44 resultados para Cordon littoral
em Aquatic Commons
Determination of direction of littoral transport along the north shore of Santa Rosa Island, Florida
Resumo:
The purpose of this study was to determine the actual direction of littoral transport along the north shore of Santa Rosa Island in the vicinity of Pensacola Beach, Florida. To accomplish this objective the sand tracer method was used for the study. Visual observations and instrument recordings of the environment factors were also made during the tracing operations. The investigation covered a time span from September 14, 1976 to March 12, 1977. (PDF contains 68 pages.)
Resumo:
Many Central Florida lakes, particularly those in the Kissimmee River watershed, are maintained 0.5 to 1.0 m lower than historic (pre-1960) levels during the summer hurricane season for flood control purposes. These lower water levels have allowed proliferation and formation of dense monotypic populations of pickerelweed ( Pontederia cordata L.) and other broadleaf species that out compete more desirable native grasses (Hulon, pers. comm., 2002). Due to the limited availability of data on the effects of metsulfuron methyl on wetland plants, particularly in Florida, the present study was carried out with the objective of testing its phytotoxicity on six wetland species, to determine the feasibility of its use for primary pickerelweed control.
Resumo:
In addition to describing the species of tunicates found areound Monterey Bay California, it provides a taxonomic key. This is a student paper done for a University of California Berkeley Zoology class. Since UCB didn't have its own marine lab at the time, it rented space at Hopkins Marine Station where this work was done. Donald Putnam Abbott went on to earn his Ph.D. from Berkeley and later became a Stanford professor at Hopkins Marine Station. (PDF contains 35 pages)
Resumo:
Samples of zooplankton and fish were collected from six sampling points in Nyanza Gulf, Lake Victoria in Kenya from June to December 1998, using 76 mu m memo-filament mesh size strainer and an 80 mu m mesh size plankton net. Identification and enumeration were done in the laboratory. Occurrence, numerical and points methods were used in stomach anlaysis of fish. Copepoda, Rotifera and Cladocera were the major zooplankton groups identified, zooplankton such as Moina, Daphnia and Caridina nilotica were important prey items for Lates niloticus, Oreochromis niloticus and Rastrineobola argentea
Resumo:
An extreme dry-down and muck-removal project was conducted at Lake Tohopekaliga, Florida, in 2003-2004, to remove dense vegetation from inshore areas and improve habitat degraded by stabilized water levels. Vegetation was monitored from June 2002 to December 2003, to describe the pre-existing communities in terms of composition and distribution along the environmental gradients. Three study areas (Treatment-Selection Sites) were designed to test the efficacy of different treatments in enhancing inshore habitat, and five other study areas (Whole-Lake Monitoring Sites) were designed to monitor the responses of the emergent littoral vegetation as a whole. Five general community types were identified within the study areas by recording aboveground biomasses and stem densities of each species. These communities were distributed along water and soils gradients, with water depth and bulk density explaining most of the variation. The shallowest depths were dominated by a combination of Eleocharis spp., Luziola fluitans, and Panicum repens; while the deeper areas had communities of Nymphaea odorata and Nuphar luteum; Typha spp.; or Paspalidium geminatum and Hydrilla verticillata. Mineralized soils were common in both the shallow and deep-water communities, while the intermediate depths had high percentages of organic material in the soil. These intermediate depths (occurring just above and just below low pool stage) were dominated by Pontederia cordata, the main species targeted by the habitat enhancement project. This emergent community occurred in nearly monocultural bands around the lake (from roughly 60–120 cm in depth at high pool stage) often having more diverse floating mats along the deep-water edge. The organic barrier these mats create is believed to impede access of sport fish to shallow-water spawning areas, while the overall low diversity of the community is evidence of its competitive nature in stabilized waters. With continued monitoring of these study areas long-term effects of the restoration project can be assessed and predictive models may be created to determine the efficacy and legitimacy of such projects in the future.
Resumo:
The zooplankton community of the littoral zone of Nyanza Gulf, Lake Victoria, was studied between June 1998 and June 1999 to identify and quantify various zooplankton groups, and investigate the interactions that occur between them and the littoral fish through the food chain. Zooplankton samples were collected from five stations using a 83 micro-m mesh size plankton net hauled vertically through the water column. Fish samples were obtained by beach seine, except at Gingra (May 1999), where trawl samples were used. Gut/stomach analysis was carried out on the three major commercial species, Lates niloticus (L.), Oreochromis niloticus (L.) and Rastrineobola argentea (Pellegrin).
Resumo:
The present bibliography collects references on lagoon and coastal environments in Côte d'Ivoire. It is mainly based on: - the draft bibliography prepared by Charles-Dominique and Durand in 1979, edited in the Archives Scientifiques du Centre de Recherches Océanographiques d'Abidjan (vol. 5 no. 2); - the synthesis on the marine environment, published in 1993 (LeLoeuff, Marchal and Amon-Kothias editors); - and the synthesis on the lagoon environment, published in 1994 (Durand, Dufour, Guiral and Zabi editors). In spite of a careful check of the available documents, it is more than possible that references are lacking or erroneous. That's why this bibliography is still a draft, and the author will be glad to receive complements and/or corrections from lectors. After these contributions, a more comprehensive version will be proposed. Remarks can be sent to this e-mail: arfi@ortsom.orstom.fr or to the postal address.
Resumo:
This paper presents a large scale (1/10000) bathymetric chart along with the beach (s.l.) and shoreface schemes of Port-Bouet littoral. All these charts and maps contributed to identify the three morphological sub-areas which characterize the whole littoral area of Port-Bouet.
Resumo:
The introduction is followed by a resume of the biogeographic factors and the principal work. The characteristics of zooplankton in different regions are presented based on regular research in Santa Helena Bay and Walvis Bay and the research carried out by William Scoresby. Certain factors of the digestive system of South African plankton are discussed. The next section concerns research in intertropical and equatorial regions in the Gulf of Guinea. It considers the littoral region of Angola, the Pointe Noire region and discusses the density and complexity of stocks. The last section concerns the zooplankton of Nigeria, Ghana and the Ivory Coast and discusses the grouping of species and compares the results.
Resumo:
Situated as it is on the north-western section of the Indian Ocean, the Cochin littoral has played a very significant role in the history of India. Despite being an extremely interesting region from the point of view of oceanographic studies, the Indian Ocean in general has been one of the least scientifically known regions of our planet.
Resumo:
The Nha Trang Bay (latitude 12°15'N) and central areas of Vietnam present strong ecological differences from other parts of the country.
Resumo:
On the area in relation with the very wave battered made, the associations to be noted are: 1) association with Bangia sp., which is seasonal and located at the level of Brachytrichia maculans. 2) Association with Chthamalus stellatus, which is very well developed over under the oysters’ level. 3) Association with Dermonema frappieri, which form a narrow band over the Chnoospora minima band. At the same level are located the associations with Ectocarpus braeviarticulatus, with Centroceras clavulatum, with Gymnogongrus Sereneii and with Chaetomorpha antennina. The infralittoral level does not present any conspicuous different.
Resumo:
In the "Flore Générale de l'Indochine" three species of phanerogams have been described: Halophila ovalis (R. Br.) Hook. f., Diplanthera uninervis (Forsk.) Aschers. and Ruppia rostella Koch in Rchb. In 1954, Dawson added to this list Halophila Beccari Aschers. and Thalassia hemprichii (Ehrenb.) Aschers. Even Mr. Feldmann found in the herbarium of the Oceanographic Institute of Nha-Trang, the Cymodocea rotundata (Ehrenb. & Hernpr.) Asch. & Schweinf., that the authors found in Cua-Be (Nha trang), Qui-Nhon and Da-Nang (Tourane).
Resumo:
In this part 1, after a brief description of the habitat, the author describes in details (in descending order) the supralittoral, littoral and infralittoral zones. The author describes many permanent groups of Cyanophyceae in the higher horizon of intertidal zone, the cosmopolitan group of Navicula Grevillei, Hildenbrandtia prototypus, the pantropical group of Calothrix pilosa, Chaetomorpha antennina, indopacific group of Dermonema Frappieri, Sargassum, Padina, Thatassia Hemprichii, Halophila. The group of cold or temperate habitat with Bangiophycideae are present in winter. Some are described, formed by the oysters, Vermetus or Cirripeds, or by the algae (Calothrix, Brachytrichia, Gelidium, Dermonema, Chaetomorpha).
Resumo:
So far, the assessment of Vietnamese coastal bios has not been thoroughly researched yet. Only two short notes of P. H. Fischer in 1952 on the coast of Indochina and Cap Saint-Jacques (Vungtau) can be cited. This paper gives a summary of work carried out since 1956. The study was conducted using measurements and sketches made on site and after photos.