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1.
The heat lability of succinic dehydrogenase, malic dehydrogenase and lactate dehydrogenase in cell-free extracts ofVibrio marinus MP-1 grown at 15C was compared for the tris buffer suspended enzymes and the NaCl suspended enzymes. The tris buffer suspended enzymes lost 50 percent activity at low thermal exposure between 5C and 27C. No activity was evident on thermal exposure between 32C and 39C. The enzyme extracts suspended in NaCl at 36 % were more heat stable, losing 50 percent activity after exposure between 16C and 40C. The enzymes lost all activity on thermal exposure between 33C and 42C in the presence of NaCl.  相似文献   

2.
The detailed oceanic structure was observed near the shoal Kokusho-sone (3000N, 12830E), which is located near the axis of the Kuroshio in the East China Sea. The detailed temperature cross-sections along the meridian 12830E, which passes over the shoal, strongly suggest that upwelling is forced along the north slope of the shoal. The behavior of the coastal waters near the Kuroshio front and of the cold water belt along the north-western side of the Kuroshio are also discussed.  相似文献   

3.
The heat balance of the upper ocean under a land and sea breeze was investigated based on observations of sea water temperature in the upper 300 m layer and heat flux across the sea surface at a fixed station in Sagami Bay (3510N, 13925E) during two periods of two days in August 1980 and three days in August 1981. During both periods, a typical land and sea breeze of 4–6 m sec–1 at maximum prevailed in the observation area. Large diurnal variation of sea surface temperature with a maximum peak around noon LST was observed during both periods (the daily value of the range was 0.9C and 2.5C in 1980, and 1.2C, 1.5C and 1.7C in 1981). It was found that these large temperature variations were caused by diurnal variation of the wind speed which dropped to 0–3 m sec–1 at noon when the strongest insolation (–270 Wm–2) penetrated the sea and at midnight in association with alternations of the land breeze and the sea breeze. On the other hand, vertical mixing of the sea water caused by the wind stress and/or convection due to cooling at night extended down only to the surface 10 m layer. Horizontal heat advection was negligibly small. Therefore the local time change of the heat content in the upper 10 m water column was affected mainly by the heat flux across the air-sea interface which was estimated from data on radiation fluxes measured directly on board and latent and sensible heat fluxes calculated by the aerodynamic bulk method. The water temperature below the 10 m layer also varied with time and the temperature variation in the thermocline (20–50 m depth) was frequently larger than that of the sea surface temperature. However, the variation in the upper 10 m layer was little influenced by that below the layer.  相似文献   

4.
The selectivity of amino acid assimilation by marine bacteria was examined using seven kinds of14C-amino acids and the acid hydrolysate of14C-labelled proteins. It was found that the net assimilation and respiration by marine bacteria followed MICHAELIS-MENTEN kinetics for all of amino acids used in our experiments. Maximum velocities of amino acids were 0.01 to 0.19g carbon/hour per 2×107 cells for net assimilation and less than 0.18g carbon/hour per 2×107 cells for respiration at 20C. The velocity of gross assimilation was found with the following order: phenylalanine>valine, glutamic acid>serine, arginine>tryptophan>glycine. The assimilation velocities of amino acids in these laboratory works showed almost the same order as those in field experiments. The assimilation velocity of an amino acid was influenced by coexisting another amino acids or glucose. The assimilation velocity in lower substrate range of amino acids was directly proportional to the number of bacterial cells in the range from 6×102 to 3×104 cells per ml. No linear relation between the assimilation velocity of amino acids and reciprocal of absolute temperature was found, but a marked bending was observed at 15 to 20C. The velocity at the optimum temperature was three to six times of that at 5C.  相似文献   

5.
The kinetic approach ofWright andHobbie (1966) was used to determine the heterotrophic potential of Antarctic waters. Variations with depth and geographical location are discussed. Temperature studies indicate the psychrophilic nature of the microbial population. In samples having environmental temperatures of approximately –1C, significant activities were recorded at the lowest incubation temperatures tested (–3C). Activities increased with increasing incubation temperatures up to +3C but were somewhat depressed at +10C and above. By testing a wide range of substrates, qualitative differences were noted in the microbial populations of different areas.Highest rates of uptake were found in the euphotic zone whereas Vmax values of samples from depths of 500 m and below were in most cases unmeasurable.Published as Technical Paper No. 4259, Oregon Agricultural Experiment Station.  相似文献   

6.
Diatomaceous silica, pretreated at various temperatures between 125 and 900C, was subjected to dissolution experiments and was analyzed using X-ray diffraction and infrared spectra. The diatomaceous silica preheated up to 900C, dissolved throughly into the solution of 2 per cent Na2CO3. On the digestion in the solution of 2 per cent Na2SO4, the dissolution of the silica decreased as the pretreating temperature increase; the degree of dissolution was different for various species. According to infrared absorption studies, the diatomaceous silica pretreated at a temperature below 500C preserved the reversibility of dehydration-rehydration almost qualitatively, while heating above 500C the samples lost the reversibility. Deformation of some kinks of diatomaceous silica pretreated above 500C, was percepted on infrared absorption spectra around 1,150 cm–1. The samples pretreated up to 900 C, however, did not show such an internal structural change as could be identified by the X-ray diffraction analysis. The content of Al and Fe in diatomaceous silica was low and have not much difference in quality among diatom species. From these experimental results, it was adequately understandable that diatomaceous silica, which has a metastable character, is variable in the silica forms among species and its process and rate of transformation of internal structure and/or surface sites by the treatment at given temperatures also show differences.  相似文献   

7.
The activity of photosynthesis and the contents of chlorophylla and pheo-pigments were compared in the samples of the intake and effluent seawater of Owase-Mita Thermal Power Plant and in the seawater samples in the Yoshimi Bay before and after heat treatment. At Owase-Mita Thermal Power Plant, after passage of sea water through the cooling system chlorophylla content reduced to about a half and pheo-pigment content doubled in August with high temperature (25–27C), but the contents of chlorophylla and pheo-pigments changed little in January with low temperature (16C); whereas the depression of photosynthetic activity after passing through the cooling system was 71–77 % in August and 31–46 % in January. In the laboratory experiments, the heat treatment at 34–43C for 7–8 sec., which resulted in temperature rise of 7–8C, gave the decrease of chlorophylla and an increase of pheo-pigments in August temperature (26.5C), but a slight decrease of chlorophylla and a slight increase of pheo-pigments in November at the initial temperature of 19.2C, while in January and December the samples with low initial temperature (11.6 and 10.8C) showed almost no change in the content of pigments; the decrease in photosynthetic activity was 32 % in August sample,ca. 11 % in November sample,ca. 15% in January and almost no change in December. It is concluded that the photosynthetic carbon assimilation of marine phytoplankton is suppressed by passing through the cooling system of a thermal power plant even at lower water temperature in winter, while the content of chlorophylla is affected very little at a temperature below 20C.  相似文献   

8.
Hydrographic observations between the Izu Peninsula and Oshima Island, Japan, in May 1982, showed upwelling around the tip of the Peninsula and possibly also in the lee of Oshima Island. The upwelling introduced water as cold as 18 C with nitrate concentrations of 3M to the surface. Temperature/salinity analyses indicated that the upwelled water was of Kuroshio characteristics. Slightly fresher water was advected out of Sagami Bay in a coastal counter current.Contribution number 470 from the Shimoda Marine Research Center, University of Tsukuba.  相似文献   

9.
Calcium-alkalinity relationship in the North Pacific   总被引：3，自引：0，他引：3  
The dissolution of calcium carbonate in deep ocean water causes variation in calcium concentration (Ca) and alkalinity (TA) in the ratio of one to two. The decomposition of organic matter generates nitric acid, phosphoric acid and sulfuric acid. A proton flux which is derived from this process also changes alkalinity. Using the variation in nitrate concentration (NO3) as an index of the proton flux, the relationship betweenCa,TA andNO3 is expressed asCa=0.5TA+0.63NO3 The values of Ca obtained from direct measurements in the North Pacific are in good agreement with the values estimated from this equation.  相似文献   

10.
Remarkable tidal currents associated with temperature fluctuations in the subsurface layer have been observed in Uchiura Bay. In order to study the characteristics of these tidal currents, we carried out current measurements in November 1972 and October 1974. It was confirmed from the first set of observations in 1972 that the tidal currents above and below the seasonal thermocline oscillate out of phase with each other and the tidal currents are associated with internal tides.In the second set of observations in 1974 not only current measurements but also serial BT lowerings were made. The phase of the thermocline displacements lagged behind the tidal currents by 81 for the semidiurnal constituent and by 83 for the diurnal constituent, and it is thus concluded that the internal tides in Uchiura Bay behave as standing waves.  相似文献   

11.
Phase velocity of semi-diurnal internal waves is determined from differences between phases at three stations which were situated to form a triangle in the vicinity of sta. T (29N, 135E). The wave phases are estimated from temporal variations in depths of isotherms obtained from serial measurements of vertical temperature profiles at these stations. The measurements were carried out in cooperative operation of two vessels, the R. V.Tansei-maru and theNojima, during the period from 30 July to 1 August 1965. Wave propagation with the speed of about 2 m/s in the direction from east to west is obtained as an average over several isotherms of temperature from 19C to 23C. The area of measurement is to the west of Izu-Mariana ridge and the distance from the ridge to the station is about 500 km, which would be about 5 times as large as the wave length of the internal waves under consideration, and so it is possible to suppose that the internal waves observed generated at the ridge and propagated to the area without being subjected to serious refraction, scattering, reflection and decay.  相似文献   

12.
Assessment was made of residual ratio of North Pacific Intermediate Water (NPIW) produced in subpolar region of the North Pacific using chlorofluorocarbons, CFC-11 and CFC-12 (CCl3F and CCl2F2), along 175°E. NPIW on density horizons less than 26.80 remained more than 80% north of 30°N. It was suggested that new NPIW laterally spreads over the northern North Pacific without hardly being diluted by the surroundings. For density horizons greater than 26.80 north of 30°N, NPIW remained less than 60%. The difference in the residual ratio between <26.80 and >26.80 north of 30°N suggests that NPIW is produced on density horizons less than 26.80, which contacts the atmosphere in the subpolar region, and that NPIW is diluted by upwelling deep water on density horizons greater than 26.80 in high latitude of the North Pacific. NPIW on a density horizon of 26.80 remained about 50% south of 30°N. The decrease in the horizontal distribution of the residual ratio of NPIW suggests that half the new NPIW produced in the subpolar region is laterally spread over the North Pacific with the southward movement of NPIW.  相似文献   

13.
Salinity, preformed phosphate and AOU distribution on the sigma-t surfaces of 26.8 and 27.3 of the central North Pacific Ocean, as well as the topography of these density surfaces, were studied. The direction of water flow suggested by the AOU distribution on these density surfaces was compared to that indicated by the acceleration potential contours on the t =125 cl/ton and t =80cl/ton surfaces drawn by Joseph L.Reid, Jr. The disagreements were explained in terms of mixing and possible gradients of primary production at the sea surface. On the 26.8 sigma-t surface a southward flow connecting the westward flow south of the Aleutian chain and the eastward flow farther south, between 175E and 180 is suggested by the AOU distribution but is not implied by the acceleration potential contours. If the circulation pattern at this density surface is similar to that at the sea surface, this southward flow is very likely to be real.  相似文献   

14.
Carbon and nitrogen stable isotope ratios (13C and 15N) of surface sediments were measured within Osaka Bay, in the Seto Inland Sea in Japan, in order to better understand the sedimentation processes operating on both terrestrial and marine organic matter in the Bay. The 13C and 15N of surface sediments in the estuary of the Yodo River were less than –23 and 5 respectively, but increased in the area up to about 10 km from the river mouth. At greater distances they became constant (giving 13C of about –20 and 15N about 6). It can be concluded that large amounts of terrestrial organic matter exist near the mouth of the Yodo River. Stable isotope ratios in the estuary of the Yodo River within 10 km of the river mouth were useful indicators allowing study of the movement of terrestrial organic matter. Deposition rates for total organic carbon (TOC) and total nitrogen (TN) over the whole of the Bay were estimated to be 63,100 ton C/year and 7,590 ton N/year, respectively. The deposition rate of terrestrial organic carbon was estimated to be 13,200 (range 2,000–21,500) ton C/year for the whole of Osaka Bay, and terrestrial organic carbon was estimated to be about 21% (range 3–34) of the TOC deposition rate. The ratio of the deposition rate of terrestrial organic carbon to the rate inflow of riverine TOC and particulate organic carbon (POC) were estimated to be 19% (range 3–31) and 76% (range 12–100), respectively.  相似文献   

15.
The formation of the spun up region by the withdrawal of water from a watergate located in the eastern boundary in a homogeneous ocean on a beta-plane at low Rossby number is presented. The spun up region penetrates only westward from the Watergate because of the special character of the generated Rossby waves. The growth rate and the final longitudinal length of the spun up region in the dissipative system is much affected by the watergate scale in the north-south direction.The relation with the experiment ofLong (1952) and the geophysical application are presented.  相似文献   

16.
Dependences have been determined which connect the parameters of the dispersion relation of the lowest mode of internal waves with the integral characteristics of the seasonal thermocline when 10 min30 min, 20 mh150 m, and 0·4 m2/s2 Q5·2 m2/s2.Translated by Mikhail M. Trufanov.  相似文献   

17.
Regeneration of silicate in the Japan Sea, an example of semi-closed sea, was studied. In the Japan Sea Proper Water the apparent regenerative ratio of the nutrients was determined to be:O C N P Si=–289 (116)14.3181.It was assumed that the dissolved silicate present in sea water is grouped into three fractions; 1)preformed silicate of conservative nature, 2)oxidative silicate which dissolves in oxidation process of organisms with consumption of oxygen, and 3)non-oxidative silicate which dissolves without oxygen consumption. The dissolution rate ofnon-oxidative silicate in the Japan Sea Proper Water was estimated to be 0.07g-at. Si/l/yr from the data ofAOU values and assumed rates of oxygen consumption. This dissolution rate ofnon-oxidative silicate agreed with that obtained in the deep Pacific by the vertical advection diffusion model byKido andNishimura (1972).  相似文献   

18.
The bacterial populations of mangrove swamps of Killai backwaters (11°21–11°29N, 79°46–79°50E, South India) were studied during August 1968 (Pre monsoon period) and December (post monsoon period). The presence of these groups such as agar digesters, algin digesters, cellulose digesters, sulphate reducers etc., bring about transformation of organic matter in the mangrove swamps. The presence of denitrifiers in mangrove swamps and in association with the molluscs may bring about the precipitation of calcium carbonate by removing the acid radicals such as sulphate and nitrite, increasing alkalinity. The luminiscent bacteria such asVibrio andAeromonas were also isolated in mangrove swamps of Killai backwaters. The iron bacteria likeLeptothrix sp. andGallionella sp. were also isolated from mangrove swamps of Killai backwaters.  相似文献   

19.
Information on the distribution of dissolved Folin phenol active substances (FPAS) such as tannin and lignin in the seawater along the west coast of India is provided. Notable amounts of FPAS (surface concentrations: 80 g/l to 147 g/l and bottom concentrations: 80 g/l to 116 g/l) were detected in the seawater along the coast. The distribution pattern brings about a general depth-wise decrease. A seaward decrease was observed in the southern stations whereas reverse was the case in northern stations. A significant negative correlation was observed between FPAS concentration and dissolved oxygen in sub-surface samples. The appreciable amounts of FPAS detected in the coastal waters indicate the presence of organic matter principally originating from terrestrial (upland and coastal marsh) ecosystems in the marine environment. In this context, they may be used as tracers to determine the fate of coastalborn dissolved organic matter in the ocean and to determine directly the relationship between allochthonous and autochthonous organic matter.  相似文献   

20.
From July to November, the thermocline which has strong temperature gradient (0.7C m–1) is formed in the bottom water of Beppu Bay, and it prevents the downward mixing of surface water. This has caused the bottom water of the basin to become depleted in oxygen, and in November the bottom water below about 60 m depth becomes anoxic. Accordingly manganese and iron are reduced and more soluble under the anoxic condition, those concentrations are high relative to surface water, and the maximums are 1,240g l–1 and 80g l–1. Under the anoxic condition, the flux of dissolved manganese from the sediment is about 10g cm–2 day–1.  相似文献   

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