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This final contribution to the International Helgoland Symposium 1976 summarizes important information presented during the meeting, discusses some concepts and principles of ecosystem research, draws a few co...
The development of North Sea coastal plankton communities in four simultaneously filled plastic bags was followed for one month. To obtain a concentration of 5 ppb in the water phase a single dose of mercuric ...
Variations in abundance and species composition of macro-zoobenthos were studied at a sublittoral muddy-bottom station in the inner part of the German Bight from 1969 to 1976. The fauna of this area can be inc...
Except for the special cases of upwelled water and the spring blooms in temperate and boreal waters, the productivity of the oceans is largely governed by the rate of nutrient regeneration in surface waters. T...
Cool nutrient rich waters combined with a rocky coastline extending infratidally make the west coast of South Africa well suited to growth of kelp species. The kelp bed community is compared with the main kelp...
IntensiveStrongylocentrotus droebachiensis grazing of a previously sampled one-hectare plot provided an opportunity for quantitatively investigating grazing impact on the benthic macrophyte community and communit...
The state of knowledge of marine and estuarine sublittoral benthic synecology may be said to be still in a descriptive stage of study. Much of the recent literature of the subject concerns either qualitative a...
Physicists have two conceptions of the stability of systems: global and neighbourhood stability. Global stability corresponds to the idea of successional changes leading to climax communities. Yet, neighbourho...
In the first detailed ecological description of a fringing reef (Mergner & Schuhmacher, 1974) two parts of the reefs south of Aqaba (Red Sea) were considered. These investigations have been extended to an eco-...
The major faunistic and floristic components occupying space on the coral reefs of the northern Gulf of Eilat (Red Sea) are stony corals, soft corals and benthic algae. The percent living coverage of the three...
The northernmost mangrove forests of the Red Sea are described. Temperature and salinity conditions were found to be extreme, obviously reducing the diversity of the ecosystem and presumably setting the geogra...
Composition and distribution of intertidal ecosystem of rocky and unconsolidated facies were quantitatively studied from 1951 to 1975 in about 40 regions of the White, Barents, Bering, Okchotsk and Japan Seas....
Production and recovery of ammonia-N was studied in the second and third trophic levels of a mariculture system on St. Croix, US Virgin Islands. The diatomChaetoceros curvisetus, grown on nutrients in artificiall...
The study is based on data (n=244) from light-saturation experiments utilizing artificial incubation under fluorescent light. Values of maximum photosynthetic rate,P max, and the light intensity at which it takes...
Twelve replicate 150-l laboratory microcosms were developed using whole water samples and natural benthic communities from Narragansett Bay, Rhode Island (USA). The microcosms were scaled to the bay in terms o...
In the ascophoran bryozoanCryptosula pallasiana (Moll) many examples of regenerative growth and of “abnormal” zooids have been observed. Most of the different forms of “monsters” are caused by fusion of zooids or...
Six different types of test substrates, arranged in order of texture from smooth (Solnhofen limestone, Bunter sandstone, and basalt) to rough surfaces (Middle Triassic limestone, granite, and basaltic lava), w...
Hg concentrations in benthic invertebrates of the Elbe estuary were analyzed by atomic absorption spectrophotometry and instrumental neutron activation analysis. In general Hg levels in organisms decreased fro...
Praeoral tentacles and epidermis of the anterior body region ofBranchiostoma lanceolatum Pallas have been investigated by electron microscopy. The epidermis of the praeoral tentacles and the anterior body region ...
A total of 90, weekly exploited populations of the harpacticoid copepodTisbe holothuriae Humes were exposed to 148, 222, 333, 500, 750 or 1125µg Cd++ l−1, combined with exploitation rates of 10, 30, 50, 70 or 90%...
The larval development is discussed and calyptopis stages I–III as well as furcilia stages I–VII are described. The larval development is similar to that ofE. spinifera, E. longirostris andE. triacantha (group d ...
Alaria esculenta (L.) Grev. sporophytes, raised in culture and originating from the North of Iceland were immersed in the sea near Helgoland (North Sea) for the period from February to August. Notable growth of ...
The growth rate of germlings of threeFucus species (F. distichus subsp.edentatus from Iceland,F. vesiculosus from Helgoland, North Sea, andF. virsoides from the North Adriatic Sea) has been investigated under dif...
This paper concentrates on the study of vegetative development and sexual reproduction inLagenisma coscinodisci Drebes. Before infecting a diatom cell (Coscinodiscus granii), the freshly released zoospores pass t...
This report represents a photographic documentation of the more conspicuous species of the marine algal vegetation of the island Helgoland (North Sea), based on collections and observations made since 1959. Th...
In Versuchen zur Aufnahme verschiedener Aminosäuren durch die Körperoberfläche bei dem OligochaetenEnchytraeus albidus und dem PolychaetenNereis diversicolor betrug die Absorptionsrate von14C-L-Arginin aus einer ...
Im Rahmen eines Aquakulturvorhabens wurde geprüft, inwieweit sich die Gegenwart der DiatomeePhaeodactylum tricornutum auf die Zucht der GarneleMacrobrachium rosenbergii (de Man) auswirkt. Als Nahrung für die Larv...
Observations on invertebrates living in or on Scyphomedusae are compiled from literature. 51 species of 28 genera are listed as hosts for different taxa (Actiniariae, Turbellaria, Trematoda, Cestoda, Nematoda,...
Mean length, width and shape of the fecal pellets of the four planktonic copepod species,Acartia bifilosa, Centropages hamatus, Oithona similis andPseudocalanus elongatus, were studied. Mean volumes of the fecal ...
La production primaire d'une station située sur le récif frangeant de Moorea (îles de la Société, Polynésie Française) est déduite des variations nycthémérales des teneurs en oxygène dissous de l'eau de mer, a...
The sessile, filter-feeding tube wormPomatoceros triqueter (L.), which occurs on solid substrata such as rocks or shells, is eurybathic in Helgoland waters (southern North Sea). The paper presents data from 1970 ...
Six different types of test substrates were exposed in the tidal zone of the wadden sea near the harbour of List (Island of Sylt, North Sea): Solnhofen limestone, Middle Triassic limestone, Bunter sandstone, g...
At various coastal positions of the western Mediterranean starfishes of the genusAstropecten were recorded. The largest of the six species,A. aranciacus, proved to be a generalist in occurrence; however, its abun...
Oocyte development ofLepidochitona cinereus L. has been examined by electron microscope with special regard to ultrastructural changes during vitellogenesis. Oogenesis can be subdivided into five stages based on ...
Während der Fortpflanzungszeit im arktischen Sommer erzeugen die ♀♀ vonA. spetsbergensis Carlgren Oocyten, die durch ihre Hülle aus umfangreicher Mesogloea und histologisch stark verändertem Ovarial-Endoderm auff...
This study investigates the taxonomic status of a Helgoland species hitherto regarded asBryopsis plumosa (Huds.)Ag. The habitus of the plant concerned agrees well with that of the original specimens ofBryopsis ly...
During a cruise with R. V. “Alkor” from Kiel Bight to Finnish Bay, nearly 100 seston samples were taken during April/May 1973. Samples from the 23 stations were analyzed for lead, cadmium, copper, iron and zin...
The structure of the smooth tentacles inLanice conchilega Pallas was studied employing an electron microscope. The monolayered tentacle epithelium is covered by a zonated cuticle which bears a granular border. Sp...
Wenn Nauplien des SalinenkrebsesArtemia salina Zoëa-Stadien vonRhithropanopeus harrisii undNeopanope als Nahrung geboten werden, vollzieht sich die Metamorphose zum Megalopa-Stadium bei einem wesentlich größeren ...
In shallow water off the north coast of Sardinia (western Mediterranean) the frequency of occurrence of the starfishAstropecten aranciacus was recorded in 70 sample areas of 25 m2 each. Four environmental factors...
Six different types of test substrates were exposed in the tidal zone of the wadden sea near the harbour of List (island of Sylt, North Sea): chalk of Solnhofen, limestone, mottled sandstone, granite, basalt a...
Es wurde bisher angenommen, das äußerst wichtige FischnährtierDiastylis rathkei Kröyer habe eine besonders hohe Bedeutung innerhalb der bodennahen Fauna, dem Hyperbenthos. Mit Hilfe des Unterwasserlaboratoriums (...
In weekly exploited populations of the harpacticoid copepodTisbe holothuriae Humes, effects of exploitation rate on production of eggs, embryos, nauplii and adults, as well as frequency of egg-sac formation, rate...
Die Nahrungsausnutzung des herbivoren FischesTilapia mossambica wurde bei unterschiedlichem Futterangebot untersucht. Als Nahrung dienten die GrünalgeSpirogyra maxima, Ziegenleber und lebende Kaulquappen. Mit Alg...
The investigations conducted provide a detailed picture of the colonization pattern of meiofauna on various sediments in the western Baltic Sea. Each sample core had an area of 10 cm2
The annual cycle and distribution of the benthic copepod fauna of a shallow inshore area in the South of Kiel Bay (Baltic Sea) were investigated. The species composition found is not typical for medium fine sa...
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