Journal articles on the topic 'Overland Lake'
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1
Motiee, Homayoun, and Edward McBean. "An assessment of long-term trends in hydrologic components and implications for water levels in Lake Superior." Hydrology Research 40, no. 6 (November 1, 2009): 564–79. http://dx.doi.org/10.2166/nh.2009.061.
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The combination of climate change and natural periodicities in meteorological variables are demonstrating significant impacts on the water resources of Lake Superior within the Laurentian Great Lakes system of North America. Statistical analyses of long-term records are used to demonstrate how changes over time may be interpreted very differently, depending upon the timeframe over which the analyses are made. Non-linear regression modelling shows that, while increasing trends in overland and overlake precipitation, flows and runoff occurred during the first decades of the twentieth century, very different trends are apparent for the period 1970–2005. For this latter period, increasing rates of air overlake temperature and lake evaporation are occurring but all other parameters are demonstrating decreasing trends. The result is a decline in water levels in Lake Superior at the rate of approximately 1 cm per year over the last 35 years. The results are used to show that to avoid decreasing water levels in Lake Superior, the discharge through St Mary's River must be decreased to approximately one-half the long-term annual average, the results of which will have dramatic implications for ships' cargo levels and hydroelectric energy generation.
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Tuheteru, Edy Jamal, Rudy Sayoga Gautama, Ginting Jalu Kusuma, Arno Adi Kuntoro, Kris Pranoto, and Yosef Palinggi. "Water Balance of Pit Lake Development in the Equatorial Region." Water 13, no. 21 (November 4, 2021): 3106. http://dx.doi.org/10.3390/w13213106.
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In recent years, Indonesia has become the largest coal exporter in the world, and most of the coal is being mined by means of open-pit mining. The closure of an open-pit mine will usually leave a pit morphological landform that, in most cases, will be developed into a pit lake. One of the main issues in developing a pit lake is the understanding of the pit lake filling process. This paper discusses the hydrological model in filling the mineout void in a coal mine in Kalimantan which is located close to the equatorial line. The J-void is a mineout coal pit that is 3000 m long and 1000 m wide, with a maximum depth of 145 m. The development of the J-void pit lake after the last load of coal had been mined out experienced a dynamic process, such as backfilling activities with an overburden as well as pumping mine water from the surrounding pits. There are two components in the model, i.e., overland/subsurface and pit area. The overland zone is simulated using the Rainfall-Runoff NRECA Hydrological Model approach to determine the runoff and groundwater components, whereas the pit area is affected by direct rainfall and evaporation. The model is validated with the observation data. The main source of water in the J-void pit lake is rainwater, both from the surrounding catchment area as well as direct rainfall. As this coal mine area is characterized as a multi-pit area and, consequently, several pit lakes will be formed in the future, the result of the hydrological model is very useful in planning the future pit lakes.
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Salisbury, Michael, Todd DeMunda, and Nicole Walker. "DEVELOPMENT AND VALIDATION OF A STORM SURGE AND WAVE MODEL FOR LAKE HURON (GREAT LAKES, USA)." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 79. http://dx.doi.org/10.9753/icce.v36.waves.79.
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The Federal Emergency Management Agency (FEMA) is tasked with developing flood insurance rate maps along coastlines and major water bodies within the United States, which includes the U.S. portion of the Great Lakes shoreline. Previous flood studies have developed storm surge and wave models of the Great Lakes (including Lake Huron) in support of FEMA’s efforts; however, an independent technical review of those previous coastal flood studies in Lake Huron revealed technical deficiencies in the methods and tools used to generate the wave conditions needed to support overland mapping. Most paramount of these was the fact that starting wave conditions for one dimensional (1D) transformation from a two-dimensional (2D) model were taken from deep water. Using 1D methods to shoal and refract waves to the coastline for runup and/or overland wave analysis may fail to capture the more complex nature of wave refraction/diffraction that 2D wave models can capture. Further, this method omits the development of the directional wave spectra in the nearshore region. To address this concern, a coupled 2D wave and water level model (ADCIRC+SWAN) was developed to hindcast historical storms that have occurred in Lake Huron. These model results will be used to drive the 1D methods to assess nearshore wave hazards from locations near the surfzone limit.
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Kuhn, Catherine, and David Butman. "Declining greenness in Arctic-boreal lakes." Proceedings of the National Academy of Sciences 118, no. 15 (April 5, 2021): e2021219118. http://dx.doi.org/10.1073/pnas.2021219118.
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The highest concentration of the world’s lakes are found in Arctic-boreal regions [C. Verpoorter, T. Kutser, D. A. Seekell, L. J. Tranvik, Geophys. Res. Lett. 41, 6396–6402 (2014)], and consequently are undergoing the most rapid warming [J. E. Overland et al., Arctic Report Card (2018)]. However, the ecological response of Arctic-boreal lakes to warming remains highly uncertain. Historical trends in lake color from remote sensing observations can provide insights into changing lake ecology, yet have not been examined at the pan-Arctic scale. Here, we analyze time series of 30-m Landsat growing season composites to quantify trends in lake greenness for >4 × 105 waterbodies in boreal and Arctic western North America. We find lake greenness declined overall by 15% from the first to the last decade of analysis within the 6.3 × 106-km2 study region but with significant spatial variability. Greening declines were more likely to be found in areas also undergoing increases in air temperature and precipitation. These findings support the hypothesis that warming has increased connectivity between lakes and the land surface [A. Bring et al., J. Geophys. Res. Biogeosciences 121, 621–649 (2016)], with implications for lake carbon cycling and energy budgets. Our study provides spatially explicit information linking climate to pan-Arctic lake color changes, a finding that will help target future ecological monitoring in remote yet rapidly changing regions.
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Otley, Helen M., Sarah A. Munks, and Mark A. Hindell. "Activity patterns, movements and burrows of platypuses (Ornithorhynchus anatinus) in a sub-alpine Tasmanian lake." Australian Journal of Zoology 48, no. 6 (2000): 701. http://dx.doi.org/10.1071/zo99010.
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Adult male and female platypuses were radio-tracked in summer and winter at Lake Lea, north-western Tasmania. They appeared to exhibit greater diurnality, particularly during winter months, a greater degree of overland movement and more frequent use of non-earth refuge sites than do animals inhabiting mainland water bodies. Individuals foraged continuously for up to 16 h, with longer foraging bouts observed during the winter tracking period. Foraging range varied between 2 and 58 ha, with no significant differences observed between the sexes or seasons. All platypuses foraged predominantly in the lake; however, a number of animals were observed moving overland to and from waterbodies and burrows. Burrows were located on lake, creek and pool edges. A high percentage of burrows (25%) were located within dense sedge tussocks and scrub vegetation. Both the terrestrial activity and more opportunistic burrow-site selection may be related to reduced predation pressure in Tasmania.
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DELAFOSSE, PETER H. "West from Salt Lake City: Diaries from the Central Overland Trail." Utah Historical Quarterly 81, no. 1 (January 1, 2013): 92–93. http://dx.doi.org/10.2307/45063394.
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Li, Leilei, Jintao Yang, and Jin Wu. "A Method of Watershed Delineation for Flat Terrain Using Sentinel-2A Imagery and DEM: A Case Study of the Taihu Basin." ISPRS International Journal of Geo-Information 8, no. 12 (November 26, 2019): 528. http://dx.doi.org/10.3390/ijgi8120528.
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Accurate watershed delineation is a precondition for runoff and water quality simulation. Traditional digital elevation model (DEM) may not generate realistic drainage networks due to large depressions and subtle elevation differences in local-scale plains. In this study, we propose a new method for solving the problem of watershed delineation, using the Taihu Basin as a case study. Rivers, lakes, and reservoirs were obtained from Sentinel-2A images with the Canny algorithm on Google Earth Engine (GEE), rather than from DEM, to compose the drainage network. Catchments were delineated by modifying the flow direction of rivers, lakes, reservoirs, and overland flow, instead of using DEM values. A watershed was divided into the following three types: Lake, reservoir, and overland catchment. A total of 2291 river segments, seven lakes, eight reservoirs, and 2306 subwatersheds were retained in this study. Compared with results from HydroSHEDS and Arc Hydro, the proposed method retains crisscross structures in the topology and prevented erroneous streamlines in large lakes. High-resolution Sentinel-2A images available on the GEE have relatively greater merits than DEMs for precisely representing drainage networks and catchments, especially in the plains area. Because of the higher accuracy, this method can be used as a new solution for watershed division in the plains area.
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Maftei, Carmen, Constantin Buta, and Ionela Carazeanu Popovici. "The Impact of Human Interventions and Changes in Climate on the Hydro-Chemical Composition of Techirghiol Lake (Romania)." Water 12, no. 8 (August 12, 2020): 2261. http://dx.doi.org/10.3390/w12082261.
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The aim of this study is to establish the potential effect of changes in climate and anthropic interventions made over time on the hydro-chemical properties of the Techirghiol Lake. Located in the littoral region of the Black Sea, Techirghiol Lake is the most hypersaline lake of Romania—well-known for the therapeutic properties of the saline water and sapropelic mud. Long-term time series of salinity and water level were investigated in relation to the lake water inputs (precipitation, overland flow and groundwater), to chemical parameters (pH, DO and BOD5) and also to the hydraulic works designed and built in the region. The obtained results reveal a degradation of this ecosystem in the period of 1970–1998, when the extensive irrigation practice in the proximity of the lake had a negative effect on the water budget of Techirghiol Lake (an increased freshwater input through runoff and seepage), followed by a major decrease of the lake’s salinity.
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Curry, B. Brandon. "Paleochemistry of Lakes Agassiz and Manitoba based on ostracodes." Canadian Journal of Earth Sciences 34, no. 5 (May 1, 1997): 699–708. http://dx.doi.org/10.1139/e17-056.
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The ionic composition and salinity of Lake Manitoba and its late-glacial precursor, Lake Agassiz, changed significantly over the past 11 000 years. The paleochemical record reported here is based on modern analog environments of ostracodes identified in a new 14.5 m core from southern Lake Manitoba. The ionic composition of Lake Manitoba today is dominated by Na+, Cl−, and HC03−, with much less Ca2+, Mg2+, and K+. Evaporative concentration of modern Lake Manitoba water would lead to greater salinity and the near depletion of Ca2+ due to continued precipitation of calcite. During periods of highest salinity in the Holocene, however, Lake Manitoba supported Limnocythere staplini. Today this species inhabits waters in which [Ca2+] > [HCO3−], including springs associated with groundwater in Paleozoic bedrock discharging into Lake Winnipegosis (and eventually, after much dilution, into Lake Manitoba). Further complicating the Holocene record are intervals containing Limnocythere friabilis that suggest periodic influxes of dilute water, probably from the Assiniboine River, which bypasses Lake Manitoba today. The variations in Holocene paleochemistry indicated by the ostracode record imply changes in the proportion of overland flow plus precipitation relative to groundwater inputs to Lake Manitoba, independent of changes in evaporation relative to precipitation.
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Marston, Richard. "Changes in Geomorphic Processes in the Snake River Following Impoundment of Jackson Lake and Potential Changes Due to 1988 Fires in the Watershed." UW National Parks Service Research Station Annual Reports 15 (January 1, 1991): 152–54. http://dx.doi.org/10.13001/uwnpsrc.1991.3003.
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The purpose of this three-year study is to describe, explain and predict changes in the geomorphology of the Snake River (from Jackson Lake Dam to Moose) and related changes in riparian vegetation due to Jackson Lake Dam and 1988 fires in the watershed. Specific objectives are to determine changes over time and space in: 1) sediment mobilization on hillslopes from rainsplash and overland flow; 2) sediment delivery to streams from slope failures; 3) equilibrium condition and relative stability of the Snake River; and 4) extent of various riparian vegetation communities in the Snake River floodplain.
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Blodgett, Peter J. "“Overland to Los Angeles, by the Salt Lake Route in 1849,” by Judge Walter Van Dyke." Southern California Quarterly 95, no. 4 (2013): 368–79. http://dx.doi.org/10.1525/scq.2013.95.4.368.
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Walter Van Dyke, a young lawyer, headed overland to the California gold rush in 1849 with a large party that started late, traveled through Salt Lake City and over the Old Spanish Trail, and finally arrived in Los Angeles after an eight-month odyssey. He gives his first-hand impressions of the limited opportunities Los Angeles offered in 1850 and credits California’s progress four decades later to American settlers like himself.
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Perry, Robert C., and Donald G. Keefe. "Updated distribution of four stenohaline fish species in Labrador, Canada." Canadian Field-Naturalist 135, no. 2 (October 3, 2021): 153–64. http://dx.doi.org/10.22621/cfn.v135i2.2439.
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Distributions of freshwater fish species in Labrador are poorly documented as the region is remote and sparsely inhabited. Here, we update distributions of four species native to the Labrador Peninsula based on data collected over 10 years: Burbot (Lota lota), Round Whitefish (Prosopium cylindraceum), Lake Trout (Salvelinus namaycush), and Slimy Sculpin (Cottus cognatus). In northern Labrador, our findings extend their ranges inland and northwest of their formerly reported distributions. Their presence in previously unknown locations indicates an alternative post-glacial colonization pathway to one previously proposed that suggested an isolated pocket of Lake Trout in a northern coastal area colonized through marine invasion. Instead, we suggest that overland colonization occurred when glacial Lake Naskaupi withdrew across Quebec into several northern drainages. In southern Labrador, we found Lake Trout and Round Whitefish to the southeast of their previously reported ranges. The discovery of an isolated population of Lake Trout in a remote location of southeast Labrador implies that they may have existed in the area historically (6000 years ago), but have undergone a range contraction with a warming climate. In addition, 22 new locations are documented for Lake Trout within their established range.
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D'Arcy, Pierre, and Richard Carignan. "Influence of catchment topography on water chemistry in southeastern Québec Shield lakes." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 10 (October 1, 1997): 2215–27. http://dx.doi.org/10.1139/f97-129.
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For 30 Canadian Shield lakes of southeastern Quebec, catchment slope and lake morphometry account for 50-70% of the variability of chlorophyll a (Chl a), dissolved organic carbon (DOC), total phosphorus (TP), NO3- , and NH4+ . Dissolved organic carbon, TP, Chl a, Ca, and Mg are negatively related to catchment slope, whereas NO3- and NH4+ increase with increasing slope. Concentrations of more conservative constituents (SO42-, Na, K) increase with decreasing elevation as a result of higher evapotranspiration and lower precipitation at low elevations. Catchment variables (slope, drainage area, percent wetlands) are as good predictors of Chl a (r2 = 0.7) as are water chemistry variables (TP, Ca, Mg, and pH). Dominant vegetation (deciduous vs. coniferous) has little or no influence on lake water chemistry. Hydrogeological data for the Canadian Shield suggest that, during periods of high runoff, the development of waterlogged areas and the importance of overland flow on saturated soils are inversely proportional to catchment slope. We propose that the strong influence of catchment slope on water quality is due to slope-dependent seasonal waterlogging, which determines the fate (retention or export to surface waters) of dissolved substances produced within and moving through the forest floor.
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SZMOLKA, P., and N. FRANK. "ESTIMATION OF THE WATER BUDGET COMPONENTS OF THE SFANTA-ANA CRATER LAKE IN THE EASTERN CARPATHIANS." Meteorologiya i Gidrologiya, no. 9 (September 2022): 65–73. http://dx.doi.org/10.52002/0130-2906-2022-9-65-73.
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Environmental changes of the last decades are taking their toll on Lake Sfanta Ana, a crater lake situated in the Eastern Carpathians. The once crystal-clear water of the lake became greenish and turbid in the past decade due to flourishing algae populations, the surface area, depth and the volume of the water body marked a significant decrease during the past century. These changes are considered to be a consequence of sediment transport from the inner slopes of the crater, eutrophication attributed to nutrients of anthropogenic origin and decrease of water level. Having no permanent surface inflow and outflow sources, the water level of the lake depends on other water-budget components like precipitation, overland inflows during high intensity precipitations or snow-melting, evaporation, subsurface inflow and outflow. The research is aimed to identify the main components of the water budget, based on establishing relations between in situ measured meteorological data and the changes of water level. The results indicate a powerful relationship between water level, precipitation, and evaporation, the latter two are the main factors responsible for the variations of the lake’s water level.
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Stottlemyer, R., and D. Toczydlowski. "Pattern of Solute Movement from Snow into an Upper Michigan Stream." Canadian Journal of Fisheries and Aquatic Sciences 47, no. 2 (February 1, 1990): 290–300. http://dx.doi.org/10.1139/f90-031.
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Precipitation, snowpack, snowmelt, and streamwater samples were collected in a small gauged watershed draining into Lake Superior during winter 1987–88 to assess the importance of snowmelt pattern and meltwater pathways in the occurrence of solute pulses in streamwater. The snowpack along the south shore of Lake Superior can contain 50% of annual precipitation inputs and 38% of annual ionic inputs including moderate levels of strong acids. Throughout winter, thawed surface soils and small but steady snowpack moisture release promoted movement of snowpack solutes to surface mineral soils. Preferential elution of K+, NH4+, and H+ from the snowpack occurred with the initial thaw. Most ions exhibited pulses in snowmelt. Transport of snowpack solutes to the stream during snowmelt was through near-surface soil macropores and overland flow. For those ions with concentrations higher in the snowpack than in the premelt streamwater, K+, NH4+, and H+, the earliest snowmelt pulses had the greatest influence on streamwater chemistry. Unlike other portions of the region with resistant bedrock, the widespread presence of alkaline glacial till provides excess stream acid neutralization capacity (ANC) to buffer acidic inputs. Peak winter streamwater ANC reduction was caused principally by spring melt dilution of base cations and associated alkalinity, constant high SO42− levels, and an increase in NO3−. The maximum reduction in stream ANC was concurrent with overland flow. Relative to its snowmelt concentration, NO3− was highest in streamwater with some stream input likely the result of nitrification and N mineralization.
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XINIAN, WANG, YU FUJIANG, and YIN QINGJIANG. "Research and application of numerical models of typhoon surges in China Seas." MAUSAM 48, no. 4 (November 24, 2021): 595–608. http://dx.doi.org/10.54302/mausam.v48i4.4343.
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In this paper, three numerical models of typhoon surge are discussed briefly. The first one is called Five-basin Model (FbM). The second one is called SLOSH (Sea, Lake and Overland Surges from Hurricanes), 5 SLOSH-type basins covering the entire China coastlines were developed in a joint project between authors and Jelesnianski et al. (1992) of U.S.A. The two models have been used in real-time forecasting of typhoon surge. The third one is a new developing model in which inundation using the scheme originated by Flather and Heaps (1975) and astronomical used was included. A multiple nested grid system was developed.
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Bloxam, Elizabeth, and Per Storemyr. "Old Kingdom Basalt Quarrying Activities at Widan El-Faras, Northern Faiyum Desert." Journal of Egyptian Archaeology 88, no. 1 (December 2002): 23–36. http://dx.doi.org/10.1177/030751330208800103.
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The quarry of Widan el-Faras in the Northern Faiyum Desert was the source of basalt used mainly for paving mortuary temples floors in some of the Fourth and Fifth Dynasty pyramid complexes. An examination of the layout of the quarry and the attached infrastructure, as well as the extracted volumes and the use of the basalt, indicates a campaign-like, seasonal exploitation of the stone linked to the high level of Lake Moeris during the Fourth and Fifth Dynasties. These conditions enabled medium-sized basalt blocks to be transported largely via water to the pyramid construction sites, thus avoiding lengthy and difficult carriage overland.
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Levine, Brian, Lucy Burkitt, Dave Horne, Leo Condron, Chris Tanner, and John Paterson. "Preliminary assessment of the ability of detainment bunds to attenuate sediment and phosphorus transported by surface runoff in the Lake Rotorua catchment." Animal Production Science 60, no. 1 (2020): 154. http://dx.doi.org/10.1071/an18544.
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Water-quality impairment due to excess nutrients entering Lake Rotorua has been recognised since the 1960s. So as to improve water-quality, the 2012 Lake Rotorua Nutrient Management Plan has set a target to reduce phosphorus (P) loads delivered to the lake by 10 t/year from a baseline of ~40 t P/year. Dissolved P and sediment-bound P loss from agriculture have been identified as significant sources of P entering the lake. Storm periods present significant opportunities to mitigate these losses. Detainment bunds (DBs) are a mitigation strategy that could potentially decrease P losses in storm events. A detainment bund is a low earthen dam constructed on productive pasture, which is capable of temporarily ponding large quantities of overland flow delivered by storm-generated ephemeral streams. Prior research on DBs and sedimentation basins serves as a proof of concept for the technology; however, there is no quantitative data available on the capacity of DBs to attenuate contaminants under New Zealand conditions. Quantification of DB performance is essential to the potential implementation of the technology at regional or national scales, and to the modelling of treatment efficacy in nutrient-management software such as OVERSEER®. The present study reports on preliminary data from a DB receiving surface runoff from 19.7 ha within the Lake Rotorua catchment during three contrasting storm events. The results indicated that retaining water in DBs resulted in discharges with decreased volumes of water and decreased concentrations of suspended sediments, dissolved reactive P and total P. Load attenuation related to event size and resulted in decreased loads of sediment (14–91%), dissolved reactive P (19–69%) and total P loads (18–67%) discharged downstream. These preliminary results indicated the potential of this mitigation strategy to decrease loads of sediment and P delivered to Lake Rotorua by surface runoff from pastoral agriculture.
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Demchik, Michael C., Monique L. Sakalidis, Michael Hillstrom, Kyoko Scanlon, Trevor A. Adams, and Katherine R. Minnix. "Evaluating Regeneration in Heterobasidion Root Disease Infested Stands in the Lake States." Forest Science 66, no. 2 (December 4, 2019): 141–44. http://dx.doi.org/10.1093/forsci/fxz074.
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Abstract Heterobasidion root disease (HRD) infection is becoming increasingly common in red pine plantations of the Lake States. Although stump treatment can reduce rates of overland transmission, infested stands continue to experience expansion of mortality pockets. Natural regeneration into HRD mortality pockets can assist with revegetation. The objective of this study was to determine what tree species naturally regenerate in red pine plantations impacted by HRD in Wisconsin and Michigan. We visited 49 pockets (in 31 stands) in Wisconsin and Michigan that had existing confirmed HRD infections during the fall of 2017. We surveyed the regeneration in the pocket and measured the species and basal area of overstory trees 10 m from the expanding edge of the pocket. Overall, pockets were regenerating with desirable species, some of which are susceptible to HRD. Additionally, woody invasive species were present in 39 percent of the pockets. We expect these pockets to generally fill with desirable species of regeneration, although long-term successful regeneration by susceptible species such as pines may be limited.
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Dixon, Kelly J., Shannon A. Novak, Gwen Robbins, Julie M. Schablitsky, G. Richard Scott, and Guy L. Tasa. "“Men, Women, and Children Starving”: Archaeology of the Donner Family Camp." American Antiquity 75, no. 3 (July 2010): 627–56. http://dx.doi.org/10.7183/0002-7316.75.3.627.
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In spring of 1846, the George and Jacob Donner families and some 80 traveling companions began their overland trek to California. When the party ascended the Sierra Nevada in late October, a snowstorm forced the group to bivouac. At this point, the train became separated into two contingents; the larger party camped near Donner Lake and the smaller group—including the Donner families—settled at Alder Creek. Though written accounts from the Lake site imply many resorted to cannibalism, no such records exist for Alder Creek. Here we present archaeological findings that support identification of the Alder Creek camp. We triangulate between historical context, archaeological traces of the camp, and osteological remains to examine the human condition amid the backdrops of starvation and cannibalism. A stepped analytical approach was developed to examine the site’s fragmentary bone assemblage (n= 16,204). Macroscopic and histological analyses indicate that the emigrants consumed domestic cattle and horse and procured wild game, including deer, rabbit, and rodent. Bladed tools were used to extensively process animal tissue. Moreover, bone was being reduced to small fragments; pot polish indicates these fragments were boiled to extract grease. It remains inconclusive, however, whether such processing, or the assemblage, includes human tissue.
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Liu, F., X. Song, L. Yang, Y. Zhang, D. Han, Y. Ma, and H. Bu. "Identifying the origin and geochemical evolution of groundwater using hydrochemistry and stable isotopes in Subei Lake Basin, Ordos energy base, Northwestern China." Hydrology and Earth System Sciences Discussions 11, no. 5 (May 28, 2014): 5709–45. http://dx.doi.org/10.5194/hessd-11-5709-2014.
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Abstract. A hydrochemical and isotopic study was conducted in Subei Lake Basin, northwestern China, to identify the origin and geochemical evolution of groundwater. Water samples were collected, major ions and stable isotopes (δ18O, δ D) were analyzed. In terms of hydrogeological conditions in study area, groundwater can be classified into three types: the Quaternary groundwater, the shallow Cretaceous groundwater, the deep Cretaceous groundwater. Piper diagram and correlation analysis were used to reveal the hydrochemical characteristics of water resources. The dominant water type of lake water was Na-Cl type, which was controlled by strong evaporation and recharge from overland flow and groundwater; the predominant hydrochemical types for groundwater were Ca-HCO3, Na-HCO3, and mixed Ca · Na · Mg-HCO3 types, the groundwater chemistry is mainly controlled by dissolution/precipitation of anhydrite, gypsum, halite and calcite. The dedolomitization and cation exchange are also important factors. Rock weathering is confirmed to play a leading role in the mechanisms responsible for the chemical compositions of groundwater. The stable isotopic values of oxygen and hydrogen in groundwater are close to the local meteoric water line, showing that groundwater is of meteoric origin. The deep Cretaceous groundwater is depleted in heavy isotopes, compared to shallow Cretaceous groundwater. The hydrogen and oxygen isotopes signatures in deep Cretaceous groundwater may show a paleorecharge effect that the deep Cretaceous groundwater was recharged during a geologic period when the climate was wetter and colder than today. Due to strong evaporation effect and dry climatic conditions, heavy isotopes are more enriched in lake water than groundwater. The hydrochemical and isotopic information of utmost importance has been provided to decision-makers by the present study so that a sustainable water resources management policy could be designed for the Ordos energy base.
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Babiarz, Christopher L., James P. Hurley, David P. Krabbenhoft, Cynthia Gilmour, and Brian A. Branfireun. "Application of ultrafiltration and stable isotopic amendments to field studies of mercury partitioning to filterable carbon in lake water and overland runoff." Science of The Total Environment 304, no. 1-3 (March 2003): 295–303. http://dx.doi.org/10.1016/s0048-9697(02)00576-4.
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Jones, Michael T., Lisabeth L. Willey, Derek T. Yorks, Peter D. Hazelton, and Steve L. Johnson. "Passive transport of Eastern Elliptio (Elliptio complanata) by freshwater turtles in New England." Canadian Field-Naturalist 134, no. 1 (July 8, 2020): 56–59. http://dx.doi.org/10.22621/cfn.v134i1.2379.
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Dispersal of freshwater mussels (order Unionida) is primarily as glochidia on the fins and gills of host fish. Adult mussels are more sessile, generally moving short distances (<2 m/week) along lake and river beds. Between 2007 and 2016, we observed seven instances of adult Eastern Elliptio (Elliptio complanata) and one instance of a fingernail clam (Sphaerium sp.) attached to the feet of freshwater turtles in streams and ponds of New England, United States. Observations included five instances of mussels attached to Wood Turtles (Glyptemys insculpta) in Maine and Massachusetts, one instance of a mussel attached to the fingernail of an Eastern Painted Turtle (Chrysemys picta) in Massachusetts, one instance of a mussel attached to a Snapping Turtle (Chelydra serpentina) in Massachusetts, and one instance of a fingernail clam attached to the fingernail of an Eastern Painted Turtle in Massachusetts. We suggest that Eastern Elliptio may be susceptible to transport by freshwater turtles foraging in mussel beds and that transport of adult mussels by freshwater turtles could result in otherwise atypical long-distance, upstream, or overland dispersal between waterbodies.
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Mayo, Talea, and Ning Lin. "The Effect of the Surface Wind Field Representation in the Operational Storm Surge Model of the National Hurricane Center." Atmosphere 10, no. 4 (April 9, 2019): 193. http://dx.doi.org/10.3390/atmos10040193.
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The Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model is the operational storm surge model of the National Hurricane Center (NHC). Previous studies have found that the SLOSH model estimates storm surges with an accuracy of ±20%. In this study, through hindcasts of historical storms, we assess the accuracy of the SLOSH model for four coastal regions in the Northeastern United States. We investigate the potential to improve this accuracy through modification of the wind field representation. We modify the surface background wind field, the parametric wind profile, and the maximum wind speed based on empirical, physical, and observational data. We find that on average the SLOSH model underestimates maximum storm surge heights by 22%. The modifications to the surface background wind field and the parametric wind profile have minor impacts; however, the effect of the modification to maximum wind speed is significant—it increases the variance in the SLOSH model estimates of maximum storm surges, but improves its accuracy overall. We recommend that observed values of maximum wind speed be used in SLOSH model simulations when possible.
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Zhang, Keqi, Yuepeng Li, Huiqing Liu, Jamie Rhome, and Cristina Forbes. "Transition of the Coastal and Estuarine Storm Tide Model to an Operational Storm Surge Forecast Model: A Case Study of the Florida Coast." Weather and Forecasting 28, no. 4 (July 30, 2013): 1019–37. http://dx.doi.org/10.1175/waf-d-12-00076.1.
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Abstract The operational forecast demands and constraints of the National Hurricane Center require that a storm surge model in research mode be tested against a benchmark model such as Sea, Lake, and Overland Surges from Hurricanes (SLOSH) for accuracy, computation time, and numerical stability before the model is used for operational forecasts. Additionally, the simulated results must be in a geographic information system format to facilitate the usage of computed storm surge for various applications. This paper presents results from a demonstration project to explore the pathway for the transition of the Coastal and Estuarine Storm Tide (CEST) model to an operational forecast model by testing CEST over SLOSH basins in Florida. The performance and stability of CEST were examined by conducting simulations for Hurricane Andrew (1992) and more than 100 000 synthetic hurricanes for nine SLOSH basins covering the Florida coast and Lake Okeechobee. The results show that CEST produces peak surge heights similar to those from SLOSH. Additionally, CEST has proven to be numerically stable against all synthetic hurricanes and the computation time of CEST is comparable to that of SLOSH. Therefore, CEST has the potential to be used for operational forecasts of storm surge. The potential of producing more detailed real-time surge inundation forecasts was also investigated through the simulations of Andrew's surge on various grids with different cell sizes. The results indicate that CEST can produce 48-h forecasts using a single processor in about 40 min over a grid generated by reducing the cell edge size of the SLOSH grid by 4 times.
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Dawley, Shawn, Yong Zhang, Xiaoting Liu, Peng Jiang, Geoffrey Tick, HongGuang Sun, Chunmiao Zheng, and Li Chen. "Statistical Analysis of Extreme Events in Precipitation, Stream Discharge, and Groundwater Head Fluctuation: Distribution, Memory, and Correlation." Water 11, no. 4 (April 5, 2019): 707. http://dx.doi.org/10.3390/w11040707.
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Hydrological extremes in the water cycle can significantly affect surface water engineering design, and represents the high-impact response of surface water and groundwater systems to climate change. Statistical analysis of these extreme events provides a convenient way to interpret the nature of, and interaction between, components of the water cycle. This study applies three probability density functions (PDFs), Gumbel, stable, and stretched Gaussian distributions, to capture the distribution of extremes and the full-time series of storm properties (storm duration, intensity, total precipitation, and inter-storm period), stream discharge, lake stage, and groundwater head values observed in the Lake Tuscaloosa watershed, Alabama, USA. To quantify the potentially non-stationary statistics of hydrological extremes, the time-scale local Hurst exponent (TSLHE) was also calculated for the time series data recording both the surface and subsurface hydrological processes. First, results showed that storm duration was most closely related to groundwater recharge compared to the other storm properties, while intensity also had a close relationship with recharge. These relationships were likely due to the effects of oversaturation and overland flow in extreme total precipitation storms. Second, the surface water and groundwater series were persistent according to the TSLHE values, because they were relatively slow evolving systems, while storm properties were anti-persistent since they were rapidly evolving in time. Third, the stretched Gaussian distribution was the most effective PDF to capture the distribution of surface and subsurface hydrological extremes, since this distribution can capture the broad transition from a Gaussian distribution to a power-law one.
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Özgür, Özge. "Byzantine Churches of Enez (Ainis) in Eastern Thrace." Chronos 31 (September 30, 2018): 141–51. http://dx.doi.org/10.31377/chr.v31i0.127.
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The ancient city of Ainos was built on the east coast of the Maritsa (Meriç) river, where the river joins the sea. The city is located on the west of ancient Lake Stentoris (today Gala Lake) and was established on the 7th century BC as a colony of the Aiolians. The excavations at Ainos proved that the city was continuously inhabited since Neolithic era. Ainos was connected in the north to Adrianopolis by sea and by overland route, in the east to Gallipolis and Constantinople and was situated in a very important location. In 148 BC the city was conquered by the Romans and during the Byzantine era it became the capital of the Rhodope region of the Europa province. The location of the city attests its importance as a major commercial center. Today the ancient city of Ainos is situated 3.5 km inside from the coast. Throughout the prehistoric ages, Ainos had two ports and the point that Meriç (Maritsa) River joins today the sea used to be a gulf. Ainos, the most important port city of Eastern Thrace, besides joining the Aegean Sea with the hinterland of Eastern Thrace, was situated at the end of the shortest and most secure road between the Black Sea and the Aegean Sea. During the middle ages the city preserved its importance and as it continued to unite the Aegean islands to Thrace, it was a significant commercial center. Ainos remained a major commercial center until the beginning of the 19th century
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Bitton, Davis, and Lannon W. Mintz. "The Trail: A Bibliography of the Travelers on the Overland Trail to California, Oregon, Salt Lake City, and Montana during the Years 1841-1864." Western Historical Quarterly 19, no. 3 (August 1988): 339. http://dx.doi.org/10.2307/968256.
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Donald, David B., and David J. Alger. "Geographic distribution, species displacement, and niche overlap for lake trout and bull trout in mountain lakes." Canadian Journal of Zoology 71, no. 2 (February 1, 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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Cordeiro, Marcos R. C., Kang Liang, Henry F. Wilson, Jason Vanrobaeys, David A. Lobb, Xing Fang, and John W. Pomeroy. "Simulating the hydrological impacts of land use conversion from annual crop to perennial forage in the Canadian Prairies using the Cold Regions Hydrological Modelling platform." Hydrology and Earth System Sciences 26, no. 22 (November 25, 2022): 5917–31. http://dx.doi.org/10.5194/hess-26-5917-2022.
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Abstract. The Red River is one of the largest contributing sources of discharge and nutrients to the world's 10th largest freshwater lake, Lake Winnipeg. Conversion of large areas of annual cropland to perennial forage has been proposed as a strategy to reduce both flooding and nutrient export to Lake Winnipeg. Such reductions could occur either via a reduction in the concentration of nutrients in runoff or through changes in the basin-scale hydrology, resulting in a lower water yield and the concomitant export of nutrients. This study assessed the latter mechanism by using the physically based Cold Regions Hydrological Modelling platform to examine the hydrological impacts of land use conversion from annual crops to perennial forage in a subbasin of the La Salle River basin in Canada. This basin is a typical agricultural subbasin in the Red River Valley, characterised by flat topography, clay soils, and a cold subhumid, continental climate. Long-term simulations (1992–2013) of the major components of water balance were compared between canola and smooth bromegrass, representing a conversion from annual cropping systems to perennial forage. An uncertainty framework was used to represent a range of fall soil saturation status (0 % to 70 %), which governs the infiltration to frozen soil in the subsequent spring. The model simulations indicated that, on average, there was a 36.5 ± 6.6 % (36.5 ± 7.2 mm) reduction in annual cumulative discharge and a 29.9 ± 16.3 % (2.6 ± 1.6 m3 s−1) reduction in annual peak discharge due to forage conversion over the assessed period. These reductions were driven by reduced overland flow 52.9 ± 12.8 % (28.8 ± 10.1 mm), increased peak snowpack (8.1 ± 1.5 %, 7.8 ± 1.6 mm), and enhanced infiltration to frozen soils (66.7 ± 7.7 %, 141.5 ± 15.2 mm). Higher cumulative evapotranspiration (ET) from perennial forage (34.5 ± 0.9 %, 94.1 ± 2.5 mm) was also predicted by the simulations. Overall, daily soil moisture under perennial forage was 18.0 % (57.2 ± 1.2 mm) higher than that of crop simulation, likely due to the higher snow water equivalent (SWE) and enhanced infiltration. However, the impact of forage conversion on daily soil moisture varied interannually. Soil moisture under perennial forage stands could be either higher or lower than that of annual crops, depending on antecedent spring snowmelt infiltration volumes.
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Macpherson, Andrew, John A. Holmes, Andrew M. Muir, and David L. G. Noakes. "Assessing feeding competition between lake whitefish Coregonus clupeaformis and round whitefish Prosopium cylindraceum." Current Zoology 56, no. 1 (February 1, 2010): 109–17. http://dx.doi.org/10.1093/czoolo/56.1.109.
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Abstract We collected lake whitefish Coregonus clupeaformis and round whitefish Prosopium cylindraceum from the main basin of Lake Huron and Georgian Bay in the Laurentian Great Lakes of North America to investigate details of diet and feeding tactics of these species in different seasons. Lake whitefish supports important commercial fisheries in Lake Huron and both species make use of habitats near the Bruce Nuclear Power Development, on the eastern shore of Lake Huron. Most fish of both species showed generalist feeding behavior, but some lake whitefish appeared to show specialist prey selection. The invasive spiny water flea Bythotrephes longimanus was an important component of the diet of both species. There was considerable dietary overlap between the whitefish species, but the ecological implications of these dietary overlaps are mitigated by the fact that dominant prey species differed in most seasons. We conclude that the potential for ecologically significant interactions between lake whitefish and round whitefish resulting from competition for similar benthic food resources in the main basin of Lake Huron is probably low.
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Layhee, Megan, Miho Yoshioka, Bahram Farokhkish, Jackson A. Gross, and Adam J. Sepulveda. "Toxicity of a Traditional Molluscicide to Asian Clam Veligers." Journal of Fish and Wildlife Management 5, no. 1 (December 1, 2013): 141–45. http://dx.doi.org/10.3996/042013-jfwm-032.
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Abstract Aquaculture and hatchery industries are in need of effective control methods to reduce the risk of spreading aquatic invasive species, such as the Asian clam Corbicula fluminea, through aquaculture and hatchery activities. The planktonic nature of Asian clam veligers enables this life stage to enter water-based infrastructure undetected, including hatchery trucks used to stock fish. Once in hatchery trucks, veligers can disperse overland and establish in previously uninvaded habitats. As a result, there is a need to develop techniques that result in veliger mortality but do not harm fish. In September 2012, we conducted laboratory trials to determine if a molluscicide (750 mg/L potassium chloride and 25 mg/L formalin) commonly used to kill zebra mussel (Dreissena polymorpha) veligers in hatchery trucks can also effectively kill Asian clam veligers. We exposed Asian clam veligers to this molluscicide for 1, 3, and 5 h in each of two water types: deionized water and filtered lake water. We found <20% mortality at the 1-h exposure period and 100% mortality at both the 3-h and 5-h exposure periods, regardless of water type. This laboratory study represents an important step toward reducing the spread of Asian clams by aquaculture facilities.
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Bufalini, Margherita, Marco Materazzi, Chiara Martinello, Edoardo Rotigliano, Gilberto Pambianchi, Michele Tromboni, and Marco Paniccià. "Soil Erosion and Deposition Rate Inside an Artificial Reservoir in Central Italy: Bathymetry versus RUSLE and Morphometry." Land 11, no. 11 (October 28, 2022): 1924. http://dx.doi.org/10.3390/land11111924.
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This study, using different direct and indirect methodologies, evaluated the sedimentation rate in an artificial reservoir in central Italy. This reservoir is regionally representative and was built in the 1960s for hydroelectric purposes; it has experienced a strong decrease in trap efficiency and a loss of over 70% of the stored water volume. Direct measurements of the lake bottom bathymetry, carried out in 2006 and 2015, and 3D reconstructions performed in a GIS environment, made it possible to calculate the volume of filling material and to verify an increasing trend in the sedimentation rate since 2006. The sample reservoir denudation rate was compared with that obtained using the Revised Universal Soil Loss Equation method to calibrate the fundamental and critical factors of the method itself, and verify the contribution of a hydrological “direct” (through new channels or gullies) or “diffuse” (overland flow) connectivity. Furthermore, the comparison with the results obtained from past studies on ten other artificial regional reservoirs, performed with morphometric analysis, demonstrated a good relationship between soil erosion rate, stream frequency, and contributing area size. The study highlighted how a correct estimate of soil erosion and/or solid transport rates within a hydrographic basin is fundamental for the assessment of the trap efficiency of a reservoir, in a period in which the availability of water resources is becoming more and more vital.
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Rouse, Wayne R., Peter D. Blanken, Normand Bussières, Anne E. Walker, Claire J. Oswald, William M. Schertzer, and Christopher Spence. "An Investigation of the Thermal and Energy Balance Regimes of Great Slave and Great Bear Lakes." Journal of Hydrometeorology 9, no. 6 (December 1, 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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Kraemer, Benjamin M., Rachel M. Pilla, R. Iestyn Woolway, Orlane Anneville, Syuhei Ban, William Colom-Montero, Shawn P. Devlin, et al. "Climate change drives widespread shifts in lake thermal habitat." Nature Climate Change 11, no. 6 (June 2021): 521–29. http://dx.doi.org/10.1038/s41558-021-01060-3.
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AbstractLake surfaces are warming worldwide, raising concerns about lake organism responses to thermal habitat changes. Species may cope with temperature increases by shifting their seasonality or their depth to track suitable thermal habitats, but these responses may be constrained by ecological interactions, life histories or limiting resources. Here we use 32 million temperature measurements from 139 lakes to quantify thermal habitat change (percentage of non-overlap) and assess how this change is exacerbated by potential habitat constraints. Long-term temperature change resulted in an average 6.2% non-overlap between thermal habitats in baseline (1978–1995) and recent (1996–2013) time periods, with non-overlap increasing to 19.4% on average when habitats were restricted by season and depth. Tropical lakes exhibited substantially higher thermal non-overlap compared with lakes at other latitudes. Lakes with high thermal habitat change coincided with those having numerous endemic species, suggesting that conservation actions should consider thermal habitat change to preserve lake biodiversity.
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Foley, Carolyn J., Gabriel J. Bowen, Thomas F. Nalepa, Marisol S. Sepúlveda, and Tomas O. Höök. "Stable isotope patterns of benthic organisms from the Great Lakes region indicate variable dietary overlap of Diporeia spp. and dreissenid mussels." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 12 (December 2014): 1784–95. http://dx.doi.org/10.1139/cjfas-2013-0620.
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Competition between native and invasive species may bring about a suite of ecological and evolutionary outcomes, including local extirpations. In the Laurentian Great Lakes, competition for food may explain the dramatic decline of Diporeia spp. amphipods following the introduction of dreissenid mussels. This hypothesis has not been confirmed, in part because dreissenids and Diporeia appear to co-exist and flourish in other systems, including the Finger Lakes of New York. We used carbon, nitrogen, hydrogen, and oxygen stable isotope ratios to examine resource use by Diporeia from three spatially distinct populations (Lake Michigan, Lake Superior, and Cayuga Lake), dreissenids from areas where they co-occur with Diporeia (Lake Michigan and Cayuga Lake), and Diporeia from Lake Michigan collected before and after dreissenid invasion (1986–2009). Our results suggest that dreissenids may affect resource use by Diporeia in areas of co-occurrence, but the extent to which those effects are positive or negative is unclear. Terrestrial inputs may provide an important subsidy for Diporeia populations in small systems but may not be substantial enough in the Great Lakes to ensure that both taxa thrive.
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Park, Chan Hee, and Peter M. Huck. "A Conceptual Model for Cryptosporidium Transport in Watersheds." Water Quality Research Journal 38, no. 1 (February 1, 2003): 77–113. http://dx.doi.org/10.2166/wqrj.2003.006.
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Abstract This paper describes a conceptual model to estimate Cryptosporidium parvum oocyst transport from source to water treatment plant intake. The intent of the model is ultimately to be able to predict oocyst concentrations at an intake to an order-of-magnitude level. The transport and fate mechanisms included are: oocyst detachment from waste or soil, generation of runoff, overland transport, reservoir and in-stream transport, and oocyst die-off. The model is formulated in finite difference form, and deals with both non-point sources from manure-applied areas, and point sources from wastewater treatment plants. An important contribution of this work is the recognition that the settling rates of free and floc- or particle-associated oocysts can be considerably different. This has important implications for their transport. A finite difference scheme was developed for five sections of a hypothetical watershed: a point source, a lake or reservoir (which can be modelled as either a continuous stirred tank reactor or an ideal rectangular setting tank), the section of stream channel from the outlet of the lake or reservoir to the confluence with another stream, a tributary with a non-point source, and the stream section from the confluence to a water treatment plant intake. The stream confluence is handled with a simple mass and flow balance. It would be very expensive to collect the necessary data to test the model. Because an appropriate data set was not available, the model was tested by means of a sensitivity analysis for the hypothetical watershed, using reasonable parameter settings for the base case. The major contribution of the model is in defining the mechanisms involved in oocyst transport within a watershed. It gives important insights into the significance of various factors, provides a basis for data collection, and identifies areas where experimental investigations are required to avoid the need for simplifying assumptions. At its current state of development, the model cannot be used to provide quantitative predictions, but defines a base from which further detailed modelling can be developed to aid in decisionmaking for pathogen control. Using the framework that this model provides, contributions from other sources of Cryptosporidium oocysts such as domestic animals and combined sewage overflows could also be modelled.
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Bailey, R. E., and L. Margolis. "Comparison of parasite fauna of juvenile sockeye salmon (Oncorhynchus nerka) from southern British Columbian and Washington State lakes." Canadian Journal of Zoology 65, no. 2 (February 1, 1987): 420–31. http://dx.doi.org/10.1139/z87-063.
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Sixteen species and juveniles of four taxa of parasites (Myxosporea, 4; Monogenea, 1; Trematoda, 5; Cestoda, 4; Nematoda, 2; Acanthocephala, 2; Copepoda, 2) were encountered in 1550 sockeye salmon (Oncorhynchus nerka) smolts and presmolts examined from 15 Fraser River lakes, Nimpkish Lake on Vancouver Island, and Lake Washington, Washington State, U.S.A. The most common taxa were Diphyllobothrium sp. (spp.?) plerocercoids, Philonema agubernaculum, Eubothrium sp., and Proteocephalus sp. Various statistical techniques (K - nearest neighbour and cluster analyses based on Jaccard and percent dissimilarity matrices) were used to compare the parasite fauna in sockeye from the different lakes. K - nearest neighbour analysis demonstrated that considerable overlap existed among many of the studied lakes, whereas little overlap occurred among other lakes. Cluster analyses revealed similar faunas among some lakes within biogeoclimatic zones and lakes of similar trophic status. Cluster analyses also revealed parasites that tended to co-occur. Parasites with similar modes of transmission or geographic range tended to cluster together.
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Baklagin, Nikolaevich Vyacheslav. "Selection of Parameters and Architecture of Multilayer Perceptrons for Predicting Ice Coverage of Lakes." Ekológia (Bratislava) 36, no. 3 (September 1, 2017): 226–34. http://dx.doi.org/10.1515/eko-2017-0019.
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Abstract The ice cover on lakes is one of the most influential factors in the lakes’ winter aquatic ecosystem. The paper presents a method for predicting ice coverage of lakes by means of multilayer perceptrons. This approach is based on historical data on the ice coverage of lakes taking Lake Onega as an example. The daily time series of ice coverage of Lake Onega for 2004–2017 was collected by means of satellite data analysis of snow and ice cover of the Northern Hemisphere. Input signals parameters for the multilayer perceptrons aimed at predicting ice coverage of lakes are based on the correlation analysis of this time series. The results of training of multilayer perceptrons showed that perceptrons with architectures of 3-2-1 within the Freeze-up phase (arithmetic mean of the mean square errors for training epoch $\overline {MSE} = 0.0155$ ) and 3-6-1 within the Break-up phase ( $\overline {MSE} = 0.0105$ ) have the least mean-squared error for the last training epoch. Tests within the holdout samples prove that multilayer perceptrons give more adequate and reliable prediction of the ice coverage of Lake Onega (mean-squared prediction error MSPE = 0.0076) comparing with statistical methods such as linear regression, moving average and autoregressive analyses of the first and second order.
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Mehl, Katherine R., and Ray T. Alisauskas. "King Eider (Somateria Spectabilis) Brood Ecology: Correlates of Duckling Survival." Auk 124, no. 2 (April 1, 2007): 606–18. http://dx.doi.org/10.1093/auk/124.2.606.
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AbstractEvents during duckling growth can influence waterfowl population dynamics. To gain insight into King Eider (Somateria spectabilis) brood ecology, we monitored 111 and 46 individually marked ducklings from broods of 23 and 11 radiomarked King Eiders during 2000 and 2001, respectively. We used capture-mark-resight data to model apparent survival of King Eider ducklings and broods, and multistratum analysis to estimate probabilities of (1) movement among habitats and (2) apparent survival of ducklings that used various habitats. In addition, we recorded length of stay for 7 and 18 radiomarked females with failed nesting attempts during 2000 and 2001, respectively. Complete loss of individual broods accounted for 84% of all duckling mortality (106 of 126 mortalities), with most brood loss (74%; 17 of 23 broods lost) within the first two days after hatch. Estimated apparent survival of ducklings to 24 days of age was 0.10 (95% CI: 0.05 to 0.15). Apparent survival of broods was estimated to be 0.31 (95% CI: 0.13 to 0.50). Our data suggested an interaction between female size and hatch date, whereby larger females whose ducklings also hatched earlier raised more ducklings than either small females or those with ducklings that hatched later. Overland brood movements ≥1 km occurred in both years, and survival was greatest for ducklings on smaller ponds away from the central nesting area at Karrak Lake, Nunavut. Females that experienced nest failure and total brood loss left the study area earlier than females with surviving ducklings.Écologie d'élevage des couvées de Somateria spectabilis : Corrélations avec la survie des canetons
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Zachry, Brian C., William J. Booth, Jamie R. Rhome, and Tarah M. Sharon. "A National View of Storm Surge Risk and Inundation." Weather, Climate, and Society 7, no. 2 (April 1, 2015): 109–17. http://dx.doi.org/10.1175/wcas-d-14-00049.1.
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Abstract The National Oceanic and Atmospheric Administration (NOAA), specifically the National Weather Service’s (NWS) National Hurricane Center (NHC), utilizes the hydrodynamic Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model to simulate storm surge in 27 basins along the U.S East and Gulf Coasts. This information is provided to federal, state, and local partners to assist in a range of planning processes, risk assessment studies, and decision making. Based on climatology, tens of thousands of hypothetical hurricanes are simulated in each basin, and the potential storm surges are calculated. Storm surge composites—maximum envelopes of water (MEOWs) and maximum of maximums (MOMs)—are created to assess and visualize storm surge risk under varying conditions. While MEOWs and MOMs provide a local assessment of storm surge risk, they do not provide a national perspective owing to the 27 discrete grids. National assessments must therefore merge the grids together, which is a laborious task requiring considerable SLOSH and hydrodynamic modeling expertise. This paper describes the technique used to create national inundation maps for category 1–5 hurricanes using the SLOSH MOM product, and it provides a simple quantitative assessment of the potential societal impacts. Approximately 22 million people along the U.S East and Gulf Coasts are vulnerable to storm surge. For all hurricane categories, a substantial portion of the coastal population and housing units are at risk, and many evacuation routes become inundated. Florida is the most vulnerable state with 40% of its population at risk. These maps and analyses provide a new way to view, analyze, and communicate national storm surge risk and inundation.
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Kao, Yu-Chun, Renee E. Renauer-Bova, David B. Bunnell, Owen T. Gorman, and Randy L. Eshenroder. "Distributions of Cisco (Coregonus artedi) in the upper Great Lakes in the mid-twentieth century, when populations were in decline." PLOS ONE 17, no. 12 (December 22, 2022): e0276109. http://dx.doi.org/10.1371/journal.pone.0276109.
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The restoration of the once abundant Cisco (Coregonus artedi) is a management interest across the Laurentian Great Lakes. To inform the restoration, we (1) described historical distributions of Cisco and (2) explored whether non-indigenous Rainbow Smelt (Osmerus mordax) and Alewife (Alosa pseudoharengus) played a role in the decline of Cisco populations across the upper Great Lakes (i.e., Lakes Superior, Michigan, and Huron). Our source data were collected from fishery-independent surveys conducted by the U.S. Fish and Wildlife Service’s research vessel R/V Cisco in 1952–1962. By analyzing data collected by gill-net surveys, we confirmed the importance of embayment and shallow-water habitats to Cisco. We found that Cisco was abundant in Whitefish Bay and Keweenaw Bay, Lake Superior, and in Green Bay, Lake Michigan, but we also found a sign of Cisco extirpation in Saginaw Bay, Lake Huron. Our results also showed that Ciscoes generally stayed in waters <80 m in bottom depth throughout the year. However, a substantial number of Ciscoes stayed in very deep waters (>150 m in bottom depth) in summer and fall in Lake Michigan, although we cannot exclude the possibility that these Ciscoes had hybridized with the other Coregonus species. By comparing complementary data collected from bottom-trawl surveys, we concluded that the spatiotemporal overlap between Rainbow Smelt and Cisco likely occurred across the upper Great Lakes throughout 1952–1962. These data were consistent with the hypothesis that Rainbow Smelt played a role in the decline of Cisco populations across the upper Great Lakes in the period. We also found that the spatiotemporal overlap between Alewife and Cisco likely occurred only in Saginaw Bay in fall 1956 and in Lake Michigan after 1960. Thus, any potential recovery of Cisco after the 1950s could have been inhibited by Alewife in Lakes Michigan and Huron.
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Davis, Bruce M., and Thomas N. Todd. "Competition between larval lake herring (Coregonus artedi) and lake whitefish (Coregonus clupeaformis) for zooplankton." Canadian Journal of Fisheries and Aquatic Sciences 55, no. 5 (May 1, 1998): 1140–48. http://dx.doi.org/10.1139/f98-004.
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Diet and growth of larval lake herring (Coregonus artedi) and lake whitefish (Coregonus clupeaformis) were compared in mesocosm experiments in a small mesotrophic lake in southeastern Michigan. Fish were sampled from single-species and mixed assemblages in 2-m3 cages for 8 weeks during April and May. Both species initially ate mostly cyclopoid copepodites and small cladocerans (Bosmina spp.). Schoener's index of diet overlap showed considerable overlap (70-90%). Lake whitefish ate Daphnia spp. and adult copepods about 2 weeks earlier than did lake herring, perhaps related to their larger mean mouth gape. Lake whitefish were consistently larger than lake herring until the eighth week, especially in the sympatric treatments. Lake whitefish appeared to have a negative effect on the growth of lake herring, as lake herring in mixed-species treatments were smaller and weighed less than lake herring reared in single-species treatments. The diet similarities of lake whitefish and lake herring larvae could make them competitors for food in the Great Lakes. The greater initial size of lake whitefish could allow them to eat larger prey earlier and thereby limit availability of these prey to lake herring at a crucial period of development.
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Laird, Neil, Alicia M. Bentley, Sara A. Ganetis, Andrew Stieneke, and Samantha A. Tushaus. "Climatology of Lake-Effect Precipitation Events over Lake Tahoe and Pyramid Lake." Journal of Applied Meteorology and Climatology 55, no. 2 (February 2016): 297–312. http://dx.doi.org/10.1175/jamc-d-14-0230.1.
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AbstractThe frequency, timing, and environmental conditions of lake-effect (LE) precipitation over Lake Tahoe and Pyramid Lake in northern California and western Nevada were examined for the 14 winters (September–March) from 1996/97 through 2009/10. Weather Surveillance Radar-1988 Doppler (WSR-88D) data from Reno, Nevada (KRGX), were used to identify 62 LE events. LE precipitation occurred as single bands extending downwind from overlake areas, and as isolated regions of overlake precipitation with little or no extension over land. Mesoscale vortices were also identified during both Lake Tahoe and Pyramid Lake LE events. An average of 4.4 LE events occurred each winter in the Lake Tahoe and Pyramid Lake region, with events occurring most frequently in October. LE events had an average duration of 6.3 h, approximately half the duration of LE events observed over Lake Champlain, the New York State Finger Lakes, or the Great Salt Lake. The observed conditions during LE events in the Lake Tahoe and Pyramid Lake region typically had 1) mean surface air temperatures below freezing, 2) mean surface wind speeds of <2.0 m s−1 (notably weaker than during lake effect in other areas), 3) a mean lake–air temperature difference of 11.5°C, and 4) a mean lake–700-hPa temperature difference of 20.9°C.
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Savage, Thomas J. "Emeline and Jeremiah." California History 93, no. 2 (2016): 31–56. http://dx.doi.org/10.1525/ch.2016.93.2.31.
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On November 2, 1850, Jeremiah Root published a “Notice” in the Sacramento Transcript offering a reward for the arrest of his wife, Emeline, who had absconded with a younger man, twelve thousand dollars, and their two-year-old daughter, leaving Root and their five sons to fend for themselves at the roadhouse they ran along the American River. When Emeline and their daughter were found three months later on a bark in San Francisco preparing to leave California, Jeremiah met with her and the couple quickly reconciled. Charges were dropped against Emeline and her associates, and Jeremiah and the rest of their family joined her on the ship to travel east. The Transcript editorialized against the apparent tawdry nature of the affair, but a deeper inspection of the history of this forty-niner family reveals in intimate detail how Jeremiah and Emeline's personal struggles emerged from the incredible physical and spiritual turmoil experienced by early Mormon emigrants, who played a seminal role in Gold Rush–era California. Emeline and Jeremiah Root were early converts to Mormonism and arrived in California having survived a twelve-year odyssey that began in Kirtland, Ohio. They were expelled first from Kirtland and then from Nauvoo, Illinois, after the murder of their church leader, Joseph Smith. They persevered through starvation and malnutrition at Winter Quarters on the Missouri River while following Brigham Young to Salt Lake. They struggled with spiritual allegiances as the practice of polygamy and economic inequities became apparent among church leadership, and they ultimately defied Brigham Young by taking the physically demanding overland route from Salt Lake through the Forty-Mile Desert and over the Carson Pass to Gold Rush California in early 1849. Finally, they lived through a tumultuous year on the lower American River, surviving among unruly miners, deadly shootouts over property rights, and a rampant outbreak of cholera. These pressures erupted into a personal crisis when Emeline escaped, escorted by a family friend who was perhaps her lover, taking her only daughter and the family fortune with her. Emeline and Jeremiah's eventual reconciliation and the way Jeremiah ultimately lived out his life revealed them to be people of personal and spiritual integrity who, in this one incident, were overwhelmed by the struggles of the times. Their story illustrates the incredible resiliency of early California pioneers and integrates in vivid detail the physical, spiritual, and emotional challenges facing families in Gold Rush–era California.
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Yang, Kang, Laurence C. Smith, Leif Karlstrom, Matthew G. Cooper, Marco Tedesco, Dirk van As, Xiao Cheng, Zhuoqi Chen, and Manchun Li. "A new surface meltwater routing model for use on the Greenland Ice Sheet surface." Cryosphere 12, no. 12 (November 30, 2018): 3791–811. http://dx.doi.org/10.5194/tc-12-3791-2018.
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Abstract. Large volumes of surface meltwater are routed through supraglacial internally drained catchments (IDCs) on the Greenland Ice Sheet surface each summer. Because surface routing impacts the timing and discharge of meltwater entering the ice sheet through moulins, accurately modeling moulin hydrographs is crucial for correctly coupling surface energy and mass balance models with subglacial hydrology and ice dynamics. Yet surface routing of meltwater on ice sheets remains a poorly understood physical process. We use high-resolution (0.5 m) satellite imagery and a derivative high-resolution (3.0 m) digital elevation model to partition the runoff-contributing area of the Rio Behar catchment, a moderately sized (∼63 km2) mid-elevation (1207–1381 m) IDC in the southwestern Greenland ablation zone, into open meltwater channels (supraglacial streams and rivers) and interfluves (small upland areas draining to surface channels, also called “hillslopes” in terrestrial geomorphology). A simultaneous in situ moulin discharge hydrograph was previously acquired for this catchment in July 2015. By combining the in situ discharge measurements with remote sensing and classic hydrological theory, we determine mean meltwater routing velocities through open channels and interfluves within the catchment. Two traditional terrestrial hydrology surface routing models, the unit hydrograph and rescaled width function, are applied and also compared with a surface routing and lake-filling model. We conclude that (1) surface meltwater is routed by slow interfluve flow (∼10-3–10−4 m s−1) and fast open-channel flow (∼10-1 m s−1); (2) the slow interfluve velocities are physically consistent with shallow, unsaturated subsurface porous media flow (∼10-4–10−5 m s−1) more than overland sheet flow (∼10-2 m s−1); (3) the open-channel velocities yield mean Manning's roughness coefficient (n) values of ∼0.03–0.05 averaged across the Rio Behar supraglacial stream–river network; (4) interfluve and open-channel flow travel distances have mean length scales of ∼100–101 m and ∼103 m, respectively; and (5) seasonal evolution of supraglacial drainage density will alter these length scales and the proportion of interfluves vs. open channels and thus the magnitude and timing of meltwater discharge received at the outlet moulin. This phenomenon may explain seasonal subglacial water pressure variations measured in a borehole ∼20 km away. In general, we conclude that in addition to fast open-channel transport through supraglacial streams and rivers, slow interfluve processes must also be considered in ice sheet surface meltwater routing models. Interfluves are characterized by slow overland and/or shallow subsurface flow, and it appears that shallow unsaturated porous-media flow occurs even in the bare-ice ablation zone. Together, both interfluves and open channels combine to modulate the timing and discharge of meltwater reaching IDC outlet moulins, prior to further modification by englacial and subglacial processes.
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Fiskal, Annika, Longhui Deng, Anja Michel, Philip Eickenbusch, Xingguo Han, Lorenzo Lagostina, Rong Zhu, et al. "Effects of eutrophication on sedimentary organic carbon cycling in five temperate lakes." Biogeosciences 16, no. 19 (September 30, 2019): 3725–46. http://dx.doi.org/10.5194/bg-16-3725-2019.
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Abstract. Even though human-induced eutrophication has severely impacted temperate lake ecosystems over the last centuries, the effects on total organic carbon (TOC) burial and mineralization are not well understood. We study these effects based on sedimentary records from the last 180 years in five Swiss lakes that differ in trophic state. We compare changes in TOC content and modeled TOC accumulation rates through time to historical data on algae blooms, water column anoxia, wastewater treatment, artificial lake ventilation, and water column phosphorus (P) concentrations. We furthermore investigate the effects of eutrophication on rates of microbial TOC mineralization and vertical distributions of microbial respiration reactions in sediments. Our results indicate that the history of eutrophication is well recorded in the sedimentary record. Overall, eutrophic lakes have higher TOC burial and accumulation rates, and subsurface peaks in TOC coincide with past periods of elevated P concentrations in lake water. Sediments of eutrophic lakes, moreover, have higher rates of total respiration and higher contributions of methanogenesis to total respiration. However, we found strong overlaps in the distributions of respiration reactions involving different electron acceptors in all lakes regardless of lake trophic state. Moreover, even though water column P concentrations have been reduced by ∼ 50 %–90 % since the period of peak eutrophication in the 1970s, TOC burial and accumulation rates have only decreased significantly, by ∼ 20 % and 25 %, in two of the five lakes. Hereby there is no clear relationship between the magnitude of the P concentration decrease and the change in TOC burial and accumulation rate. Instead, data from one eutrophic lake suggest that artificial ventilation, which has been used to prevent water column anoxia in this lake for 35 years, may help sustain high rates of TOC burial and accumulation in sediments despite water column P concentrations being strongly reduced. Our study provides novel insights into the influence of human activities in lakes and lake watersheds on lake sediments as carbon sinks and habitats for diverse microbial respiration processes.
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Melling, David R., Charles E. Blackburn, David H. Watkinson, and Jack R. Parker. "Geological setting of gold, western Wabigoon Subprovince, Canadian Shield: exploration targets in mixed volcanic successions." Canadian Journal of Earth Sciences 25, no. 12 (December 1, 1988): 2075–88. http://dx.doi.org/10.1139/e88-192.
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The Archean volcanic rocks in the Cameron–Rowan lakes area may be divided into three distinct successions based on field mapping, petrographic studies, and lithogeochemical characteristics. The lowermost Rowan Lake Volcanics are tholeiitic pillowed basalts. These rocks are unconformably overlain by the Cameron Lake Volcanics, a mixed succession of tholeiitic massive and pillowed basalts and intermediate to felsic volcaniclastic rocks. The Brooks Lake Volcanics consist of tholeiitic basalts and represent the youngest volcanic rocks at the top of the preserved succession.Most of the gold concentrations in the Cameron–Rowan lakes area are confined to the mixed Cameron Lake Volcanics. The majority of these, including the Cameron Lake deposit, occur within shear zones near lithologic contacts. In the Eagle–Wabigoon and Manitou lakes areas there are similar stratigraphic subdivisions of the supracrustal rocks and many of the gold concentrations also occur in deformation zones within the mixed volcanic successions. The contrasting competencies among the basalts, the intermediate to felsic volcaniclastic rocks, and the intrusive rocks, which are characteristic of the mixed volcanic successions, localized stress during deformation, forming shear zones into which gold-bearing fluids gained access. The potential for successfully delineating economic gold concentrations appears greatest in the mixed volcanic successions within these areas and elsewhere in the western Wabigoon Subprovince of the Canadian Shield.
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Notaro, Michael, Val Bennington, and Brent Lofgren. "Dynamical Downscaling–Based Projections of Great Lakes Water Levels*+." Journal of Climate 28, no. 24 (December 15, 2015): 9721–45. http://dx.doi.org/10.1175/jcli-d-14-00847.1.
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Abstract Projections of regional climate, net basin supply (NBS), and water levels are developed for the mid- and late twenty-first century across the Laurentian Great Lakes basin. Two state-of-the-art global climate models (GCMs) are dynamically downscaled using a regional climate model (RCM) interactively coupled to a one-dimensional lake model, and then a hydrologic routing model is forced with time series of perturbed NBS. The dynamical downscaling and coupling with a lake model to represent the Great Lakes create added value beyond the parent GCM in terms of simulated seasonal cycles of temperature, precipitation, and surface fluxes. However, limitations related to this rudimentary treatment of the Great Lakes result in warm summer biases in lake temperatures, excessive ice cover, and an abnormally early peak in lake evaporation. While the downscaling of both GCMs led to consistent projections of increases in annual air temperature, precipitation, and all NBS components (overlake precipitation, basinwide runoff, and lake evaporation), the resulting projected water level trends are opposite in sign. Clearly, it is not sufficient to correctly simulate the signs of the projected change in each NBS component; one must also account for their relative magnitudes. The potential risk of more frequent episodes of lake levels below the low water datum, a critical shipping threshold, is explored.
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Guy, Christopher S., Thomas E. McMahon, Wade A. Fredenberg, Clinton J. Smith, David W. Garfield, and Benjamin S. Cox. "Diet Overlap of Top-Level Predators in Recent Sympatry: Bull Trout and Nonnative Lake Trout." Journal of Fish and Wildlife Management 2, no. 2 (December 1, 2011): 183–89. http://dx.doi.org/10.3996/012011-jfwm-004.
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Abstract The establishment of nonnative lake trout Salvelinus namaycush in lakes containing lacustrine–adfluvial bull trout Salvelinus confluentus often results in a precipitous decline in bull trout abundance. The exact mechanism for the decline is unknown, but one hypothesis is related to competitive exclusion for prey resources. We had the rare opportunity to study the diets of bull trout and nonnative lake trout in Swan Lake, Montana during a concomitant study. The presence of nonnative lake trout in Swan Lake is relatively recent and the population is experiencing rapid population growth. The objective of this study was to evaluate the diets of bull trout and lake trout during the early expansion of this nonnative predator. Diets were sampled from 142 bull trout and 327 lake trout during the autumn in 2007 and 2008. Bull trout and lake trout had similar diets, both consumed Mysis diluviana as the primary invertebrate, especially at juvenile stages, and kokanee Oncorhynchus nerka as the primary vertebrate prey, as adults. A diet shift from primarily M. diluviana to fish occurred at similar lengths for both species, 506 mm (476–545 mm, 95% CI) for bull trout and 495 mm (470–518 mm CI) for lake trout. These data indicate high diet overlap between these two morphologically similar top-level predators. Competitive exclusion may be a possible mechanism if the observed overlap remains similar at varying prey densities and availability.