|
|
|
|
|
| Bebars, Mi; Lasserre, G; Hoai, Tl. |
| Annually exploited communities from the Nile delta and two nearby lagoons (Manzalah and Edkou) were monitored from 1962 to 1989. The changes in community structure were analysed as a function of two events: fishing pressure growth (motorized fishing vessels) which increased by a factor of 19 between 1952 and 1962; and the construction of the Aswan Dam, which was built between 1965 and 1969, reducing the flow of the Nile by 90 %. Before the construction of the dam, increased sea fishing pressure led to a decline in landings from 33,832 tons in 1962 to 8,522 tons in 1969, but with no structural change in the exploited community. However, following completion of the dam in 1969, the community structure changed and a significant correlation was detected... |
| Tipo: Text |
Palavras-chave: Impact; Aswan Dam; Yield; Fisheries; Diversity; Lagoon. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20406/18073.pdf |
| |
|
| |
|
|
| Louis, M; Lasserre, G. |
| During the year 1980, monthly observations were made on the distribution and dynamics of fish populations in two mangrove lagoons (Belle-Plaine and Manche-a-Eau). A total of 39 species was found in the two mangrove lagoons but the maximum number observed did not exceed 19 species for each sampling. The species were separated into four main groups: (1) the sedentary species which spend their whole life in the mangrove lagoons; (2) the species only represented by juvenile individuals (the greatest group); (3) the species occurring occasionally in the mangrove lagoon; (4) the species only observed during the reproduction period. Three demographic models were tested: the models of Preston, Motomura and MacArthur. Preston better fitted the population of... |
| Tipo: Text |
|
| Ano: 1982 |
URL: http://archimer.ifremer.fr/doc/00246/35726/34234.pdf |
| |
|
|
| Santos, M; Monteiro, C; Lasserre, G. |
| The fish assemblages of two artificial reef systems of the south coast of Algarve (Portugal) are presented, and a comparative study is made of their species richness variation according to their location off the Ria Formosa lagoon. Each system consists of a protection reef and an exploitation reef. Gillnets, traps, longline and visual census were used as sampling techniques. Both reefs showed similar species richness, in each case higher than that of Ria Formosa. No significant differences of species richness were found between the reef systems (p = 0.1). However, the exploitation reefs showed a significant difference of species richness, that was more evident when accumulated species richness was used to compare them (p = 0.01). |
| Tipo: Text |
|
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00096/20764/18390.pdf |
| |
|
|
| Amanieu, M; Lasserre, G. |
| The analysis of the community structures of a Danish fjord macrofauna and of various Mediterranean lagoons results in the same interpretation of the organization of communities which start from meroplankton, leading to the formation of disorganized communities. The biotic and abiotic lagoon environment puts these populations under stress, causing gradual organization into structured one-species communities. Such an interpretation suggests that the degree of organization is measured by the species diversity or more precisely by one species alone. Each population has to develop and adapt strategy which favors migratory behavior. When this is not possible, a waste economy develops where the speed of the generation cycles corrects the catastrophic losses... |
| Tipo: Text |
|
| Ano: 1982 |
URL: http://archimer.ifremer.fr/doc/00246/35752/34260.pdf |
| |
|
| |
|
|
| Aliaume, C; Monteiro, C; Louis, M; Hoai, Tl; Lasserre, G. |
| Fish communities from two lagoon ecosystems, Ria Formosa (Portugal) and Grand Cul-de-Sac Marin (Guadeloupe), show interesting similarities of spatial and temporal organization. On the temporal scale, three community changes are observed in both systems, corresponding to massive arrivals and/or departures of migratory species. However, these migrations are more conspicuous in the Ria Formosa than in the Grand Cul-de-Sac Marin. On a spatial scale, the community structure is also largely determined by migratory species, whose abundance is a factor of homogenization. This is clearly observed in Ria Formosa, where the lagoon selection applies on a regional scale. Conversely, the community of sedentary fish identifies remarkable stations affected by chronic... |
| Tipo: Text |
Palavras-chave: COMMUNITIES; FISH ASSEMBLAGES; LAGOONS; CARIBBEAN; PORTUGAL. |
| Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00099/21056/18682.pdf |
| |
|
| |
|
|
|
