Spatiotemporal variations of wetland backscatter: The role of water depth and vegetation characteristics in Sentinel-1 dual-polarization SAR observations

Rubber bearings are widely used in bridge structures. The aqueduct structures are water bridges, so rubber bearings are often set at the end of the aqueducts. Rubber bearing cannot solve the problems such as temperature stress and supporting inhomogeneous settlement, but also play role of isolation damping. This paper mainly studies on the effects of the water-depth with changing rubber bearing on the seismic performance of the aqueduct-water coupling structure by numerical analysis.

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The Role of C-band Dual Polarization Radars for GPM Ground Validation

2006 IEEE International Symposium on Geoscience and Remote Sensing ◽

10.1109/igarss.2006.13 ◽

2006 ◽

Author(s):

E. Gorgucci ◽

L. Baldini ◽

V. Chandrasekar

Keyword(s):

Dual Polarization ◽

Ground Validation

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Feeding and overwintering of Antarctic krill across its major habitats: The role of sea ice cover, water depth, and phytoplankton abundance

Limnology and Oceanography ◽

10.4319/lo.2014.59.1.0017 ◽

2014 ◽

Vol 59 (1) ◽

pp. 17-36 ◽

Cited By ~ 47

Author(s):

Katrin Schmidt ◽

Angus Atkinson ◽

David W. Pond ◽

Louise C. Ireland

Keyword(s):

Sea Ice ◽

Water Depth ◽

Antarctic Krill ◽

Ice Cover ◽

Phytoplankton Abundance

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The effect of fire on habitat selection of mammalian herbivores: the role of body size and vegetation characteristics

Journal of Animal Ecology ◽

10.1111/1365-2656.12221 ◽

2014 ◽

Vol 83 (5) ◽

pp. 1196-1205 ◽

Cited By ~ 32

Author(s):

Stephanie L. Eby ◽

T. Michael Anderson ◽

Emilian P. Mayemba ◽

Mark E. Ritchie

Keyword(s):

Body Size ◽

Habitat Selection ◽

Mammalian Herbivores ◽

Vegetation Characteristics ◽

Selection Of

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Water physicochemistry and benthic macroinvertebrate communities in a tropical reservoir: The role of water level fluctuations and water depth

Limnologica ◽

10.1016/j.limno.2015.10.002 ◽

2015 ◽

Vol 55 ◽

pp. 13-20 ◽

Cited By ~ 5

Author(s):

Francis S. Magbanua ◽

Nikki Yvette B. Mendoza ◽

Christine Jewel C. Uy ◽

Christoph D. Matthaei ◽

Perry S. Ong

Keyword(s):

Water Level ◽

Water Depth ◽

Water Level Fluctuations ◽

Benthic Macroinvertebrate ◽

Macroinvertebrate Communities ◽

Tropical Reservoir

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Landscape control of uranium and thorium in boreal streams – spatiotemporal variability and the role of wetlands

Biogeosciences Discussions ◽

10.5194/bgd-9-2823-2012 ◽

2012 ◽

Vol 9 (3) ◽

pp. 2823-2849 ◽

Cited By ~ 2

Author(s):

F. Lidman ◽

C. M. Mörth ◽

H. Laudon

Keyword(s):

Boreal Forest ◽

Gamma Spectrometry ◽

Spatiotemporal Variability ◽

Forest Landscape ◽

Spatiotemporal Variations ◽

Forest Region ◽

Boreal Streams ◽

Landscape Control ◽

Boreal Forest Region

Abstract. The concentrations of uranium and thorium in ten partly nested streams in the boreal forest region were monitored over a two-year period. Considerable spatiotemporal variations were observed, with little or no correlation between streams. The export of both uranium and thorium varied substantially between the subcatchments, ranging from 1.7 to 30 g km−2 a−1 for uranium and from 3.2 to 24 g km−2 a−1 for thorium. Airborne gamma spectrometry was used to measure the concentrations of uranium and thorium in surface soils throughout the catchment, but could not explain the variability in the export. Instead, the extent of lakes and mires within each subcatchment was found to be a stronger predictor for the transport of uranium and thorium. The results indicate that there is a predictable and systematic accumulation of both uranium and thorium in boreal mires. Approximately 65–80 % of uranium and 55–65 % of thorium entering a mire is estimated to be retained in the peat. Overall, accumulation in mires and other types of wetlands is estimated to decrease the fluxes of uranium and thorium from the boreal forest landscape by 30–40 %. The atmospheric deposition of uranium and thorium was also quantified and its contribution to boreal streams was found to be low compared to weathering.

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La végétation des combes à neige du golfe de Richmond, Québec nordique

Canadian Journal of Botany ◽

10.1139/b86-207 ◽

1986 ◽

Vol 64 (8) ◽

pp. 1515-1524 ◽

Cited By ~ 6

Author(s):

Hubert Morin ◽

Serge Payette

Keyword(s):

Principal Component Analysis ◽

Altitudinal Gradient ◽

Principal Component ◽

Hudson Bay ◽

Snow Melt ◽

Principal Factors ◽

Vegetation Characteristics ◽

Abiotic Variables

An exhaustive survey of snow patches, along an altitudinal gradient situated in an area of about 10 km2 along the Hudson Bay highlands, underlines the role of altitude, exposition, and topography in maintaining these habitats. The principal component analysis from a stratified sampling of the snow patches in the three cuesta lithological zones (arkose, dolomite, and basalt) stresses the effect of the snow melt gradient on species distribution within a snow patch. The ordination of abiotic variables performed on the ordination frame of snow patches shows that lithology and substratum are the principal factors responsible for the vegetation characteristics, allowing the determination of two main types of snow patches in the arkose and dolomite zones and three types in the basalt zone.

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Broad-scale mercury bioaccumulation patterns in two freshwater sport fishes: testing the role of growth dilution in a warming climate

10.1101/280107 ◽

2018 ◽

Author(s):

Shyam M. Thomas ◽

Stephanie J. Melles ◽

Satyendra P. Bhavsar

Keyword(s):

Northern Pike ◽

Space Time ◽

Spatiotemporal Variations ◽

Latitudinal Zone ◽

Space And Time ◽

Spatiotemporal Trends ◽

Warming Climate ◽

Mercury Bioaccumulation ◽

Broad Scale

AbstractSport fishes at the apex of aquatic food webs are indicators of mercury in the environment. However bioaccumulation of mercury in fish is a complex process that varies in space and time. Both large-scale climatic and environmental, as well as biological factors are drivers of these space-time variations. In this study, we avail a long-running monitoring program from Ontario, Canada to better understand spatiotemporal variations in fish mercury bioaccumulation. Focussing on two common large-bodied fishes (Walleye and Northern Pike), the data were first stratified by latitudinal zone (north, mid, and south) and eight temporal periods (between 1975 & 2015). A series of linear mixed-effects models (LMEMs) with latitudinal zone, time period, and their interactions as random effects were used to capture the spatial, temporal, and spatiotemporal variations in mercury bioaccumulation. The random slopes from the best-fitting LMEM were used to define bioaccumulation index and capture trends in space and time. Given the generally warming climate trend over the past 45 years, the role of growth dilution in modulating the bioaccumulation trends was also evaluated. The full model comprising of space, time and space-time interactions was the best-fit with interaction effects explaining most of the variation. Spatiotemporal trends showed overall similar patterns for both species. Growth dilution in conjunction with estimated rates of warming for different latitudinal zones failed to explain the spatiotemporal trends. Temporal trends showed contrasting bioaccumulation patterns-increasing in Northern Pike and decreasing in Walleye, suggesting temperature-driven growth dilution is more likely in latter. However, a space-for-time substitution revealed only a weak presence of growth dilution in Walleye, and it was not attributable to temperature differences. Overall, our study summarizes broad-scale variations in fish mercury and explores the role of growth dilution in shaping the observed patterns.

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Varve Distribution Reveals Spatiotemporal Hypolimnetic Hypoxia Oscillations During the Past 200 Years in Lake Lehmilampi, Eastern Finland

Quaternary ◽

10.3390/quat2020020 ◽

2019 ◽

Vol 2 (2) ◽

pp. 20 ◽

Cited By ~ 4

Author(s):

Sarianna Salminen ◽

Saija Saarni ◽

Mira Tammelin ◽

Yu Fukumoto ◽

Timo Saarinen

Keyword(s):

Climatic Factors ◽

Sediment Cores ◽

Boreal Lakes ◽

Water Volume ◽

Spatiotemporal Variations ◽

The Past ◽

Hypoxic Water ◽

The Relationship ◽

Eastern Finland

We investigated 34 sediment cores to reconstruct spatiotemporal variations in hypolimnetic hypoxia for the past 200 years in Lehmilampi, a small lake in Eastern Finland. As hypoxia is essential for varve preservation, spatiotemporal changes in varve distribution were used as an indicator for hypolimnetic hypoxia oscillations. The hypoxic water volume was used as a variable reflecting hypolimnetic hypoxia and determined for each year by estimating the water volume beneath the water depth where shallowest varves were preserved. As a result, seven hypoxia periods, highlighting the variations in hypolimnetic hypoxia, are established. These periods may be influenced by bioturbation, lake infill, and lake level changes. Furthermore, we evaluated the relationship between hypolimnetic hypoxia oscillations and climatic factors. Diatom assemblage changes were also analyzed to estimate whether the hypoxia periods could be related to anthropogenic eutrophication. The diatom analyses suggest relatively stable nutrient conditions for the past 200 years in Lake Lehmilampi. Climate, on the other hand, seems to be an important driver of hypoxia oscillations based on correlation analysis. The role of individual forcing factors and their interaction with hypolimnetic hypoxia would benefit from further investigations. Understanding climatic and anthropogenic forcing behind hypolimnetic hypoxia oscillations is essential when assessing the fate of boreal lakes in a multi-stressor world.

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