Consulta: subjectFacets:"Seagrass"
Registros recuperados: 45
Data/hora: 05/06/2024 19:11:33

Seagrass ecosystems
Provedor de dados: 13
Autores: Phillips, R. C.; Milchakova, N. A.
The seagrass ecosystem is defined as a unit of biological organization comprised of interacting biotic and abiotic components. The structural components are shelter and food and feeding pathways and biodiversity. Functional components include the rate of nutrient cycling, the rate of energy flow, and biological regulation. Healthy intact seagrass ecosystems provide services since they relate to the health, stability and well-being of the environment in which they live, but also to that of human populations.
Tipo: Journal Contribution
Palavras-chave: Seagrass; Ecosystem; Production; Nutrient cycling; Energy flow; Biological regulation; Ecosystem services; Морские травы; Экосистема; Поток энергии; Биологическая регуляция; Экосистемные услуги Ecosystems Energy flow Ecosystems Energy flow http://aims.fao.org/aos/agrovoc/c_2482 http://aims.fao.org/aos/agrovoc/c_2569.
Ano: 2003
URL: http://repository.ibss.org.ua/dspace/handle/99011/42

Seasonal variation of the crustacean fauna in the belowground and aboveground strata in a Halodule wrightii meadow of northeastern Brazil
Provedor de dados: 76
Autores: Barros,Kcrishna V. S.; Souza-Filho,Jesser F.; Paiva,Ricardo J. C.; Araújo-Silva,Catarina L.; Almeida,Alexandre O.; Rocha-Barreira,Cristina A.
ABSTRACT The different microhabitats provided by seagrasses and the habit of the species determinate the vertical distribution of crustaceans. This study verified the influence of the seasonality on the spatial distribution of the crustacean community associated with a Halodule wrightii meadow. From April 2006 to July 2007, we performed fifteen samplings in Goiabeiras Beach, Ceará State, each with five sectioned replicates in belowground and aboveground. Cumaceans and the amphipod Hyale media (Dana, 1853) had a higher frequency, density, and dominance than the other taxa, in both strata. The community exhibited gradual changes along the study, in both the belowground and aboveground strata, but the seagrass structure was not sufficient to explain the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Seagrass; Shoal grass; Benthic communities.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212017000100248

Population ecology and shell chemistry of a phytal ostracode species (Loxoconcha matagordensis) in the Chesapeake Bay watershed
Provedor de dados: 5
Autores: Vann, Cd; Cronin, Tm; Dwyer, Gs.
Population ecology and shell chemistry were studied in the phytal ostracode Loxoconcha matagordensis (Swain 1955) collected from Zostera marina seagrass beds in the Chesapeake Bay to provide seasonal constraints on shell secretion time for paleothermometry. Population density and age structure were defined by two main breeding cycles that occurred between 01 to 15 June and 02 to 16 August 2001. The time interval between breeding cycles was similar to2 months and total juvenile standing crop increased almost three-fold between the first and second breeding cycles. Dark brown over-wintered adults comprised the majority of the population between March and April 2001, while newly secreted translucent adults were predominant between June and September. Seasonal...
Tipo: Text
Palavras-chave: Ostracoda; Paleoclimatology; Ecology; Minor elements; Holocene; Seagrass.
Ano: 2004
URL: https://archimer.ifremer.fr/doc/00229/33995/32356.pdf

Global trends in air-water CO2 exchange over seagrass meadows revealed by atmospheric Eddy Covariance
Provedor de dados: 5
Autores: Van Dam, Bryce; Polsenaere, Pierre; Barreras-apodaca, Aylin; Lopes, Christian; Sanchez-mejia, Zulia; Tokoro, Tatsuki; Kuwae, Tomohiro; Guttierrez Loza, Lucia; Rutgersson, Anna; Fourqueren, James; Thomas, Helmut.
Coastal vegetated habitats like seagrass meadows can mitigate anthropogenic carbon emissions by sequestering CO2 as “blue carbon” (BC). Already, some coastal ecosystems are actively managed to enhance BC storage, with associated BC stocks included in national greenhouse gas inventories. However, the extent to which BC burial fluxes are enhanced or counteracted by other carbon fluxes, especially air‐water CO2 flux (FCO2) remains poorly understood. In this study, we synthesized all available direct FCO2 measurements over seagrass meadows made using atmospheric Eddy Covariance, across a globally‐representative range of ecotypes. Of the four sites with seasonal data coverage, two were net CO2 sources, with average FCO2 equivalent to 44 ‐ 115% of the global...
Tipo: Text
Palavras-chave: Seagrass; Blue Carbon; CO2 Flux; Eddy Covariance; Carbon Cycle; Air‐sea interaction.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00682/79435/82041.pdf

Assessment of the ecological status of Mediterranean French coastal waters as required by the Water Framework Directive using the Posidonia oceanica Rapid Easy Index: PREI
Provedor de dados: 5
Autores: Gobert, Sylvie; Sartoretto, Stephane; Rico-raimondino, Valerie; Andral, Bruno; Chery, Aurelia; Lejeune, Pierre; Boissery, Pierre.
This paper describes the PREI (Posidonia oceanica Rapid Easy Index), a method used to assess the ecological status of seawater along Mediterranean French coasts. The PREI was drawn up according to the requirements of the Water Framework Directive (WFD 2000/60/EC) and was tested on 24 and 18 stations in PACA (Provence-Alpes-Cotes d'Azur) and Corsica, respectively. The PREI is based on five metrics: shoot density, shoot leaf surface area, E/L ratio (epiphytic biomass/leaf biomass), depth of lower limit, and type of this lower limit. The 42 studied stations were classified in the first four levels of status: high, good, moderate and poor. The PREI values ranged between 0.280 and 0.847; this classification is in accordance with our field knowledge and with our...
Tipo: Text
Palavras-chave: Water Frame Directive; Ecological Quality Ratio; Coastal water; Mediterranean Sea; Posidonia oceanica; Seagrass.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6949.pdf

Long-term evolution (1988-2008) of Zostera spp. meadows in Arcachon Bay (Bay of Biscay)
Provedor de dados: 5
Autores: Plus, Martin; Dalloyau, Sebastien; Trut, Gilles; Isabelle, Auby; De Montaudouin, Xavier; Emery, Eric; Claire, Noel; Christophe, Viala.
The spatial variability of seagrass meadows in Arcachon Bay, was studied between 1988 and 2008 using a combination of mapping techniques based on aerial photographs for intertidal dwarf-grass (Zostera noltti) beds and acoustic sonar for permanently submerged eelgrass (Zostera marina) populations. The results show a severe decline over the period for both species, as well as an acceleration of the decline since 2005 for Z. noltii. The total surface regression over the studied period is estimated to be 22.8 km(2) for Z. noltii and 2.7 km(2) for Z. marina, which represent declines of 33 and 74% respectively. Environmental data time series spanning the same period were investigated in order to seek the causes for such a decline. The calculated inter-annual...
Tipo: Text
Palavras-chave: Seagrass; Temporal evolution; Aerial photography; Acoustic sonar; Zostera noltii; Zostera marina; Arcachon Bay.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00003/11376/7969.pdf

Comparative Analysis of Stability-Genetic Diversity in Seagrass (Posidonia oceanica) Meadows Yields Unexpected Results
Provedor de dados: 5
Autores: Arnaud-haond, Sophie; Marba, Nuria; Diaz-almela, Elena; Serrao, Ester A.; Duarte, Carlos M.
The diversity-stability relationship is the subject of a long-standing debate in ecology, but the genetic component of diversity has seldom been explored. In this study, we analyzed the interplay between genetic diversity and demographic responses to environmental pressures. This analysis included 30 meadows formed by the Mediterranean endemic seagrass, Posidonia oceanica, showing a wide range of population dynamics ranging from a near equilibrium state to steep decline due to strong environmental pressures close to aquaculture installations. Our results show that sedimentation rates are much better predictors of mortality than clonal or genetic components. An unexpected positive trend was observed between genotypic diversity and mortality, along with a...
Tipo: Text
Palavras-chave: Seagrass; Demography; Clonality; Genetic richness; Diversity-stability; Posidonia oceanica.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00006/11693/8498.pdf

Disentangling the Influence of Mutation and Migration in Clonal Seagrasses Using the Genetic Diversity Spectrum for Microsatellites
Provedor de dados: 5
Autores: Arnaud-haond, Sophie; Moalic, Yann; Hernandez-garcia, Emilio; Eguiluz, Victor M.; Alberto, Filipe; Serrao, Ester A.; Duarte, Carlos M.
The recurrent lack of isolation by distance reported at regional scale in seagrass species was recently suggested to stem from stochastic events of large-scale dispersal. We explored the usefulness of phylogenetic information contained in microsatellite loci to test this hypothesis by using the Genetic Diversity Spectrum (GDS) on databases containing, respectively, 7 and 9 microsatellites genotypes for 1541 sampling units of Posidonia oceanica and 1647 of Cymodocea nodosa. The simultaneous increase of microsatellite and geographic distances that emerges reveals a coherent pattern of isolation by distance in contrast to the chaotic pattern previously described using allele frequencies, in particular, for the long-lived P. oceanica. These results suggest...
Tipo: Text
Palavras-chave: Clonality; Genetic Diversity Spectrum; Genetic divergence; Microsatellites; Seagrass; Stepwise mutation.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00182/29292/27733.pdf

Preliminary data on the impact of fish farming facilities on Posidonia oceanica meadows in the Mediterranean
Provedor de dados: 5
Autores: Pergent, G; Mendez, S; Pergent-martini, C; Pasqualini, V.
While the extension of aquaculture along the coasts of the Mediterranean islands is today an economic priority, no data is available on the impact of these facilities on the littoral environment in general, and in particular on the Posidonia oceanica meadows that are responsible for the richness and diversity of these biotopes. The impact of fish farming facilities in the marine littoral environment is assessed at three Mediterranean sites in Corsica and Sardinia. Various parameters are considered: (i) the amount of light available, (ii) the nature of the sediment, and (iii) the vitality of the Posidonia oceanica beds. The findings confirm the impact of the aquaculture facilities within the water column (increase in turbidity, enrichment of the sediment in...
Tipo: Text
Palavras-chave: Aquaculture; Environnement; Phanérogames marines; Posidonia oceanica; Méditerranée; Aquaculture; Environment; Seagrass; Posidonia oceanica; Mediterranean.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00325/43631/43251.pdf

Cartographie des biocénoses marines de Guadeloupe à partir de données SPOT (récifs coralliens, phanérogames marines, mangroves)
Provedor de dados: 5
Autores: Chauvaud, S; Bouchon, C; Maniere, R.
In the framework of a comprehensive study of the coastal marine ecosystems of Guadeloupe Island (French West Indies), a remote sensing survey of marine communities was conducted in the Bay of the Grand Cul-de-Sac Marin. Pictures of SPOT satellite were used. At first sight, XS data from SPOT did not seem to be well adapted to extract information from deepest underwater areas. In the present study, a method for analysis of XS data was developed, which increases tenuous spectral differences associated to very low intensity signals. This technique led to a better distinction of objects, even the deepest ones. Reference surfaces were then identified in the field and a reliable supervised classification was conducted, which reflected the high diversity of...
Tipo: Text
Palavras-chave: Télédétection; Cartographie; Récif corallien; Phanérogame marine; Mangrove; Remote sensing; Mapping; Coral reef; Seagrass; Mangrove.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/00291/40267/38646.pdf

Effects of fish farming on seagrass (Posidonia oceanica) in a Mediterranean bay: seagrass decline after organic loading cessation
Provedor de dados: 5
Autores: Delgado, O; Ruiz, J; Perez, M; Romero, J; Ballesteros, E.
The effects of fish farming on a seagrass (Posidonia oceanica) meadow at Fornells Bay, Minorca (Balearic Islands) were studied. Changes in plant and meadow features (e.g. shoot morphology, shoot density, biomass, rhizome growth, nutrient and soluble sugars concentrations...) in three stations along a transect from a disturbed (organic pollution due to fish cultures) to an undisturbed site were assessed. The fish culture had ceased in 1991; however, seagrass decline, already reported in a previous study for the period 1988-1990, was still taking place at the time of sampling (July 1994). Differences between stations were very clear; the station closest to the fish cages showed reduced shoot density, shoot size, underground biomass, sucrose concentration and...
Tipo: Text
Palavras-chave: Aquaculture; Phanérogame marine; Posidonia oceanica; Eutrophisation; Caractéristique du sédiment; Aquaculture; Seagrass; Posidonia oceanica; Eutrophication; Sediment characteristics.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00325/43632/43250.pdf

Mapping of Posidonia oceanica beds around Elba Island (western Mediterranean) with integration of direct and indirect methods
Provedor de dados: 5
Autores: Piazzi, L; Acunto, S; Cinelli, F.
Direct and indirect methods were used for mapping Posidonia oceanica beds around Elba Island. Side scan sonar and a visual infra red scanner were used to detect the extension of beds. Also, direct observations were adopted to assess the bed density and to calibrate the indirect methods. Samples of P. oceanica were collected and phenological variables and macroalgal epiphytes were studied to assess the health of the beds. P. oceanica around Elba Island covered an area of 3 680 ha. The largest beds occupied the four main gulfs of the island, characterized by gentle slopes and sandy bottoms. There, the beds showed uniform cover while a patchy structure was common on the rocky and steep bottoms of the western and south-eastern coasts of the island. P. oceanica...
Tipo: Text
Palavras-chave: Posidonia oceanica; Algues; Cartographie; Sonar latéral; Télédétection aérienne; Méditerranée; Posidonia oceanica; Seagrass; Algae; Mapping; Airborne teledetection; Mediterranean.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00324/43567/44064.pdf

Evaluation of large-scale unsupervised classification of New Caledonia reef ecosystems using Landsat 7 ETM+ imagery
Provedor de dados: 5
Autores: Bouvet, G; Ferraris, J; Andrefouet, S.
The capacity of the Landsat 7 Enhanced Thematic Mapper Plus sensor to classify the shallow benthic ecosytems of New Caledonia (South Pacific) is tested using a novel unsupervised classification method. The classes are defined by using a set of multiple spectral decision rules based on the image spectral bands. A general model is applied to the entire Southwest lagoon (5500 km(2)) and tested on three representative sites: a section of the barrier reef, a cay reef flat rich in corals, and a cay reef flat rich in algae and seagrass beds. In the latter one, the classification results are compared with a locally optimized model, with aerial color photographs and extensive ground-truthed observations. Results show that a reconnaissance of the main benthic...
Tipo: Text
Palavras-chave: Télédétection; Modèle statistique; Indo-Pacifique; Herbier; Corail; Remote sensing; Statistical modeling; Indo-Pacific; Seagrass; Coral.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/00322/43273/43004.pdf

Application of the coastal ecosystem complex concept toward integrated management for sustainable coastal fisheries under oligotrophication
Provedor de dados: 5
Autores: Hori, Masakazu; Hamaoka, Hideki; Hirota, Masahito; Lagarde, Franck; Vaz, Sandrine; Hamaguchi, Masami; Hori, Juri; Makino, Mitsutaku.
Harmonizing coastal fisheries with water-quality improvement has become an essential factor for the sustainable use of coastal ecosystem services. Here, we present the scope of our study based on an interdisciplinary approach including ecological actions, socio-economic actions and socio-psychological actions. We chose to focus on the interaction between oyster aquaculture and seagrass vegetation as a typical ecological action using the coastal ecosystem complex (CEC) concept. Coastal organisms have adapted their traits to the environment over a long period of time, so that restoration of the CEC represents reconstruction of the original process of coastal production. Subtidal seagrass vegetation with intertidal oyster reefs is the original CEC in Japan,...
Tipo: Text
Palavras-chave: Oyster aquaculture; Seagrass; Indigenous and local knowledge; Integrated coastal management.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00429/54019/57439.pdf

Organic and inorganic human-induced contamination of Posidonia oceanica meadows
Provedor de dados: 5
Autores: Pergent, Gerard; Labbe, Celine; Lafabrie, Celine; Kantin, Roger; Pergent-martini, Christine.
In coastal environments, plants are used for phytoremediation of contamination. Organic and inorganic contaminants may be due to natural and/or anthropogenic sources. The aim of this study is to compare inorganic (trace metal) and organic (PAH) contamination in Posidonia oceanica and to analyse the relationship between these types of pollutants indeed very few studies have been interested in their correlations and common sources. P. oceanica leaves were collected in two sites exhibiting different levels of human-induced pressure. Higher values were recorded in the more polluted site (Toulon) for trace metals (Ag, Hg, Pb) as well as for PAHs (Medium Molecular Weight and High Molecular Weight) due to the presence of the city and/or harbour in proximity. For...
Tipo: Text
Palavras-chave: Trace metals; Polycyclic aromatic hydrocarbons; Contamination; Seagrass; Posidonia oceanica; Mediterranean.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00038/14913/15671.pdf

Latitude, temperature, and habitat complexity predict predation pressure in eelgrass beds across the Northern Hemisphere
Provedor de dados: 5
Autores: Reynolds, Pamela L.; Stachowicz, John J.; Hovel, Kevin; Bostrom, Christoffer; Boyer, Katharyn; Cusson, Mathieu; Eklof, Johan S.; Engel, Friederike G.; Engelen, Aschwin H.; Eriksson, Britas Klemens; Fodrie, F. Joel; Griffin, John N.; Hereu, Clara M.; Hori, Masakazu; Hanley, Torrance C.; Ivanov, Mikhail; Jorgensen, Pablo; Kruschel, Claudia; Lee, Kun-seop; Mcglathery, Karen; Moksnes, Per-olav; Nakaoka, Masahiro; O'Connor, Mary I.; O'Connor, Nessa E.; Orth, Robert J.; Rossi, Francesca; Ruesink, Jennifer; Sotka, Erik E.; Thormar, Jonas; Tomas, Fiona; Unsworth, Richard K. F.; Whalen, Matthew A.; Duffy, J. Emmett.
Latitudinal gradients in species interactions are widely cited as potential causes or consequences of global patterns of biodiversity. However, mechanistic studies documenting changes in interactions across broad geographic ranges are limited. We surveyed predation intensity on common prey (live amphipods and gastropods) in communities of eelgrass (Zostera marina) at 48 sites across its Northern Hemisphere range, encompassing over 37 degrees of latitude and four continental coastlines. Predation on amphipods declined with latitude on all coasts but declined more strongly along western ocean margins where temperature gradients are steeper. Whereas insitu water temperature at the time of the experiments was uncorrelated with predation, mean annual...
Tipo: Text
Palavras-chave: Biogeography; Latitude; Mesograzer; Predation; Seagrass; Species interactions; Temperature; Zostera.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00610/72246/71053.pdf

Blue Carbon Storage Capacity of Temperate Eelgrass (Zostera marina) Meadows
Provedor de dados: 5
Autores: Rohr, Maria Emilia; Holmer, Marianne; Baum, Julia K.; Bjork, Mats; Chin, Diana; Chalifour, Lia; Cimon, Stephanie; Cusson, Mathieu; Dahl, Martin; Deyanova, Diana; Duffy, J. Emmet; Eklof, Johan S.; Geyer, Julie K.; Griffin, John N.; Gullstrom, Martin; Hereu, Clara M.; Hori, Masakazu; Hovel, Kevin A.; Hughes, A. Randall; Jorgensen, Pablo; Kiriakopolos, Stephanie; Moksnes, Per-olav; Nakaoka, Masahiro; O'Connor, Mary I.; Peterson, Bradley; Reiss, Katrin; Reynolds, Pamela L.; Rossi, Francesca; Ruesink, Jennifer; Santos, Rui; Stachowicz, John J.; Tomas, Fiona; Lee, Kun-seop; Unsworth, Richard K. F.; Bostrom, Christoffer.
Despite the importance of coastal ecosystems for the global carbon budgets, knowledge of their carbon storage capacity and the factors driving variability in storage capacity is still limited. Here we provide an estimate on the magnitude and variability of carbon stocks within a widely distributed marine foundation species throughout its distribution area in temperate Northern Hemisphere. We sampled 54 eelgrass (Zostera marina) meadows, spread across eight ocean margins and 36 degrees of latitude, to determine abiotic and biotic factors influencing organic carbon (C-org) stocks in Zostera marina sediments. The C-org stocks (integrated over 25-cm depth) showed a large variability and ranged from 318 to 26,523gC/m(2) with an average of 2,721gC/m(2). The...
Tipo: Text
Palavras-chave: Blue carbon; Seagrass; Z; Marina.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00610/72199/70994.pdf

Variations à différentes échelles spatiales de l'herbier à Posidonia oceanica (L.) Delile ; effets sur les paramètres physico-chimiques du sédiment
Provedor de dados: 5
Autores: Gobert, S; Kyramarios, M; Lepoint, G; Pergent-martini, C; Bouquegneau, Jm.
The biometric parameters (shoot density, length and width of leaves, leaf and epiphyte biomasses, leaf surface) of the P. oceanica meadow present a significant spatial variability at the mesoscale level (100m(2)). All the parameters studied, excepting the number of leaves, decrease according to the depth. The horizontal spatial variations (centrifuge and centripetal distributions) reach a maximum in the shallower areas. The analysis of the microstructures (m(2)) of the meadow has not allowed a relationship to be established between the spatial variations of the biometric parameters and the environmental factors in the sediment (pH, water and organic matter content, red-ox potential, nutrient content). The heterogeneity of the meadow in the Revellata Bay...
Tipo: Text
Palavras-chave: Posidonia oceanica; Distribution spatiale; Biomasse; Sédiment; Phanérogame; Méditerranée; Posidonia oceanica; Spatial distribution; Biomass; Sediment; Seagrass; Mediterranean Sea.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/00322/43277/43009.pdf

Carbon sequestration loss following Zostera noltei decline in the Arcachon Bay (France)
Provedor de dados: 5
Autores: Ribaudo, Cristina; Plus, Martin; Ganthy, Florian; Auby, Isabelle.
The worldwide decline of seagrass meadows may result in the loss of relevant ecosystem services such as the carbon sequestration within marine ecosystems. In this paper, net primary production (NPP) of Zostera noltei meadows was assessed in the Arcachon Bay (SW France) with the aim of understanding the impact of meadows decline on C sequestration capacity at a basin scale. Net growth rates obtained by means of a year-long leaf-marking experiment (2005-2006) were coupled to interannual biomass measurements (1983-2010) to obtain a direct estimate of NPP. Concurrently, an indirect estimate was obtained through a mathematical model which embedded natural factors variation (temperature, light and nutrients). Z. noltei seasonal growth and leaf morphometry...
Tipo: Text
Palavras-chave: Seagrass; Meadow regression; Macrotidal lagoon; Growth model; Nutrient leaf resorption.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00309/42061/41357.pdf

Benthic metabolism in shallow coastal ecosystems of the Banc d'Arguin, Mauritania
Provedor de dados: 5
Autores: Clavier, Jacques; Chauvaud, Laurent; Amice, Erwan; Lazure, Pascal; Van Der Geest, Matthijs; Labrosse, Pierre; Diagne, Ahmed; Carlier, Antoine; Chauvaud, Sylvain.
Benthic primary production and respiration were investigated at 4 sites representative of the major coastal communities bordering the Sahara Desert in the Banc d'Arguin, Mauritania, Western Africa. These sites correspond to intertidal Zostera noltii beds (270 km(2)), intertidal bare sediments (88 km(2)), subtidal Cymodocea nodosa beds (374 km(2)), and subtidal bare sediments (311 km(2)). At each site, production-irradiance relationships were established in situ in November 2008 and January 2010, and used to calculate daily carbon fluxes for these communities. In intertidal areas, compared to emersion, the gross maximal photosynthetic rates for Z. noltii bed and bare sediment communities were on average 8-and 7-fold higher during immersion, respectively;...
Tipo: Text
Palavras-chave: Seagrass; Carbon metabolism; Intertidal; Subtidal; Respiration; Primary; Production; Western Africa.
Ano: 2014
URL: https://archimer.ifremer.fr/doc/00189/29987/28460.pdf

Ecologie trophique de la tortue verte Chelonia mydas dans les herbiers marins et algueraies du sud-ouest de l’océan Indien
Provedor de dados: 5
Autores: Ballorain, Katia.
Reproduction of sea turtles primarily relies on body reserves stored during the time spent on foraging grounds prior to the nesting season. Accordingly, the investigation of foraging behaviour of sea turtles is critical for better assessing their biology but also for conservation issues of these endangered species. Sea turtles contribute significantly to the consuming biomass of their ecosystem and hence to its functioning, thus providing natural indications of the health of the ecosystem. Yet the trophic ecology of sea turtles is poorly documented because their feeding grounds remain poorly known and for most of them hardly accessible. Among sea turtles the green turtle is the only species where sub-adults and adults are mostly herbivorous feeding on...
Tipo: Text
Palavras-chave: Tortue verte Chelonia mydas; Herbier marin; Phanérogame; Algueraie; Mayotte; Réunion; Sud-ouest de l’Océan Indien; Écologie trophique; Green turtles Chelonia mydas; Seagrass; Algae; Mayotte; Reunion Island; Southwestern Indian Ocean; Trophic ecology.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00031/14254/11538.pdf

Scaling of processes shaping the clonal dynamics and genetic mosaic of seagrasses through temporal genetic monitoring
Provedor de dados: 5
Autores: Becheler, Ronan; Benkara, Elsa; Moalic, Yann; Hily, Christian; Arnaud-haond, Sophie.
Theoretically, the dynamics of clonal and genetic diversities of clonal plant populations are strongly influenced by the competition among clones and rate of seedling recruitment, but little empirical assessment has been made of such dynamics through temporal genetic surveys. We aimed to quantify 3 years of evolution in the clonal and genetic composition of Zostera marina meadows, comparing parameters describing clonal architecture and genetic diversity at nine microsatellite markers. Variations in clonal structure revealed a decrease in the evenness of ramet distribution among genets. This illustrates the increasing dominance of some clonal lineages (multilocus lineages, MLLs) in populations. Despite the persistence of these MLLs over time, genetic...
Tipo: Text
Palavras-chave: Clonality; Seagrass; Spatio-temporal genetic structure; Zostera marina.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00181/29254/32174.pdf

Density-dependent growth of bivalves dominating the intertidal zone of Banc d'Arguin, Mauritania: importance of feeding mode, habitat and season
Provedor de dados: 5
Autores: Van Der Geest, Matthijs; Van Der Lely, Jorge A. C.; Van Gils, Jan A.; Piersma, Theunis; Lok, Tamar.
Accurate predictions of population dynamics require an understanding of the ways by which environmental conditions and species-specific traits affect the magnitude of density dependence. Here, we evaluated the potential impact of season and habitat (characterized by sediment grain size and seagrass biomass) on the magnitude of density dependence in shell growth of 3 infaunal bivalve species dominating the tropical intertidal benthic communities of Banc d'Arguin, Mauritania. Two of our focal species were filter feeders (Senilia senilis and Pelecyora isocardia) and one was a facultative mixotroph (Loripes orbiculatus), mainly relying on organic carbon provided by sulphide-oxidizing endosymbiotic gill-bacteria (i.e. chemosymbiotic). Distinguishing 2 seasons,...
Tipo: Text
Palavras-chave: Carrying capacity; Chemosymbiosis; Density dependence; Environmental heterogeneity; Feeding guild; Seagrass; Soft-sediment habitat.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00492/60319/63745.pdf

Étude et modélisation des populations de macrophytes dans la lagune de Thau (Hérault, France)
Provedor de dados: 5
Autores: Plus, Martin.
The works carried out can be divided in three main lines : design and management of experimental studies on primary production processes, macrophyte spatial distribution study and development of macrophyte and seagrass numerical models.  In situ and in vitro experiments have been performed with the aim of studying the processes and the parameters involved in the photosynthesis-respiration system, as well as to establish the main biotic (self-shading effect, physiology of the photosynthesis, carbon, nitrogen and chlorophyll tissu contents) and abiotic (temperature, light and nutrients) factors controlling macrobenthic primary production. A seagrass ecosystem model based on nitrogen and oxygen fluxes has been developped. Model calibration and validation have...
Tipo: Text
Palavras-chave: Primary production; Light; Nitrogen; Nutrients; Mathematical model; Thau lagoon; Seagrass; Macrophytes; Production primaire; Lumière; Azote; Nutriments; Model mathématique; Thau; Phanérogames; Macrophytes.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/these-6518.pdf

Microsatellite markers developed through pyrosequencing allow clonal discrimination in the invasive alga Caulerpa taxifolia
Provedor de dados: 5
Autores: Arnaud-haond, Sophie; Candeias, Rui; Serrao, Ester A.; Teixeira, Sara.
Polymorphic microsatellites were developed for the invasive green algae Caulerpa taxifolia using next generation DNA sequencing. Results showed a limited rate of microsatellites for the amount of sequences, possibly explaining failure of previous attempts for microsatellite development through classical methods. Eight polymorphic loci were selected that exhibited polymorphism and a null or negligible rate of amplification failure. The number of alleles per locus ranged from two to seven. The reconstruction of Multi Locus Genotypes and the heterozygosity and departure from Hardy-Weinberg equilibrium confirmed the influence of clonal reproduction and showed the usefulness of this set of markers to successfully discriminate clonal lineages and analyze the...
Tipo: Text
Palavras-chave: Caulerpa taxifolia; Algae; Invasion; Mediterranean; Queensland; New South Wales; Seagrass.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00126/23720/21598.pdf

Spatio-temporal dynamics of a Zostera noltii dominated community over a period of fluctuating salinity in a shallow lagoon, Southern France
Provedor de dados: 5
Autores: Charpentier, Aude; Grillas, P; Lescuyer, F; Coulet, E; Auby, Isabelle.
The consequences of a sudden decrease in water salinity on a macrophyte community dominated by the marine species Zostera noltii were investigated in a shallow coastal lagoon (Southern France). The expected change in the community assemblage was a competitive displacement of Z. noltii by Potamogeton pectinatus and Ruppia cirrhosa. However, the results of an eight-year survey did not validate this hypothesis. Zostera noltii remained dominant after three years at low salinity (ca. 5) and then suddenly disappeared within one year. The decline of Z. noltii was not associated with an increase of other species. The maximum depth colonized by all species decreased, suggesting that light availability became a limiting factor for the aquatic vegetation. The high...
Tipo: Text
Palavras-chave: Mediterranean sea; Lagoon; Recovery; Loss; Turbidity; Salinity; Mapping; Seagrass.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-3693.pdf

Seagrass ecosystem contributions to people's quality of life in the Pacific Island Countries and Territories
Provedor de dados: 5
Autores: Mckenzie, Len J.; Yoshida, Rudi L.; Aini, John W.; Andréfouet, Serge; Colin, Patrick L.; Cullen-unsworth, Leanne C.; Hughes, Alec T.; Payri, Claude E.; Rota, Manibua; Shaw, Christina; Tsuda, Roy T.; Vuki, Veikila C.; Unsworth, Richard K.f.
Seagrass ecosystems provide critical contributions (goods and perceived benefits or detriments) for the livelihoods and wellbeing of Pacific Islander peoples. Through in-depth examination of the contributions provided by seagrass ecosystems across the Pacific Island Countries and Territories (PICTs), we find a greater quantity in the Near Oceania (New Guinea, the Bismarck Archipelago and the Solomon Islands) and western Micronesian (Palau and Northern Marianas) regions; indicating a stronger coupling between human society and seagrass ecosystems. We also find many non-material contributions historically have been overlooked and under-appreciated by decision-makers. Closer cultural connections likely motivate guardianship of seagrass ecosystems by Pacific...
Tipo: Text
Palavras-chave: Seagrass; Ecosystem services; Nature's contributions to people; Traditional ecological knowledge; Coastal zone management; Marine policy.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00689/80150/83218.pdf

Spatial distribution and nutritional requirements of the endosymbiont-bearing bivalve Loripes lacteus (sensu Poli, 1791) in a Mediterranean Nanozostera noltii (Hornemann) meadow
Provedor de dados: 5
Autores: Rossi, Francesca; Colao, Elodie; Jose Martinez, Maria; Klein, Judith C.; Carcaillet, Frederique; Callier, Myriam; De Wit, Rutger; Caro, Audrey.
Sulphur-oxidising endosymbiont-bearing bivalves often inhabit seagrass meadows, where they can control sulphide levels and variably contribute to carbon cycling, by feeding on endosymbiotic bacteria and/or on particulate organic matter from the water column. The patterns of variability in their feeding mode and their spatial distribution within the seagrass meadows are however poorly studied. Seagrass beds form naturally patchy habitats with seagrass-sand edges that may have variable effects on different organisms. The present study aims at understanding differences in feeding mode and abundance of the endosymbiont-bearing bivalve Loripes lacteus (sensu Poli, 1791) as well as the physiological conditions of its endosymbiotic populations between edge and...
Tipo: Text
Palavras-chave: Bivalve; Food web; Mediterranean; Seagrass; Stable isotopes; Symbiosis.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00138/24911/26373.pdf

Etude des intermattes des herbiers à Posidonia oceanica. Analyse à différentes échelles spatiales de la structure des paysages sous-marins
Provedor de dados: 5
Autores: Abadie, Arnaud.
Among Mediterranean marine ecosystems, Posidonia oceanica (L.) Delile seagrass meadows form a habitat playing an important ecological and economical role. They form heterogeneous seascapes influenced by the impact of natural and anthropogenic phenomenon (of which the anchoring of leisure ships). These impacts lead to the formation of sand and bare mat patches called ‘intermattes’. By describing and using intermatte characteristics observed in Calvi Bay and more widely around Corsica, these PhD works precisely described intermatte and P. oceanica seascape dynamics in order to develop new methods of analysis. On the one hand, natural sandy intermattes formed by bottom currents show two types of border. Each has its own characteristics at the level of the...
Tipo: Text
Palavras-chave: Paysage sous-marin; Plante sous-marine; Posidonia oceanica; Intermatte; Ancrage; Gestion; Indices; Seascape; Seagrass; Posidonia oceanica; Patch; Anchoring; Management; Indices.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00659/77075/78396.pdf

Seagrass ecosystems of the Pacific Island Countries and Territories: A global bright spot
Provedor de dados: 5
Autores: Mckenzie, Len J.; Yoshida, Rudi L.; Aini, John W.; Andréfouet, Serge; Colin, Patrick L.; Cullen-unsworth, Leanne C.; Hughes, Alec T.; Payri, Claude E.; Rota, Manibua; Shaw, Christina; Skelton, Posa A.; Tsuda, Roy T.; Vuki, Veikila C.; Unsworth, Richard K.f.
Seagrass ecosystems exist throughout Pacific Island Countries and Territories (PICTs). Despite this area covering nearly 8% of the global ocean, information on seagrass distribution, biogeography, and status remains largely absent from the scientific literature. We confirm 16 seagrass species occur across 17 of the 22 PICTs with the highest number in Melanesia, followed by Micronesia and Polynesia respectively. The greatest diversity of seagrass occurs in Papua New Guinea (13 species), and attenuates eastward across the Pacific to two species in French Polynesia. We conservatively estimate seagrass extent to be 1446.2 km2, with the greatest extent (84%) in Melanesia. We find seagrass condition in 65% of PICTs increasing or displaying no discernible trend...
Tipo: Text
Palavras-chave: Seagrass; Ecosystem services; Habitats; Threats; Resilience; Management; DPSIR.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00689/80148/83210.kml

The Seagrass Methylome Is Associated With Variation in Photosynthetic Performance Among Clonal Shoots
Provedor de dados: 5
Autores: Jueterbock, Alexander; Boström, Christoffer; Coyer, James A.; Olsen, Jeanine L.; Kopp, Martina; Dhanasiri, Anusha K. S.; Smolina, Irina; Arnaud-haond, Sophie; Van De Peer, Yves; Hoarau, Galice.
Evolutionary theory predicts that clonal organisms are more susceptible to extinction than sexually reproducing organisms, due to low genetic variation and slow rates of evolution. In agreement, conservation management considers genetic variation as the ultimate measure of a population’s ability to survive over time. However, clonal plants are among the oldest living organisms on our planet. Here, we test the hypothesis that clonal seagrass meadows display epigenetic variation that complements genetic variation as a source of phenotypic variation. In a clonal meadow of the seagrass Zostera marina, we characterized DNA methylation among 42 shoots. We also sequenced the whole genome of 10 shoots to correlate methylation patterns with photosynthetic...
Tipo: Text
Palavras-chave: DNA methylation; Ecological epigenetics; Clonality; Heat stress; Seagrass; Zostera marina(eelgrass).
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00652/76375/77363.pdf

Entangled effects of allelic and clonal (genotypic) richness in the resistance and resilience of experimental populations of the seagrass Zostera noltii to diatom invasion
Provedor de dados: 5
Autores: Massa, Sonia I.; Paulino, Cristina M.; Serrao, Ester A.; Duarte, Carlos M.; Arnaud-haond, Sophie.
Background: The relationship between species diversity and components of ecosystem stability has been extensively studied, whilst the influence of the genetic component of biodiversity remains poorly understood. Here we manipulated both genotypic and allelic richness of the seagrass Zostera noltii, in order to explore their respective influences on the resistance of the experimental population to stress. Thus far intra-specific diversity was seldom taken into account in management plans, and restoration actions showed very low success. Information is therefore needed to understand the factors affecting resistance and resilience of populations.  Results: Our results show a positive influence of both allelic and genotypic richness on the resistance of...
Tipo: Text
Palavras-chave: Allelic richness; Genotypic richness; Resistance; Resilience; Zostera noltii; Biotic stress; Seagrass.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00166/27748/25946.pdf

Les Caridea (Crustacea: Decapoda) des Herbiers de Phanérogames Marines de Nouvelle-Caledonie (Région de Nouméa) (Systématiquee, écologie, variations Nycthémèrales et vicariance)
Provedor de dados: 16
Autores: Ledoyer, M.
This study deals with Caridean fauna living between the leaves of New-Caledonian seagrassmeadows (Cymodocea sp. principally) from zero to about eight meters and sampled during day and night. Twenty species (all figured) were caught (excluding Alpheidae). All are known. Nevertheless, in some cases, small variations have been observed by comparison with the same species from other areas. Presently, 70 species are recognized from New-Caledonian marine waters, including the 17 species reported in this papier for the first time from that region. Comparison with Caridean fauna of seagrass-meadows of other areas (Australia, Japan, Madagascar) shows a very important resemblance between them.
Tipo: Article / Letter to the editor
Palavras-chave: Crustacea; Caridea; Taxonomy; Ecology; Phanérogames; Marines; Seagrass; Nou- velle-Calédonie; Circadian.; 42.74.
Ano: 1984
URL: http://www.repository.naturalis.nl/record/317743

Spatial and temporal structure of fish assemblages in a hyperhaline coastal system: Ría Lagartos, Mexico
Provedor de dados: 83
Autores: Peralta-Meixueiro,Miguel Angel; Vega-Cendejas,María Eugenia.
The spatial and temporal fish species assemblages were analyzed throughout two annual cycles (2004-2005 and 2007-2008) in the Ría Lagartos Lagoon system, Mexico, via non-parametric multivariate analyses. We compared density and biomass of fish species among five habitat types defined by combinations of structure and environmental characteristics (hyperhaline, rocky, seagrass, channel, and marine), and three climatic seasons (dry, rainy, and northerlies). A total of 11,187 individuals distributed in 32 families and 63 species were collected. The most numerically abundant species were Floridichthys polyommus and Cyprinodon artifrons, while Sphoeroides testudineus contributed to the greatest biomass. Species composition consisted mainly of estuarine and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Euryhaline ichthyofauna; Habitats; Seagrass; Yucatan Peninsula.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000300021

Variación espacio-temporal de grupos morfo-funcionales de macroalgas  en pastos marinos al norte de Ciego de Ávila, Cuba
Provedor de dados: 20
Autores: Avila Alonso, D.; Guimaraes Bermejo, M.; Cárdenas Ortiz, R.
Se determinó la variación espacio-temporal de la biomasa de  los grupos morfo-funcionales de macroalgas y su relación con  las variables ambientales: temperatura, salinidad, oxígeno disuelto y precipitaciones en dos localidades (laguna y playa) de  pastizales al Norte de Ciego de Ávila desde marzo de 2010 a  febrero de 2011. Las colectas se realizaron utilizando marco  cuadrado de 25 cm de lado y se tomaron 15 unidades de muestreo en cada sitio. Se determinaron cinco grupos morfo- funcionales: foliosas y globosas, coriáceas, filamentosas, corticadas y calcáreas articuladas, presentando variaciones espacio- temporales los dos últimos. La laguna tuvo menor diversidad algal (13 géneros) y mayor biomasa total determinado por el  aporte de las calcáreas...
Tipo: Journal Contribution
Palavras-chave: Biomass; Morphometric analysis; Algae; Seagrass; Environmental factors.
Ano: 2013
URL: http://hdl.handle.net/1834/4929

Nutritive and antimicrobial profiles of some seagrasses from bardawil lake, egypt
Provedor de dados: 20
Autores: Daboor, S.M.; Abd El-Hady, H.H.; Ghoniemy, A.E.
Seagrasses species in Bardawil Lake have been defined through broad quantitative sampling. From the biochemical constituent's point of view, two species namely; Cymodocea nodosa and Ruppia cirrhosa were evaluated as feed additives and antimicrobial active compounds. The obtained results showed an obvious increase in chlorophyll "a", carbohydrate and lipid contents in the C. nodosa than R. cirrhosa while protein contents was higher in R. cirrhosa than in C. nodosa. Whole plant tissues powder substance (10.0%w/v) and ethanolic extracts (200μg/ml) of C. nodosa and R. cirrhosa were evaluated against some microorganisms using pour plate technique. Powdered substance of C. nodosa was exhibited the highest antifungal activity than that of R. cirrhosa, also its...
Tipo: Journal Contribution
Palavras-chave: Field Study; Pathogenic bacteria; Seagrass; Pathogenic bacteria; Http://aims.fao.org/aos/agrovoc/c_34317.
Ano: 2007
URL: http://hdl.handle.net/1834/2202

Seagrass Bed Ecosystem Service Valuation: A Case Research on Hepu Seagrass Bed in Guangxi Province
Provedor de dados: 20
Autores: Han, Qiuying; Huang, Xiaoping; Shi, Ping; Zhang, Jingping.
Seagrass bed ecosystem is a coastal ecosystem with abundant biodiversity and high production. It is also an important system for the sustainable development of human society and economy. Based on the local research, statistical data and prevenient research results, the main services of Hepu seagrass ecosystem were analyzed in the paper, including fishing production, nutrient cycling, scientific research, protecting the coast from eroding, climate regulation, biodiversity, culture, bequest valuation, option valuation and existence valuation and so on. At the same time, we used ecological and economic methods for economic evaluation of seagrass in Hepu of Guangxi, including the market valuation method, contingent valuation method, carbon and tax method,...
Tipo: Journal Contribution
Palavras-chave: Seagrass; Ecosystem management.
Ano: 2008
URL: http://hdl.handle.net/1834/5874

Marine Plants of Tanzania. A field guide to the seaweeds and seagrasses of Tanzania.
Provedor de dados: 20
Autores: Oliveira, E.C.; Österlund, K.; Mtolera, M.S.P.
This is a book about the macroscopic marine plants of Tanzania, namely the seaweeds or benthic macroscopic algae and the seagrasses, that are marine flowering plants. Having flourished in the 19th century and the beginning of the 20th century, taxonomic studies then became less popular and the emphasis of biological investigations turned to other aspects of biology. However, after realising how important the conservation of biodiversity is, we are now experiencing a new interest in a more naturalistic approach to biology. But today this “romantic” approach is often fuelled by extensive bioprospection, the search of new drugs and gene conservation for use in transgenic organisms of commercial value. This in itself could justify the production of a new book...
Tipo: Book
Palavras-chave: Marine plants; Seaweed; Seagrass.
Ano: 2003
URL: http://hdl.handle.net/1834/795

The Assessment of Water Quality and Pollution in Tanzania
Provedor de dados: 20
Autores: Mohammed, S.M.
The coastal area of Tanzania (Fig. 1) encompasses a number of habitats that include coral reefs, mangroves, seagrass beds, sand banks, wetlands and beaches, among others. In addition to being essential linkages in the overall functioning of the coastal area, these coastal habitats support various resources both living and non-living. In addition, for generations the coastal area has provided life support to coastal communities where such activities as fisheries and related activities have played an important role in the social and economic development of local communities. In recent years, coastal tourism and mariculture have immerged as being potentially among most important economic activities nationally. The well being of these habitats and resources...
Tipo: Preprint
Palavras-chave: Coral reefs; Mangroves; Seagrass; Wetlands; Beaches; Water quality; Pollution.
Ano: 2000
URL: http://hdl.handle.net/1834/183

Juvenile penaeid shrimp density, spatial distribution and size composition in four adjacent habitats within a Mangrove-Fringed Bay on Inhaca Island, Mozambique
Provedor de dados: 20
Autores: Macia, A.
The effects of habitat characteristics (mangrove creek, sandflat, mudflat and seagrass meadow) water salinity, temperature, and depth on the density, spatial distribution and size distribution of juveniles of five commercially important penaied shrimp species (Metapenaus monoceros, M. stebbingi, Fenneropenaeus indicus, Penaeus japonicus and P. semisulcatus) were investigated during a high shrimp recruitment peak lasting from January to June 2002, in four contiguous habitats within a non-estuarine mangrove bay at Saco da Inhaca, Inhaca Island, Southern Mozambique. A total of 14,976 specimens representing the five species were collected by means of a 1m beam-trawl fitted with a 2 mm mesh net with a cod-end. Every two weeks corresponding with spring tides on...
Tipo: Journal Contribution
Palavras-chave: METAPENAUS MONOCEROS; FENNEROPENAEUS INDICUS; METAPENAEUS STEBBINGI; PENAEUS  SEMISULCATUS; MARSUPENAEUS JAPONICUS; Distribution; Habitat; Juveniles; Salinity; Shrimp culture; Penaeid shrimp fisheries; Mangrove swamps; Seagrass; Mud flats; Distribution; Juveniles; Salinity.
Ano: 2004
URL: http://hdl.handle.net/1834/1121

Seasonal Variatrion of Cymodocea Nodeosa in the Ghar el Melh Lagoon (Tunisia) with reference to insolation, temperature and salinity effects
Provedor de dados: 20
Autores: Sghaier, Y. R.; Zakhama-Sraieb, R.; Charfi-Cheikhrouha, F.
Two sampling stations were selected in order to assess the response of the seagrass to lagoon conditions. Leaf growth was estimated using Zieman method and rhizome production was evaluated by marking rhizome terminals. The vegetative development of C. nodosa inside the lagoon at the limit of its distribution is different from that observed close to the communication channel with the sea. The growth of C. nodosa show a clear unimodal cycle in the two stations reaching maximum leaf development in summer. Shoot density decreased from 915 to 500 shoot m-2 from the communication channel toward the lagoon. The average total biomass varied between 241.6 ± 34 g DW m-2 and 413.8 ± 46 g DW m-2. Leaf plastochrone interval varied seasonally with an annual average of...
Tipo: Journal Contribution
Palavras-chave: Salinity; Biomass; Seagrass; Lagoons; Water temperature; Lagoons; Salinity; Biomass.
Ano: 2012
URL: http://hdl.handle.net/1834/5305

Données sur les caractéristiques et la phénologie de l’herbier de "Posidonia oceanica" (l.) delile sur les côtes de Mahdia (region est de la Tunisie)
Provedor de dados: 20
Autores: Mabrouk, L.; Hamza, A.; Sahraoui, H.; Bradai, M.N.
Le présent travail présente les résultats relatifs à la caractérisation de l’état de l’herbier de Posidonia oceanica de la zone de Mahdia, moyennant l’étude de la phénologie, au niveau de huit stations reparties sur cette zone pendant les saisons estivales et hivernales. Les herbiers de Posidonia oceanica prospectés de la région de Mahdia sont pour la plupart en très bon état; cependant, nous avons mis en évidence une mauvaise vitalité à Ben Ghayadha, à Sidi Salem et au la station Corniche. Le suivi de la variation saisonnière de l’état des herbiers fait apparaître une réduction de la longueur moyenne des feuilles adultes et intermédiaires, l’augmentation du nombre moyen des feuilles intermédiaires et une réduction de la surface foliaire depuis  l’été...
Tipo: Journal Contribution
Palavras-chave: Seagrass.
Ano: 2009
URL: http://hdl.handle.net/1834/4594

Posidonia Oceanica meadows along the eastern coast of Tunisia: feature and health status
Provedor de dados: 20
Autores: Sghaier, Y.R.; Zakhama-Sraieb, R.; Charfi Cheikhrouha, F.
La structure, la phénologie et la croissance des faisceaux des herbiers à Posidonia oceanica ont été étudiées dans quatre sites au niveau du centre Est de la Tunisie (Hergla, El Kantaoui, Monastir et Mahdia). La densité des faisceaux, le recouvrement et les paramètres phénologiques présentent une différence significative entre les sites et les profondeurs en relation avec l’intensité des activités humaines. Les herbiers les plus denses (441 à 984 faisceaux m-²) et les indices foliaires les plus élevés (8,5 à 13m2 m-²)) ont été enregistrés à Mahdia. Le nombre moyen des feuilles produites annuellement ne montre pas de différence significative entre les sites et les profondeurs étudiées. La croissance du rhizome de Posidonia oceanica est considérablement plus...
Tipo: Journal Contribution
Palavras-chave: Seagrass; Seaweeds.
Ano: 2011
URL: http://hdl.handle.net/1834/4738

Halophila baillonis Ascherson: first population dynamics data for the Southern Hemisphere
Provedor de dados: 42
Autores: Magalhães,Karine M.; Borges,João C.G.; Pitanga,Maria E.
The present paper presents the first population data for the Southern Hemisphere of the rare seagrass Halophila baillonis. The population studied is located in a calm, reef-protected area at depths ≤ 5 m, covering 12,000 m2 (400 m long by 30 m wide, oriented parallel to the coastline). The population generally demonstrated low shoot density and biomass during the rainy season, with significant differences between seasons, being found only for aboveground biomass. Despite the identification of this new population, the species continues to be considered rare along the Brazilian coast.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Vulnerable species; New population; Seagrass; Shoot density.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000200861

Seagrass biomass and their role as carbon reservoirs in the localities of San Andrés Island and La Guajira, Colombian Caribbean
Provedor de dados: 50
Autores: Acosta-Chaparro,Andrés; Sánchez-Valencia,Laura; Gómez-López,Diana Isabel; Gónzalez-Corredor,Juan David; Navas-Camacho,Raúl.
ABSTRACT Seagrass meadows have stood out for being very effective fixing atmospheric carbon, among others, due to their ability to produce plant biomass. Therefore, the values of shoot density (m2), biomass (cores) and carbon present in 12 locations with Thalassia testudinum at the Colombian Caribbean (La Guajira and San Andrés Island) were quantified. The biological samples were processed in laboratory until obtaining the values of aerial, underground and total dry weight, and the estimation of the carbon was stablishing from a ratio of 35 % of the dry biomass. Statistical tests were carried out to determine significant differences between the sites, highlighting the aerial biomass in La Guajira and the underground biomass in San Andrés. It was calculated...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Seagrass; Colombia; Biomass; Blue carbon.
Ano: 2022
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0122-97612022000100137