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Allometric relations between fluvial impulse and morphometric parameters of floodplain lakes 
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下载免费PDF全文 The general role of river water input in shaping the basic morphometric parameters of floodplain lakes has been previously investigated. However, the process has not been quantitatively described in detail. This study is the first attempt in the literature to determine the allometric relation between fluvial impulse, expressed as Fluvial Connectivity Quotient, and morphometric parameters of six floodplain lakes of Bug River valley in the period 1952–2014. This relationship is given by Y = aXb, from which the value of b exponent was analysed to determine the strength of the allometric relation. Extreme values of allometric compounds during the time period under study ranged from 5.99 to ?4.91. Volume was the morphometric parameter showing the highest variability in all the lakes. General similarity in allometric relations was observed in the lakes under study. During analysis, no long‐term trends were observed in the relationship between the Fluvial Connectivity Quotient and morphometric parameters. The results obtained show that fluvial impulse was the factor determining the variability of morphometric parameters of the lakes. Direct catchments topography of lake has periodically (during limnophase periods) played a significant role in shaping the morphometry of floodplain lakes. The most stable allometric relations occurred in a confluent lake, with a low limnological effective rise value and consequently, relatively long potamophase periods.Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Patterns of hydrologic connectivity in the McMurdo Dry Valleys,Antarctica: a synthesis of 20 years of hydrologic data 下载免费PDF全文
下载免费PDF全文 Adam N. Wlostowski Michael N. Gooseff Diane M. McKnight Christopher Jaros W. Berry Lyons 《水文研究》2016,30(17):2958-2975
Streams in the McMurdo Dry Valleys (MDVs) of Antarctica moderate an important hydrologic and biogeochemical connection between upland alpine glaciers, valley‐bottom soils, and lowland closed‐basin lakes. Moreover, MDV streams are simple but dynamic systems ideal for studying interacting hydrologic and ecological dynamics. This work synthesizes 20 years of hydrologic data, collected as part of the MDVs Long‐Term Ecological Research project, to assess spatial and temporal dynamics of hydrologic connectivity between glaciers, streams, and lakes. Long‐term records of stream discharge (Q), specific electrical conductance (EC), and water temperature (T) from 18 streams were analysed in order to quantify the magnitude, duration, and frequency of hydrologic connections over daily, annual, and inter‐annual timescales. At a daily timescale, we observe predictable diurnal variations in Q, EC, and T. At an annual timescale, we observe longer streams to be more intermittent, warmer, and have higher median EC values, compared to shorter streams. Longer streams also behave chemostatically with respect to EC, whereas shorter streams are more strongly characterized by dilution. Inter‐annually, we observe significant variability in annual runoff volumes, likely because of climatic variability over the 20 record years considered. Hydrologic connections at all timescales are vital to stream ecosystem structure and function. This synthesis of hydrologic connectivity in the MDVs provides a useful end‐member template for assessing hydrologic connectivity in more structurally complex temperate watersheds. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Jarosław Zawadzki Tadeus Magiera Piotr Fabijańczyk 《Studia Geophysica et Geodaetica》2009,53(1):133-149
The goal of the study was the geostatistical evaluation of quantitative magnetic measures, which can be used for effective
delineation of the extent of the area polluted with heavy metals. Several parameters of magnetic susceptibility, measured
in the soil profile, were proposed as magnetic indicators of soil pollution and analyzed in detail. The following parameters
were calculated: maximum magnetic susceptibility, magnetic susceptibility at the depth of 3 cm and 5 cm, and the area under
the curve of magnetic susceptibility. Measurements were performed at two forested study areas, located in Upper Silesian Industrial
Area (Poland). Analyses were performed using geostatistical methods, and the results were verified using dense chemical measurements.
The results showed that the area under curve of magnetic susceptibility was the most effective magnetic indicator of soil
contamination with heavy metals. It was possible to detect the entire polluted area, and only about 16% of the study area
was assumed to be contaminated while being unpolluted. The results obtained with maximum magnetic susceptibility and magnetic
susceptibility at the depth of 3 cm and 5 cm were less effective in comparison with the area under curve of magnetic susceptibility. 相似文献
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Budzyń Bartosz Harlov Daniel E. Kozub-Budzyń Gabriela A. Majka Jarosław 《Mineralogy and Petrology》2017,111(2):183-217
Mineralogy and Petrology - The relative stabilities of phases within the two systems monazite-(Ce) – fluorapatite – allanite-(Ce) and xenotime-(Y) – (Y,HREE)-rich fluorapatite... 相似文献
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Pressure‐driven,shoreline currents in a perennially ice‐covered,pro‐glacial lake in Antarctica,identified from a LiCl tracer injected into a pro‐glacial stream 下载免费PDF全文
下载免费PDF全文 The distribution of streamwater within ice‐covered lakes influences sub‐ice currents, biological activity and shoreline morphology. Perennially ice‐covered lakes in the McMurdo Dry Valleys, Antarctica, provide an excellent natural laboratory to study hydrologic–limnologic interactions under ice cover. For a 2 h period on 17 December 2012, we injected a lithium chloride tracer into Andersen Creek, a pro‐glacial stream flowing into Lake Hoare. Over 4 h, we collected 182 water samples from five stream sites and 15 ice boreholes. Geochemical data showed that interflow travelled West of the stream mouth along the shoreline and did not flow towards the lake interior. The chemistry of water from Andersen Creek was similar to the chemistry of water below shoreline ice. Additional evidence for Westward flow included the morphology of channels on the ice surface, the orientation of ripple marks in lake sediments at the stream mouth and equivalent temperatures between Andersen Creek and water below shoreline ice. Streamwater deflected to the right of the mouth of the stream, in the opposite direction predicted by the Coriolis force. Deflection of interflow was probably caused by the diurnal addition of glacial runoff and stream discharge to the Eastern edge of the lake, which created a strong pressure gradient sloping to the West. This flow directed stream momentum away from the lake interior, minimizing the impact of stream momentum on sub‐ice currents. It also transported dissolved nutrients and suspended sediments to the shoreline region instead of the lake interior, potentially affecting biological productivity and bedform development. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Biodiversity, abundance and taxonomic composition of shallow-water zoobenthos were studied in the W?oc?awek Dam Reservoir (the lower Vistula River, central Poland). The following habitats located near the shore were studied: (1) sandy bottom in the flooded part of the reservoir; (2) sandy bottom close to the main riverine flow in the reservoir and (3) organic-rich bottom covered by a thick layer of plant remnants in a shallow, isolated cove. In each habitat we investigated two sites (ca. 0.5 and 1 m depth). Also examined was the bottom of a phytolittoral site (sandy bottom, with elodeids and nympheids, 1 m depth), located in the flooded zone. In general, the bottom fauna was highly diverse and abundant in these habitats. The highest biodiversity (38 taxa, Shannon-Wiener index=4.3) was found on the bottom rich in organic matter. However, the zoobenthos abundance in this habitat was comparatively low, probably due to periodical oxygen deficiencies. The highest density of bottom fauna (>30,000 individuals per m2), accompanied by its high biodiversity, occurred at the phytolittoral site. The benthic community of the organic-rich sediments was the most distinct, with many taxa occurring exclusively in this area. The composition of the bottom fauna, from the two sandy habitats and phytolittoral, also differed from one another. The differences in taxonomic composition between the shallower and deeper sites were less pronounced. Lower densities at the shallower sandy sites and a very high variability of taxonomic composition among particular samples from these sites indicated lower stability of their environmental conditions. These were certainly due to water level fluctuations and/or destructive wave action. On the other hand, no such differences were found between the sites of various depths from the organic-rich sediments, showing that this substratum provided better protection against adverse hydrodynamical factors. 相似文献
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Study of litter influence on magnetic susceptibility measurements of urban forest topsoils using the MS2D sensor 总被引：1，自引：1，他引：0
Jarosław Zawadzki Piotr Fabijańczyk Tadeusz Magiera Zygmunt Strzyszcz 《Environmental Earth Sciences》2010,61(2):223-230
Field magnetometry is fast and convenient method used to detect areas contaminated by technogenic magnetic particles and potentially
polluted with heavy metals. Frequently, measurements of soil magnetic susceptibility (κ) are carried out with MS2D Bartington
sensor, which penetration range equals 10 cm, although 90% of the total signal is detected from a depth of up to 6 cm. Thick
uppermost organic soil layers may significantly influence on the measured κ because the penetration range may be not large
enough to cover the layers where the most of anthropogenic contaminants are cumulated. The aim of the study was to investigate
on how the removal of the litter improves the MS2D measurements of soil pollution. Accordingly, the correlations between κ
values measured on the successively removed overlying soil sub-horizons were investigated. Measurements were performed at
15 sites located in different forest in the Upper Silesian Industrial Area, Poland. The results showed that the litter removal
enabled the MS2D to measure the κ more related to the anthropogenic pollution, and did not affect the measuring variance. 相似文献