| 1. |
- Elmberg, Johan, 1960-
(författare)
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Threats to boreal frogs
- 1993
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Ingår i: Ambio. - 0044-7447 .- 1654-7209. - 0044-7447 ; 22:4, s. 254-255
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Tidskriftsartikel (refereegranskat)
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| 2. |
- Gunnarsson, Gunnar
(författare)
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Mörbylånga hamn
- 1992
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Ingår i: Fågellokaler på Öland. - Färjestaden : Ölands ornitlogiska förening. - 9197080748
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Bokkapitel (populärvet., debatt m.m.)
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| 3. |
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| 4. |
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| 5. |
- Lacoursière, Jean O., 1958-, et al.
(författare)
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A small flume for studying the influence of hydrodynamic factors on benthic invertebrate behaviour
- 1990
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Ingår i: Journal of The North American Benthological Society. - 0887-3593 .- 1937-237X. ; 9:4, s. 358-367
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Tidskriftsartikel (refereegranskat)abstract
- A compact, versatile flume for studying the influence of hydrodynamic factors on the behaviour of benthic invertebrates is described. A range of lotic micro-environments can be simulated under controlled and replicable conditions by tailoring the velocity profile at the entrance of the test section. A specially designed diffuser composed of an array of adjustable horizontal rods allows tailored flow (e.g., zone of high shear stress, adjustable velocity gradient and turbulence level) to which organisms can be exposed. Water velocities of up to a maximum of 81.5 plus or minus 0.6 cm/s, with a turbulence intensity of 0.8% can be achieved. Simultaneous observations of flow and organism behaviours can be done by means of standard flow visualization techniques. Compact (72 cm long x 22 cm high x 10 cm wide; volume 10 L) and easily transportable, this flume is an inexpensive "desk-top" version of larger, more bulky systems, without sacrifice of performance and versatility.
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| 6. |
- Lacoursière, Jean O., 1958-, et al.
(författare)
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Fluid transmission and filtration efficiency of the labral fans of black fly larvae (Diptera: Simuliidae) : Hydrodynamic, morphological, and behavioural aspects
- 1993
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Ingår i: Canadian Journal of Zoology. - 0008-4301 .- 1480-3283. ; 71:1, s. 148-162
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Tidskriftsartikel (refereegranskat)abstract
- Body stance and water flow through the labral fans of suspension-feeding Simulium vittatum Zetterstedt larvae were examined using dead and live larvae. Transmission of flowing water through the fans were determined by means of dye injections. Feeding stance is the outcome of an active feedback process between flow forces and behavioural reactions that maintains the fans in an optimal filtering position. Fans responded to velocity increases through structural reconfiguration, which resulted in an increase in aperture size. As the velocity decreased, an increased fraction of the water directly approaching the fan aperture flowed around its perimeter, with no flow through the fans below 2.5 cm/s. Fluid transmission never exceeded 30-35%, even at velocities up to 50 cm/s. Calculations of suspension-feeding efficiency are reformulated to reflect labral fan transmission and behavioural components of the feeding process. Simulium vittatum larvae are consequently showed to be 4-26 times more efficient in filter feeding than has been previously assessed. The effect of flow on labral fan transmission is discussed in relation to known habitat choices and feeding behaviours of simuliid larvae.
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