Search results for "Lake"
showing 10 items of 369 documents
Lake Load Response (LLR) – mallityökalu vesialueiden hoidon suunnittelun apuvälineenä
2010
For eutrophic lakes, achieving good water quality usually requires a reduction in external loading. The Lake Load Response (LLR) tool, based on the LakeState (LS) model, can be used to predict the necessary loading reduction, which can be utilized when making decisions on the management of the lake. The best predictions are made when the input values of the incoming loading, water outflow and in-lake total phosphorus, total nitrogen and chlorophyll a concentrations are as accurate as possible. Accurate loading data is often hard to collect because of the lack of resources for observations. However, LLR-runs made for the lake Lehesjärvi-Vähäjärvi in Jyväskylä showed that examining the needed…
Regional variations in occupancy frequency distributions patterns between odonate assemblages in Fennoscandia
2018
Odonate (damselfly and dragonfly) species richness and species occupancy frequency distributions (SOFD) were analysed in relation to geographical location in standing waters (lakes and ponds) in Fennoscandia, from southern Sweden to central Finland. In total, 46 dragonfly and damselfly species were recorded from 292 waterbodies. Species richness decreased to the north and increased with waterbody area in central Finland, but not in southern Finland or in Sweden. Species occupancy ranged from 1 up to 209 lakes and ponds. Over 50% of the species occurred in less than 10% of the waterbodies, although this proportion decreased to the north. In the southern lakes and ponds, none of the species o…
Increasing air temperature relative to water temperature makes the mixed layer shallower, reducing phytoplankton biomass in a stratified lake
2023
The depth of the mixed layer is a major determinant of nutrient and light availability for phytoplankton in stratified waterbodies. Ongoing climate change influences surface waters through meteorological forcing, which modifies the physical structure of fresh waters including the mixed layer, but effects on phytoplankton biomass are poorly known. To determine the responses of phytoplankton biomass to the depth of the mixed layer, light availability and associated meteorological forcing, we followed daily changes in weather and water column properties in a boreal lake over the first half of a summer stratification period. Phytoplankton biomass increased with the deepening of the mixed layer …
CHOOSING OF OPTIMAL REFERENCE SAMPLES FOR BOREAL LAKE CHLOROPHYLL A CONCENTRATION MODELING USING AERIAL HYPERSPECTRAL DATA
2018
Abstract. Optical remote sensing has potential to overcome the limitations of point estimations of lake water quality by providing spatial and temporal information. In open ocean waters the optical properties are dominated by phytoplankton density, while the relationship between color and the constituents is more complicated in inland waters varying regionally and seasonally. Concerning the difficulties relating to comprehensive modeling of complex inland and coastal waters, the alternative approach is considered in this paper: the raw digital numbers (DN) recorded using aerial remote hyperspectral sensing are used without corrections and derived by means of regression modeling to predict C…
The Eminent French Chemist Claude-Louis Berthollet (1748-1822) in the Literature between the 19th and 21st Century
2020
Claude-Louis Berthollet (1748-1822) was one of the greatest French chemists of the eighteenth and the first 20 years of the nineteenth century. His life and scientific achievements were described in the literature published between the 19th and 21st centuries in different countries. The purpose of this article was to familiarize readers with the important events in the life of C.-L. Berthollet and his research activities, in particular some of his experimental research results, as well as his selected publications. In addition, the names of authors of biographies or biographical notes about Claude-Louis Berthollet, published in 1823-2018 were presented.
WATER MANAGEMENT PROBLEMS AT THE BUKÓWKA DRINKING WATER RESERVOIR’S CROSS-BORDER BASIN AREA IN TERMS OF ITS ESTABLISHED FUNCTIONS
2015
The paper covers the analysis of water management problems in the cross-border reservoir basin of Bukówka, located at the Bóbr river, at 271+540 km of its course, below the Czech-Polish border, in Dolnośląskie Voivodeship. The problems of water management in the context of the reservoir’s functions have been analyzed; these are: flood control, the provision of water during low water level periods for the Water Treatment Plant in Marciszów, the provision of drinking water for the city of Wałbrzych as well as the provision of proper flow in the Bóbr river bed downstream from the reservoir. Due to its localization right below the border with the Czech Republic, the reservoir is exposed to a nu…
Studies on the zooplankton of the deep subalpine Lake Garda
1999
The specific composition and seasonal dynamics of the zooplankton of Lake Garda have been studied through monthly surveys in two annual cycles (December 1994-November 1995 and January-December 1997). The assemblage is largely dominated by Copipo-diaptomus steueri, a typical calanoid presently identified in deep (Garda, Iseo) and shallow lakes of NE Italy and in the hinterland of the central Adriatic region (Dalmatia and Marche Region). Cladocerans and the smaller rotifers represent a significant component of the zooplankton from spring to autumn. A re-examination of the results obtained in previous studies does not seem to demonstrate substantial shifts in the composition of the dominant sp…
Bacterial and phytoplankton responses to nutrient amendments in a boreal lake differ according to season and to taxonomic resolution
2011
Nutrient limitation and resource competition in bacterial and phytoplankton communities may appear different when considering different levels of taxonomic resolution. Nutrient amendment experiments conducted in a boreal lake on three occasions during one open water season revealed complex responses in overall bacterioplankton and phytoplankton abundance and biovolume. In general, bacteria were dominant in spring, while phytoplankton was clearly the predominant group in autumn. Seasonal differences in the community composition of bacteria and phytoplankton were mainly related to changes in observed taxa, while the differences across nutrient treatments within an experiment were due to chang…
Invasive crayfish increase habitat connectivity: a case study in a large boreal lake
2013
Several studies have shown that distinct compartments of lake ecosystems are coupled via transportation of organic matter, nutrients and energy across habitat boundaries. Here we evaluate the potential of the invasive signal crayfish (Pacifastacus leniusculus (Dana)) to modify energy pathways in large boreal lakes. Using a stable isotope mixing model and calculation of the isotopic niches we estimated the contribution of different food sources to the diets of crayfish captured from different habitats, and from that inferred their potential to transport energy across the littoral-profundal gradient. The crayfish caught from the littoral area utilized mainly littoral food sources, whereas the…
Revisiting the Salt Lake City Olympic scandal: Would the outcome be different today?
2016
Many international sport organizations face bribery scandals resulting from its event bidding process. The International Olympic Committee (IOC) faced this type of scandal with the 2002 Olympic Winter Games. Two members of the Salt Lake City Organizing Committee (SLOC) faced 15 criminal charges from providing more than US$1.2 million in cash and gifts to entice IOC members to support its bid. Ultimately both SLOC members were acquitted of all charges. Can a new interpretation of the United States’ anti-bribery law, the Foreign Corrupt Practices Act (FCPA), be effective in preventing similar sport scandals? peerReviewed