scholarly journals Bacterial community analysis of the water surface layer from a rice-planted and an unplanted flooded field

2010 ◽  
Vol 41 (2) ◽  
pp. 411-419 ◽  
Author(s):  
Ana Fernández Scavino ◽  
Javier Menes ◽  
Lucía Ferrando ◽  
Silvana Tarlera
1982 ◽  
Vol 104 (1) ◽  
pp. 34-39 ◽  
Author(s):  
B. M. Howe ◽  
A. J. Chambers ◽  
S. P. Klotz ◽  
T. K. Cheung ◽  
R. L. Street

The velocity and temperature fields on both sides of an air-water interface were examined experimentally in order to understand better the physical processes of momentum and heat transfer through the surface layers about the interface. An examination of temperature and velocity profiles plotted in “law-of-the-wall” coordinates leads to the conclusion that, both in the air and in the water, the mechanism of momentum transfer is affected by surface roughness changes, but the mechanism of heat transfer is not. In the water surface layer the velocity fluctuations due to the wave-related motions are of the same order as the purely turbulent motions. The turbulent components closely resemble those found in boundary layers over solid walls. The measured total energy flux from the interface agrees well with the measured single-phase, vertical heat transport through the water surface layer.


1982 ◽  
Vol 60 (9) ◽  
pp. 2190-2197 ◽  
Author(s):  
B. M. Braune ◽  
D. E. Gaskin

A study of three species of migrating larids was undertaken off Deer Island, New Brunswick, to compare feeding methods and diving rates of birds exploiting various prey types. Bonaparte's Gulls (Larus Philadelphia) fed mainly by diving (dipping and plunging) and surface seizing, whereas Common and Arctic Terns (Sterna hirundo and S. paradisaea) acquired food by diving only. Common and Arctic Terns foraged from greater heights than Bonaparte's Gulls, and both the gulls and the terns maintained a higher foraging height while feeding on small fish than while feeding on euphausiids or, in the case of the gulls, insects. Common and Arctic Terns had a steeper dive angle than Bonaparte's Gulls, and both the gulls and the terns dove more steeply when feeding on small fish than on euphausiids. The highest diving rate occurred when Bonaparte's Gulls were dipping for insects trapped in the water surface layer. There was no significant difference in mean dipping or plunging rates between the gulls and the terns feeding on euphausiids or small fish. Bonaparte's Gulls had a lower mean rate of incomplete dives than did terns, probably because of the gulls' lesser aerial manoeuverability reducing the likelihood of altering course after dive initiation. The mean dipping rate was higher than the mean plunging rate for both the gulls and the terns since most food was taken at the surface, and plunges were necessary only for deeper prey (usually small fish). Intervals between hovering and diving were similar for both the gulls and the terns.


2003 ◽  
Vol 83 (22) ◽  
pp. 4506-4508 ◽  
Author(s):  
N. T. Cherpak ◽  
A. A. Barannik ◽  
Yu. V. Prokopenko ◽  
T. A. Smirnova ◽  
Yu. F. Filipov

2018 ◽  
Vol 478 (2) ◽  
pp. 268-273
Author(s):  
A. P. Lisitzin ◽  
V. N. Lukashin ◽  
A. N. Novigatsky ◽  
A. A. Klyuvitkin ◽  
O. M. Dara ◽  
...  

2021 ◽  
Vol 9 (2) ◽  
pp. 217 ◽  
Author(s):  
Mohammad Barzegar ◽  
Darek Bogucki ◽  
Brian K. Haus ◽  
Mingming Shao

We have carried out an experimental study of the turbulence kinetic energy dissipation rate (ϵ), temperature dissipation rate (χ), and turbulent heat flux (THF) within the water surface layer in the presence of non-breaking wave, surface convection, and horizontal heat and eddy fluxes that play a prominent role in the front. We noted that the non-breaking wave dominates ϵ values within the surface layer. While analyzing the vertical ϵ variability, the presence of a wave-affected layer from the water surface to a depth of z≈1.25λw is observed, where λw is the wavelength. ϵ associated with non-breaking waves ranged to 4.9×10−6–7×10−6 m2/s3 for the wavelength range of 0.038 m < λw < 0.098 m categorized as the gravity and gravity-capillary wave regimes. ϵ values increase for longer λw and non-breaking wave ϵ values represent their significant contribution to the ocean energy budget and dynamic of surface layer considering that the non-breaking wave covers the large fraction of ocean surface. We also found that the surface mean square slope (MSS) and wave generated ϵ have the same order of magnitude, i.e., MSS ∼ϵ. Besides, we have documented that the small-scale temperature fluctuation change (i.e., χ) is consistent with the large-scale temperature gradient change (i.e., d<T>/dz). The value of the THF is approximately constant within the surface layer. It represents that the measured THF near the water surface can be considered a surface water THF, challenging to measure directly.


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