bluuebunny/crossref_metadata_2025_split huggingface dataset:
Der frühlarvale Köcherbau von Micrasema longulum McL. (Trichoptera, Brachycentridae)
Authors: Bohle Hans Wilhelm 
Published: February 2007

Case Construction of Young Larvae of Micrasema longulum McL. (Trichoptera, Brachycentridae)The method of case building used by the first three larval instars of Micrasema longulum is described. The initial case is constructed above the hatching aperture in the jelly of the egg mass, in the same way as it is done by other species of Brachycentridae. The material of the initial case is caught from drifting particles in running water. From the end of the first larval instar only silk is used for the extension of the case. Two silken layers of a very regular pattern are to be distinguished. The construction of the cloverleaf‐shaped posterior aperture is described. Some of the methods used for the case building show a maturing process during ontogenesis.
Growth and Differentiation of Seedling of an Aquatic Plant, Trapella sinensis Oliv. I. Some Growth Characteristics in the Early Stage
Authors: Yabe Akira , Okuda Masao , Takada Hideo 
Published: February 2007

AbstractIt was shown that the early growth of Trapella sinensis seedlings can be divided into two distinct stages based upon susceptibility for different growth‐regulators, such as gibberellin, kinetin, and the extract of Chlorella cells grown in light. The two stages were observed on the 7th and the 10th days, respectively. Especially the epicotyl showed different sensitivities to the growth regulators mentioned above. The effect of gibberellin (GA3), kinetin and the extract of Chlorella cells grown in light on the growth of T. sinensis seedlings after germination at 23 °C in light at 2000 lux was investigated. Each addition was done at zero time and after 3, 6 and 10 days growth, and the effect was observed subsequent every 3 or 4 days.
Growth and Differentiation of Seedlings of an Aquatic Plant, Trapella sinensis OLIV II. Photosynthesis and Respiration of Seedling in Early Stages
Authors: Yabe Akira , Okuda Masao , Takada Hideo 
Published: February 2007

AbstractTrapella sinensis seedlings were examined to determine whether the effect of growth regulators such as gibberellin (GA3), kinetin and the extract of Chlorella cells on chlorophyll formation, photosynthetic activity and cytochrome oxidase activity depend upon the developmental stage. Each addition promoted the growth on both the basis of dry weight and of fresh weight. Among these regulators, only Chlorella extract promoted growth as a result of an activated rate of photosynthesis through increased chlorophyll formation. There also was an increased respiratory rate through increased cytochrome oxidase activity.
Einige histologische und histochemische Untersuchungen epidermaler Proliferationen bei postlarvalen Aalstadien
Authors: Bremer Heinz 
Published: February 2007

Some Histological and Histochemical Investigations on Epidermal Proliferations of Postlarval Stages of the Eel (Anguilla anguilla L.)The development of fish‐pox on the skin of post‐larval eels is described as an epithelial folding in the sense of a hyperplastic proliferation. It is supposed that this is correlated with an osmotic overburdening.
Enumeration of Bacteria in Sea Water
Authors: Lewin Ralph A. 
Published: February 2007

AbstractThe choice of methods to be used for the enumeration of bacteria in sea water must depend on the objectives of the investigators. Comparisons of data based on different methods may be invalid. An operational definition is given for a colony‐generating unit (CGU) which, under some conditions, may be a single viable bacterium. Such units can conveniently be enumerated by a modification of the “minimum probable number” method currently employed in aquatic bacteriology. Counts of “viable bacteria” (CGU) in surface sea water samples from the region of the North Pacific Gyre (28° N, 155°W) were estimated to range from 10,000 to 200,000 per litre.
A System for the Quantitative Sampling of Shallow Water Benthos
Authors: Kritzler H. , Hiskey R. M. , Thomas P. J. 
Published: February 2007

AbstractAn air lift, operated by a diver‐boatman team and permitting rapid excision and automatic sieving of uniform portions of mud, sand, and fine to medium shell hash bottoms, is described. The apparatus can be deployed from a very small boat. It is inexpensive to make and to operate and has been used with great success at depths of not more than five meters.
A Seasonal Quantitative Study of the Littoral Cladocera and Copepoda in a Bog Pond and an Acid Marsh in Newfoundland
Authors: Daggett Rollin F. , Davis Charles C. 
Published: February 2007

AbstractA quantitative study was made of the littoral microcrustaceans in a bog pond and an acid marsh located on the Avalon Peninsula, Newfoundland, from May, 1972 to May, 1973. A total of 17 species of Cladocera and 7 species of Copepoda were found in La Manche Marsh, while 21 species of Cladocera and 5 species of Copepoda were collected in Round Pond. The maximum standing stocks were similar in the two localities. The dominant forms in the summer and fall in La Manche Marsh were Cladocera: Acantholeberis curvirostris, Biapertura intermedia, Chydorus sphaericus, and Ilyocryptus spinifer. In the winter the copepod, Macrocyclops albidus, was dominant, while Cyclops varicans rubellus was the most abundant species in the spring. Round Pond also was dominated by Cladocera in the summer and fall; namely, Acroperus alonoides, Alona rustica, Alonella excisa, Chydorus sphaericus, and Sida crystallina. The copepods, Eucyclops agilis and Macrocyclops albidus, were dominant in the winter and early spring.
Benthic Invertebrates in Delaware Bay: Animal‐Sediment Associations of the Dominant Species
Authors: Kinner Peter , Maurer Don , Leathem Wayne 
Published: February 2007

AbstractThe purpose of this study was to determine the composition of the benthic fauna near the mouth of Delaware Bay. One hundred and five species were collected and identified from 277 grab samples. A sediment sample was also collected at each of the stations. Faunal density was low with the number of individuals rarely exceeding 10/0.1 m2. Species were ranked according to number of individuals; the nine top species comprised 83.4% of the fauna. The top three species, Tellina agilis, Gemma gemma, and Nucula proxima, comprised 65.2% of all the individuals collected. A high percentage of the species (41.9%) occurred in two samples or less. The six most frequently collected species were compared with six sediment classes based on weight percentage of siltclay. Protohaustorius wigleyi and Trichophoxus epistomus were found mainly in less than 10% silt‐clay. Tellina agilis and Ampelisca verrilli were transitional between the pure sand and mud facies. Nucula proxima and Heteromastus filiformis were members of a high silt‐clay facies (<50% silt‐clay). Diversity values were significantly greater (.05) in the low silt‐clay sediments (0–25% silt‐clay) than in the high silt‐clay sediments (> 25% silt‐clay). The relative dominance (redundancy) was not significantly different in any of the sediment types.
Rotorua Phytoplankton Reconsidered (North Island of New Zealand)
Authors: Thomasson Kuno 
Published: February 2007

AbstractAs early as in 1888, NORDSTEDT published some information about the algal flora of Rotorua lakes, on the North Island of New Zealand. He studied samples from the lakes Rotomahana and Tarawera, and made some notes on the algae in Lake Taupo. Since then a number of minor contributions with additional information about the algal flora of the Rotorua district have been published. The present paper describes the composition of phytoplankton in nine of the lakes in Rotorua district, and in Lake Taupo. These are all monomictic soft water lakes. The plankton is fairly rich in desmids, quantitatively as well as qualitatively. The study is based on random sampling by the author in March, 1968.
Limnological Studies of a Subarctic Lake System
Authors: Alexander Vera , Barsdate Robert J. 
Published: February 2007

AbstractA limnological study was carried out on a pair of lakes within the taiga forest of interior Alaska. These lakes, Ace and Deuce Lakes, are irregular in that one of them (Deuce Lake) is meromictic, never undergoing complete circulation, and the other (Ace Lake) has a spring circulation which is confined to the surface layers and autumnal mixing is attenuated. The ionic composition is similar to lakes in the surrounding area, with somewhat higher levels of dissolved ions. The unique features of the lake system are related to the meromictic tendencies and highly colored water with rather high ionic content. Primary productivity rates are relatively high by interior Alaskan standards, and nutrient levels are high. Primary productivity is confined to the surface meter, but even so annual productivity amounts to more than 70 g C/m2‐yr.
Light‐dependent Synthesis of δ‐aminolaevulinic Acid Dehydratase During the Developmental Period of Trapella Seedlings
Authors: Yabe Akira , Takada Hideo 
Published: February 2007

AbstractMature seeds of Trapella sinensis, after removal of receptacles, were germinated for 10 days at 23°C in the dark and then were illuminated. After illumination, the activity of δ‐aminolaevulinic acid (ALA) dehydratase was determined in relation to chlorophyll synthesis, and increases in dry weight of the whole or of parts of a developing seedling. Internal programming of development was related to changes in ALA dehydratase activity on the basis of porphobilinogen synthesis. Exogenously added ALA as well as an extract of Chlorella cells promoted this activity. There was an enhancement of chlorophyll formation resulting in an enhancement of the photosynthetic rate and in an increase of growth promotion by addition of Chlorella extract.
The effect of thermal effluent upon the standing crop of an epiphytic algal community
Authors: Klarer David M. , Hickman Michael 
Published: February 2007

AbstractThe investigation of the epiphyton associated with Scirpus validus VAHL. in Lake Wabamun commenced in May 1971 and continued until the end of August 1972. Seven stations encompassing heated, partially and non‐heated areas of the lake were investigated. From July 1971 until the termination of the investigation water temperature, dissolved oxygen and water chemistry were monitored. There were no large variations in these parameters except for water temperature and dissolved oxygen levels among the stations. However, there were increases in the dissolved silica, nitratenitrogen and phosphate‐phosphorus levels during the autumn and winter months at the heated stations while at a partially heated station only dissolved silica and nitrate‐nitrogen increased. The epiphyton at all stations showed a spring maximum, a summer minimum, and a maximum in the late summer/early autumn. The spring dominants at all stations were Fragilaria capucina and Diatoma elongatum. During the late summer/early autumn maximum diatoms were dominant at the non‐heated stations while chlorophycean species were dominant at the heated stations. The heated water caused a decrease in the number of species and a corresponding increase in the importance of a few species at the heated stations. The major impact of the heated water, however, was an extension of the period of open water and the corresponding increase in mean yearly standing crop size in the heated areas.
Primary productivity, phytoplankton and limiting nutrient factors in labrador lakes
Authors: Ostrofsky Milton L. , Duthie H. C. 
Published: February 2007

AbstractThe primary productivity of some lakes and reservoirs in western Labrador was measured by the 14C method in order to determine the range of productivities and the effects of impoundment. No primary productivity data previously existed for this part of Canada. Both the primary productivity and standing crops of phytoplankton were found to be low in a newly impounded lake but later rose to levels greater than in surrounding natural lakes. In nutrient enrichment experiments, carbon was never found to be limiting but phosphorus stimulated primary productivity when added alone or in combination with nitrogen.
Abundance, growth and production of the roach (Rutilus rutilus [L.]) population in the Klíčava reservoir during the years 1964 and 1967–1972
Authors: Pivnička Karel 
Published: February 2007

AbstractDuring the years 1964 and 1967–1972 the relationship between abundance, growth and production of the roach population in the Klíčava reservoir (Central Bohemia) was studied. Significant values for correlation coefficients were found for all variables. Noticeable variations in abundance were accompanied by similar variations in growth rate. Only the ascending part of the production‐abundance relationships was examined.
Notonemouridae of Australia (Plecoptera, Ins.)
Authors: Illies Joachim 
Published: February 2007

AbstractA revision of the Australian and Tasmanian members of the family Notonemouridae is given, studying the abundant material from several Australian and European collections and additional material obtained during the author's collecting trip to Australia and Tasmania in 1966. The family of Notonemouridae was hitherto only poorly known from this area (6 species). The following text gives descriptions of 16 species, 10 of them, and 4 genera, being new to science. The larvae of this family in Australia and Tasmania live in cold springs and rivers, especially on seepage areas in high mountains, where they climb on vertical rock surfaces; the adults are able to jump by means of their hind femora.
Man‐made eutrophication in a newfoundland (Canada) harbour
Authors: Frecker Maxine F. , Davis Charles C. 
Published: February 2007

AbstractA comparative study in 1969‐1970 of the phytoplankton and certain other parameters in St. John's Harbour and Aquaforte Harbour, located on the southeast coast of Newfoundland, led to the conclusion that St. John's Harbour which receives untreated sewage as a prime source of nutrients was by far the more eutrophic. Evidence for the eutrophic state was especially observed in the central basin (Station 1) of the harbour. Here the bottom waters were deficient in oxygen especially during the summer months. Secchi disc readings were generally lower at this station, and the annual standing crop of phytoplankton was almost three times that at unpolluted Aquaforte Harbour. Also the proportion of the biomass contributed by the nannoplankton was greater in St. John's Harbour. One euglenoid occurred in bloom concentrations throughout the summer months and may possibly be considered as an indicator of organically‐polluted waters.
Über den Einfluß der Wasserstoffionenkonzentration und des Hydrogenkarbonatgehaltes auf die Ausbildung von Bergbachbiozönosen
Authors: Ziemann Horst 
Published: February 2007

AbstractOn the basis of investigations of the diatom flora and the Plecoptera, Ephemeroptera and Trichoptera fauna in two mountain brooks with different chemisms the different effects of the regional factors of the water chemism and the extraregional factors, current and temperature, on the biocoenosis is discussed. The zoocoenotic division of mountain streams is affected by the extraregional factors; the structure of the diatom associations and the distribution of individual species of the insect fauna are dependent on the regional effect of the water chemism. The correlation of the halobic indices as ecological characteristics of the diatom flora with the factors of the water chemism, pH and alkalinity, and their relationship with the distribution of some species of the insect fauna suggest that the halobic index is a useful criterion for the ecological classification of waters. Also for the judgement of the trophic conditions and the self‐purification of waters the halobic index can be regarded as an additional criterion.
The disappearance of four leaf leachates in a hard and soft water stream in South Western Ontario, Canada
Authors: Lock Maurice A. , Noel Hynes H. B. 
Published: February 2007

AbstractThe disappearance of ‘dissolved’ organic carbon (D. O. C.) leached from maple, aspen, cedar and pine leaves was followed in hard and soft stream water and hard and soft stream water plus sediment. Differences were found in the rates and extent of the disappearance of D. O. C. between the leaves and the water types. These are discussed in relation to the productivity of two extreme stream types.
Notes on the systematics and ecology of Daphnia pulex LEYDIG in Northern Canada
Authors: Meijering M. P. D. 
Published: February 2007

AbstractDaphnia populations from the region of Yellowknife (N. W. T.) on the Great Nave Lake, from Tuktoyaktuk (N. W. T.) on the coast of the Beaufort Sea east of the Mackenzie‐Delta, and from Shingle Point (Y. T.) west of the Mackenzie‐Delta were described. Population diagrams were given for the beginning of September 1974. The populations found at the above mentioned sites were compared with Daphnia pulex from Spitsbergen and the German island of Spiekeroog. Though some characteristics of Daphnia middendorffiana FISCHER occurred, mainly in individuals from very northern ponds, these were always found in individuals which also possessed some of the characteristics of Daphnia pulex. In every pond, specimens with characteristics of Daphnia middendorffiana lived together with other individuals resembling Daphnia pulex. Males were found in three out of the four visited ponds on the shore of the Arctic Sea, and were apparently Daphnia pulex. All the material sampled in northern Canada was regarded as belonging to Daphnia pulex LEYDIG 1860 emend. RICHARD 1896. There was evidence, that characteristics of Daphnia middendorffiana develop under the influence of environmental conditions, such as food supply. Daphnia magna STRAUS was found far north of the arctic circle.
Chloridzellen der Larven von Caenis diminuta WALKER (Ephemeroptera, Caenidae) bei unterschiedlicher Salinität
Authors: Wichard Wilfried , Tsui Philip T. P. , Maehler‐V. Dewall Anne 
Published: February 2007

AbstractThe larvae of Caenis diminuta WALKER (Ephemeroptera, Caenidae) have coniform chloride cells which are involved in osmoregulation. The number of chloride cells varies according to salinity conditions of the surrounding waters. The larvae from brackish water have less chloride cells than the larvae from fresh water.
Egg size and duration of embryonic development in Crustacea
Authors: Steele D. H. , Steele V. J. 
Published: February 2007

AbstractThe duration of embryonic development is inversely correlated with egg size in Crustacea. Development is faster in amphipods and mysids than in decapods, isopods and cumaceans of the same size. The relationships are of considerable significance in the ecology of these animals.
Some Effects of a Power Plant Effluent on Estuarine Epibenthic Organisms
Authors: Young James S. , Frame Ann B. 
Published: February 2007

AbstractA study using the submerged test panel method was conducted at the Oyster Creek Nuclear Generating Station near Barnegat Bay, New Jersey to investigate effects of the heated effluent on epibenthic communities. Test panels were placed in the intake and discharge canals and collected using SCUBA at 28, 84, 168 and 335‐day intervals between October 1970 and October 1971. Exposed panels were replaced by clean panels upon collection.Faunal resemblance, both between stations during a sampling date and within stations from one sampling date to the next, was low. Numbers of species were higher at the discharge station than at the intake station from late fall to early summer and lower from midsummer to early fall. Overall differences in diversity at the two stations could not be detected. The optimum temperature for growth of Balanus sp. was approached more closely during winter in the discharge canal than in the intake canal where growth was retarded by cold water. Balanus eburneus appeared to have an extended breeding season. Because of dilution of the discharged water with cooler intake water through a plant bypass system during the summer, the effluent was not seriously harmful to amphipod reproduction. Season abundances of numerous invertebrates at both stations are reported and possible power plant effects are discussed.
Biohydrodynamics and Ecology of Life Forms of Pelagial
Authors: Aleyev Yu. G. 
Published: February 2007

AbstractThe relation between inertial forces and frictional forces characterizing the pattern of movement of plankton and nekton organisms, respectively, and expressed by the Reynolds number Re may be used as a base for classifying the life forms of the pelagial. The upper limit for the existence of euplanktic forms connected with devices for increasing the hydrodynamic resistance and ensuring passive floating with the least expenditure of energy corresponds to Re values ≦5,0 · 105. The upper boundary of the nektoplankton is in correspondance to Re ≦2,0 · 107. The organization of nekton organisms capable of active directed horizontal movement and with devices for reducing the hydrodynamic resistance is in accordance with Re >5,0 · 103, as a rule is in accordance with Re > 105.
Influence of Sediment Inflow on Phytoplankton Primary Productivity in Lake Tahoe (California‐Nevada)
Authors: Tilzer Max M. , Goldma Charles R. , Richards Robert C. , Wrigley Robert C. 
Published: February 2007

AbstractLight, nutrient concentrations and phytoplankton photosynthesis were studied in a Lake Tahoe sediment plume during maximum spring runoff. They were compared with conditions in clear lake waters not influenced by inlets. In the plume, nutrient concentrations increased in proportion to sediment density whereas light transmission of water was reduced with little effect on the spectral composition except for red light. Light inhibition of photosynthesis at the lake surface was less pronounced in the plume than in clear water and light limitation occurred more rapidly in deeper layers. Evidence from both lake experiments and laboratory bioassays suggests that iron had the greatest stimulatory effect on both photosynthetic activity and biomass growth at maximum sediment densities near the stream inlet.Because of less surface inhibition, photosynthetic light energy utilization efficiency was usually higher in the sediment plume which occurred in relatively shallow areas near the shore. In order to estimate overall effects of enhanced turbidity associated with nutrient loading on Lake Tahoe's primary productivity, profiles taken in shallow areas near the lakeshore were extrapolated to the maximum depth of photosynthesis. Light limitation would cause decreasing productivity, but nutrient stimulation would make this effect less pronounced. The overall effect would depend on the extent of sediment loading relative to nutrient loading.
Dynamics of Spatial Pattern for the Gastrotrich Tetranchyroderma bunti in the Surface Sand of High Energy Beaches
Authors: Nixon David E. 
Published: February 2007

AbstractThis paper is a quantitative study of the spatial pattern of the intertidal gastrotrich. Tetranchyroderma bunti, and its migration pattern during a tidal cycle on three high energy beaches of Bogue Banks, North Carolina, USA. Included in the study were the macrodistribution and micro‐distribution. T. bunti is gregarious and forms a clumped spatial pattern in the sand. The four clump sizes found were 2.2, 3.3, 4.4, and 5.5 cm with a ratio of 9: 6: 4: 1, respectively. The spatial pattern of these clumps suggests that the general spatial pattern of the population in its most dense area is aggregated clumped. Field experiments show that this is a stable pattern during at least part of the low tide period, and laboratory experiments suggest that the low water content of the sand at low tide contributes to this stability by decreasing the movement of the gastrotrichs. A significant difference (p<0.05) was found in the density of the gastrotrichs parallel to the shore line, but part of this difference was due to local shifts in the spatial pattern of the population instead of a change in the longshore abundance. T. bunti showed a tidal migration pattern opposite to that of the ground water movement.