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1.
The Present work reports the study of the distribution of keratinophilic fungi isolated from 39 samples of soil collected in Brittany, France. Keratinophilic fungi were isolated from 35 (92.3%) of the samples studied. The most frequently found species wereFusarium moniliforme, Penicillium viridicatum and an unidentified species ofAcremonium. The other fungi isolated were members of the generaChrysosporium, Gliocladium, Mucor, Trichoderma andTrichophyton.  相似文献   

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Growth, diet and condition of goldsinny on the west coast of Scotland   总被引:1,自引:0,他引:1  
A study of seasonal, locational and sexual variations of growth, diet, somatic condition ( K s), gonadosomatic condition (GSI) and hepatosomatic condition (HSI), of the goldsinny wrasse, Ctenolabrus rupestris , was made on specimens taken from three areas (Millport, Oban and Luing) of the west coast of Scotland from May 1992 to June 1993. Capture throughout the year was by either baited creel or by anaesthetics applied underwater. Male goldsinny of age 1 year and older ranged in total length from 67-155 mm, total weight 3.8-58.8 g, and had a maximum age of 14+ years. Females of 1 year and older ranged in total length from 59-159 mm, total weight 2.4-65.4 g and had a maximum age of 20+ years. Juvenile (0 +) goldsinny were mostly of indeterminate sex, ranged in total length from 16-57 mm, and total weight 0.08-1.97 g. Female growth was slower than that of males for all three locations; growth of male and female goldsinny from Millport was slower than the respective sexes at the other two locations. Length-weight relationships varied with age and location. There were differences in K s, GSI, HSI and dietary trends associated with variation in season, sex and location. The implications of this variation are discussed in relation to the management of a sustainable goldsinny fishery.  相似文献   

4.
The karyotypes and cytogenetic characteristics of flatfishes species Paralichthys orbignyanus , Paralichthys patagonicus , Citarichthys spilopterus and Etropus crossotus (Paralichthyidae), Bothus ocellatus (Bothidae) and Symphurus tessellatus (Cynoglossidae) were investigated by conventional [Giemsa staining, C-banding, Ag- and chromomycin (CMA3)-stainings] and molecular [ in situ hybridization (ISH)] cytogenetic techniques. The results showed 2n = 46 and FN = 48 (2msm + 46sta) in P. orbignyanus , 2n = 46 and FN = 46 (46sta) in P. patagonicus , 2n = 26 and FN = 44 (18msm + 8sta) in C. spilopterus , 2n = 38 and FN = 64 (26msm + 12sta) in E. crossotus , 2n = 32 and FN = 50 (18msm + 14sta) in B. ocellatus , and 2n = 46 and FN = 62 (46msm + 62sta) in S. tessellatus . All species exhibited weak C-band positive segments in terminal and centromeric positions of some chromosome pairs. Silver staining of the nucleolus organizer regions (Ag-NOR) technique showed a single Ag-NOR-bearing chromosome pair in all species except E. crossotus . All these sites were CMA3 positive and showed clear ISH signals after probing with a 18S rRNA probe. Etropus crossotus presented until seven chromosomes with Ag-NORs and CMA3 positively stained segments in five chromosome pairs. Conversely only one chromosome pair was identified with the ISH experiments in this species. The available results show that the fishes of the order Pleuronectiformes experienced a marked chromosome evolution that included reduction in diploid number, mainly due to Robertsonian rearrangements, and several chromosome inversions.  相似文献   

5.
Data on the juvenile recruitment, growth and size at maturation of Lipophrys pholis in Portuguese waters are compared with the information available on the biology of this species at higher latitudes. In Portugal, recruitment extends for a much longer period, young fish grow faster and sexual maturation is earlier than at higher latitudes. There is a delay of 2–3 months between the appearance of the first eggs on the shore and the recruitment of the first juveniles to the pools.  相似文献   

6.
Gloaguen  J. C.  Gautier  N. 《Plant Ecology》1981,46(1):167-176
Plant Ecology - The main part of the heathlands in the Paimpont area (Morbihan, and Ille-et-Vilaine, France) was burnt during spring and summer 1976. The pattern development of the vegetation was...  相似文献   

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An ecological survey of the sandy beaches of the west coast of India revealed an important population of eurydicid isopods ( Eurydice peraticis Jones; E. indicis sp. nov.) of which one species is new to science. The systematics of these isopods are described, and their distribution on the Arabian Sea coast and the Indian beaches is discussed. Differences in their horizontal and vertical distribution on the beaches are explained in relation to the prevailing environmental conditions, of which exposure is the most important.  相似文献   

10.
On the Atlantic Moroccan coast, two species of pleuronectiform fish coexist, wedge sole ( Citharus linguatula ) a temperate species, and spotted flounder ( Dicohgoglossa cuneata ) a tropical one. These two species are the definitive host for Bothriocephalus andresi and Acanthocephaloïdes propinquus , respectively. A negative binomial fits the dispersion of B. andresi in the population of C. linguatula . The fish become parasitized between their first and third year, while still immature, with the highest abundances in the third year. After the fish become ichthyopagous, the level of infection drops drastically. We postulate that copepods are the sole source of infection. The presence of B. andresi in both Atlantic and Mediterranean populations of C. linguatula shows that the parasite follows the host during its migration along the Mediterranean coasts.
The prevalence of A. propinquus remains above 50% as a consequence of the large numbers of amphipods included in the diet of D. cuneata , regardless of the age of the fish or the season. The amphipods, Phtisica marina and Pariambus typicus are an important food and represent potential intermediate hosts for A. propinquus . The population dynamics of A. propinquus on the Atlantic Moroccan coasts are similar to those observed in parasite populations of Gobius niger in the Gulf of Lion (French Mediterranean). The observation of B. andresi and A. propinquus in both Moroccan Atlantic and Mediterranean fishes highlights the problem of the evolution of these parasite populations during the colonization of the Mediterranean by the hosts.  相似文献   

11.
The introduced macroalga Sargassum muticum (Yendo) Fensholt is currently observed along the coasts of Brittany. From February 2003 till June 2004, variations in density, reproductive status, length and phenolic content were assessed at three sites. Seasonal variability of the density was pronounced at two exposed sites (Fort Bloqué and Pointe du Diable), but absent at the sheltered site (Callot), where the macroalga was observed year-round. Thalli were generally longer in Summer (up to 73.2 ± 2.7 cm at Fort Bloqué), and had reproductive receptacles from May to September at Pointe du Diable, though only from June to September in the other stations (Callot and Fort Bloqué). Phenolic content was maximal during the reproductive period, which could be interpreted as chemical protection of the receptacles. Finally the collected data were used to explain the persistence of S. muticum and its proliferation in Brittany.  相似文献   

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Kelly  M.S.  Owen  P.V.  Pantazis  P. 《Hydrobiologia》2001,465(1-3):85-94
Sea urchin roe is a valuable food product. The commercial potential of Echinus esculentusL. (Echinodermata: Echinoidea) was assessed both by surveying field populations and gonad growth in response to artificial feeds. Urchins were collected from four locations on the Scottish west coast between June and August of 1998. The roe content was found to be of variable quality. A relatively low percentage of urchins (34.9%) had roe which was considered marketable both in terms of yield and colour. Urchins with a marketable yield of roe were found where algal growth or encrusting organisms were most prolific. Good roe colours and high roe yields were not necessarily coincident. The data suggest an urchin fishery is likely to be impractical economically. In tank-based trials large E. esculentus were fed either commercially available salmon feed, a pelletised urchin diet or the macroalgae Laminaria saccharina. Urchins fed the artificial diets increased in test diameter during the 24-week experiment. At the end of the trial urchins fed salmon feed had a significantly higher gonad and alimentary index than those in the other treatments. E. esculentusis able to successfully exploit a diet rich in animal-origin oils. The diets also influenced gonad colour. The proportion of urchins with marketable gonad colours was highest (85%) in the treatment receiving salmon feed. As this species appears robust in culture and as artificial diets promote somatic and gonadal growth, an investigation into the practicalities of a fully farmed approach to gonad production may be worthwhile.  相似文献   

14.
Summary 1. In the Gullmar Fjord (west coast of Sweden) bottom test squares had been sampled 40 years ago byGislén (1929–30). Studying the same squares in 1966, using skin diving equipment, has led to different results in regard to the fauna and flora found.2. If the old records are compared with a number of new ones, obtained from the same place and depth, the degree of variation encountered in the new samples may serve as indicator for assessing true differences between biocoenoses in 1926 and 1966.3. Differences between adjacent test squares depend mainly on the slope of the rock. Other factors which may affect the community structure over short distances are direction and light.4. Certain organisms settle on bottom areas where calm waters allow sedimentation.5. Increasing pollution demands sufficient and extensive registration of the actual situation in order to allow for comparisons. For this purpose even a lot of scattered observations can never be equal to numerous data from each of a few chosen places, which are representing the main trends in the sea bottom mosaic.
Quantitative Erfassung benthischer Organismen mit Hilfe der Tauchtechnik an der schwedischen Westküste
Kurzfassung DurchGislén (1929–1930) wurde eine umfassende ökologische Untersuchung der Epibiosen im Gullmar-Fjord an der schwedischen Skagerrak-Küste vorgenommen. Anhand zahlreicher Probenetnahmen durch einen Taucher wurde der Organismenbestand qualitativ und quantitativ untersucht. Im gleichen Gebiet wurden 40 Jahre später Vergleichsuntersuchungen durchgeführt, um Veränderungen in der Zusammensetzung und Verteilung der Biozönosen zu ermitteln. Parallele und divergierende Befunde hinsichtlich der Artenzusammensetzung der benthonischen Lebensgemeinschaften werden gegenübergestellt und diskutiert.
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15.
The abundance, structure, growth, and origin of clupeid populations in inshore waters of the west coast of Scotland were studied from April 1970 to October 1972. Clupeid populations in the area comprise mainly young fish. 0-group autumn-spawned herring, probably of Minch origin, move into the area about April and spring-spawned ones (Clyde origin) about June. The timing and the body length at which each group arrives in the area during the different years is the same. After the initial immigration, the distribution of both 0-group clupeids becomes localized.Herring populations in the sea-lochs and associated inshore waters are mainly 0-group fish, which are replaced each year by a new incoming brood. The sprat populations of the sea-lochs are dominated by the 0-group; in the more ‘open’ areas the populations comprise older individuals. Year-class distribution in the ‘open’ areas resemble that of the commercial fishery.The rate of increase of 0-group autumn-spawned herring is 3.68 mm/week and that of spring-spawned 0-group herring is 2.83 mm/week. The curves of growth of 0-group sprats of the 1970 and 1971 year-classes are different; the rate of increase in length, however, averages 3.55 mm/week for both year-classes and the differences are not significant.In sprats, after their first year of life a rapid increase in length takes place in the spring. This increase is thought to enable the majority of the population to reach the minimum size (88–90 mm) for initial gonadal maturation and thereby make them capable of reproducing in their second year of life.  相似文献   

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Nezumia liolepis and Nezumia stelgidolepis were collected during a National Marine Fisheries Service 1997 groundfish survey along the Pacific coast of North America. Bottom trawling was conducted from 188 to 1260 m depths. Nezumia liolepis were collected from 581 to 1247 m (3·4–5·7°C) and N. stelgidolepis from 285 to 555 m (6·0–8·4°C). The two species had distinct depth and temperature distributions and the majority of the specimens for each species came from narrow depth ranges. Nezumia stelgidolepis attains a larger pre-anal fin length (117 mm) than N. liolepis (83 mm), and age estimates from otolith ring counts indicate ages from 3 to 9 years for N. liolepis and 7 and 13 years for N. stelgidolepis from specimens collected. The gonads of N. liolepis were not reproductively active, and a single N. stelgidolepis possessed eggs of various sizes suggesting batch spawning. N. liolepis and N. stelgidolepis fed benthically, primarily on crustaceans such as amphipods, shrimp, mysids and polychaete worms. Although diet overlap was high, these two species appear to limit competition for resources by habitat separation.  相似文献   

17.
Studies on coccolithophorids in Mexico are rather scarce, probably due to the use of traditional methods for studying marine phytoplankton (e.g. collection, preservation and analysis). This is the first study of the coccolithophorid flora from west coast of Baja California, Mexico. Bottle samples (4 l) were taken at various depths (5, 25 and 50 m), at fixed stations located on perpendicular transects along the west coast of Baja California, considering three different zones: North, Central and South. A total of 32 samples were studied by optical and scanning electron microscopy, yielding 24 taxa identified (17 species and 5 nominal varieties, plus 2 different varieties). The coccolithophorid assemblages are considered subtropical and coastal (with many cosmopolitan taxa). Emiliania huxleyi and Gephyrocapsa oceanica were the most abundant (relative abundance) and widespread species in the study area. We report 15 new records for the Mexican Pacific. The zonal and vertical distribution of some taxa are briefly discussed, as well as the taxonomy of Rhabdosphaera claviger, Helicosphaera carteri, H. hyalina and related taxa.  相似文献   

18.
Watershed nitrogen input and riverine export on the west coast of the US   总被引:1,自引:0,他引:1  
This study evaluated the sources, sinks, and factors controlling net export of nitrogen (N) from watersheds on the west coast of the US. We calculated input of new N to 22 watersheds for 1992 and 2002. 1992 inputs ranged from 541 to 11,644 kg N km−2 year−1, with an overall area-weighted average of 1,870 kg N km−2 year−1. In 2002, the range of inputs was 490–10,875 kg N km−2 year−1, averaging 2,158 kg N km−2 year−1. Fertilizer was the most important source of new N, averaging 956 (1992) and 1,073 kg N km−2 year−1 (2002). Atmospheric deposition was the next most important input, averaging 833 (1992) and 717 kg N km−2 year−1 (2002), followed by biological N fixation in agricultural lands. Riverine N export, calculated based on measurements taken at the furthest downstream USGS water quality monitoring station, averaged 165 (1992) and 196 kg N km−2 year−1 (2002), although data were available for only 7 watersheds at the latter time point. Downstream riverine N export was correlated with variations in streamflow (export = 0.94 × streamflow − 5.65, R 2 = 0.66), with N inputs explaining an additional 16% of the variance (export = 1.06 × streamflow + 0.06 × input − 227.78, R 2 = 0.82). The percentage of N input that is exported averaged 12%. Percent export was also related to streamflow (%export = 0.05 × streamflow − 2.61, R 2 = 0.60). The correlations with streamflow are likely a result of its large dynamic range in these systems. However, the processes that control watershed N export are not yet completely understood.  相似文献   

19.
Three species of penaeid shrimp, Fenneropenaeus indicus, Penaeus monodon and P. semisulcatus, found in trawler catches off the west coast of Madagascar were infected with microsporidian parasites. The infections were evident as muscular lesions with a cottony appearance when abundant. Spore size (2.6 x 1.6 microm) and morphology (ovoid) for the parasites infecting both F. indicus and P. semisulcatus were not significantly different, suggesting that they might be the same microsporidian species. Spore size (1.4 x 1.1 microm) and morphology (sub-globose to ovoid) in P. monodon infections were significantly different from those in the other 2 shrimp species, suggesting that it was a different parasite. The presence of microsporidians in this biogeographical zone means that there is a potential risk of infections of cultured shrimp in farms situated in the vicinity. This must be assessed by increasing current knowledge of the parasites.  相似文献   

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