bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feeding Mechanisms and Comparative Functional Morphology of Macrothricidae (Crustacea : Cladocera)
Authors: Sergeev V. N. 
Published: February 2007

AbstractFeeding of the Macrothricidae is accomplished b y two principal methods: active collection of food from the substrate surface and filtration of suspended particles. As differentiated from Ilyocryptus sordidus and Lathonura rectirostris, Ophryoxus gracilis is equipped with the most universal set of limbs allowing catching of food along with filtratory feeding. They are described in detail.Lathonura rectirostris is a highly specialized species, an inhabitant of plant thickets, since i t adapted to feeding on epiphytic algae and particles at the plant surface. Feeding is accomplished only by scraping or catching food by means of complexes of setae of the II pair of limbs. Filtratory feeding and appropriate structures are lacking.The structure and action of the limb apparatus of Ilyocryptus sordidus rule out active catching of food particles.
Decomposition of Dissolved Carbohydrates Derived from Diatoms of Lake Yuno‐ko
Authors: Ogura Norio , Gotoh Tadashi 
Published: February 2007

AbstractThe aerobic decomposition of freshwater phytoplankton was monitored over a 10 day period to determine rates of production and microbial utilization of total dissolved organic carbon and dissolved carbohydrates. Following molecular weight fractionation of the total dissolved organic and carbohydrate carbon produced, it was found that each component contained a highly labile as well as a partially refractory fraction. Specific decomposition rate constants were determined for both fractions. Molecular weight retention characteristics of the ultrafilter used were also evaluated.
Food of White Catfish, Ictalurus catus (LINN.) (Ictaluridae) Stocked in Farm Ponds
Authors: Devaraj K. V. 
Published: February 2007

AbstractStomach contents of 124 white catfish, Ictalurus catus, ranging from 51 to 431 mm collected from farm ponds of Auburn University, Auburn, Alabama were examined. Fishes in these ponds were given supplemental feed six days a week. Juvenile catfish below 100 mm fed more actively on a variety of food items than larger fish. White catfish measuring 201 mm and above preferred dipterans to other natural food items. In all size groups supplemental feed occupied a dominant position when compared to other food items. Other food items present in the stomachs in varying quantities included detritus, micro‐crustaceans, trichopterans, fish remains and miscellaneous items, thus indicating the omnivorous feeding of white catfish.
The Effects of Hydrostatic Pressure on Living Aquatic Organisms II. Pressure Chambers, Apparatus and Experimental Methods Used in the Florida State University Hyperbaric Ecology Program (1970–73)
Authors: Menzies Robert J. , George Robert Y. , Avent Robert M. 
Published: February 2007

AbstractThe methods and pressure chambers used in the experiments are described. Special attention is paid to standardization of results, to problems of operation, adiabatic heating, safety procedures, and philosophy of operation of the pressure systems in the exploration of the problem.
The Effects of Hydrostatic Pressure on Living Aquatic Organisms VIII. Behavioral and Metabolic Responses of Uca pugilator to Variations in Hydrostatic Pressure and Temperature
Authors: Avent Robert M. 
Published: February 2007

AbstractIn systematic examination of the pressure responses of a broad spectrum of organic life, it is very important to know the range of variation exhibited by a single species. As a consequence of extensive observations on the effects of pressure and temperature on behavioral responses, lethality, and metabolic responses, it is clear that the range of variation in pressure required to induce a response diminishes as the species taxon is approached. The rate of exposure to pressure does not influence the pressure required for reversible behavioral responses. In contrast, the duration of pressure dramatically influences the pressure required to achieve death with the shorter time periods requiring much higher pressure levels than the longer time periods. Notwithstanding this relationship there appears some evidence suggesting that short term acclimation to pressure does occur.
Electron Microscope Observations on the Fine Structure of the Chloroplasts of Algae. II. The Chloroplasts of Caulerpa (Chlorophyceae)
Authors: Hori Terumitsu 
Published: February 2007

AbstractThe plastid ultrastructure of 12 species of Caulerpa (Chlorophyceae) was investigated by the electron microscope. A simpler pyrenoid structure was demonstrated in one species. The conspicuous concentric lamellar bodies, which are characteristic of algae with heteroplasty, were present both in the chloroplasts and the amyloplasts of all the species examined. The possible function and taxonomical value of the bodies were discussed.
Der Vitaminbedarf der Regenbogenforelle (Salmo gairdneri)
Authors: Steffens Werner 
Published: February 2007

The Vitamin Requirements of Rainbow Trout (Salmo gairdneri)A sufficient supply of vitamins is of major importance in Salmonidae feeding. Therefore considerable amounts of vitamins must be added to complete mixed feed for rainbow trout. The author gives a survey of the function of the various vitamins in the organism and describes the vitamin deficiency symptoms found on Salmonidae, especially on rainbow trout. Finally, recommendations are given for the vitaminization of mixed feed for rainbow trout.
Die Korallenriffe Kubas III. Riegelriff und Korallenterrasse, zwei verwandte Erscheinungen des Bankriffes
Authors: Kühlmann Dietrich H. H. 
Published: February 2007

The Coral Reefs of Cuba. III. Cross‐bar Reef and Coral Terrace, Two Related Phenomenona of the Bank Reef Los arrecifes de corales de Cuba. III. Arrecife de tranca y terraza de corales, dos fenomenos parientes del arrecife bancoAqualungs were used for the study of the coral reefs of Cuba, about which comparatively little has been known so far. Their small dimensions and their position close to the coastline or in the central part of the island plateau, instead of along the shelf edge, can be attributed to the inhibiting and delaying influence of glacial periods. The different types of reefs and other coral habitats originated as a result of geological, hydrological and biological factors, while the formation of coral associations was dependent on the prevailing physical and chemical features of the environment. The following is a description of the cross‐bar reef and the coral terrace, two coral habitats. The present work continues earlier articles related to the subject and published in this periodical.
Limnological Features of a Tropical Impoundment, Bhavanisagar Reservoir (Tamil Nadu), India
Authors: Sreenivasan A. 
Published: February 2007

AbstractIn the Bhavanisagar Reservoir a stable thermal stratification did not occur, but the thermal stability was fairly high. Oxygen deficits occurred frequently as well as complete anoxic conditions. Influx of flood waters improved the bottom oxygen conditions. This together with other factors indicates a high level of metabolic activity and productivity. Primary production rates were fairly high. There has been a change in fish population; some introduced species (like Catla and Labeo calbasu) have increased in the catches. It is felt that more fish could be exploited from this reservoir.
Accumulation of Natural Radionuclides in the Bottom Sediments and by Aquatic Organisms of Streams
Authors: Justýn Jaromír , Stanêk Zdenêk 
Published: February 2007

AbstractThe accumulation of natural radioisotopes by aquatic organisms and bottom sediments was studied in two small rivers, one uncontaminated and the other polluted by effluents of uranium ore mining and milling.Parabolic regressions between the water and uppermost sediment content of both uranium and total beta activity (corrected for 40K content) is presented and demonstrates the water cumulative capacity of organically rich sediments. For 226Ra no significant differences between sediments with different organic content were found. The 226Ra content of bottom sediments is expressed as a power function of radium and calcium concentration in the water.In the given reaches, 53% and 85% of uranium and over 90% of 226Ra and total beta activity (corrected for 40K) was accumulated in the upper two centimetres of sediments and biomass of aquatic vegetation. Filamentous algae, plankton, aquatic bryophyta and macrophyta from the present and other published data showed rather higher cumulation capacities as compared with bottom sediments.
Seasonal Development of Phytoplankton in Fish Ponds
Authors: Fott Jan , Kořínek Vladimír , Pražáková Miroslava , Vondruš Bohumil , Forejt Karel 
Published: February 2007

AbstractAt the fish ponds under study the authors defined several types of plankton which have been frequently found during the season (April – October). These types are: Early‐spring maximum of phytoplankton, Depression of phytoplankton, Bloom of Aphanizomenon, Maximum of Chlorococcales.The periods of “depression” seem to be typical for the managed carp ponds in the spring. They are characterized by the low density of rapidly reproducing algal populations (e. g. Cryptomonas) and by the dense populations of large cladocerans of the genus Daphnia. Chlorophyll in phytoplankton is less than 5μg/l, transparency is higher than 2 meters.Periods of the spring depression may be followed by the maxima of either Aphanizomenon or Chlorococcales, with concentrations of chlorophyll increasing to 100 μg/l and more. The change from the phase of “depression” to the “maximum of Chlorococcales” is accompanied by decrease in numbers of Daphnia and increase in numbers of the small cladoceran species, but all the mechanisms responsible for the transition are not yet fully understood.
Untersuchungen zum Phosphatmetabolismus einer Trinkwassertalsperre
Authors: Hofmann Reiner 
Published: February 2007

AbstractThe examinations showed that the phosphate supply for the planktonic primary production comes almost exclusively from the influxes. The nutrient pool in the hypolimnion and in the sediment does not play a leading part. Evidently, that is often so in reservoirs.Both the phytoplankton (the most frequent species are Asterionella formosa and Fragilaria crotonensis) and the concentration of phosphate fractions are subject to considerable seasonal variations. The Asterionella spring maximum, typical of this reservoir, is released directly or indirectly by meteorological factors. An adequate orthophosphate concentration is a basic condition which is accomplished, however, nearly every year. The autumnal Fragilaria maximum begins when a definite mixing depth hae been achieved. The breakdown of a diatom maximum is caused almost at all times by exhaustion of the phosphate reserves.
Notes on the influence of particulate organic matter (POM) on light conditions at a coral reef of the Australian great barrier reef
Authors: H. H. Kühlmann Dietrich 
Published: February 2007

AbstractOn the outer slope of a coral reef in the Great Barrier Reef, at a depth of 11‐12 in without artificial light, bright red and rose colours were observed to occur on coelenterates, because masses of floating luminescent bacteria in the environment.
Catalogue of the Microplankton in the gulf of marseilles
Authors: Travers Anne , Travers Marc 
Published: February 2007

AbstractA large number of microplankton samples has been collected during every season in the Gulf of Marseilles from 1960 to 1968 (water samples and net tows). The authors have examined them with ecological, quantitative and qualitative purposes. Only the last one is considered here. About seven hundred systematic units have been identified. The most diverse taxonomical, groups are the diatoms and dinoflagellates, which exhibit much more numerous taxa than tintinnids, coccolithophorids and silicoflagellates.
Littoral Benthos of the Northern Baltic Sea. III. Macrobenthos of the Hydrolittoral Belt of Filamentous Algae on rocky shores in Tvärminne
Authors: Hällfors Guy , Kangas Pentti , Lappalainen Annikki 
Published: February 2007

AbstractThe community composition was studied quantitatively in two localities in 1968‐1970. The average ash‐free dry weights of the plants in a fully exposed and a moderately exposed locality were 48.6 g. m−2 and 93.3 g. m−2, respectively. The average animal ash‐free dry weights were 2.52 g. m−2 and 3.45 g. m−2. and the average numbers of animal individuals were 5360 m−2 and 15450. m−2.The communities are characterized by the strong dominance of a few species. viz. Cladophora glomerata. Gammarus spp. and Chironomid larvae. The species diversity is thus very low. The seasonal aspects of species composition and abundance are presented. and some factors causing the differences between the localities are discussed.
Untersuchungen über das Phytoplankton und einige Umweltparameter des Shatt al‐Arab (Irak)
Authors: Kell Volkbert , A. H. Saad Massoud 
Published: February 2007

AbstractSamples of phytoplankton were taken from the Euphrat and Tigris Estuary (Shatt al‐Arab) in April 1974 and investigated by means of the inverted microscope. Among 226 species identified in the samples 95 were of marine origin. The share of diatoms in the total numbers of cells from all stations amounted to 68%. The abundance of planktonic green algae amounted to 19%, of the blue greens to 13%. The number of marine species continuously increased in the longitudinal axis of the 139 km section considered. The data of the phytoplankton were compared with the gradation of some environmental variables (temperature, transparency, dissolved oxygen, chloride). Regular longitudinal or vertical differences of these parameters were not observed.
Food consumption and utilization in two freshwater cyclopoid copepods (mesocyclops edax and cyclops vicinus)
Authors: Brandl ZdenêK , Fernando C. H. 
Published: February 2007

AbstractThe predatory feeding of Mesocyclops edax and Cyclops vicinus was studied using the 14C‐labelled Ceriodaphnia and some other kinds of the crustacean zooplankters. When given a choice, both species exhibited clear selection of smaller specimens of prey. The feeding rates depend on the kind of prey. The daily ration for the prey readily accepted by Mesocyclops was roughly equal to the predator's biomass, while it was only one half or one third of the body biomass in Cyclops vicinus. Only about one third of the killed biomass was actually ingested and 21–32% was assimilated when the copepods preyed upon the cladocerans or the copepodid larvae. When fed with naupliar larvae the cyclopoid copepods assimilated over 70% of the killed biomass. Almost one half of the freshly assimilated carbon passes through the short term cycle and is quickly respired and excreted.
Community patterns on a submerged barrier reef at Barbados, West Indies
Authors: Ott Bruce 
Published: February 2007

AbstractA quantitative survey of a submerged barrier reef was undertaken in Barbados, West Indies, over a two year period (1971–73). Photo‐line transects were employed to obtain coverage data on corals and other benthic organisms. Light, sedimentation, currents, oxygen, temperature and salinity were also monitored.Results indicate corals cover about 30 per cent of the bottom with living colonies; another 7 per cent is contributed by other zoobenthos. The most abundant coral species are Montastrea annularis, M. cavernosa and Siderastrea siderea, each contributing between 4 and 5 per cent of bottom cover. Light is the only physical factor monitored that correlated significantly with biomass; sedimentation may have a secondary effect. Most of the barrier reef is composed of mixed coral associations forming a biologically accommodated community.Comparisons are made between the barrier reef in Barbados and deeper reefs in Jamaica and Curacao. Reefs are, in the main, similar but coral species and community structure differences do occur.
Faunistisch‐ökologische Untersuchungen am Meiobenthos des Saaler Boddens (Darßer Boddenkette), Ostsee
Authors: Beschnidt Jochen , Noack Bodo 
Published: February 2007

AbstractThe meiofauna of the Saaler Bodden was investigated in the period from September 1969 to April 1970. The Saaler Bodden is that part of a brackish water area which is situated farthest from the Baltic Sea. In the southern part we usually find fresh water; in the northern part, the salinity rises to a maximum of 5 to 6‰. The authors give a short review of the hydrographical and biological peculiarities of the Saaler Bodden followed by remarks as to the qualitative and quantitative distribution of the meiofauna. Abundance and biomass are determined for Nematoda, Oligochaeta, Ostracoda, Copepoda, Harpacticoidea, Halacarida and Chironomid larvae. Oligochaeta and Ostracoda are dealt with in detail. The ecological requirements of the different species are discussed in this connection and their role in the balance of matter of this water body is pointed out.
Complete Carbon and Nitrogen Budgets for the Carnivorous Amphipod, Calliopius laeviusculus (KRØYER)
Authors: Dagg Michael J. 
Published: February 2007

AbstractThe marine amphipod Calliopius laeviusculus was grown in the laboratory under maximum food levels at 8°C, 12°C, and 15°C. The effects of body size and temperature on all budget parameters were determined and equations describing each parameter as a function of body carbon and nitrogen content were used to construct and check the balance of the budgets. The energetics of the amphipod are discussed.
Effects of the Amount of Food on Duration of Stages, Mortality Rates, and Size of Individuals in Tropisternus lateralis nimbatus (SAY) (Coleoptera: Hydrophylidae)
Authors: Hosseinie Shidokht O. 
Published: February 2007

AbstractLarvae of Tropisternus lateralis nimbatus (SAY) were reared in the laboratory using different feeding regimes. Controls were fed as many mosquito larvae as they would readily eat until the later larval stages. Experimental groups were reared on a reduced number of larvae per day. The duration of stages, growth ratios, mortality rates, and elytral lengths in the control and experimental groups are compared.
Der Jahresgang von Neuston im Golf von Neapel
Authors: Hartmann Jürgen 
Published: February 2007

AbstractThe annual fluctuations in the occurrence of 91 taxa which were identified, made the recognition of 4 main seasonal populations possible. Trends were observed, as well as analogies to other patterns of distribution. On an average, more than half of the fauna was displaced from month to month, but the variation in the density of subtropical neuston appeared to be less over an annual period than it was during the day, and from region to region. The dominance of certain species and occurrence of neuston throughout the year demonstrated, that regionally at least a biocoenosis exists continously at the surface of the sea.
Comparative Studies on the Developmental Stages of Three Species of Tropisternus (Coleoptera: Hydrophilidae)
Authors: Hosseinie Shidokht O. 
Published: February 2007

AbstractThe egg cases, eggs, and different stages of life cycles of Tropisternus lateralis (Fabricius), T. blatchleyi D'Orchymont, and T. collaris (Fabricius) are described. A table is given for separating the various developmental stages of the three species.
Capacité photosynthétique du phytoplancton de la couche aphotique dans le fjord du Saguenay. Photosynthetic Capacity of Deep Phytoplankton in the Saguenay Fjord
Authors: Cǒte Raynald , Lacroix Guy 
Published: February 2007

AbstractAbnormally high chlorophyll values have been observed in the deep layer of the Saguenay Fjord, Québec, Canada. Experiments were conducted to assess the capability of this darkened phytoplankton to photosynthetize upon reillumination. It was found that photosynthetic capacity is well retained by deep phytoplankton of the Saguenay, as shown by relatively high production rates, a low tidal variability of these rates and very high P : B ratios.
Some Factors Affecting on Dry Weight, Organic Weight and Concentrations of Carbon and Nitrogen in Freshly Prepared and in Preserved Zooplankton
Authors: Omori Makoto 
Published: February 2007

AbstractEffects of rinsing and preservation on dry weight, organic weight, and chemical composition were determined on the chaetognath Sagitta nagae and the copepods Calanus sinicus, Pleuromamma xiphias and Acartia tonsa. Samples rinsed with distilled water were always lighter than comparable samples rinsed with seawater, showing apparent decrease in the organic matter and chemical contents (as total carbon and nitrogen) by weight; these losses increased with increasing volume of the rinse water. The volume of distilled water used for rinsing should be less than 0.3 ml per 1 mg dry weight of sample in order to avoid the significant loss of body substances. Isotonic ammonium formate rinse often resulted in the widest range of variation and on an average the organic weight and chemical contents were slightly lower than those of fresh samples rinsed with filtered seawater. Freeze‐drying samples resulted in dry and organic weights as well as chemical compositions that were somewhat greater than oven‐dried samples. The organic matter and chemical contents by weight decreased significantly within 2.5 days of being placed in Borax‐buffered formaldehyde‐sea water solution. Loss of organic weight from fresh samples exceeded 20% after one week of the preservation. Hexamine‐buffered formaldehyde solution showed a result which was different from the Borax‐buffered solution.
Facteurs limitant la production primaire des eaux oligotrophes d'une aire eôtière méditerranéenne (Calanque d'En‐Vau, Marseille). Factors Limiting the Primary Production of Oligotrophic Waters in a Mediterranean Coastal Area (Calanque d'En‐Vau, Marseilles)
Authors: Berland B. R. , Bonin D. J. , Maestrini S. Y. 
Published: February 2007

AbstractThe importance of different factors involved in the limitation of primary production in oligotrophic Mediterranean waters were investigated, through both nutrient and production estimations and algal bioassays. All the results obtained show that phosphorus is the main limiting factor of algal production. Nitrogen and chelating substances appear to be less limiting and vitamins play a small role. Light and temperature were not limiting, but higher temperatures were responsible for increased physiological activities of the phytoplankton. Previous results from the literature and those reported allow the authors to conclude that, as far as primary production is concerned, the northwestern part of the Mediterranean Sea differs from the large oceans.
Composition and Structure of Zooplankton Communities in Eighteen Arctic and Subarctic Lakes
Authors: Moore James W. 
Published: February 2007

AbstractThe factors influencing the composition and structure of zooplankton communities in 18 lakes in the Canadian arctic and subarctic were determined during 1975 and 1976. Phytoplankton were consumed in very low numbers by all species (Diaptomus sicilis, Heterocope septentrionalis, Cyclops scutifer, Daphnia longiremis, Bosmina longirostris, Holopedium gibberum, Keratella cochlearis, Kellicottia longispina) and therefore differences in algal productivity among the lakes had little effect on the zooplankton. Variations in surface area, maximum water depth, pH and the ionic composition of the water were also unimportant in controlling the communities. However, low temperature exerted strong influence over the diversity, abundance, fecundity and vertical distribution of most species.