Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8492997 | Aquaculture | 2018 | 28 Pages |
Abstract
The first assay tested a factorial combination of light colors (blue vs white) and intensity (low ~13â¯lx (36â¯W/m2), medium ~87â¯lx (151â¯W/m2) and high ~265â¯lx (422â¯W/m2)). The results pointed to a significant negative impact of low light intensities (13 and 87â¯lx) on paralarval growth. The second assay was designed to contrast light colors (blue vs white), different levels of intensities (300â¯lx (478â¯W/m2) vs 600â¯lx (1077â¯W/m2)) and partial coverage of the tanks using a shade mesh, named as “shadow zone” (half-covered vs non-covered tanks). In half-covered tanks, survival was significantly improved, with the best results coming from half-covered tanks with blue light and 600â¯lx, but no differences in dry weight were observed. The third experiment tested a factor called “light source position” with two levels: “Control” when the light incidence angle was 0° with respect to the normal direction (i.e. perpendicular to the water surface), and “Oblique” when the light incidence angle was 60° with respect to the normal direction. In this experiment, survival significantly improved under oblique light but no differences in dry weight were detected. The last experiment was an unifactorial design combining “light source position” and “tank partial coverage” with three treatments: i) control light with uncovered tanks, ii) oblique light with uncovered tanks, iii) control light with semi-covered tanks. Oblique light with uncovered tanks was associated with a higher survival rate but without statistical significance, probably due to data variability. It can be concluded that light intensity tended to affect paralarval dry weight, whereas the existence of a shadow zone or oblique light are more related with an improvement of survival rates.
Related Topics
Life Sciences
Agricultural and Biological Sciences
Aquatic Science
Authors
R. Tur, Á. Roura, L. Márquez, C. López, M.J. Lago, M. MallorquÃn, E. Almansa,