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| Registros recuperados: 41 | |
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| Quaresma,Adriano Costa; Jardim,Mário Augusto Gonçalves. |
| Vascular epiphytes constitute a life form that is important to maintaining the biological diversity of forest ecosystems, because they provide food resources and specialized microenvironments for fauna in the forest canopy. This study aimed to describe the floristic composition and ecological aspects of vascular epiphytes occurring in the restingas (coastal woodlands) within the Algodoal-Maiandeua Environmentally Protected Area, located in the municipality of Maracanã, in the state of Pará, Brazil. We sampled five 50 × 50 m plots (three in dry restinga forest and two in floodplain restinga forest), the sampled area therefore totaling 1.25 ha. In the plots sampled, vascular epiphytes were identified and described according to their frequency, abundance,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Functional group; Amazon coast; Epiphytism; Vertical distribution. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062014000100007 |
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| Lira,Giulliari A. S. T.; Araújo,Elcida L.; Bittencourt-Oliveira,Maria Do Carmo; Moura,Ariadne N.. |
| The present study reports the phytoplankton abundance, dominance and co-existence relationships in the eutrophic Carpina reservoir, Pernambuco, Brazil. Sampling was carried out at six different depths bimonthly at a single reservoir spanning two climatic periods: dry season (January, September, and November 2006) and rainy season (March, May, and July 2006). Density, abundance, dominance, specific diversity and equitability of the community were determined, along with chlorophyll a, and physical and chemical variables of the environment. Eight species were considered abundant, and their densities corresponded to more than 90% of the total phytoplankton community quantified. Cyanobacteria represented more than 80% of this density. Cylindrospermopsis... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Carpina reservoir; Cylindrospermopsis raciborskii; Cyanobacteria; Limnological characteristics; Phytoplankton structure; Vertical distribution. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652011000400018 |
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| Becerra,Alejandra; Bartoloni,Norberto; Cofré,Noelia; Soteras,Florencia; Cabello,Marta. |
| Arbuscular mycorrhizal fungi (AMF) colonize land plants in every ecosystem, even extreme conditions such as saline soils. In the present work we report for the first time the mycorrhizal status and the vertical fungal distribution of AMF spores present in the rhizospheric soil samples of four species of Chenopodiaceae (Allenrolfea patagonica, Atriplex argentina, Heterostachys ritteriana and Suaeda divaricata) at five different depths in two saline of central Argentina. Roots showed medium, low or no colonization (0-50%). Nineteen morphologically distinctive AMF species were recovered. The number of AMF spores ranged between 3 and 1162 per 100 g dry soil, and AMF spore number decreased as depth increased at both sites. The highest spore number was recorded... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Arbuscular mycorrhiza; Saline environments; Soil profile; Vertical distribution; Mycorrhizal status. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822014000200029 |
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| Mendonça,Marcos Marques; Picapedra,Pablo Henrique dos Santos; Ferronato,Michelli Caroline; Sanches,Paulo Vanderlei. |
| ABSTRACT Based on the hypothesis that diel vertical migration (DVM) is a mechanism of predator avoidance, the objective of the present study was to test for the occurrence of DVM in planktivorous fish larvae of Hypophthalmus edentatus (Spix, 1829) (Siluriformes, Pimelodidae) and Plagioscion squamosissimus (Heckel, 1840) (Perciformes, Sciaenidae), and zooplankton (rotifers, cladocerans and copepods) in an isolated tropical lagoon in the floodplain of the Upper Paraná River, Brazil (region of Parque Nacional de Ilha Grande). We investigated spatial overlap between predators (planktivorous fish larvae) and prey (zooplankton), and tested which physical and chemical variables of the water are related to the DVM of the studied communities. We performed nocturnal... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Vertical distribution; Spatial overlap; Predator-prey interactions; Rotifers; Microcrustaceans. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212015000200174 |
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| Petitgas, Pierre; Magri Hoeltzener, Stephanie; Lazure, Pascal. |
| Modelling the vertical distribution of fish eggs is important when assessing fish stocks with egg production methods and for monitoring the reproductive potential of fish populations. Fish eggs are passive particles and their vertical distribution is determined by a few parameters such as egg density, egg diameter, wind- and tide-induced turbulence, and vertical hydrographic structure. A one-dimensional vertical biophysical, numerical model was developed which was adapted to the hydrography of shelf seas under the influence of tidal currents, wind-induced circulation, and river discharges. The biological part of the model parameterized the ascent velocity of the egg as a function of egg properties (diameter, density) and water properties (density,... |
| Tipo: Text |
Palavras-chave: Vertical distribution; Sprat; Sardine; Fish egg buoyancy; CUFES; Biophysical coupling; Anchovy. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2277.pdf |
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| Picheral, Marc; Guidi, Lionel; Stemmann, Lars; Karl, David M.; Iddaoud, Ghizlaine; Gorsky, Gabriel. |
| The Underwater Vision Profiler (UVP) was developed to quantify the vertical distribution of macroscopic particles and zooplankton > 100 mu m in size. The smaller size limit is fixed by optical resolution, whereas the larger size limit is determined by the volume of water illuminated per image. The new fifth generation instrument (UVP5) is compact (30 kg in air) and operates either as a stand-alone instrument with an independent power supply for use on a mooring or free-drifting array, or as a component of a Conductivity, Temperature, and Depth (CTD)-rosette package. Images are recorded at a frequency up to 6 Hz. If the UVP5 is interfaced with a CTD, these images are acquired and analyzed in real time. Images are recorded every 20 cm at the 1 m s(-1)... |
| Tipo: Text |
Palavras-chave: Video plankton recorder; Marine snow; MU-M; Vertical distribution; Aggregate dynamics; In situ; System; Ocean; Flux; Phytoplankton. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00133/24413/22426.pdf |
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| Caumette, P. |
| In the deepest parts of the estuarine region of Ebrie Lagoon (Abidjan Africa, (5 degree N, 4 degree W) stratified conditions have been observed during the rainy season (May to Nov.), owing to salinity differences between oxic and anoxic layers. At the interface, 3-4 m depth, phototrophic bacteria (Chromatium, Chlorobium and Pelodictyon ) developed, forming a brown layer due to their different pigments. Their production has been estimated at 41% of the total photosynthetic production during high stratification (Sep. 1981) and their biomass was used by the copepod population for 40 to 60% of its diet. During the dry season, the water column became homogeneous and oxygen was detected to 6m depth. The brown layer of phototrophic bacteria disappeared, as well... |
| Tipo: Text |
Palavras-chave: Chlorobium; Chromatium; Primary production; Photosynthesis; Estuaries; Seasonal variations; Plankton; Stratification; Vertical distribution; Bacteria; Coastal lagoons; Trophic relationships; Biomass. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-957.pdf |
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| Andersen, V; Francois, F; Sardou, J; Picheral, M; Scotto, M; Nival, Paul. |
| Vertical distributions and diel migrations at nineteen stations located in the Ligurian and Tyrrhenian Seas (northwestem Mediterranean) are described in detail and compared for the main species of micronekton and macroplankton. Sampling was performed in April 1994 in the 0-700 m water column in most cases, down to 350, 450 or 550 m for the coastal or relatively shallow sites. Most of the twenty species showed similar distributions throughout the sampled area, either non-diel-migrating distributions such as the euphausiid Stylocheiron longicorne and the fish Cyclothone braueri, or clear diel-migrant behaviour (e.g. the siphonophore Chelophyes appendiculata and the euphausiid Euphausia krohni). Four species, the siphonophore Lensia conoidea, the pteropods... |
| Tipo: Text |
Palavras-chave: Distribution verticale; Macroplancton; Micronecton; Mer Méditerranée; Mer Tyrrhénienne; Vertical distribution; Macroplankton; Micronekton; Mediterranean Sea; Tyrrhenian Sea. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00325/43650/43222.pdf |
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| Sardou, J; Etienne, M; Andersen, V. |
| Based on monthly samplings over an entire year, variations of abundance, vertical distributions and diel vertical migrations are described in the 0-1000 m water column in a coastal area of the Northwestern Mediterranean Sea for the main pelagic invertebrates. Detailed results are given for 21 species of macrozooplankton and micronekton. On an annual basis, the most numerous species by numbers comprised the euphausiid Meganyctiphanes norvegica, the pteropod Cavolinia inflexa, the siphonophores Abylopsis tetragona and Chelophyes appendiculata, the crustacean decapods Sergestes arcticus and Pasiphaea sivado, and the salps Salpa fusiformis and Thalia democratica. Species of the same genus, such as Sergestes arcticus, S. corniculum and S. robustus or Pasiphaea... |
| Tipo: Text |
Palavras-chave: Seasonal cycle; Vertical distribution; Macroplankton; Micronekton. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00096/20732/18369.pdf |
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| Thomas, Y.; Garen, Pierre; Courties, C.; Charpy, L.. |
| Spatial and temporal scales of variability in phyto- and bacterioplankton abundance were investigated in a deep atoll lagoon (Ahe, French Polynesia), Ahe Lagoon showed a classical phytoplankton composition, but its picophytoplankton (Prochlorococcus, Synechococcus and picoeukaryotes) concentrations are higher than the mean for Polynesian atoll lagoons. Phyto- and bacterioplankton descriptors were highly variable, with mean CVs of >20% in most cases: day night, day-to-day, vertical, lagoonal and seasonal. Phytoplankton biomass, which was estimated by in vivo fluorescence, was higher in the deep layer than in the upper layer. This pattern was detected on a day night scale, showing transitory vertical gradients, and through long-term events that were... |
| Tipo: Text |
Palavras-chave: Flow cytometry; Picophytoplankton; Nanophytoplankton; Bacterioplankton; Vertical distribution; Day-to-day dynamics; Large-scale heterogeneity; Deep atoll lagoon; French Polynesia. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00003/11425/7963.pdf |
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| Weikert, H; Koppelmann, R. |
| Differences in the vertical distribution of bathypelagic zooplankton in the open northeast Atlantic and in the partially landlocked Levantine and Red Seas were re-evaluated to provide an interoceanic comparison. The decrease in zooplankton abundance with depth was most pronounced in the Red Sea and least evident in the northeast Atlantic. The Levantine Sea showed intermediate characteristics. The data plotted on a semi-log scale against a linear change in depth revealed a reduced rate of decrease in the zooplankton concentration with depth in the deep bathypelagic zone of the northeast Atlantic and the Levantine Sea. This pattern was also found for vertical profiles of micronekton abundance in the southeast Pacific. In the Red Sea, the decrease was... |
| Tipo: Text |
Palavras-chave: Bathypelagic zooplankton; Interoceanic comparison; Vertical distribution; Vertical flux. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00096/20733/18370.pdf |
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| Amezcua,Felipe; Rodríguez-Preciado,José Alberto; Calderón-Pérez,Antonio; Rendón-Rodríguez,Sergio; Green,Lucinda; Chazarreta,Carlo Javier. |
| Abstract The influence of salinity and temperature on larval fish assemblages, as well as, temporal and vertical patterns on larval fish assemblages off the inlet of the Presidio River, southeast coast of the Gulf of California were evaluated. Samplings for ichthyoplankton and environmental parameter measurements were carried out at three depths, in five sampling sites, during September and December 1994, and April and June 1995. Anchovies and herrings (Clupeiformes) were the most abundant larval fish accounting for 77% of the total abundance. A significant relationship between salinity and the abundance of larval herrings (Opisthonema medirastre and O. dovii) and between the water temperature and the abundance of the weakfish (Cynoscion reticulatus) was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Estuaries; Ichthyoplankton; Larval fish distribution; Sinaloa; Vertical distribution. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252020000100212 |
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| 谷, 昌幸; 溝田, 千尋; 八木, 哲生; 加藤, 拓; 小池, 正徳; TANI, Masayuki; MIZOTA, Chihiro; YAGl, Tetsuo; KATO, Taku; KOIKE, Masanori. |
| 本研究では，十勝地域の農耕地，とくに普通畑土壌にお ける肥培管理などが土壌へのリン酸蓄積量とその形態に及ぼす影響を明らかにすることを目的とした.畑地およひ隣接する未耕地において土壌断面調査と試料採取を行い，土壌中の全リン酸含量および各種形態別リン酸含量の垂直分布を調べたさらに，仮比重および未耕地と農耕地における土壌の層厚差を考慮し正味のリン酸蓄積量を調べた. 1)淡色黒ボク土，厚層黒ポク土，および普通褐色低地 土のいずれの農耕地土壌においても，施肥などに由来する余剰リン酸は耕起の影響を受けた表層30~40cm までの 作土層に蓄積し，物理的に撹拌および混和されることにより作土層全体に比較的均一に分布した. 2)未耕地土壌との垂直分布の比較から，黒ボク土では 余剰リン酸が下層へ溶脱せず作土層にのみ蓄積し，褐色低地土では一部が下層へ溶脱していると考えられた. 3) 農耕地における正味のリン酸蓄積量は，黒ボク土で 著しく多く，年平均130kgha-1以上であった. 大部分は，フッ化物イオンの配位子交換能により抽出され，活性アルミニウムなどに特異吸着されていると考えられた褐色低地土では蓄積量が少なく，弱酸可溶のリン酸水素カルシウムや，弱い配位子交換反応で抽出可能な非品質リン酸アルミニウムなどの沈殿として蓄積していると考えられた.Heavy application of phosphate fertilizer and subsequent phosphate accumulation in arable soilsï¼ especially Andosolsï¼ are critical issues for sustainable agriculture in ]apan. The effects of... |
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Palavras-chave: リン酸蓄積; 黒ボク土; 褐色低地土; 層厚差; 垂直分布; Andosols; Brown Lowland soils; Soil thickness; Phosphate accumulation; Vertical distribution. |
| Ano: 2010 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2696 |
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| Casarsa, L.; Madirolas, A.. |
| The normal behavioral patterns of several fish species is altered during trawling affecting the fish spatial distribution. Sonar methods were carried out in this research work in order to study the reaction of reproductive concentrations of the Argentine hake (Merluccius hubbsi) during mid-water and bottom fishing trawls. Observations made from a trawl sonar mounted on the headrope of an ENGEL (35 m) bottom trawl, showed that this species concentrates at the lower-central sector of the net mouth. During daytime trawls fish schools with a vertical distribution exceeding ten meters were observed entering the trawl within the first two meters from the bottom. Some observations during pelagic trawls carried out at night, showed no specific pattern at the net... |
| Tipo: Journal Contribution |
Palavras-chave: Behaviour; Bottom trawling; Sonar; Echo surveys; Vertical distribution; Behaviour; Http://aims.fao.org/aos/agrovoc/c_868. |
| Ano: 2007 |
URL: http://hdl.handle.net/1834/2517 |
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| Registros recuperados: 41 | |
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