bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Various Factors on the Toxicity of Sodium Pentachlorophenate to Fish1
Authors: CRANDALL CATHERINE ANN , GOODNIGHT CLARENCE J. 
Published: March 2010

The effects of various factors on the toxicity of sodium pentachlorophenate to the fathead minnow (Pimephales promelas) were studied. As a base for comparison of the effects of various factors, the TLm for 24 hours was first investigated. It was found that 0.4 ppm killed all the fish, while they all lived at 0.20 ppm. The range between these two extremes was so slight that it was difficult to determine an exact 24‐hour TLm; it was found to lie between 0.32 and 0.35 ppm.One ppm concentration of sodium pentachlorophenate was used for investigating the effect of pH on the toxicant at 18° C. It was found that the lower the pH of the test solution, the more toxic the material became. The mean survival time for 50% of the experimental animals at a pH of 5.9–6.0 was 28 ± 1.7 minutes; at 7.5–7.6, it was 80.7 ± 2.3 minutes; and at 8.9–9.0, the fish lived for 24 hours.Temperature effects were investigated using a solution of one ppm of sodium pentachlorophenate at pH 7.5–7.6. It was found that the higher the temperature, the more toxic the sodium pentachlorophenate is to fish.The mean survival time of 50% of the minnows at 10° C was 260.4 ± 10.2 minutes; at 18° it was 80.7 ± 2.3 minutes; and at 26° it was 46 ± 2.1 minutes.
Effect of Water Clarity on Albacore Catches
Authors: MURPHY GARTH I. 
Published: March 2010

The numbers of albacore (Germo alalunga) taken by gill‐netting and surface trolling are seriously affected by the transparency of the water. Observations assembled from a fishing cruise between Hawaii and the Aleutians in 1956 and from a cruise off the Pacific coast of North America in 1957 showed that the efficiency of the troll was greater in clear water than in more turbid water. Very likely this increase in efficiency is a power function of the change in transparency. Though the data are not so convincing, the results suggested that the gill net fishes more efficiently in turbid water. The ratio of troll catch to gill‐net catch bears the following relation to a reciprocal function of the extinction coefiicient—

urn:x-wiley:00243590:media:lno1959410086:lno1959410086-math-0001

Since the theoretical maximum power function of the troll catches alone is about 3, the residual of 1.55 may be associated with the reverse effect that water clarity has on the efficiency of the gill net.These data are discussed in relation to evaluating the abundance of any species of fish when the method of assessment involves visual responses. In addition, the possibility is discussed that water clarity may be an important ecological factor in the ocean in that the efficiency of sight feeders will be reduced as turbidity increases.
Stratigraphic Distribution of Amino Acids in Peats from Cedar Creek Bog, Minnesota, and Dismal Swamp, Virginia1
Authors: SWAIN F. M. , BLUMENTALS A. , MILLERS R. 
Published: March 2010

The concentration of several alpha‐amino acids obtained by acid hydrolysis at various levels in Cedar Creek Bog and Dismal Swamp has been determined. Seven amino acids are consistently present in the natural accumulations: glycine, aspartic acid, glutamic acid, threonine, alanine, valine, and leucine. Alanine occurs in the highest concentrations, attaining about 22 µmol/g in the samples investigated. Free amino acids were absent or very rare in both the bog waters and waters squeezed from the peats. Attempts to detect proteins in these substances by means of paper electrophoresis were unsuccessful. Fibrous proteins may be present, however.In both peat deposits there is a greater concentration of amino acids at depths of a few feet than in the uppermost peat layers. Hydrolysis of a humic acid preparation from Minnesota peat yielded the same suite of amino acids given above. It is therefore suggested that the amino acids in our peat hydrolyzates mainly occurred adsorbed by, or linked to, the humic acid micelles rather than as proteinaceous compounds.The distribution of amino acids in Cedar Creek Bog peat suggests two periods of trophication, one beginning approximately 12,000 years ago in Mankato time and ending with the so‐called thermal maximum perhaps as late as 6,000 years ago, the other beginning after the thermal maximum and continuing to the present. Evidence of more than one cycle of peat development in the Lake Drummond area of Dismal Swamp is lacking.
Two Sources of Error in the Oxygen Light and Dark Bottle Method1
Authors: PRATT DAVID M. , BERKSON HAROLD 
Published: March 2010

Rates of oxygen uptake per bacterial cell in dark bottles containing bacteria but no phytoplankton were applied to the bacterial population of the dark bottle in two‐day light and dark bottle experiments and showed that, in the temperature range 11–21°C, bacteria were responsible for 42.5% to 62.5% of the total respiration customarily attributed to the phytoplankton. Failure to correct for bacterial respiration results in “net photosynthesis” values that are erroneously low by the same amount.Large changes commonly occur in the bottled populations during a two‐day light and dark bottle experiment: in 22 routine experiments diatoms in the light bottle increased an average of 264%/day and the total population increased 72%/day, while in the dark bottle flagellates and the total population usually decreased slightly. Respiration and net and gross photosynthesis per unit volume of water are therefore probably not the same inside and outside the bottles. The rapid multiplication of diatoms in the light bottle is due to an accelerated regeneration of nutrients by the bacteria attached to the bottle walls, as shown by comparison of diatom growth in water previously conditioned by bacteria with growth in water not so conditioned.
Chlorophyll and Productivity in a Mountain River1
Authors: MCCONNELL WILLIAM J. , SIGLER WILLIAM F. 
Published: March 2010

Chlorophyll was sampled on the shallow, rocky, canyon section of Logan River—a swift, clear, calcareous mountain river in the Middle Rocky Mountains of northern Utah. Chlorophyll extractions were made by immersing entire rocks supporting algae in acetone. The average quantity of chlorophyll per m2 of bottom of the canyon section of Logan River was 0.30 grams. Downstream supplementary stations supported 3 to 4 times as much chlorophyll as the canyon section. No significant difference existed between means of chlorophyll samples in fall and late winter and between the upstream and downstream portions of the canyon section.Annual gross primary production equal to about 1.2 kg per m2 was estimated from the relation of chlorophyll to photosynthesis in light and dark jar experiments. A standing crop of 25 grams of dry plant biomass per m2 was determined from the chlorophyll dry weight ratio of samples of the community. Average standing crops (dry wt.) of insects and fish were 5 and 1.6 per cent, respectively, of the producer biomass or average standing crop of algae.Production of chlorophyll on artificial substrata (concrete rocks) showed no close relationship with either insolation or water movement within the range of values encountered in the Logan River.
Trace Analysis of Marine Organisms: A Comparison of Activation Analysis and Conventional Methods1
Authors: FUKAI RINNOSUKE , MEINKE W. W. 
Published: March 2010

A comprehensive review has been made of the abundance values reported for all trace elements in seaweed, mollusks, crustaceans, fishes, and in sea water. The sensitivities of standard spectrophotometric and flame photometric techniques for such analyses have been compared with the sensitivities expected from activation analysis techniques.Activation analysis eliminates the problem of contamination by reagents and is particularly useful for the analysis of minute traces. While it is not an “all purpose” method for every element, it does show promise of increasing the detection sensitivity for a number of elements by factors of 10, 100, or more as well as making possible the discovery of elements not previously found in marine organisms, such as elements of the ruthenium or platinum groups and indium.
Midwater Trawling Studies in the North Pacific1
Authors: ARON WILLIAM 
Published: March 2010

A modified version of the Isaacs‐Kidd midwater trawl was used for 149 exploratory hauls in the Northeastern Pacific at depths ranging from 20 to 250 meters. Catches are discussed in terms of such factors as diurnal migration, seasonal variation, patchiness, and geographic variation.There was wide difference between day and night hauls. Geographic variation was marked. Abundance of plankton and fish decreased with increasing distance from the Washington coast, but increased again just south of the Alaskan peninsula. Northward and seaward there was a decrease in number of fish species. There appeared to be definite correlation between catches and an oceanographic boundary at approximately 50° North.A number of rare fish, one new species, and two leptocephalus larvae were taken.Consistency of results and close relationship of oceanographic and biological data suggest the usefulness of the midwater trawl as a valuable tool for future investigations of plankton ecology.
The Respiration of Some Planktonic Copepods
Authors: RAYMONT J. E. G. 
Published: March 2010

The respiratory rates of two neritic planktonic copepods, Centropages hamatus and Temora longicornis obtained from the northeast coast of the United States, have been shown to he very similar to the rates determined for British specimens, provided due allowance is made for the difference in size of the animals.The relationship previously suggested between respiratory rate and length for planktonic copepods, appears to hold for these two American species, but in the case of Temora the modified formula suggested by Gauld and Raymont (1953) must be used. The relationship applies also to Pseudocalanus minutus. Tortanus discaudatus has been found to have a higher rate as determined experimentally. It is suggested that this high rate is associated with the carnivorous feeding of this copepod.Experiments on the respiration of Eurytemora herdmani show that females have a considerably higher oxygen demand than males, though the difference becomes only slight when due allowance is made for the difference in size between the sexes. Some experiments conducted on the respiratory rates at 15° and 20°C suggest that Eurytemora herdmani, in contrast to the other calanoids investigated, does not show any increase in respiratory rate beyond 15°C.In the laboratory lack of feeding in Tortanus is associated with a marked decline in respiratory rate; to a lesser extent a reduction in respiration with lack of food has been observed in Centropages hamatus.
INTERTIDAL ZONATION IN POPULATIONS OF MYA ARENARIA1
Authors: Matthiessen George C. 
Published: March 2010

Observations over a 2‐year period on the distribution of two successive year‐classes of Mya arenaria in a tidal area near Quincy, Mass., indicated that young clams 2–15 mm in length were subject to appreciable changes in location in intertidal areas. Such changes involved a shoreward displacement of the members of the population as they exceeded 5 mm in length, with a marked tendency for successive populations ultimately to become concentrated near an abrupt change in the beach profile.The similarities between the patterns of clam and surface sediment distribution in this area are discussed, and it is suggested that, as in the case of sediment particles, hydrodynamic forces are primarily responsible for the zonation of Mya populations in intertidal areas.
SESTON COMPOSITION IN TWO FRESIIWATER POOLS
Authors: Moss Brian 
Published: March 2010

Seasonal changes in organic components of the seston were measured in two small pools during two years. In one pool, little disturbed by wind and having few aquatic macrophytes, about a third of the seston organic matter was detritus, derived largely from marginal sediments. A small fraction in summer was probably bacteria or microzooplankton. Positive correlations between chlorophyll a, carotenoids, particulate carbohydrate, and particulate organic matter were highly significant. Seasonal changes in ratios of chlorophyll a to organic matter and chlorophyll a to carotenoids were much smaller than the ranges for these ratios from laboratory cultures.The second pool, shallower and more exposed than the first, was almost entirely colonized by Equisetum fluviatile, whose epiphytic communities contributed much organic matter to the seston. About half of the organic seston was living algae, of which many cells may have been detached epiphytes. Bacteria caused large increases in particulate organic matter in summer. The complex origins of the seston precluded the detailed analysis of changes in various components that was possible for the first pool.
GNOTOBIOTIC CULTURE AND PHYSIOLOGICAL ECOLOGY OF THE MARINE NEMATODE RHABDITIS MARINA BASTIAN1
Authors: H. Tietjen J. , J. Lee J. , Rullman J. , Greengart A. , Trompeter J. 
Published: March 2010

The marine nematode Rhabditis marina Bastian has been isolated in gnotobiotic culture from collections of Zostera marina made in North Sea Harbor, Southampton, New York. A strain of R. marina has been maintained with three species of bacteria (Pseudomonas sp., Flavobacterium marinum, and Micrococcus sp.) for over 120 generations. A monoxenic strain with Pseudomonas sp. has been maintained for over 25 generations. The life cycle is completed in 5 days under “normal” laboratory growth conditions. Reproduction occurs over a wide (0–80‰) salinity range (the highest salinity tested) and a wide (10–38C) temperature range; optimum growth occurs at 45–55‰ and 25–30C. Normal development is oviparous, but ovoviviparous development is seen in older females. Tracer feeding and synxenic culture experiments have shown that R. marina has rather specific nutritional requirements, which seem to be completely satisfied by a relatively restricted group of microorganisms. Selected species of bacteria comprise the normal diet of this organism. Microscopic observations of intact algae in the digestive tract of the worms and failure of 32P to transfer to the worms from the ingested algae indicate that the worms are not able to digest all ingested potential food organisms.The geographical distribution of the species in relation to its physiological ecology is discussed.
CURRENTS NORTH OF BERING STRAIT IN WINTER1
Authors: Coachman L. K. , Tripp R. B. 
Published: March 2010

Four days of current record were obtained about 190 km NNE of Bering Strait during March 1968. The mean current was the same for the location as in summer, suggesting that the generally north flow from the Bering Sea to the Arctic Ocean occurs also in winter.Variations in speed and direction of the flow were identified and analyzed. The major periodic variation was due to the diurnal tidal wave, and thus the tidal wave rather than inertial currents must be the primary cause of periodic variations. The course of the tidal wave and some features of its behavior are inferred. Other variations of importance include a variation with a period somewhat greater than 2 days, probably caused by atmospheric phenomena, and fluctuations due to relatively large‐scale turbulence (periods between 5 and 60 min).
A LIQUID SCINTILLATION PROCEDURE FOR DETERMINING THE EFFECT OF SIZE ON SELF‐ABSORPTION OF 14C IN DAPHNIA PULEX1
Authors: WARD F. J. , WONG BRIAN , ROBINSON G. G. C. 
Published: March 2010

Self‐absorption coefficients for 14C in Daphnia pulex ranging from 1.1 to 2.9 mm long were determined with a liquid scintillation counting procedure. Coefficients were calculated from two regressions: that of the radioactivity of labeled whole animals on size and that of the radioactivity of labeled animals digested for 24 hr at 60C in the solubilizer NCS on size. Self‐absorption coefficients increased from 1.23 for animals with a mean body carbon content of 6.6 µg C/ individual to 2.73 for animals with 44.7 µg C/individual.If quenching is moderate and digestion complete, specific activities of small animals can be determined directly using an efficient solubilizer, eliminating the need to use self‐absorption coefficients.
INCORPORATION OF ORGANIC CARBON BY DAPHNIA PULEX
Authors: Bell R. K. , Ward F. J. 
Published: March 2010

The rate of incorporation of organic carbon by Daphnia pulex from various concentrations of 14C‐labeled phytoplankton and artificial detritus was measured both in situ in West Blue Lake, Manitoba, and in the laboratory.Incorporation of artificial detritus was independent of dissolved oxygen concentration, down to a level of 2.8 mg O2/liter, during a 4‐hr experiment. Food concentration and temperature were related, for each food type, to incorporation in multiple regression equations. Three estimates, ranging from 2.37 to 5.35 µg C individual−1 day−1, were made of daily incorporation, assuming it was similar in natural and artificial detritus. Of these amounts, from 12 to 17% was estimated to be incorporated by Daphnia below 12 m, in the zone where particulate organic matter was predominantly detritus or moribund organisms. Variations in incorporation rate were caused primarily by temperature differences encountered during vertical migration rather than by food concentration. Because vertical migration patterns varied, temperature regimes also varied, and so, consequently, did incorporation rates. The estimated contribution of detrital carbon to total daily incorporation was much less than the phytoplankton contribution but was significant.
THE EFFECT OF TEMPERATURE ON THE DEVELOPMENT TIME OF EGGS OF THERMOCYCLOPS SP., A TROPICAL CYCLOPOID COPEPOD FROM LAKE GEORGE, UGANDA
Authors: Burgis Mary J. 
Published: March 2010

The rate of egg development in Thermocyclops sp., determined in the laboratory, increases linearly from 15–30C. Above 32.5C development is retarded and, although eggs hatch at 35C, the females die after some time at that temperature, At 40C, mortality is 100% within 2 hr.The mean temperature of Lake George is computed to be 26.3C and, by extrapolation from the laboratory results, a mean development time of 36 hr is obtained. Both these means vary little throughout the year.From the work of others, it appears that the effect of temperature on egg development is similar in Mesocyclops leuckarti but less marked in several calanoid copepods.
AN EXPERIMENTAL APPROACH TO THE PRODUCTION DYNAMICS AND STRUCTURE OF FRESHWATER ANIMAL COMMUNITIES1
Authors: Hall Donald J. , Cooper William E. , Werner Earl E. 
Published: March 2010

The effects of three levels of inorganic nutrients and two predator densities on aquatic animal communities were examined in a series of twenty 0.07‐ha freshwater ponds. The treatments were cross‐classified in a randomized block design and continued over 3 years. Analyses of the responses include community composition, secondary production, and demographic description of the dominant species of both zooplankton and benthos. The fish populations and their feeding behavior are described in detail. Ancillary data on water chemistry and primary production were available.Nutrients generally increased production of the zooplankton but had little effect on community composition. Fish predation had profound effects on the diversity and size distribution of the zooplankton but only affected production at lower nutrient levels. The benthos responded markedly to nutrients during the first year, but this was not apparent the second and third years. The response of the benthos to both nutrients and predation was best shown by changes in the distribution of body size. Both zooplankton and benthic communities showed complementary responses between large‐ and small‐bodied organisms. Differences in the physical structure of the environment (i.e., macrophytes) also produced significant changes in production and composition of both systems. The biomass production of the fish populations was clearly related to nutrient level. Both fish and invertebrate predators were size selective, but the fish had a much greater influence on the prey populations.
ENERGY FLOW IN A NATURAL POPULATION OF THE HERBIVOROUS GASTROPOD TEGULA FUNERRALIS1
Authors: Paine Robert T. 
Published: March 2010

The gastropod Tegula funebralis (A. Adams, 1855) is confined to the intertidal. At Mukkaw Bay, Washington, it typically occurs in patches of characteristic individual size structure. Various energy flow parameters have been determined for a high intertidal (+ 1.8 to +0.9 m) and a low intertidal (+0.6 to −0.15 m) subpopulation; these values were then combined in a 3:1 ratio to generate a composite population.Direct and indirect calorimetry and direct observation on the natural population suggest the following: Tegula spawns once per year; the dry weight‐shell diameter relationships for males and females can be expressed by a single regression; different caloric values characterize immature (5.2 kcal/ash‐free g), mature males (5.4), intermediately mature females (5.8), and fully mature females (6.1); rates of aquatic and aerial respiration are different (at 13.5C an average low intertidal individual, 211 mg dry wt, respires at a rate of 75 µl O2/hr in water and 43 µl/hr in air).The energy budget, in which ingestion was obtained by summation, suggests an assimilation efficiency of about 70%, a gross efficiency of growth of 16.7%, and an ecological efficiency of predators of 4.9%. Other efficiencies are discussed. In Tegula, 60% of energy transferred to other levels is to decomposers. Comparison of the rate of annual consumption by Tegula, 1,071 kcal m− 2 yr−1, and net primary production estimated by cropping, 1,167 kcal m−2 yr−1, indicate a near balance. Importation of primary production may be necessary to the maintenance of the rocky intertidal community at Mukkaw Bay.