Showing papers in "Limnology and Oceanography in 1962"

Environmental control of photosynthesis in the sea

Abstract: A theoretical equation for the photosynthesis-light relation is developed which includes the effects of inhibition in intense light. Assuming 1) that phytoplankton adapts to seasonal light changes and 2) that nutrient deficiency affects the carbon:chlorophyll ratio of natural phytoplankton populations, equations arc derived which determine photosynthesis per unit chlorophyll and the carbon: chlorophyll ratio as functions of incident radiation and nutrient concentration. These equations appear to describe the main trends in the open North Sea and in a sea loch on the west of Scotland. The photosynthesis-chlorophyll relation also describes the main trends of observations in the Sargasso. For a very shallow turbid area, the agreement was not so good.

Measurement of visible light absorption by particulate matter in the ocean1

Abstract: For the measurement of visible light absorption by particles in sea water, optical arrangements have been devised where scattered light is integrated and the photodetector “sees” mostly diffused light. High spectral resolution has been obtained by removing particulate matter from sea water using a membrane filter and scanning the filter against an unused filter as the reference blank in the Cary spectrophotometer. In this fashion spectral curves for particulate matter in the oceans have been obtained. These curves show pigment banding in the upper 100 m of water characteristic of absorption by chloroplastic pigments. Below this depth the absorption of particulate matter is characterized by a gradual increasing attenuation from long to short wavelengths. Optical density ratios of chloroplastic pigment bands seen in the particulate matter of the upper 100 m suggest the presence of absorbing components not generally seen in algal cultures. Differential filtration through graded filter sizes (5.0 µ-0.3 µ) followed by the spectral scanning of filters, shows that practically all of the chloroplastic pigments are retained by the 5.0 µ filter. Particles passing this filter show little selective attenuation of visible wavelengths. The nature of sea water particulate matter is discussed in terms of its absorbing characteristics as well as the significance to phytoplankton ecology.

Role of detritus in the productivity of a rock‐outcrop community in a piedmont stream

Abstract: A rock outcrop community in a typical southern Piedmont stream was studied to determine its trophic structure and productivity. Poclostemum ceratophyllum was the primary producer component of the community and also provided a place of attachment and shelter for a rhcophilic fauna consisting largely of insects. The primary consumer organisms derived 66% of their energy from allochthonous organic matter consisting largely of leaf material. Productivity by phytoplankton in the river water was insignificant as was rcspiration in the shifting sand bottom. The river behaved as a heterotrophic stream because of suspended organic detritus in the water. A higher and more variable quantity of particulate detritus was present in the water during summer than winter. This seasonal diffcrcnce was attributed to stream dischargostrcam bed relationships and a more rapid decomposition of organic fragments at higher summer temperatures. The net annual productivities, determined by the cropping method, in Cal/cm2 for trophic groups were: Podostemum 434, filter fccdcrs 16.8, herbivores 6.51, detritus feeders 1.68, herbivore and detritus feeders 2.78 (total primary consumer 27.8), and carnivore 3.66. The turnover of biomass increased with increasin$ productivity by individual spccics but this relationship dots not hold true for all communities. A comparison of trophic level production efficiencies and productivities in several communities suggests there are selfregulating mechanisms in natural communities which function between producer and consumer groups. Community stability is an important factor for the realization of maximum productivity in flowing water environments. A theory of stream succession has been proposed which is based on the graded stream

A study of the intertidal fauna of barnstable harbor, massachusetts1

Abstract: An intensive investigation of 6 localities on the intertidal flats of Barnstable Harbor, Mass., was undertaken during the summer of 1959. The number of animals ranged 7,000– 355,000/m2. The total dry weight varied from 17.6–60.2 g/m2. A less detailed study was carried out on the same stations during the summer of 1960. A total of 82 species were collected during the 2-year period. Stomach contents of 234 individuals representing 36 species showed that many of the forms considered to be carnivorous are, in reality, omnivores obtaining most of their food as deposit-feeders. This explains why many of these species are present in such large numbers. With the exception of molluscs and crustaceans, the supposed carnivores, selective, and non-selective deposit-feeders can each be divided into three groups with respect to stomach contents: 1) Smaller species with only diatoms, detritus, and sand grains in the gut; 2) Intermediate-sized species with these components plus fragments of macroalgae and occasional animal remains; 3) Larger species with conspicuous animal remains in the gut in addition to all the other components. Despite the fact that the sediment at 5 of the stations consisted almost entirely of fine sand with very little organic matter, most of the biomass (78%) was made up of animals that are primarily deposit-feeders. The presence or absence of large populations of deposit-feeders in sandy sediments was correlated with the stabiltiy of the sediment surface; in unstable sediments, as indicated by ripple marks, the standing crops were small; in stable sediments where the ripple marks were absent, dense concentrations of benthic diatoms and dinoflagellates were found which provide the major food source for the large biomass of deposit-feeders. The chlorophyll readings obtained from the sediments were about intermediate between the highest values reported for sea water and a rich terrestrial environment. Observations were made on the natural history of the three dominant species: Gemma gemma, Glymenella torquata, and Glycera dibranchiata.

On circulation, phosphate-phosphorus content, and zooplankton volumes in the upper part of the pacific ocean1

Abstract: The circulation of the Pacific Ocean may be considered to consist of two high-latitude cyclonic gyres, two subtropical anticyclonic gyres, and a series of subequatorial zonal flows in alternate directions. The phosphate-phosphorus at the surface is related to the surface divergence and is high in the cyclones, low in the anticyclones, and high in regions of coastal and equatorial upwelling. The PO4-P at 100 m is related to the depth of the pycnocline and is also high in the cyclones and low in the anticyclones, and high at the equator and at the poleward edges of the equatorial countercurrents. The zooplankton volume is distributed very much as is the PO4-P, particularly that at 100 m. It is also low in the anticyclones and high in the cyclones, at the equator and at the poleward edges of the equatorial countercurrents. At the center of the subarctic cyclone, however, zooplankton is only moderate, but PO4-P concentration is high both at the surface and at 100 m. It is suggested that the surface divergence is too rapid for zooplankton to accumulate in the center of the cyclone, even though reproduction and growth may be prolific. In the California Current zooplankton volume appears to vary inversely with temperature, and an area of minimum volume and maximum temperature is found near the tip of Baja California. It is speculated that this indicates a change from subarctic to subequatorial species. This, and the close relation of the plankton volume to the system of gyres, suggests that the gyres may represent the principal plankton communities.

Primary Production in Fishponds and its Application to Fertilization Experiments

Abstract: Primary production was determined in fertilized and unfertilized fishponds in Israel by the “light and dark bottle” oxygen method. In the unfertilized ponds it was in summer 138–190 mg C/m2/hr; in the fertilized ponds it was 4 to 5 times higher. There was a sharp decrease of production with depth and in most cases the compensation layer in the fertilized ponds was at the depth of only 40 cm. Chlorophyll a concentration was high reaching a maximum value of 212.3 mg/m3 in the fertilized ponds. Production per unit of chlorophyll and its variations with season and fertilization rate is discussed. Fertilization of fishponds with excessive amounts of fertilizers increases production in the upper layers of the water where favorable light conditions exist, but decreases production in the lower layers, where overshading by the plankton causes decreased light penetration. The effect of excessive doses of fertilizers may thus cause a lowering of production per unit area.

Observations on the biology of the american lobster, homarus americanus

Abstract: American lobsters (Homarus americanus) have been hatched and reared at the Massachusetts State Lobster Hatchery, Oak Bluffs, Mass., since 1951. Individual lobsters have been held for as long as 10 years. Records have been maintained on seasonal occurrence of hatching, duration of the larval period, occurrence of molting with age and season, and rates of growth. The peak in hatching intensity occurs in late June or early July when water temperatures approximate 20°C. Time required for larvae to attain the 4th stage appears to be inversely related to temperature above 18°C, with less evidence of temperature-dependence below this level. Molting frequency declines with age; lobsters molt approximately 9 times during their first growing season but no more than once annually by their sixth growing season. Molting occurs most frequently in early summer and again in early fall. Growth rates indicate that a period of 5 years from date of hatching is required for a lobster to attain legal marketable size—3 3/16 in. carapace length—in Massachusetts. Percentage increase in length per molt declines with age.

A LIMNOLOGICAL RECONNAISSANCE IN THE AREA OF McMURDO SOUND, ANTARCTICA1

Abstract: During the Antarctic summer of 1960–61, limnological data were collected from a series of meltwater ponds and permanently ice-covered lakes in the area of McMurdo Sound, Antarctica (77°51′ S, 166°37′ E). All ponds were basic and more saline than typical fresh-water lakes. Primary production, measured in two ponds by the “light and dark bottle” technique, varied from 326 to 1008 mgC/m3/day. High intensity of light inhibited photosynthesis in shallow water. Lake Bonney in Taylor Dry Valley and Lake Vanda in Wright Valley lie in a large ice-free area in South Victoria Land on the west side of McMurdo Sound. Each lake is covered with 3.4–4.2 m of permanent ice and is meromictic. The mixolimnion of Lake Bonney varied from 0.3°–8°C; the monomolimnion was below 0°C. The mixolimnion of Lake Vanda varied from 0.7°–9.6°C; the monomolimnion was warmed to 22°C. The lakes are probably warmed geothermally. No zooplankton was found in any of the lakes, but 7 genera of Ciliata, 4 of Rotifera, and one each of Nematoda, Turbellaria, and Tardigrada were collected from the littoral fauna of the meltwater ponds and around the edges of Lakes Bonney and Vanda.

Productivity relations in carboy microcosms1

Abstract: Measurements of gross photosynthesis; respiration, rate of net oxygen diffusion, and organic storage are reported for 7 microcosms maintained over periods of 5 to 7 months. Average rates of gross photosynthesis ranged from 0.86 to 1.69 g Oz/m2/day and were related to the amounts of inorganic nutrients added. Average final organic storage was equal to 35.6% of gross photosynthesis. Assumed photosynthetic quotients between 0.88 and 1.03 allowed the construction of oxygen budgets in which the total product of gross photosynthesis was accounted for. Some problems of establishing productive microcosms representing natural situations are also discussed.

Further relations between primary production, chlorophyll, and particulate carbon

Abstract: The productivity of a sea loch, Loch Nevis, on the west of Scotland, is cstimatcd from nitrate and phosphate data. These results show that even though the nitrate:phosphatc ratio in the water is ncvcr more than 10: 1 (by atoms ) and is less than 1: 1 in the euphotic zone in summer, the assimilation and regeneration ratio of these elcmcnts is always close to the “normal” ratio of 16:l. Chlorophyll n and particulate organic carbon data are used to study the possible carbon:chlorophyll ratios in the plants. During the summer the ratio is calculated to be 74:l and the remaining data suggest lower values for spring and autumn. For a different area, the northern North Sea, carbon and chlorophyll samples during the spring flowering provide an estimated value of 23: 1 for the carbon:chlorophyll ratio under very favorable conditions for growth. The possible causes of the differences bctwccn the carbon:chlorophyll ratios for Loch Nevis and the northern North Sea are discussed.

Factors influencing the mineralogy of carbonate sediments1

Abstract: The mineralogy of carbonate sediments from Campeche Bank and Bermuda has been studied by use of X-ray diffraction techniques. The sediment mineralogy appears to be mainly controlled by the skeletal mineralogy and size of organisms living locally. Selective physical destruction and transport and selective solution of more soluble skeletal elements appear to exert an influence on sediment mineralogy. Reef and near-reef sediments contain the largest concentrations of high-magnesium calcite, largely due to the presence of coralline algae such as Lithothamnium. Lagoonal sediments contain the most aragonite, and also contain abundant fragments of the green algae, Halimeda. Shelf, slope, and deep-water carbonates are rich in low-magnesium calcite, probably due to the presence of planktonic Foraminifera and algae. The effects of non-biological processes on sediment mineralogy can be seen in the distribution of mineralogies among the different size fractions of the sediment. The most prominent feature of this is the regular increase in mineral stability—and associated decrease in mineral solubility—from the coarse to the fine fractions of sediments from a wide range of environments. It appears that in some areas the more soluble mineralogies are dissolved from the fine fractions of the sediments.

Nitrogen metabolism in lakes ii. role of nitrogen fixation in sanctuary lake, pennsylvania1

Abstract: A study of the rates of nitrogen fixation using N1” as a tracer was made in Sanctuary Lake, Pennsylvania. The rates of fixation in the lake were found to be considerable during the summer and appeared to be correlated with the presence of a dense population of Anabaena. Laboratory cxpcriments supported the idea that photosynthetic organisms were responsible since a strong correlation with light was found.

Nitrogen metabolism in lakes i. measurement of nitrogen fixation with n151

Abstract: A method for measuring the rates of nitrogen fixation in samples of lake water using N15 as a tracer is described, and a detailed description of glassware required is provided. The nitrogen present in the water is removed by flushing with Hc-O mixture and then replaced by the labeled nitrogen. After incubation and treatment, the isotope ratio in the organic material is determined on a mass spectrometer. Analyses of lake water and (NH4) SO4 as isotope ratio blanks are described and a resume of statistical data from these analyses is presented.

Ecology and taxonomy of yeasts isolated from various marine substrates1

Abstract: Yeasts wcrc observed to be of common occurrence in subtropical marine waters and scdimcnts and with indwelling plants and anilnals. The most prevalent types prcscnt in all environments were oxidative, asporogcnous forms which expressed a growth requircmcnt for one or more vitamins. Certain distinctive metabolic attributes of yeasts were associated with environmental distribution. The incidental yeast flora on marine vegetation was uniformly low in number and consistent with the spccics isolated from surrounding waters and scdimcnts. The species found within the intestinal contents of fish appcarcd to be of transitory nature and restricted in population density. Yeasts have been found in significant numbers in the waters of those oceans and seas that have been systematically studied. The enumeration and taxonomy of yeasts in Atlantic subtropical marine waters and sediments has been reported by Fell, et nl. ( 1960) wherein the influence of terrestrial run-off on the yeast populations of estuarine areas and the presence of yeasts in planktonic masses and benthic sediments was established. As a further and continuing study of the ecology and systcmaties of marine fungi, selected aquatic habitats were examined intensively for the occurrence of yeasts to establish possible sites of active growth and reproduction of these microorganisms. In this work, quantitative and qualitative studies of the indigenous yeast flora isolated from diverse marine waters, sediments, and associated plants and animals were undertaken. MATERIALS AND Ml~ITIODS

Heat flux in lake mendota1

Abstract: The physical processes of heat transfer at the lake’s surface and the internal heat flux are studied for ‘“average” Lake Mendota and for 1958–59 The surface heat budget is determined quantitatively Details of the internal fluxes of the heat supplied or lost at the surface are discussed, with emphasis on the effects of wind stirring and hydrostatic stability It is shown that a well-known solution to Fourier’s heat conduction equation suffices to describe many of the features of the internal temperature range and heat flux when an effective thermal diffusivity is introduced The solution is further used to demonstrate that the internal seiche along the thermocline causing heat flow in bottom sediments may account for 40% of the heat transfer to the hypolimnion

Environmental characteristics of raritan bay, a polluted estuary1

Abstract: Temperature, salinity, dissolved 02, PO,-P, and NO:,-N in Raritan Hay, N. J. vvere detcrmined over a 16-month period. Each reflects the circulation pattern in which sea water floods along the northern shore, enters a region of mixing with river dixhargc in the head of the bay, and then ebbs out along the southern shore. At the mouth of the bay, salinity was higher on the northern than on the southern side. The mean annual monthly difference at the surface was 1.272,; departures from the mean were related to river flow. Surface and bottom dissolved O2 content were minimal in August arid Ilighcxt during winter. Low concentrations occurred in the Raritan River, especially. during the summer preceding operation of a trunk sewer. The primary source of NOJ-N was outflow from the Raritan River. Prior to operation of a trunk sewer, the river may have discharged significant quantities of PO,-1’ into the bay. Throughout spring and summer, PO, concentrations rose and NO:{ decreased. It is pohtulated that the resultant low N:P ratio was partially due to an efficient nutrient regeneration mechanism that favored the rate of P renewal. A combination of rich nutrient supplies arising from natural and domestic soruces, plrls a sluggish circulation, efficient nutrient regeneration mechanism, and scarcity of nnrcroscopic algae combine to form an estuarine environment capable of supporting estrernely dcbnsc pl&kton populations.

Determination of phosphate in water after storage in polyethylene1

Abstract: The changes in phosphate concentration which take place when lake water is stored in polyethyleno bottles have been studied. The reduction in phosphate concentration which occurs is attributed to bacterial action and not to absorption of phosphate by the polyethylene. Appreciable changes in phosphate concentration can be avoided by collecting the sample in a polyethylene bottle which has been treated with a solution of iodine in potassium iodide solution.

Activation analysis of manganese and zinc in sea water1

Abstract: The use of activation analysis for the determination of microgram quantities of Mn and Zn in sea water was investigated. Total Mn and Zn were separated from the other elements of sea water by coprecipitation with iron and hydroxide, and divalent Mn and Zn were separated by extraction with diethyldithiocarbamate. Analyses were made from samples of water from different locations and depths of the North Pacific, Atlantic, and the Gulf of Mexico. Evidence indicated a substantial portion of Mn and Zn is held in sea water in a non-dialyzable and non-extractable form. (Public Health Eng. Abstr., 42: No. 11, Nov. 1962)

Occurrence of ammonia in sargasso sea waters and in rain water at bermuda1

Abstract: A year-around record of the concentration of ammonia-nitrogen occurring in the Sargasso Sea off Bermuda is given. It is shown that ammonia-nitrogen is present in significantly greater quantities than nitrate-nitrogen down to 100 m. In addition it is postulated that a large fraction of naturally occurring ammonia is contributed to surface waters by rainfall. Observations by Cooper (1937) in the English Channel and by Phifer and Thompson (1937) in Friday Harbor, Washington, have shown definite seasonal cycles in the concentration of ammonia, nitrate, and nitrite. In general, these data show that during and after the period of greatest plankton development, there is a rise in ammonia, followed by one in nitrite and then nitrate. This progression is considered typical of the regeneration cycle of nitrogen compounds in the ocean. The end product of this cycle is nitrate and it is uncommon that large amounts of ammonia or nitrite are found in nature. l Contribution No. 317 from the Bermuda Biological Station under Contract AT( 30-l ) -2646 with the Atomic Energy Commission. In August 1960, routine measurements of ammonia were initiated at Bermuda to supplement a program involving the study of nutrients in relation to the production of phytoplankton. The results of all analyses completed to date are given in Table 1. These show values on the average higher in the surface than in deep waters with a variable degree of scatter at any given depth. It is probable that this scatter does not represent analytical error, but rather variation due to adsorption of ammonia on particulate matter. The estimated accurzy of the method used (Krusc and Mellon 1952) is -t0.2 pg A/L. The striking fact borne out here is that the ammonia fraction of the inorganic nitrogen is roughly 24 times the concentraTABLE 1. The concentration of ammonia nitrogen in Sargasso Sea waters July 1960-June 1961 (pgA/L) --__~-~ ~. _-~~ -196

So‐called anecdysis in balanus balanoides and the effect of breeding upon the growth of the calcareous shell of some common barnacles

Abstract: The moulting frcqucncy when IUznus bahoitles is brought into the laboratory and fed at a constant tcmpcrature is roughly the same throughout the year and there is no cvidencc of a major cndogcnous anccdysis comparable with that in many other crustaceans. Variations in the moulting frequency under normal seasonal conditions are largely detcrmincd by the metabolic reserves, available food, and tcmperaturc, all of which are at a low lcvcl in a borco-arctic winter. There is, howcvcr, a short period immediately following the laying clown of the egg-masses when the moulting frequency is grossly reduced and evidence is presented that this is largely due to a debilitated condition which results from the discharge of reproductive material; this in turn lcads to an uptake of water with a subsequent reduction of feeding activity. For this period the term reproductive anecdysis is suggested. The reduced &ding activity during reproductive anccdysis will largely explain the lower growth rate achieved by breeding animals compared with that of non-breeding animals.

Activation analyses of vanadium, arsenic, molybdenum, tungsten, rhenium, and gold in marine organisms1

Abstract: Activation analyses have been carried out for 6 trace elements—vanadium, arsenic, molybdenum, tungsten, rhenium, and gold—in the ashes of several different types of marine organisms. Radiochemical procedures coupled with gamma-ray measurement permitted unambiguous determination of submicrogram amounts of these elements. No reagent blank corrections were needed. Experimental sensitivities for each element are given.

Phytoplankton in the southwestern sargasso sea and north equatorial current, february 19611

Abstract: In a l,OOO-mile section in the tropical Atlantic, flagellate species, with one exception, tended to be uniformly distributed, but diatoms, for the most part, were more numerous toward the southern end of the section. This change was associated with an intensification of stratification of the upper 100 m. The relative ability of flagellates and diatoms to react to varying growth conditions, in turn dependent on hydrography, is discussed.

Observations on the food of nephtys

Abstract: Analyses of gut contents of Nephtys &rosa and N. hombergi show these species to be carnivores. The density of both intertidal and sublittoral populations of these and other species and the organic content of soils in which they occur, as well as other factors, are all consistent with the view that Nephtys is usually a carnivore and not a non-selective detritus feeder, Those sublittoral populations of N. incisa on the American Atlantic coast, which have been shown to feed on detritus are exceptional for the species and the family.

Principal diatoms of major waterways of the united states

Abstract: The National Water Quality Network was established by the Public Health Service to secure data on water quality of the major waterways of the United States. This paper has been made possible by the aquatic biology studies carried on through the Network, which include radiological, bacteriological, organic, and inorganic chemical and physical parameters. As of 1 July, 1961, water samples for plankton analysis were being collected semimonthly from 86 stations. These samples are shipped to the PHS laboratory of the National Water Quality Network at Cincinnati where counts of different kinds of organisms are made to determine their proportional abundance, their seasonal variations, and differences in population densities at various stations. The determination of species composition of diatoms by proportional counting became a routine function after the more abundant and widely distributcd species cncountercd at stations of this Network had hecn determined. Grateful acknowledgment is given to Dr Charles W. Reimer, assistant curator of limnology, Academy of Natural Sciences of Philadelphia, and Dr Matthew Hohn, Central Michigan University, for identifying some of the species of diatoms, and to Drs C. M. Tarzwell and C. M. Palmer of the R. A. Taft Sanitary Engineering Center, who were in charge of the plankton program when it was initiated in 1957.

Temperature correction in conductivity measurements1

Abstract: Electrical conductivity has been widely used in freshwater rcscarch but usual methods employed by limnologists for converting measurements to conductance at a given temperature have not given uniformly accurate results. The temperature coefficient used to adjust conductivity of natural waters to a given temperature varies depending on the kinds and concentrations of electrolytes, the temperature at the time of measurement, and the temperature to which measurcmcnts are being adjusted. The tempcraturc coefficient was found to differ for various lake and stream waters, and showed seasonal changes. High precision can be obtained only by determining temperature coefficients for each water studied. Mean temperature coefficients are given for various temperature ranges that may be used where less precision is required.