| 1. |
- Andersen, K. H., et al.
(författare)
-
Characteristic Sizes of Life in the Oceans, from Bacteria to Whales
- 2016
-
Ingår i: Annual Review of Marine Science. - : Annual Reviews. - 1941-1405 .- 1941-0611. - 9780824345082 ; 8, s. 217-241
-
Tidskriftsartikel (refereegranskat)abstract
- The size of an individual organism is a key trait to characterize its physiology and feeding ecology. Size-based scaling laws may have a limited size range of validity or undergo a transition from one scaling exponent to another at some characteristic size. We collate and review data on size-based scaling laws for resource acquisition, mobility, sensory range, and progeny size for all pelagic marine life, from bacteria to whales. Further, we review and develop simple theoretical arguments for observed scaling laws and the characteristic sizes of a change or breakdown of power laws. We divide life in the ocean into seven major realms based on trophic strategy, physiology, and life history strategy. Such a categorization represents a move away from a taxonomically oriented description toward a trait-based description of life in the oceans. Finally, we discuss life forms that transgress the simple size-based rules and identify unanswered questions.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Green, S., et al.
(författare)
-
Escape responses of copepod nauplii in the flow field of the blue mussel, Mytilus edulis
- 2003
-
Ingår i: Marine Biology. - 0025-3162. ; 142:4, s. 727-733
-
Tidskriftsartikel (refereegranskat)abstract
- Bivalves are important grazers on phyto-plankton in shallow waters. However, very little is known about their ability to capture actively moving zooplankton. We investigated the escape response and success of early and late nauplii of three copepod species (Acartia tonsa, Temora longicornis and Eurytemora affinis) in the flow field of a blue mussel, Mytilus edulis, using both video observations and incubation experiments. An empirical model was created to describe the spatial distribution of the fluid deformation rate. Nauplii responded with escape jumps at mean fluid deformation rates of 0.6-1.9 s(-1). Escape success differed between taxa. T. longicornis was the poorest escaper, while A. tonsa and E. affinis were more efficient and similar to one another. Deformation rates differed in different parts of the flow field, which resulted in differences in escape success between the sectors. Nauplii were caught most often in the sector furthest away from the exhalent siphon, where the deformation rate was the weakest. There the nauplii were unable to detect an escape signal in time to react and flee.
|
|
| 5. |
- Hustad, J.E., et al.
(författare)
-
Reactivity measurements of coke particles in five different flow reactors
- 1990
-
Ingår i: Rivista dei Combustibili. - 0370-5463. ; 44:10, s. 257-267
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Experiments on reactivity of 128 μm coke particles in the gas temperature range from 1150 K to 1370 K have been performed in five different flow reactors in the Nordic countries and all the results were calculated by the shrinking particle model. The activation energy is found to be 25 kcal/mol indicating combustion control by the combined effects of chemical kinetic and pore diffusion (zone II combustion). The overall apparent reaction order was found to be 1.0
|
|
| 6. |
- Jaspers, C., et al.
(författare)
-
Reproduction rates under variable food conditions and starvation in Mnemiopsis leidyi: significance for the invasion success of a ctenophore
- 2015
-
Ingår i: Journal of Plankton Research. - : Oxford University Press (OUP). - 0142-7873 .- 1464-3774. ; 37:5, s. 1011-1018
-
Tidskriftsartikel (refereegranskat)abstract
- The ctenophore Mnemiopsis leidyi is characterized by high growth rates and a large reproductive capacity. However, reproductive dynamics are not yet well understood. Here, we present laboratory data on food-dependent egg production in M. leidyi and egg hatching time and success. Further, we report on the reproduction of laboratory-reared and field-caught animals during starvation. Our results show that the half-saturation zooplankton prey concentration for egg production is reached at food levels of 12-23 mu gC L-1, which is below the average summer food concentration encountered in invaded areas of northern Europe. Furthermore, starved animals continue to produce eggs for up to 12 days after cessation of feeding with high overall hatching success of 65-90%. These life history traits allow M. leidyi to thrive and reproduce in environments with varying food conditions and give it a competitive advantage under unfavourable conditions. This may explain why recurrent population blooms are observed and sustained in localized areas in invaded northern Europe, where water exchange is limited and zooplankton food resources are quickly depleted by M. leidyi. We suggest that these reproductive life history traits are key to its invasion success.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Kiorboe, T., et al.
(författare)
-
Intensive aggregate formation with low vertical flux during an upwelling-induced diatom bloom
- 1998
-
Ingår i: Limnology and Oceanography. - 0024-3590. ; 43:1, s. 104-116
-
Tidskriftsartikel (refereegranskat)abstract
- The surfaces of most pelagic diatoms are sticky at times and may therefore form rapidly settling aggregates by physical coagulation. Stickiness and aggregate formation may be particularly adaptive in upwelling systems by allowing the retention of diatom populations in the vicinity of the upwelling center. We therefore hypothesized that upwelling diatom blooms are terminated by aggregate formation and rapid sedimentation. We monitored the development of a maturing diatom (mainly Chaetoceros spp.) bloom in the Benguela upwelling current during 7 d in February. Chlorophyll concentrations remained consistently high during the observation period (similar to 500 mg Chi m(-2)) and phytoplankton grew at an average specific rate of 0.25 d(-1). The diatoms were extraordinarily sticky, with stickiness coefficients of up to 0.40, which is the highest ever recorded for field populations. Combined with estimates of turbulent shear in the ocean such stickiness coefficients predict very high specific coagulation rates (0.3 d(-1)). In situ video observation demonstrated the occurrence of abundant diatom aggregates with surface water concentrations between 1,000 and 3,000 ppm. Despite the very high concentration of aggregates, vertical fluxes of phytoplankton were very low, with fractional losses <0.005 d(-1), and the aggregates thus seemed to be near neutrally buoyant. Losses due to copepod grazing were also low (similar to 0.025 d(-1)). Most of the aggregates were colonized by the heterotrophic dinoflagellate Noctiluca scintillans that feed upon diatoms in the aggregates. The system appeared to be in near steady state; specific diatom growth rate, coagulation rate, and loss rate due to N, scintillans feeding were all of the same magnitude (0.25-0.3 d(-1)) and the latter two varied in concert. Our observations provide only partial support for the population retention hypothesis because aggregate buoyancy and N, scintillans grazing efficiently reduced the vertical flux of aggregates in this system.
|
|
| 10. |
|
|
