Éditeur(s) : Kluwer
Résumé : We reviewed the literature concerning fish aggregation devices (FADs) to determine areas of relative research deficiency. Using specific searches of the Aquatic Sciences and Fisheries Abstracts ( ASFA) database from 1978 to December 2003 and a classical search of the pre-1978 literature, we collected 407 references on FADs. Publications before 1980 were predominantly peer-reviewed, although non-peer reviewed literature has dominated since 1980, due to the numerous technical reports produced as FADs became more widely used in artisinal and large-scale industrial. sheries in the 1980s. Most studies of the ecology of FAD-associated fish were descriptive, with few mensurative experimental studies and even fewer manipulative experimental studies that tested specific hypotheses, due to inherent difficulties in working in the open ocean on objects that are temporary in space and time. Research on the ecology of FAD-associated fish has focused on moored FADs, despite the major FAD-based. sheries being around drifting FADs. Publications presenting information on moored FADs outnumbered papers on drifting FADs by a ratio of 3.5: 1. We recommend that greater emphasis be placed by. sheries scientists and funding agencies on researching drifting FADs to provide better information for management of large-scale FAD-based industrial. sheries. Future research should focus on determining the patterns of use of drifting FADs by pelagic species, the underlying sensory processes of attraction and the ecological consequences for individual fish stocks and the wider pelagic ecosystem of the use of FADs as. sheries enhancement tools.
Reviews in Fish Biology and Fisheries (0960-3166) (Kluwer), 2004-03 , Vol. 14 , N. 1 , P. 21-42

Droits : 2004 Springer
http://archimer.ifremer.fr/doc/2004/publication-721.pdf
DOI:10.1007/s11160-004-3151-x
http://archimer.ifremer.fr/doc/00000/721/

Éditeur(s) : HAL CCSD Kluwer
Résumé : This paper presents some considerations about hybrid optimization algorithms useful to optimize real complex system. The given indication could be used by readers to conceive hybrid algorithms. These considerations have been deducted from a concrete application case: the satellites constellations design problem. But each of the advanced techniques proposed in this paper are considered in a more general way to solve other problems. This problem is used to illustrate the techniques along the paper because it is grouping many characteristics (di culties) of contemporary real complex systems: the size and the characteristics of the search space engendered by a combinatorial problem; The irregularity of the criterions; The mathematical and physical heterogeneity of parameters forbids the use of classical algorithms; The evaluation of a solution, which uses a time consuming simulation; A need of accurate values. More details are available in previous papers ([?], [?], [?], [?]). For these reasons, we could learn a lot from this experiment in order to detach hybrid techniques usable for problems having close characteristics. This paper presents the historic leading to the current algorithm, the modeling of the complex system and the sophisticated algorithm proposed to optimize it. Application cases and ways to built signi cant tests of hybrid algorithm are also given.
International Federation for Information Processing

hal-00602279
https://hal.archives-ouvertes.fr/hal-00602279

Éditeur(s) : HAL CCSD Kluwer Academic Publishers
Résumé : International audience
The interlocking leaves of tank-forming bromeliads (Bromeliaceae) collect rainwater and detritus, thus creating a freshwater habitat for specialized organisms. Their abundance and the possibility of quantifying communities with accuracy give us unparalleled insight into how changes in local to regional environments influence community diversity in small water bodies. We sampled 365 bromeliads (365 invertebrate communities) along a southeastern to northwestern range in French Guiana. Geographic locality determined the species pool for bromeliad invertebrates, and local environments determined the abundance patterns through the selection of traits that are best adapted to the bromeliad habitats. Patterns in community structure mostly emerged from patterns of predator species occurrence and abundance across local-regional environments, while the set of detritivores remained constant. Water volume had a strong positive correlation with invertebrate diversity, making it a biologically relevant measure of the pools' carrying capacity. The significant effects of incoming detritus and incident light show that changes in local environments (e.g., the conversion of forest to cropping systems) strongly influence freshwater communities. Because changes in local environments do not affect detritivores and predators equally, one may expect functional shifts as sets of invertebrates with particular traits are replaced or complemented by other sets with different traits.
Hydrobiologia

hal-00845572
https://hal.archives-ouvertes.fr/hal-00845572