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Consulta: subjectFacets:"Nematoda [Nematodes]"
Registros recuperados: 22
Data/hora: 08/06/2017 18:09:55
A model of nematode dynamics in the Westerschelde Estuary
Provedor de dados: 27
Autores: Li, J.; Vincx, M.; Herman, P.M.J.
We developed a time dynamic model to investigate the temporal dynamics of nematode community in the brackish zone of the
Westerschelde Estuary. The biomass of four nematode feeding groups observed from March 1991 to February 1992 is used to
calibrate the model. Using environmental data as the input, the model predicts the temporal modification and interrelation of four
nematode feeding groups. Nematodes achieve a dominant position in the community because of their lower loss rate (in
respiration, excretion and natural death). Predators which are deposit-feeding macrobenthos control the variations of dominant
nematodes, such as omnivores and non-selective deposit feeders. Food availability causes modification only for rare nematodes
such as epigrowth...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Diatoms; Ecology; Food; Light; Marine nematodes; Meiobenthos; Population dynamics; Predation; Respiration;
Temperature; Nematoda [Nematodes].
Ano: 1996
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7284
A re-evaluation of marine nematode productivity
Provedor de dados: 27
Autores: Vranken, G.; Herman, P.M.J.; Vincx, M.; Heip, C.H.R.
Nematodes are the most abundant multicellular animals in marine sediments but their role in the benthos has not been properly
quantified yet. In nearly all energy-flow budgets of marine systems their annual production P is given as about nine times their
biomass B and their part in the total energy-flow is consequently estimated as anywhere between 3 and 30% of the total (carbon)
input in the benthic system. Our laboratory experiments demonstrate that nematode productivity is much higher than P/B ~ 9 per
year and may reach values of over 60 for bacterial grazers. To obtain more reliable estimates for field populations we propose a
regression equation relating egg-to-egg development time T<sub>min</sub> to temperature (t) and adult female
weight...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biological production; Mathematical models; Meiobenthos; Nematoda [Nematodes].
Ano: 1986
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3576
A seasonally varying biotope at Signy Island, Antarctic: implications for meiofaunal structure
Provedor de dados: 27
Autores: Vanhove, S.; Beghyn, M.; Van Gansbeke, D.; Bullough, L.W.; Vincx, M.
Under the typical high-latitude conditions of temperature, productivity and settlement of chlorophyll and phaeophytin to the
sediment, many benthic organisms in the Antarctic show strong seasonal variation. Although meiofauna comprise an important
component of the southpolar benthic ecosystem, our knowledge of them is limited. The metazoan meiofauna and the surrounding
sediments were studied fortnightly for 18 mo in a shallow bay at Signy Island (Factory Cove, South Orkneys, Antarctica) to test
whether and how the temporal variability of the environment influenced meiobenthos dynamics. By examination of the
distribution of the abundance and biomass of the total community, the density of higher taxonomic groups, and of individual
dominant nematode genera...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Benthos; Biomass; Population density; Seasonal variations; Sediment analysis; Trophic relationships; Copepoda
[copepods]; Nematoda [Nematodes]; Ostracoda.
Ano: 2000
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=6138
Calculation of the intrinsic rate of natural increase, r<sub>m</sub>, with
<i>Rhabditis marina</i> Bastian 1865 (Nematoda)
Provedor de dados: 27
Autores: Vranken, G.; Heip, C.H.R.
The life-cycle of <i>Rhabditis marina</i> Bastian 1865 was studied at 25°C and 20 promille salinity. The following
demographic parameters were computed from life-table data: the intrinsic rate of natural increase (r<sub>m</sub>) =
0.914 day; net reproductivity (R<sub>0</sub>) = 400; minimum generation time (T<sub>min</sub>) =
4.5 days; cohort generation time (T<sub>c</sub>) = 7.2 days; mean generation time (T) = 6.6 days; and the age of an
adult female when a median egg is deposited (T) = 6.1 days. Several approximate equations used to estimate
r<sub>m</sub> were compared with these life-table calculations. Some give erroneous estimations and should be used
with extreme caution. For...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Population characteristics; Nematoda [Nematodes]; Rhabditis marina.
Ano: 1983
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3260
<i>Polkepsilonema mombasae</i> gen. et sp. n. and <i>Pternepsilonema
servaesae</i> gen. et sp. n. (Nematoda, Epsilonematidae) from East African coasts
Provedor de dados: 27
Autores: Verschelde, D.; Vincx, M.
Two new genera and species from Kenyan tidal areas, <i>Polkepsilonema mombasae</i> gen. et sp.n. and
<i>Pternepsilonema servaesae</i> gen. et sp.n., are described. Both are characterized by the presence of at least
fourteen subcephalic setae and by thick thorns on the ventral body region of males. In the first genus, eight to ten subcephalic
setae are situated at the posterior edge of the rostrum, and the ambulatory setae are straight. A key of the 13 genera of the
Epsilonematidae is presented.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Epsilonematidae; Nematoda [Nematodes]; Polkepsilonema mombasae; Pternepsilonema servaesae.
Ano: 1993
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2797
<i>Procamacolaimus tubifer</i> Gerlach, 1953, <i>Procamacolaimus
africanus</i> sp. nov. and <i>Eontolaimus capensis</i> gen.nov., sp.nov.
(Nematoda, Leptolaimidae) from Southern Africa
Provedor de dados: 27
Autores: Furstenberg, J.P.; Vincx, M.
A female and three males of <i>Procamacolaimus tubifer</i> Gerlach, 1953 are described and illustrated from Cape
Receife Beach, Port Elizabeth. <i<P. africanus</i> sp.nov. is also described from Cape Receife Beach. It is compared
with <i>P. tubifer</i> which it resembles but from which it can be differentiated by length of the buccal cavity,
amphid size and the shape of the spicules. <i>Eontolaimus capensis</i> gen.nov., sp.nov. is described, also from the
same sandy beach. This new genus is related to <i>Deontolaimus papillatus</i> de Man, 1880 from which it can be
distinguished, among other things, by the absence of a tooth-like structure in the buccal cavity and the presence of pre-anal tubuli.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Leptolaimidae; Nematoda [Nematodes].
Ano: 1988
URL: http://www.vliz.be/imisdocs/publications/276167.pdf
Meiobenthos of the central Arctic Ocean with special emphasis on the nematode community structure
Provedor de dados: 27
Autores: Vanreusel, A.; Clough, L.M.; Jacobsen, K.; Ambrose, W.; Jivaluk, J.; Ryheul, V.; Herman, R.; Vincx, M.
We investigated the abundance of the meiobenthos and the biomass and community structure of the nematodes in the central
Arctic Ocean along two separate transects during 1991 and 1994. Meiobenthos abundances ranged from < 100 to 600
individuals per 10 cm², in the same order of magnitude as in other oligotrophic areas of the world's deep ocean. Nematodes were
the numerically dominant meiofaunal group at every station. Nematode biomass ranged from < 1 to 48 µg dry weight per 10
cm². A combination of water depth and latitude explained 55% of the variability among stations in nematode biomass and 67% of
the variability of total abundance, implying that both vertical and advective fluxes are important sources of food to the meiofaunal
communities. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Community composition; Marine invertebrates; Meiobenthos; Spatial variations; Zoobenthos; Monhystera;
Nematoda [Nematodes]; Pitcairn I.
Ano: 2000
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7425
Nematode communities of Lake Tana and other inland water bodies of Ethiopia
Provedor de dados: 27
Autores: Abebe, E.; Mees, J.; Coomans, A.
Free-living nematodes from littoral benthie sediments of four lakes, two rivers and a hot spring in Ethiopia are studied.
Populations of nematodes encountered are identified to the species level. The general nematode (generic and species) composition
of the lakes, rivers and hot spring are appraised by giving special emphasis to the nematodes from L. Tana, i.e. three sites where
different environmental factors come into play were considered. Gelda is a site close to a river inlet (River Gelda), Gedero is a site
exposed to strong wind action while Zegie is a secluded site protected by a land mass from any strong wind action. Nematode
communities were identified using classification and ordination techniques. The identified communities are then characterised...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nematoda [Nematodes].
Ano: 2001
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=22965
Nematodes as indicators pollution: a case study from the Swartkops River system, South Africa
Provedor de dados: 27
Autores: Gyedu-Ababio, T.; Furstenberg, J.P.; Baird, D.J.; Vanreusel, A.
Nematodes from the sediments of the Swartkops estuary in Port Elizabeth, South Africa were investigated at 10 selected sites
along a salinity gradient in the subtidal region at neap tide. The relation between nematode density, genera, community structure
and environmental parameters including concentrations of seven heavy metals, Mn, Ti, Cr, Pb, Fe, Sn and Zn in the sediment were
investigated. The nematode community structure was significantly influenced by the chlorophyll a concentration and sediment
particle-size distribution. The number of genera had significant negative correlation with chlorophyll a and two heavy metals, Fe
and Zn in the sediment. The habitat preferences of the genera were also assessed. A combination of the Shannon-Wiener
Diversity...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Check lists; Density; Diversity; Ecology; Meiobenthos; Pollution; Sediment; Sediments; Nematoda
[Nematodes].
Ano: 1999
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7328
Nieuwe bijdrage tot de kennis der vrijlevende nematoden van België
Provedor de dados: 27
Autores: De Coninck, L.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nematoda [Nematodes]; Belgium.
Ano: 1932
URL: http://www.vliz.be/imisdocs/publications/294571.pdf
Selective attraction of marine bacterivorous nematodes to their bacterial food
Provedor de dados: 27
Autores: Moens, T.; Verbeeck, L.; de Mayer, A.; Swings, J.; Vincx, M.
This paper explores the role of selective attraction to food in determining the spatial (micro)distribution of closely related
nematode species. The attractiveness of 3 different bacterial strains to 4 species of Monhysteridae, <i>Diplolaimelloides
meyli, Diplolaimella dievengatensis, Monhystera</i> sp. and <i>Geomonhystera disjuncta</i>, was studied in a
multiple choice design. In our study area, the 4 nematode species considered are associated with <i>Spartina
anglica</i> detritus decay and have partially overlapping microhabitat preferences. As they all belong to the same feeding
guild, they are potential competitors for food. Each of the 4 nematode species was attracted to the bacterial strain B1, but
important...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chemotaxis; Recruitment; Taxis; Bacteria; Diplolaimella dievengatensis; Diplolaimelloides meyli;
Geomonhystera disjuncta; Nematoda [Nematodes]; Spartina anglica [common cord-grass].
Ano: 1999
URL: http://www.vliz.be/imisdocs/publications/273317.pdf
Studies of the life-history and energetics of marine and brackish-water nematodes: 2. Production,
respiration and food uptake by <i>Monhystera disjuncta</i>
Provedor de dados: 27
Autores: Herman, P.M.J.; Vranken, G.
An energy budget was constructed for the marine nematode <i>Monhystera disjuncta</i>. Respiration was measured
with a modified Cartesian diver technique, in which the nematodes were kept in agar inside the diver 'head'. The relationship
between respiration and body weight was: R=1.53 W<sup>0.75</sup>. Body growth was exponential during the
juvenile phase, with a growth rate equal to 0.61 d<sup>-1</sup>. After maturation the growth rate fell to 0,17
d<sup>-1</sup>. Food uptake was measured in experiments with radiolabeled bacteria. In one series of experiments
the accumulation of radiolabel in the nematodes was followed. In a second series the decrease in labeling was followed when
pre-labeled nematodes fed on...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bioenergetics; Brackishwater environment; Energy budget; Energy flow; Feeding; Life history; Meiobenthos;
Respiration; Monhystera disjuncta; Nematoda [Nematodes].
Ano: 1988
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3146
Sur quelques espèces nouvelles de Nématodes libres (Ceramonematinae Cobb, 1933), avec quelques
remarques de systématique
Provedor de dados: 27
Autores: De Coninck, L.A.P.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ceramonematinae; Nematoda [Nematodes].
Ano: 1942
URL: http://www.vliz.be/imisdocs/publications/291552.pdf
Temperature and salinity constraints on the life cycle of two brackish-water nematode species
Provedor de dados: 27
Autores: Moens, T.; Vincx, M.
The present study investigates the influence of salinity and temperature on the life history of two estuarine bacterivorous
nematode species, <i>Pellioditis marina</i> and <i>Diplolaimelloides meyli</i>, isolated from the
mesohaline zone of the Westerschelde Estuary, SW Netherlands. Gravid females and adult males were inoculated in petri dishes
containing agar layers of nine (for <i>P. marina</i>) or five (for <i>D. meyli</i>) different salinities, from
almost freshwater to higher than marine, and incubated at a temperature of 20°C, to study the impact of salinity; agar layers with a
salinity of 20‰, incubated under each of six different temperatures from 5 to 30°C, served to study the effect of temperature....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nematoda [Nematodes].
Ano: 2000
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7421
Temperature, salinity and food thresholds in two brackish-water bacterivorous nematode species:
assessing niches from food absorption and respiration experiments
Provedor de dados: 27
Autores: Moens, T.; Vincx, M.
Respiration and food assimilation of two estuarine bacterivorous nematodes, the rhabditid <i>Pellioditis marina</i>
and the monhysterid <i>Diplolaimelloides meyli</i>, were measured at a range of temperatures, salinities, and food
densities. The aim of this study was to identify the fundamental niche of both species in their natural habitat, and to investigate the
relative importance of food and abiotic factors in determining presence and success of nematode species in the highly dynamic
estuarine tidal environments of macrophyte detrital habitats. Of the three factors studied, salinity least impacted <i>P.
marina</i> and <i>D. meyli</i>. Respiration and assimilation in both species showed only minor...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nematoda [Nematodes].
Ano: 2000
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7422
The ecology of marine nematodes
Provedor de dados: 27
Autores: Heip, C.H.R.; Vincx, M.; Vranken, G.
Nematodes are probably the most abundant metazoans in the biosphere and of very great importance to man. As parasites of man
they are responsible for disease in hundreds of millions of people and an estimated eight billion nematodes are enjoying food,
warmth and shelter in human intestines today; <i>Ascaris lumbricoides</i> is, after the viruses responsible for
diarrhoeal disease, the second most infectious organism in the world, about a quarter of the world's population being infected
(Ash, Crompton & Keymer, 1984). Plant-parasitic nematodes cause considerable damage to crops and many species are
vectors of soil-borne viruses. Today, plant nematology is one of the most vital fields in agricultural research and is studied in
many university...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecology; Literature reviews; Nematoda [Nematodes].
Ano: 1985
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3205
The meiofauna: macrofauna ratio across the continental slope of the Goban Spur (north-east Atlantic)
Provedor de dados: 27
Autores: Flach, E.; Vanaverbeke, J.; Heip, C.H.R.
Meio- and macrofauna density and biomass were estimated at the OMEX-transect across the continental slope of the Goban Spur
at water depths ranging from 208 to 4460 m in the north-east Atlantic. A linear increase in the ratio between meio- and
macrofauna densities with increasing water depth was found. At the continental shelf meiofauna densities were similar to 50 times
higher than macrofauna densities, whereas in the abyss meiofauna densities were more than 1000 times higher. This change in
ratio was due to a significant decrease in macrofauna densities with increasing water depth, whereas the meiofauna densities
staved more or less at the same level. The ratio in biomass between meio- and macrofauna showed a dip at similar to 1000 m. At
this depth...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecology; Sediment; Sites; Spectra; Nematoda [Nematodes].
Ano: 1999
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7325
The productivity of marine nematodes
Provedor de dados: 27
Autores: Vranken, G.; Heip, C.H.R.
The productivity of marine nematodes was studied from laboratory experiments investigating the relationship between minimum
generation time and temperature, the daily birth rate as calculated from life-tables taking fecundity and survivorship into account
and the temperature regime in the field. The life cycle of <i>Monhystera disjuncta</i> is described. Females produce
about 200 eggs in agnotobiotic conditions over about 70 days: this represents 17 times their own body weight. The mean
generation time is 20 days at 12°C and this species can produce 23 generations in the field each year. The maximum annual P/B is
equal to 69. The annual P/B calculated from birth rate is 60. From similar studies on five other nematode species it is concluded...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Productivity; Productivity; Productivity; Secondary production; Nematoda [Nematodes].
Ano: 1986
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=16902
The systematics and ecology of free-living marine nematodes
Provedor de dados: 27
Autores: Heip, C.H.R.; Vincx, M.; Smol, N.; Vranken, G.
Nematodes are the most abundant metazoans in marine (littoral, estuarine, coastal and oceanic) sediments, extending from the
high-water mark into the deepest oceanic trenches (Nicholas, 1975). All marine free-living nematodes are considered to be
members of the meiobenthos; small organisms, mainly metazoans, which are separated from the larger macrobenthos either on a
methodological basis (i.e. as all animals passing a 1 mm or a 0.5 mm sieve) or a taxonomic basis (i.e. particular animal groups
such as Nematoda, Harpacticoida, Gastrotricha, Kinorhyncha, Tardigrada, Foraminifera etc. which consist exclusively or mainly
of small species living in sediments). In most circumstances, nematodes are numerically the dominant group of the meiofauna. In
fact, they...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecology; Systematics; Taxonomy; Nematoda [Nematodes].
Ano: 1982
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3417
Tidal migration of nematodes on an estuarine tidal flat (the Molenplaat, Schelde Estuary, SW
Netherlands)
Provedor de dados: 27
Autores: Steyaert, M.; Herman, P.M.J.; Moens, T.; Widdows, J.; Vincx, M.
The vertical distribution patterns of the nematode community and of the 10 most dominant nematode species on an intertidal flat
in the Schelde Estuary (the Molenplaat, The Netherlands) are described at specific time intervals over a tidal cycle. The observed
distribution profiles indicate that vertical migrations occur and are species-specific. The predatory <i>Enoploides
longispiculosus</i> and the deposit-feeding <i>Daptonema normandicum</i> migrated upwards at incoming
tide and downwards when the flat became exposed, while another deposit feeder,<i>Daptonema setosum</i>, did the
opposite. Several abiotic and biotic factors may contribute to the observed patterns. Hydrodynamics, pore water drainage and
episodic steep...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Current velocity; Marine invertebrates; Rainfall; Suspended particulate matter; Tidal effects; Vertical
distribution; Enoploides longispiculosus; Hypodontolaimus trichophora; Nematoda [Nematodes].
Ano: 2001
URL: http://www.vliz.be/imisdocs/publications/99105.pdf
Toxicity of copper, mercury and lead to a marine nematode
Provedor de dados: 27
Autores: Vranken, G.; Heip, C.H.R.
Toxicity of copper, lead and mercury to the nematode <i>Diplolaimella</i> spec 1 is studied. Mortality responses
obtained demonstrate high resistance to heavy metals. Population growth parameters as the intrinsic rate of natural increase and
net-reproductivity are significantly depressed at copper-concentrations which cause no juvenile mortality. The lowest
concentrations tested caused significant inhibition of development rate in both sexes. For this particular nematode species
suppression of fecundity and developmental inhibition are more reliable criteria, determining non-exceedable limits with regard to
environmental safety. Our tests show that nematode productivity may be significantly depressed at copper levels found in some
areas of the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Copper; Lead; Mercury; Toxicity; Nematoda [Nematodes].
Ano: 1986
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3250
Two new species of <i>Morlaixia</i> gen. n. (Nematoda, Diplopeltidae) with a
subterminal ventral mouth
Provedor de dados: 27
Autores: Vincx, M.; Gourbault, N.
A new genus of the Diplopeltidae, <i>Morlaixia</i> gen, n., is described; species are characterized by an
asymmetrical anterior end, which is caused by the subventral position of the mouth opening and the buccal cavity; that feature is
unique for the group. Two new species, <i>M , contusa</i> sp. n. and <i>M. obscura</i> sp. n., are
described from fine sands and silty sediments in the Bay of Morlaix.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: New genera; New species; Morlaixia; Nematoda [Nematodes].
Ano: 1988
URL: http://www.vliz.be/imisdocs/publications/228048.pdf