scholarly journals Offshore distribution patterns of the cyanobacterium Trichodesmium erythraeum ehrenberg and associated phyto- and bacterioplankton in the southern Atlantic coast (Paraná, Brazil)

2006 ◽  
Vol 49 (2) ◽  
pp. 323-337 ◽  
Author(s):  
Adriana Siqueira ◽  
Hedda Elisabeth Kolm ◽  
Frederico Pereira Brandini
Keyword(s):  
Surface Water ◽  
Atlantic Coast ◽  
Bacterial Biomass ◽  
Distribution Patterns ◽  
High Light ◽  
Sampling Area ◽  
Trichodesmium Erythraeum ◽  
Anabaena Sp ◽  
Pennate Diatoms ◽  
Total Bacteria

Studies were carried out on Thrichodesmium erythraeum occurring on the inner shelf in the state of Paraná, Brazil. Temperature, salinity, rainfall, wind velocity, total bacteria, bacterial biomass, chlorophyll-a, phytoplankton, Anabaena sp., Merismopedia sp. and T. erythraeum densities were measured in surface water. Centric and pennate diatoms, Anabaena sp. and Merismopedia sp. were most abundant at 15 m isobath, while dinoflagellate abundance was relatively constant among stations. Similarly, total bacterial densities were relatively homogeneous throughout the sampling area, suggesting that blooms of T. erythraeum were not yet in the senescent phase. Results showed that T. erythraeum was capable of surviving in relatively inhospitable environmental conditions, due to its ability to fix nitrogen and to photosynthesis at high light intensities.

A new species of Dichelyne (Nematoda, Cucullanidae) parasitizing sciaenid fishes from off the South American Atlantic coast

2009 ◽  
Vol 54 (1) ◽  
Author(s):  
Juan Timi ◽  
Ana Lanfranchi ◽  
Luiz Tavares ◽  
José Luque
Keyword(s):  
New Species ◽  
Atlantic Coast ◽  
Length Distribution ◽  
Distribution Patterns ◽  
Nematode Species ◽  
Valid Species ◽  
South American ◽  
Type Specimens ◽  
Pacific Waters ◽  
A New Species

AbstractA new nematode species Dichelyne (Cucullanellus) sciaenidicola sp. nov. is described based on specimens collected from the Whitemouth croaker Micropogonias furnieri (Desmarest) and the Argentine croaker Umbrina canosai Berg, from coastal waters of Argentina and Brazil. These nematodes were firstly identified as D. (C.) elongatus (Törnquist, 1931), a commonly reported species from M. furnieri in South American Atlantic waters. However, other species of Dichelyne have so far been reported from this host in the same area, namely D. (C.) rodriguesi (Pinto, Fábio et Noronha, 1970), D. (C.) amaruincai (Freitas, Vicente et Ibañez, 1969) and D. (Dichelyne) micropogonii Pereira et Costa, 1996. A careful re-examination of these parasites, as well as of type specimens of all species reported from M. furnieri, revealed that these nematodes represented a new species. The new species is distinguished from most of its congeners by having papillae 5–7 and 9 forming a subventral line close to cloaca, this feature is shared with other 6 species [D. (C.) dichelyneformis (Szidat, 1950), D. (C.) fraseri (Baylis, 1929), D. (C.) abbreviatus (Rudolphi, 1819), D. (C.) adriaticus (Törnquist, 1931), D. (C.) minutus (Rudolphi, 1819) and D. (C.) mariajuliae Alarcos, Timi, Etchegoin et Sardella, 2006)], which are readily distinguished by their body size, spicules length, distribution patterns of other papillae and position of the excretory pore and deirids. Also, D. (C.) elongatus from Umbrina canariensis (Valenciennes) from West Africa is established as a new species Dichelyne (Cucullanellus) yvonnecampanae sp. nov.; D. (C.) amaruincai from Pacific waters is considered as a valid species, D. (D.) micropogonii is regarded as species inquirendae and D. (C.) rodriguesi is identified as Cucullanus sp.

Small-scale distribution and salinity response of Juniperus virginiana on an Atlantic Coast barrier island

1997 ◽  
Vol 75 (1) ◽  
pp. 77-85 ◽  
Author(s):  
David W. Martin ◽  
Donald R. Young
Keyword(s):  
Ground Water ◽  
Atlantic Coast ◽  
Barrier Island ◽  
Distribution Patterns ◽  
Small Scale ◽  
Juniperus Virginiana ◽  
Plant Responses ◽  
Rooting Zone ◽  
Red Cedar ◽  
Salinity Response

A field and laboratory study examined the hypothesis that the small-scale distribution pattern of Juniperus virginiana on barrier islands is related to salinity patterns and plant responses to salinity. Temporal (May – October) and spatial variability in ground water availability, ground water salinity, and total soil chlorides were quantified across a Virginia barrier island. Groundwater depth and salinity increased throughout the summer; microtopographic position and location on the island also affected soil salinities. Highest salinities occurred near the ocean side beach and bay side marsh, as well as in low lying swales that flood during extreme high tides or storms. Median rooting zone chloride level for J. virginiana was 54 μg/g. In contrast, laboratory germination and growth studies indicated that J. virginiana was significantly affected only at high salinity levels (1000 and 1400 μg/g), suggesting that salinity is not the only factor regulating small-scale distribution patterns. The broad tolerance to salinity may account for the abundance of J. virginiana in coastal environments. Key words: barrier island, eastern red cedar, Juniperus virginiana, salinity response, water relations.

Ekman Transport and Zooplankton Concentration in the North Pacific Ocean

1967 ◽  
Vol 24 (3) ◽  
pp. 581-594 ◽  
Author(s):  
W. Percy Wickett
Keyword(s):  
Surface Water ◽  
Bering Sea ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Ekman Transport ◽  
Sampling Area ◽  
The North ◽  
Western Bering Sea ◽  
North And South ◽  
The North Pacific

Annual concentrations of zooplankton off California varied directly, and concentrations in the western Bering Sea varied indirectly with calculated southerly components of Ekman transport in the previous year at 50°N,140°W. This point is in the area in which surface subarctic water and the deeper currents divide north and south. The underlying geostrophic flow requires approximately 1 year to reach each downstream sampling area. Summer concentrations of zooplankton at Ocean Station P, 50°N,145°W, varied with southerly and westerly components at 50°N,160°W during the previous winter. Fifty to sixty per cent of the variance of the annual concentration in zooplankton appears to be due to advection of surface water.

scholarly journals COMPOSIÇÃO E DISTRIBUIÇÃO DO FITOPLÂNCTON EM ÁREAS COSTEIRAS E OCEÂNICAS DA REOIAO SUESTE DO BRASIL

1986 ◽  
Vol 1 (3) ◽  
Author(s):  
Frederico Pereira Brandini ◽  
Cristine Louise Braum Moraes
Keyword(s):  
Great Influence ◽  
Nutrient Concentrations ◽  
Brazilian Coast ◽  
Trichodesmium Erythraeum ◽  
Tropical Water ◽  
Brazil Current ◽  
Total Phytoplankton ◽  
Phosphate Nitrate ◽  
Anabaena Sp ◽  
Oligotrophic Condition

Total phytoplankton samples and hydrographical parameters were collected from the surface of 16 stations located in the southeastern sector of the brazilian coast during the autumn cruise of the R/V “ Almirante Saldanha” . The limits of temperature (22 — 25°C) and salinity (35,0 — 37,1 x 10‘s) observed indicated the great influence of the Tropical Water over the sampling area where the oligotrophic condition is certainly due to the low nutrient concentrations of this watermass. Phosphate, nitrate and silicate ranged from 0.0 to 0.63, 1.41 to 5.69 and from 4.10 to 25,25 ftg-at.r1, respectively.The most frequent diatoms were Coscinodiscus spp, Coscinosira sp, Pleurosigma sp, Pseudoeunotia doliolus, Thalassionema nitzschioides, Thalassiothrix frauenfeldii and T. mediterrânea, among 49 species observed. Prorocentrum and Protoperidinium spp dominated the dinoflagellate population although the genus Ceratium was represented by a greater number of species. Cyanophycean cells were abundant in coastal (Anabaena sp) and oceanic (Trichodesmium erythraeum) samples.The phytoplankton community was numerically dominated by nanoplanktonic organisms like phytoflagellates (including monads) and the coccolithophorid Coccolithus huxleyi. The phytoplankton association observed in the present study is typical of oligotrophic warm waters of the Brazil Current. Amostras de fitoplâncton total e parâmetros hidrográficos foram obtidos na superfície de 16 estações localizadas no setor sudeste da costa brasileira durante o outono de 1983. Os limites de temperatura (22 — 25°C) e salinidade (35,0 — 37,1 x10 “) observados indicaram a influência da Água Tropical na área estudada onde as condições oligotróficas são devidas à baixa concentração de nutrientes nessa massa d’água. Fosfato, nitrato e silicato variaram entre 0,0 e 0,63, 1,41 e 5,69, e 4,10 e 25,25 /ig-at.r1, respectivamente.As diatomáceas mais freqüentes foram Coscinodiscus spp, Coscinosira sp, Fleurosigma sp, Pseudoeunotia doliolus, Thalassionema nitszchioides, Thalassiothrix frauenfeldii e T. mediterrânea, dentre as 49 espécies observadas. Prorocentrum e Protoperidinrum spp dominaram a população de dinoflagelados apesar do gênero Ceratium ter apresentado o maior número deespécies. As cianofíceas Anabaena sp e Oscillatoria (=Trichodesmium) erythraeum foram abundantes nas amostras costeiras e oceânicas.A comuindade fitoplanctônica foi numericamente dominada por organismos do nanoplâncton, tais como fitoflagelados (incluindo-se mônadas) e o cocolitoforídeo Coccolithus huxleyi. A associação fitoplanctônica observada no presente trabalho é típica das águas quentes e oligotróficas da Corrente do Brasil.

scholarly journals Invasion Dynamics of A Termite, Reticulitermes flavipes, at Different Spatial Scales in France

Insects ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 30
Author(s):  
Elfie Perdereau ◽  
Guillaume Baudouin ◽  
Stéphanie Bankhead-Dronnet ◽  
Zoé Chevalier ◽  
Marie Zimmermann ◽  
...  
Keyword(s):  
Urban Areas ◽  
18Th Century ◽  
Spatial Scales ◽  
Atlantic Coast ◽  
Regional Scale ◽  
Distribution Patterns ◽  
Reticulitermes Flavipes ◽  
Railway Network ◽  
Invasion Dynamics ◽  
Large Colony

Termites are social insects that can also be major pests. A well-known problem species is the subterranean termite, Reticulitermes flavipes. It is invasive in France and is thought to have arrived from Louisiana during the 18th century. While the putative source of French populations has been identified, little is known about how the termite spread following its establishment. Here, we examined expansion patterns at different spatial scales in urban areas to clarify how R. flavipes spread in France. Based on our analyses of phylogeography and population genetics, results suggest a scenario of successive introductions into the Charente-Maritime region, on the Atlantic Coast. Two major expansion fronts formed: one that spread toward the northeast and the other toward the southeast. At the regional scale, different spatial and genetic distribution patterns were observed: there was heterogeneity in Île-de-France and aggregation in Centre-Val de Loire. At the local scale, we found that our three focal urban sites each formed a single large colony that contained several secondary reproductives. Our findings represent a second step in efforts to reconstruct termite’s invasion dynamics. They also highlight the role that may have been played by the French railway network in transporting termites over long distances.

Surface Water Temperatures of the Canadian Atlantic Coast

1939 ◽  
Vol 4b (5) ◽  
pp. 378-391 ◽  
Author(s):  
H. B. Hachey
Keyword(s):  
Surface Water ◽  
General Type ◽  
Atlantic Coast ◽  
Smooth Curve ◽  
Temperature Curve

Monthly mean surface water temperatures, based on observations from 1926 to 1935 are used to determine normal monthly mean temperatures for eight points on the Canadian Atlantic coast. Sine curves are found to fit the data for all points, with one exception. The general type of temperature curve determined by daily observations divides the regions of observation into those represented by a smooth curve, those by an erratic type, and those showing sharp but regular changes in temperatures from day to day.

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