966 resultados para Lake Geneva


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Twelve Mile Creek Lake is a 660 acre, Significant Publicly Owned Lake with a watershed of 14,820 acres for a ratio of 21:3. The watershed is predominately privately owned agricultural land that originates in Adair County and drains into the lake which serves as the primary source water for the City of Creston, Union County and the seven counties served by the Southern Iowa Rural Water Association. In recent years, frequent algae blooms and recurrent spikes in suspended solid concentrations have been inflating water treatment expenses for the Creston Municipal Utilities (CMU). Declining trends in water quality spurred CMU to enlist the Union Soil and Water Conservation District (SWCD) to assist in evaluating watershed conditions for potential upland improvements. Significant gully erosion issues that had been previously underestimated were discovered during this watershed assessment process. Newly acquired LiDAR elevation data readily revealed this concern which was previously obscured from view by the dense tree canopy. A Watershed Development and Planning Assistance Grant Application was approved and funded by the Iowa Department of Ag and Land Stewardship- Division of Soil Conservation. Throughout the planning process, project partners innovatively evaluated and prioritized a number of resource concerns throughout the watershed. The implementation plan presented will thwart these threats which left unaided will continue to diminish the overall health of the system, reduce the appeal of the lake to recreational users, and contribute to higher water treatment costs.

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Species richness and geographical phenotypic variation in East African lacustrine cichlids are often correlated with ecological specializations and limited dispersal. This study compares mitochondrial and microsatellite genetic diversity and structure among three sympatric rock-dwelling cichlids of Lake Tanganyika, Eretmodus cyanostictus, Tropheus moorii, and Ophthalmotilapia ventralis. The species represent three endemic, phylogenetically distinct tribes (Eretmodini, Tropheini, and Ectodini), and display divergent ecomorphological and behavioral specialization. Sample locations span both continuous, rocky shoreline and a potential dispersal barrier in the form of a muddy bay. High genetic diversity and population differentiation were detected in T. moorii and E. cyanostictus, whereas much lower variation and structure were found in O. ventralis. In particular, while a 7-km-wide muddy bay curtails dispersal in all three species to a similar extent, gene flow along mostly continuous habitat appeared to be controlled by distance in E. cyanostictus, further restricted by site philopatry and/or minor habitat discontinuities in T. moorii, and unrestrained in O. ventralis. In contrast to the general pattern of high gene flow along continuous shorelines in rock-dwelling cichlids of Lake Malawi, our study identifies differences in population structure among stenotopic Lake Tanganyika species. The amount of genetic differentiation among populations was not related to the degree of geographical variation of body color, especially since more phenotypic variation is observed in O. ventralis than in the genetically highly structured E. cyanostictus.

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Agreed-upon procedures report on the City of Wall Lake, Iowa for the period July 1, 2014 through June 30, 2015

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Summary of lake water quality data collected in 2014 as part of the Iowa DNR's lake monitoring program.

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Summary of lake water quality data collected from 2000 through 2014 for lakes statewide monitored as part of the Iowa DNR's lake monitoring program.

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The deposition of Late Pleistocene and Holocene sediments in the high-altitude lake Meidsee (located at an altitude of 2661 m a.s.l. in the Southwestern Alps) strikingly coincided with global ice-sheet and mountain-glacier decay in the Alpine forelands and the formation of perialpine lakes. Radiocarbon ages of bottom-core sediments point out (pre-) Holocene ice retreat below 2700 m a.s.l., at about 16, 13, 10, and 9 cal. kyr BP. The Meidsee sedimentary record therefore provides information about the high-altitude Alpine landscape evolution since the Late Pleistocene/Holocene deglaciation in the Swiss Southwestern Alps. Prior to 5 cal. kyr BP, the C/N ratio and the isotopic composition of sedimentary organic matter (delta N-15(org), delta C-13(org)) indicate the deposition of algal-derived organic matter with limited input of terrestrial organic matter. The early Holocene and the Holocene climatic optimum (between 7.0 and 5.5 cal. kyr BP) were characterized by low erosion (decreasing magnetic susceptibility, chi) and high content of organic matter (C-org > 13 wt.%), enriched in C-13(org) (>-18 parts per thousand) with a low C/N (similar to 10) ratio, typical of modern algal matter derived from in situ production. During the late Holocene, there was a long-term increasing contribution of terrestrial organic matter into the lake (C/N > 11), with maxima between 2.4 and 0.9 cal. kyr BP. A major environmental change took place 800 years ago, with an abrupt decrease in the relative contribution of terrestrial organic material into the lake compared with aquatic organic material which subsequently largely dominated (C/N drop from 16 to 10). Nonetheless, this event was marked by a rise in soil erosion (chi), in nutrients input (N and P contents) and in anthropogenic lead deposition, suggesting a human disturbance of Alpine ecosystems 800 years ago. Indeed, this time period coincided with the migration of the Walser Alemannic people in the region, who settled at relatively high altitude in the Southwestern Alps for farming and maintaining Alpine passes.

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The main physical long-scale processes occurring in Lake Banyoles are reviewed as a tribute to Prof. Margalef. These processesinclude the water fluxes below the surface of the lake, the behavior of the sediment in suspension in the basins, the heat fluxesat the surface and at the bottom layers, the internal seiching, the formation of a baroclinic current due to differences in coolingbetween the two lobes, the mixing dynamics, the meromictic behavior of some of the basins and the formation and dynamics of hydrothermal plumes

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In lentic water bodies, such as lakes, the water temperature near the surface typically increases during the day, and decreases during the night as a consequence of the diurnal radiative forcing (solar and infrared radiation). These temperature variations penetrate vertically into the water, transported mainly by heat conduction enhanced by eddy diffusion, which may vary due to atmospheric conditions, surface wave breaking, and internal dynamics of the water body. These two processes can be described in terms of an effective thermal diffusivity, which can be experimentally estimated. However, the transparency of the water (depending on turbidity) also allows solar radiation to penetrate below the surface into the water body, where it is locally absorbed (either by the water or by the deployed sensors). This process makes the estimation of effective thermal diffusivity from experimental water temperature profiles more difficult. In this study, we analyze water temperature profiles in a lake with the aim of showing that assessment of the role played by radiative forcing is necessary to estimate the effective thermal diffusivity. To this end we investigate diurnal water temperature fluctuations with depth. We try to quantify the effect of locally absorbed radiation and assess the impact of atmospheric conditions (wind speed, net radiation) on the estimation of the thermal diffusivity. The whole analysis is based on the results of fiber optic distributed temperature sensing, which allows unprecedented high spatial resolution measurements (∼4 mm) of the temperature profile in the water and near the water surface.

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A sedimentary and micropaleontological study of the Quillagua Formation provides a detailed paleohydrological reconstruction of the lacustrine system which occupied the present-day hyperarid Quillagua-Llamara fore-arc Basin (Northern Chile) from lattermost Miocene to Early Pliocene times.

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Place branding is not a new phenomenon. The emphasis placed on place branding has recently become particularly strong and explicit to both practitioners and scholars, in the current context of a growing mobility of capital and people. On the one hand, there is a need for practitioners to better understand place brands and better implement place branding strategies. In this respect, this domain of study can be currently seen as 'practitioner led', and in this regard many contributions assess specific cases in order to find success factors and best practices for place branding. On the other hand, at a more analytical level, recent studies show the complexity of the concept of place branding and argue that place branding works as a process including various stakeholders, in which culture and identity play a crucial role. In the literature, tourists, companies and residents represent the main target groups of place branding. The issues regarding tourists and companies have been examined since long by place promoters, location branders, economists or other scholars. However, the analysis of residents' role in place branding has been overlooked until recently and represents a new interest for researchers. The present research aims to further develop the concept of place branding, both theoretically and empirically. First of all, the paper presents a theoretical overview of place branding, from general basic questions (definition of place, brand and place brand) to specific current debates of the literature. Subsequently, the empirical part consists in a case study of the Grand Genève (Great Geneva).