Estuarine Residency and Migration of Southern Flounder Inferred from Conventional Tag Returns at Multiple Spatial Scales

Abstract This study aims at defining a methodology to evaluate Ks reductions of gravel material constituting constructed wetland (CW) bed matrices. Several schemes and equations for the Lefranc's test were compared by using different gravel sizes and at multiple spatial scales. The falling-head test method was implemented by using two steel permeameters: one impervious (IMP) and one pervious (P) on one side. At laboratory scale, mean K values for a small size gravel (8–15 × 10−2 m) measured by the IMP and the P permeameters were equal to 19,466 m/d and 30,662 m/d, respectively. Mean Ks values for a big size gravel (10–25 × 10−2 m) measured by the IMP and the P permeameters were equal to 12,135 m/d and 20,866 m/d, respectively. Comparison of Ks values obtained by the two permeameters at laboratory scale as well as a sensitivity analysis and a calibration, lead to the modification of the standpipe equation, to evaluate also the temporal variation of the horizontal Ks. In particular, both permeameters allow the evaluation of the Ks decreasing after 4 years-operation and 1–1.5 years' operation of the plants at full scale (filled with the small size gravel) and at pilot scale (filled with the big size gravel), respectively.

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FORMULATION OF THE HEAT CONDUCTION EQUATION FOR HETEROGENEOUS MEDIA WITH MULTIPLE SPATIAL SCALES USING REITERATED HOMOGENIZATION

Revista de Engenharia Térmica ◽

10.5380/reterm.v15i1.62165 ◽

2016 ◽

Vol 15 (1) ◽

pp. 96

Author(s):

E. Iglesias-Rodríguez ◽

M. E. Cruz ◽

J. Bravo-Castillero ◽

R. Guinovart-Díaz ◽

R. Rodríguez-Ramos ◽

...

Keyword(s):

Heat Conduction ◽

Small Parameter ◽

Heat Conduction Equation ◽

Heterogeneous Media ◽

Spatial Scales ◽

Conduction Equation ◽

Small Scale ◽

Multiple Spatial Scales ◽

Effective Coefficients ◽

Reiterated Homogenization

Heterogeneous media with multiple spatial scales are finding increased importance in engineering. An example might be a large scale, otherwise homogeneous medium filled with dispersed small-scale particles that form aggregate structures at an intermediate scale. The objective in this paper is to formulate the strong-form Fourier heat conduction equation for such media using the method of reiterated homogenization. The phases are assumed to have a perfect thermal contact at the interface. The ratio of two successive length scales of the medium is a constant small parameter ε. The method is an up-scaling procedure that writes the temperature field as an asymptotic multiple-scale expansion in powers of the small parameter ε . The technique leads to two pairs of local and homogenized equations, linked by effective coefficients. In this manner the medium behavior at the smallest scales is seen to affect the macroscale behavior, which is the main interest in engineering. To facilitate the physical understanding of the formulation, an analytical solution is obtained for the heat conduction equation in a functionally graded material (FGM). The approach presented here may serve as a basis for future efforts to numerically compute effective properties of heterogeneous media with multiple spatial scales.

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Length Variation in Age-0 Westslope Cutthroat Trout at Multiple Spatial Scales

North American Journal of Fisheries Management ◽

10.1577/m07-120.1 ◽

2008 ◽

Vol 28 (5) ◽

pp. 1529-1540 ◽

Cited By ~ 5

Author(s):

Kathleen E. McGrath ◽

J. Michael Scott ◽

Bruce E. Rieman

Keyword(s):

Spatial Scales ◽

Cutthroat Trout ◽

Length Variation ◽

Westslope Cutthroat Trout ◽

Multiple Spatial Scales

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Implications of temporal and spatial scale for Atlantic salmon (Salmo salar) research

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/d98-017 ◽

1998 ◽

Vol 55 (S1) ◽

pp. 9-21 ◽

Cited By ~ 43

Author(s):

Carol L Folt ◽

Keith H Nislow ◽

Mary E Power

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Multiple Scales ◽

Spatial Scales ◽

Effective Means ◽

Research Strategies ◽

Atlantic Salmon Salmo Salar ◽

Temporal And Spatial ◽

And Migration ◽

Dependent Processes

The Atlantic salmon (Salmo salar) is a model species for studying scale issues (i.e., the extent, duration, and resolution of a study or natural process) in ecology. Major shifts in behavior and habitat use over ontogeny, along with a relatively long life span and large dispersal and migration distances, make scale issues critical for effective conservation, management, and restoration of this species. The scale over which a process occurs must be linked to the research design and we illustrate this with a discussion of resource tracking by Atlantic salmon. Identifying scale inconsistencies (e.g., when a process is evident at one scale but not another) is shown to be an effective means by which some scale-dependent processes are understood. We review the literature to assess the temporal and spatial scales used in Atlantic salmon research and find most current studies appear to sacrifice spatial and temporal extent for increased resolution. Finally, we discuss research strategies for expanding the temporal and spatial scales in salmon research, such as conducting multiple scales studies to elucidate scale inconsistencies, identifying mechanisms, and using techniques and approaches to generalize across studies and over time and space.

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