bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE BIOLOGICAL EFFECTS OF OIL POLLUTION IN A RIVER1
Authors: McCauley Rita N. 
Published: March 2010

Physical, chemical, and biological conditions in the water and sediments of Muddy River, Massachusetts, were observed from autumn 1961 through summer 1963 to determine the effects of oil pollution on biological activity. Samples from above, in, and below the polluted area were collected and analyzed.The heavy bunker oil pollutant formed a thin partial film on the surface of the water that partially excluded the oxygen from the water but not sufficiently to destroy developing plankton. Low biochemical oxygen demand correlated with consistently high concentrations of oil in the sludge in the polluted region indicating slow decomposition of the oil by microorganisms.The oil was markedly toxic to the plankton and to the macrofauna of the sediments. The following plankters tolerated the pollution even during periods of highest oil concentration: Lyngbya, Oscillatoria, Ankistrodesmus, Chlamydomonas, Closterium, Gonium, Scenedesmus, Asterionella, Cyclotella, Fragilaria, Meridion, Navicula, Tabellaria, Euglena, Trachelomonas, Vorticella, Asplanchna, Keratella, Polyarthra, Cyclops, and Nemata types. In the sediments, Gammarus, Agrion nymphs, and Dugesia were unable to tolerate conditions in the region of oil pollution while Tubifex, Tendipes larvae, Nemata, and Hirudinca types were tolerant and remained.
TISSUE ANALYSIS AS A MEASURE OF NUTRIENT AVAILABILITY FOR THE GROWTH OF ANGIOSPERM AQUATIC PLANTS1
Authors: Gerloff G. C. , Krombholz P. H. 
Published: March 2010

A tissue analysis technique was used to evaluate nitrogen and phosphorus supplies in natural waters for the growth of angiosperm aquatic plants. Tissue content of nitrogen and phosphorus was employed as an index of element availability in lakes from which plants were collected. This required establishment in the laboratory of the critical level for each element, that is, the minimum tissue content associated with maximum growth.To establish critical levels, a system was developed for culturing algae‐free plants in a synthetic nutrient medium. The critical nitrogen content for the several species studied was approximately 1.3%; the comparable phosphorus value was 0.13%.The nitrogen and phosphorus contents of 13 species of aquatic plants collected during the summer from nine lakes were compared with the critical concentrations. In nine samples obtained mostly during periods of heaviest plant growth, the phosphorus content was at or below the critical level; in no sample was the nitrogen content less than the critical concentration. The results indicated that in all but one of the lakes, phosphorus supply was more likely to limit higher aquatic plant growth than was nitrogen.The primary importance of this study is as an initial step in the development of a satisfactory technique for evaluating nutrient supplies in natural waters.
A DETAILED ANALYSIS OF BIOLOGICALLY IMPORTANT SUBSTANCES IN A PROFILE OFF SOUTHERN CALIFORNIA
Authors: Holm‐Hansen O. , Strickland J. D. H. , Williams P. M. 
Published: March 2010

Detailed vertical profiles of salinity, temperature, 10 soluble inorganic and organic constituents and six particulate organic constituents have been determined at a station over the Santa Catalina Basin. Irregularities in the Profiles suggest nine “layers” in the 1,300 m column of water; four of the layers are clearly defined by physical properties and the remainder largely by variations in their dissolved organic matter and materials such as phosphate, nitrate, and silicate.The ratio of carbon oxidized to nitrate and to phosphate formed in the same water averaged 100 : 18.4 : 3.0 by weight, a ratio to be expected from the oxidation of oceanic phytoplankton. The average ratio by weight of carbon to nitrogen to phosphorus in dissolved organic compounds was 100 : 11 : 1, and the ratio for the particulate organic matter was similar.Except in the top 200 m, the amount of dissolved organic carbon was about 20% of the amount of carbon oxidized and the amount of particulate organic carbon was about 10% of the amount of dissolved organic carbon in the same water. Other ratios are given for silicate, nitrogen, and phosphorus.
DIURNAL PERIODICITY IN THE PHYTOPLANKTON ASSEMBLAGE OF A HIGH MOUNTAIN LAKE1
Authors: Tilzer Max M. 
Published: March 2010

Diurnal changes in phytoplankton stratification and photosynthesis were studied at all seasons. The dominant flagellates usually ascend in the evening and at night and migrate downward with increasing light intensities. Maximum migratory speeds are higher than 1 m hr−1 and almost independent of cell size. The vertical stratification pattern of flagellates is the result of varying upward and downward migrations, but the vertical stratifications of nonmotile species depend on the turbulence of the water.Over the day the mean photosynthesis of the entire water column varies in about the same proportions as the input of light energy. At a given depth algae seem to be adapted to the daily mean value of light intensity. Near the lake surface, around noon (1000–1400 hours), photosynthesis is considerably reduced due to downward migration, light saturation, and light inhibition—all caused by high light intensities—but at greater depths the utilization of light energy frequently is increased. During low light periods (early morning, evening) suboptimal light intensities in deeper layers of the lake cannot be utilized as effectively. By phototactic vertical migrations, the diurnal shifts of light energy utilization can be partly compensated.
DIATOMS IN ALKALINE, SALINE LAKES: ECOLOGY AND GEOCHEMICAL IMPLICATIONS1
Authors: Hecky Robert E. , Kilham Peter 
Published: March 2010

Six diatoms achieve dominance in 26 alkaline, saline lakes in East Africa. There is a pronounced tendency for these species to replace each other as alkalinity increases. Cyclotella meneghiniana is usually dominant in less concentrated lakes and Nitzschia frustulum is favored as the alkalinity exceeds 80 meq liter−1. Coscinodiscus rudolfi and Navicula elkab are occasionally dominant at intermediate alkalinities. Navicula elkab is usually subdominant when N. frustulum is dominant. Most of these species when dominant are considered functionally planktonic in these waters. The presence of the cyanophyte Oscillatoria (Arthrospira) platensis in bloom seems to be a prerequisite for N. elkab and N. frustulum to enter the plankton. There is some evidence that the anionic composition of these lakes may be selective for some of the benthonic species.Geochemical data indicate that the production and preservation of diatom frustules appear to control silica concentrations in the waters. Relatively poor correlations were observed between sodium and silica and between pII and silica. These data have important implications for theoretical models of geochemical evolution in closed basins. Little or no dissolution of fossil diatom frustules was observed in the sediments of these highly alkaline, high pH waters.
CIRCULATION AND SALINITY DISTRIBUTION IN THE SOUTHERN PART OF THE SUEZ CANAL
Authors: Morcos Selim A. , Messieh S. N. 
Published: March 2010

Results of 14 hydrographic sections along the southern part of the Suez Canal between Suez Bay and Great Bitter Lake from April 1964 to April 1965 are generally in agreement with previous sections taken 10 years before (1954–1955). A northward current prevailed from November to July and a southward current dominated from 15 August to 15 October, pushing the saline water mass (44%) to Suez Bay.Two sections on successive days during September 1964 showed differences explained by the sampling time in relation to the tides. In certain stations low salinity occurred after high water and high salinity after low water, mainly due to reversible tidal currents: The northward current at high water carries low salinity water from Suez Bay. Saline water from the Bitter Lakes moves southward during the ebb and attains its maximum at low water.No increase in salinity was observed in Suez Bay during summer 1966, contrary to all preceding observations in 1924, 1934, 1954, and 1964. Two sections taken in the southern canal in September 1966 did not indicate the usual reversal of currents toward the south. This confirms a previous observation that a change in the current regime in the Suez Canal took place in 1966, just after completion of the Aswan High Dam.
CHARACTERISTICS OF THE NEARSHORE ENVIRONMENT OFF THE SOUTH COAST OF RNVERS ISLAND, ANTARCTIC PENINSULA1
Authors: Warnke Detlef A. , Richter Joseph , Oppenheimer Carl H. 
Published: March 2010

Sediment and water samples were taken at 17 stations in a nearshore area off the southern coast of Anvers Island, Antarctic Peninsula. The sediments are diamietons and display great lateral variability. Their organic carbon content falls within the range of values for oceanic sediments; variations can perhaps be explained in terms of specific local environments of deposition. Silica concentrations in the interstitial water of these sediments seems to be controlled by biogenic processes of sedimentation.Bacteria are preferentially associated with sediments rich in clay‐sized materials and show little or no correlation with organic carbon in these samples; the surface properties of the fine sediment may be important. Bacterial numbers in the water column are similar to those reported for open‐ocean areas below 200 in in lower latitudes. Nutrient values are high, but many nitrite values are low relative to nitrate as in lower latitudes before the growth season and in the open ocean below the euphotic zone. These similarities may indicate that primary productivity at the time and place of investigation was low.
THE THERMAL REGIME OF LAKE LANAO (PHILIPPINES) AND ITS THEORETICAL IMPLICATIONS FOR TROPICAL LAKES1
Authors: Lewis William M. 
Published: March 2010

A study of temperature profiles, climatic records, and chemical data for Lake Lanao, a low‐altitude tropical lake, over 14 months shows that the annual pattern of heat distribution depends partly on a seasonal air temperature minimum and partly on nonseasonal climatic changes. The lake circulated during January and February at the time of seasonal cooling, was intermittently stable during March and April, and was stratified during all other months. During stratification the principal thermocline achieved equilibrium with storm winds at 40–50 m. Secondary and tertiary thermoclines repeatedly split the epilimnion into an upper turbulent layer and a lower stagnant layer for periods up to 2 months, but were displaced or dissipated at irregular intervals by storms. The term atelomixis is proposed to denote the mixing of chemically divergent layers during stratification.Changes in the shape of thermal profiles in Lake Lanao include sharpening of thermodines by wind and convection, smearing of thermoclines by internal water movements, unstable thermal inversions due to cooling at the surface, and stable thermal inversions on the bottom that result from heat retention during cool weather.
WAX ESTERS IN TROPICAL ZOOPLANKTON AND NEKTON AND THE GEOGRAPHICAL DISTRIBUTION OF WAX ESTERS IN MARINE COPEPODS1
Authors: Lee Richard F. , Hirota Jed 
Published: March 2010

Analyses of zooplankton and nekton from the central South Pacific showed that surface and epipelagic zooplankton had small amounts of neutral lipids, mainly triglycerides, while deep‐water tropical copepods had wax esters as the major lipid type, presumed to function as a reserve storage.The total lipid content and wax esters of tropical copepods captured at about 500 m were significantly lower than those of species from high latitudes. The median percentage of wax esters increased progressively from tropical to polar latitudes in nine species of Calanus and five or six species of Euchaeta. Deep‐living tropical copepods had the same median percentage of wax esters as mesopelagic and bathy pelagic copepods from a subtropical station.Caridean and penaeidean decapods and euphausiids showed less than 5% wax esters. Gnathophausia, a mesopelagic mysid, stored wax esters (32% of the lipid). A deep‐water chaetognath (Eukrohnia sp. ?) and a mesopolagic cranchiid squid had over 25% wax esters. Fish species not previously analyzed containing more than 10% wax esters included three myctophids and members of the Astronesthidae, Cheilodipteridae, Gonostomatidae, Paralepididae, Scopelosauridae, and Sternoptychidae.
Application of a model to an estuarine ecosystem
Authors: WYATT T. , QASIM S. Z. 
Published: March 2010

The annual cycles of primary production and plankton succession in the Cochin Backwater, South India, are examined in the context of a model given by Margalef. The increased flushing of the estuary caused by the southwest monsoon is seen as the main driving force behind the changes which take place.Fish production in the estuary is high when compared with primary production; it is suggested that detritus is an important component of the food web.
Determination of calcite: aragonite ratios in mollusc shells by infrared spectra1
Authors: COMPERE EDWARD L. , BATES JOHN M. 
Published: March 2010

Calcium carbonate structure in mollusc shells can be determined by infrared spectroscopy. Infrared analysis is easier and less expensive than most other current methods for macroscopic analysis of the structures in gross calcium carbonate.Shell specimens from 22 river species were shown to be entirely aragonite; the composition of two shells of Strombus gigas Linnaeus was primarily aragonite with a thin surface layer of calcite and that of a fossil oyster shell (Ostrea sp.) was entirely calcite.
DISTRIBUTION OF CORAL REEFS IN THE PEARL ISLANDS (GULF OF PANAMA) IN RELATION TO THERMAL CONDITIONS1
Authors: Glynn Peter W. , Stewart Robert H. 
Published: March 2010

The hypothesis that coral reefs are largely confined to the north and east sides of islands because of favorable thermal conditions was tested and confirmed in the Pearl Islands, Panamá.The growth rate of Pocillopora damicornis, the chief reef‐building species, declined markedly or ceased on shores exposed to temperatures in the range 20‐21°C, when median growth rates dropped to below 1.0 mm month‐1 and a variety of alien benthic species invaded and overgrew the branch tips of corals. High rates of bedload sedimentation on exposed shores and a high organic matter content of sediments on reefs did not affect coral growth. Differences in coral growth preceding and following upwelling were correlated with seasonal variations in sky cover.Other factors affecting coral growth and reef development include the ability of corals to feed and reproduce at low temperatures, the influence of turbulent conditions, the capacity of a reef structure to modify the surrounding thermal regime, and the effects of attrition due to corallivores.
FILTERING RATE INHIBITION OF DAPHNIA PULEX IN WINTERGREEN LAKE WATER1,2
Authors: Crowley Philip H. 
Published: March 2010

The difference between the effects of seston concentration and dissolved substances on the rates of filtering and feeding by Daphnia pulex in the water of a small eutrophic lake was studied during late summer (16–18 August 1971) .Low concentrations of 32P‐labeled yeast, Rhodotorula sp., were added to whole lake water, lake water filtrate, and seston resuspended in filtered tapwater to measure grazing by field‐collected animals. Lake water seston limited grazing rates at ambient concentration; “dissolved” inhibitors capable of limiting filtering rates at lower seston concentrations were also present, but their effects were masked by high seston concentration. Possibly these dissolved substances were excreted into solution by the dense phytoplankton population, notably including Anabaena and Anacystis.Mathematical expressions for filtering and feeding rates as functions of seston concentration are derived from Holling’s disc equation and fit to the data.
The probable occurrence of hydroxylarnine in the water of an Ethiopian lake.
Authors: BAXTER R. M. , WOOD R. B. , PROSSER M. V. 
Published: March 2010

Fresh samples of water from all depths of Lake Pawlo, a moderately alkaline Ethiopian crater lake, frequently showed a marked increase in nitrite ion content after brief boiling. This did not occur, or was greatly reduced, in samples kept overnight before boiling.It is suggested that this was due to the presence of hydroxylamine. At the original pH of the water, oxidation of the hydroxylamine in the samples leads to nitrous oxide. When the sample is boiled, carbon dioxide is driven off and pH is increased. At this higher pH the oxidation of hydroxylamine follows a different pathway.Hydroxylamine may be a more frequent constituent of lake waters than has been assumed.
Uptake of selenium by aquatic organisms
Authors: SANDHOLM M. , OKSANEN H. E. , PESONEN L. 
Published: March 2010

The Se content of aquatic organisms was lowest in aquatic plants, varying from 0.02 to 0.14 ppm (dry wt). Plankton samples contained from 1.1 to 2.4 ppm, fishes cultured in ponds 0.5 to 0.9 ppm, and fishes from natural environments 1.0 to 2.9 ppm.The phytoplankter, Scenedesmus dimorphus, actively concentrated 75Se‐selenomethionine, but neither actively nor passively concentrated inorganic selenite. The zooplankton, consisting mostly of Daphnia pulex, absorbed 75Se from selenite. In aquariums fish concentrated only a small amount of organic or inorganic Se directly from water, but did concentrate Se from food.
REGRESSIONS BETWEEN BIOLOGICAL OCEANOGRAPHIC MEASUREMENTS IN THE EASTERN TROPICAL PACIFIC AND THEIR SIGNIFICANCE TO ECOLOGICAL EFFICIENCY1
Authors: Blackburn Maurice 
Published: March 2010

Simple regressions of various standing stocks on each other and on primary productivity were compared by covariance analysis for different seasons, latitudes, and longitudes in the eastern tropical Pacific. The stock of zooplankton varies significantly with that of chlorophyll a to a power <1.0 in all seasons and areas, and it is shown that a similar relation probably exists between the corresponding rates of daily production. A similar relation holds in the regression of standing stock of fish‐cephalopod micronekton, suitably lagged, on stock of zooplankton. Thus the relative amount of organic matter transferred from one trophic level to another probably decreases with an increase of stock and production at the lower level, so that ecological efficiency is higher in oligotrophic than in eutrophic situations, in tropical oceans.Standing stock of chlorophyll a varies significantly with primary productivity to a power <1.0. The stock of crustacean micronekton sometimes varies with the stock of chlorophyll a to a power >1.0, which is interpreted as a feeding aggregation.
EVIDENCE FOR SEX PHEROMONES IN PLANKTONIC COPEPODS
Authors: Katona Steven K. 
Published: March 2010

When in the presence of potential mates, males of the copepods Eurytemora affinis, Eurytemora herdmani, and Pseudodiaptomus coronatus performed mate‐seeking behavior which appeared to be oriented. Males of E. affinis and P. coronatus located stationary females from up to 20 mm away. Males of E. affinis also chased and found secured females moved by a mechanical device. Eurytemora affinis males performed mate‐seeking behavior toward females of all three species, and, to some extent, toward other conspecific males. However, they attempted to copulate with conspecific females most frequently. Evidence suggested that males detected other copepods by means of diffusible chemicals.Males of the three species showed copulatory behavior toward secured females (or males) of their own species in about 80% of trial presentations. They usually did not try to copulate with animals of the other genus. Males of E. affinis were less selective between specimens of the two Eurytemora species than were E. herdmani males. Relatively specific chemical substances, active on contact, were probably the main factors eliciting copulatory behavior from males.
CHANGES IN THE CONCENTRATION OF SOLUBLE AND PARTICULATE IRON IN SEAWATER ENCLOSED IN CONTAINERS1
Authors: Lewin Joyce , Chen Ching‐hong 
Published: March 2010

Seawater samples collected along the Washington coast (Puget Sound) were used as sources of naturally occurring iron fractions. Once the water was enclosed in a container, approximately half of the iron in the soluble fraction disappeared and could be quantitatively accounted for by an increase in the iron of the particulate fraction; when the particulate fraction was removed at zero time, soluble iron likewise disappeared, but most of it went onto the walls of the container. The changes were independent of temperature and soluble iron disappeared even when the particulate fraction (including organisms) was removed at zero time, ruling out biological activity. These changes were completed in 30–40 hr.Part of the soluble fraction was ferrous iron. Addition of Na2‐EDTA stabilized a portion of the soluble iron equivalent to the ferrous content and kept it from disappearing during the experiment. Ferrous iron may be present in a chelated form in the natural seawater.
Decomposition of marine copepods1
Authors: HARDING GARETH C. H. 
Published: March 2010

Killed copepods decomposed within 11 days in 4°C Halifax water and within 3 days in 22°C Sargasso Sea water. In both cases initial infection occurred on the exoskeleton and apparently progressed into the organisms through the mouth. The urosome and internal extremities were the last to be attacked.Collection of surface corpses by net is thought to be impossible after the first day of death in subtropical waters and beyond the sixth day in temperate coastal waters.
FLUSHING OF COASTAL EMBAYMENTS BY CHANGES IN ATMOSPHERIC CONDITIONS1
Authors: Heath R. A. 
Published: March 2010

The circulation in several coastal embayments on the east coast of Nova Scotia, Canada, induced by changing atmospheric conditions is discussed. In summer and fall when the bays have essentially a two‐layered vertical density distribution, quasi‐periodic changes in wind and atmospheric pressure associated with moving atmospheric disturbances produce a quasi‐periodic flow which is out of phase between the layers.Correlation between the observed flow and atmospheric parameters together with results from a simple two‐layered model indicate that the flow is probably produced by wind forcing. The observed speeds in the flow are of the same size as those in the mean circul ation.The generation of the fluctuating flow does not appear to depend on the particular form of the bays and therefore this type of flow should be produced in bays on other coasts where periodic changes in atmospheric pressure associated with wind variation are observed.
THE EFFECT OF WATER MOTION ON ALGAL SPORE ADHESION1,2
Authors: Charters A. C. , Neushul M. , Coon D. 
Published: March 2010

The effects of water motion on the attachment of algal germ cells to benthic substrates were studied. Water motion was measured in the field and the forces on a germ cell attached to a substrate surface computed. Laboratory apparatus for simulating wave surge was developed, calibrated, and used for experiments on the spore attachment process. A“waterbroom,” producing water motion over the surface of a submerged substrate in a laboratory aquarium, closely simulates wave surge; it was calibrated by measuring static and dynamic pressures in the substrate’s boundary layer and determining whether the layer was laminar or turbulent.Preliminary tests with the waterbroom indicate that the adhesion of carpospores of Agardhiella tenera to a clean glass surface increases wih residence time, while that of Cryptopleura violacea decreases. Improved experimental data on Gracilariopsis sjoestedtii showed an increase in adhesiveness with residence time, from 10 hr to an asymptotic limit at 20. Once attached, the Gracilariopsis spores adhere firmly, resisting removal by shear forces nearly 100 times their weight.