w12102664.
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The aim of this paper is to create a glacial lake inventory for the Cordillera Huayhuash in Peru and to evaluate the susceptibility of lakes to the generation of glacial lake outburst floods (GLOFs). Using high-resolution satellite images, we undertook qualitative and quantitative analysis of lake type, characteristics and distribution, and placed our findings within the context of existing Peru-wide lake inventories. We also mapped and analyzed past GLOFs, revealing a total of 10 GLOFs and 4 ambiguous events, most of which have not been reported before. We found that past GLOFs usually occurred as a result of moraine dam breach during the proglacial stage of lake evolution. Further, we used our lake inventory to evaluate GLOF susceptibility of all lakes larger than 20,000 m2. Of 46 evaluated lakes, only two lakes (Lake Tsacra and Lake W014) are currently susceptible to generating a GLOF, which would most likely be through dam overtopping resulting from a flood originating in smaller lakes located upstream. The future perspectives of lake evolution and implications for GLOF hazard management are discussed in light of the post-Little Ice Age glacier ice loss as well as in the context of extensive related research undertaken in the nearby Cordillera Blanca.
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Lv, Aifeng, e Chuanhui Zhang. "Analysis of the Characteristics and Driving Forces of Changes in Lake Water Volume in Inland Arid Basins in China". Water 14, n.º 19 (5 de outubro de 2022): 3141. http://dx.doi.org/10.3390/w14193141.
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Lakes are sensitive indicators of climatic change and are important resources for regional economic development. In recent years, there have been many studies related to the changes in lake area and lake volume. However, further studies are still required to understand the responses of lakes to climatic change and human activities. This paper utilizes lakes in the Qaidam Basin, an inland arid region of China, as the object of study and investigates the characteristics of variability in lake changes and its driving forces by combining multi-source remote sensing, model simulations and historical data. We first analyzed the spatiotemporal pattern of climatic change in the basin under the background of global warming. The response of lake water volume to climatic change and human activities is then discussed. Finally, the main factors that affect the change in lake water volume in different regions of the basin are delineated. The water volume of lakes in the Qaidam Basin increased by 3.81 km3 from 1990 to 2020. Particularly since the 21st century, the water volume of lakes has increased rapidly, and an increasingly abrupt change appeared around 2015. The increases in precipitation and vegetation area are the main and secondary factors that led to the increase in total lake water volume in the basin, respectively. However, the main influencing factors still vary in different regions. The impact of air temperature, evaporation, and changes in the cropland area on the change in lake water volume is generally not obvious. Human activities, such as the development of salt lakes and damming, have led to substantial changes in the spatial pattern of lakes in the middle of the basin and are associated with the replacement, genesis, and disappearance of Yiliping Lake, Yahu Lake and West Taijinar Lake, respectively. This study reveals the changing characteristics of climate and lake water volume in inland arid basins in China, which are highly important to understand the responses of lakes to climatic change and human activities, and provides a scientific basis for the rational development and utilization of lake resources in arid basins.
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Li, Bei, Yi-Chi Zhang, Ping Wang, Chao-Yang Du e Jing-Jie Yu. "Estimating Dynamics of Terminal Lakes in the Second Largest Endorheic River Basin of Northwestern China from 2000 to 2017 with Landsat Imagery". Remote Sensing 11, n.º 10 (15 de maio de 2019): 1164. http://dx.doi.org/10.3390/rs11101164.
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Quantifying terminal-lake dynamics is crucial for understanding water-ecosystem-economy relationship across endorheic river basins in arid environments. In this study, the spatio-temporal variations in terminal lakes of the lower Heihe River Basin were investigated for the first time since the Ecological Water Diversion Project commenced in 2000. The lake area and corresponding water consumption were determined with 248 Landsat images. Vital recovery of lakes occurred two years after the implementation of the project, and the total lake area increased by 382.6%, from 30.7 to 148.2 km2, during 2002–2017. East Juyan Lake (EJL) was first restored as a project target and subsequently reached a maximum area of 70.1 km2. Water dispersion was initiated in 2003, with the East river prioritized for restoration. Swan Lake in the East river enlarged to 67.7 km2 by 2017, while the other four lakes temporarily existed or maintained an area < 7 km2, such as West Juyan Lake. Water consumed by lakes increased synchronously with lake area. The average water consumption of the six lakes was 1.03 × 108 m3/year, with 63% from EJL. The increasing terminal lakes; however, highlight the seasonal competition for water use between riparian vegetation and lake ecosystems in water-limited areas.
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Zhao, Zhilong, Yue Zhang, Zengzeng Hu e Xuanhua Nie. "Contrasting Evolution Patterns of Endorheic and Exorheic Lakes on the Central Tibetan Plateau and Climate Cause Analysis during 1988–2017". Water 13, n.º 14 (17 de julho de 2021): 1962. http://dx.doi.org/10.3390/w13141962.
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The alpine lakes on the Tibetan Plateau (TP) are indicators of climate change. The assessment of lake dynamics on the TP is an important component of global climate change research. With a focus on lakes in the 33° N zone of the central TP, this study investigates the temporal evolution patterns of the lake areas of different types of lakes, i.e., non-glacier-fed endorheic lakes and non-glacier-fed exorheic lakes, during 1988–2017, and examines their relationship with changes in climatic factors. From 1988 to 2017, two endorheic lakes (Lake Yagenco and Lake Zhamcomaqiong) in the study area expanded significantly, i.e., by more than 50%. Over the same period, two exorheic lakes within the study area also exhibited spatio-temporal variability: Lake Gaeencuonama increased by 5.48%, and the change in Lake Zhamuco was not significant. The 2000s was a period of rapid expansion of both the closed lakes (endorheic lakes) and open lakes (exorheic lakes) in the study area. However, the endorheic lakes maintained the increase in lake area after the period of rapid expansion, while the exorheic lakes decreased after significant expansion. During 1988–2017, the annual mean temperature significantly increased at a rate of 0.04 °C/a, while the annual precipitation slightly increased at a rate of 2.23 mm/a. Furthermore, the annual precipitation significantly increased at a rate of 14.28 mm/a during 1995–2008. The results of this study demonstrate that the change in precipitation was responsible for the observed changes in the lake areas of the two exorheic lakes within the study area, while the changes in the lake areas of the two endorheic lakes were more sensitive to the annual mean temperature between 1988 and 2017. Given the importance of lakes to the TP, these are not trivial issues, and we now need accelerated research based on long-term and continuous remote sensing data.
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Chen, W., T. Doko, C. Liu, T. Ichinose, H. Fukui, Q. Feng e P. Gou. "Changes in Rongbuk lake and Imja lake in the Everest region of Himalaya". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-2 (18 de dezembro de 2014): 259–66. http://dx.doi.org/10.5194/isprsarchives-xl-2-259-2014.
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The Himalaya holds the world record in terms of range and elevation. It is one of the most extensively glacierized regions in the world except the Polar Regions. The Himalaya is a region sensitive to climate change. Changes in the glacial regime are indicators of global climate changes. Since the second half of the last century, most Himalayan glaciers have melted due to climate change. These changes directly affected the changes of glacial lakes in the Himalayan region due to the glacier retreat. New glacial lakes are formed, and a number of them have expanded in the Everest region of the Himalayas. This paper focuses on the two glacial lakes which are Imja Lake, located at the southern slope, and Rongbuk Lake, located at the northern slope in the Mt. Everest region, Himalaya to present the spatio-temporal changes from 1976 to 2008. Topographical conditions between two lakes were different (Kruskal-Wallis test, <i>p</i> < 0.05). Rongbuk Lake was located at 623 m higher than Imja Lake, and radiation of Rongbuk Lake was higher than the Imja Lake. Although size of Imja Lake was larger than the Rongbuk Lake in 2008, the growth speed of Rongbuk Lake was accelerating since 2000 and exceeds Imja Lake in 2000–2008. This trend of expansion of Rongbuk Lake is anticipated to be continued in the 21st century. Rongbuk Lake would be the biggest potential risk of glacial lake outburst flood (GLOF) at the Everest region of Himalaya in the future.