Showing papers in "Japanese Journal of Limnology (rikusuigaku Zasshi) in 1983"
TL;DR: The intention of the present study is to examine the rule on the oxygen uptake due to specific dynamic action of carp, for the information it may provide on the mechanism of specific Dynamic Action, and to find out whether the rate increases with time.
Abstract: The intention of the present study is to examine the rule on the oxygen uptake due to specific dynamic action of carp, for the information it may provide on the mechanism of specific dynamic action. The oxygen uptake of fish fed diets was measured continuously. The metabolic rate due to specific dynamic action appeared for 14 to 18 hours at 25°C. The amount of oxygen uptake due to specific dynamic action is composed of a part that is proportional to the ration size and a constant part. The relation between the oxygen uptake due to specific dynamic action (QSDA, ml) and the ration size (x, g) is given by the formula QSDA=α·x+b. Because of this relation, when the ration size is small, oxygen uptake shows changes close to the changes of b, which is higher at 0-2 and 8-10 hours. As the ration size increases, the peak of the rate increases with time, and the whole movement of oxygen uptake becomes dominated by the higher α at 2-8 hours. Also, a is affected by the composition of the diets and is much higher for a high protein diet. The value of a was in the range of 20 to 60 ml·g-1, and the value of b was approximately 50 ml.
27 citations
TL;DR: Shimoda et al. as discussed by the authors found that the amount of chlorophyll-a in the euphotic layer was low during the stagnation period, and high during the circulation period.
Abstract: Lake Fukami-ike is a small lake having a maximum depth of 8.5m, and is well protected from the wind. Lake water stratified from March to October and circulated from November to Mardi. Anoxic condition prevailed below 4-5 in depth from April to October. From 1956 to 1957, SHIMODAIRA found that the amount of chlorophyll-a in the euphotic layer was low during the stagnation period, and high during the circulation period. The same pattern of seasonal change in chlorophyll-a was observed in this study. It was suggested that such a seasonal change in chlorophyll-a amount might be caused by 1) the interruption of upwards nutrient transportation from the tropholytic layer due to a distinct stagnation of water and the consumption of nutrients by photosynthetic sulfur bacteria growing near the top of anoxic layer in summer, and 2) the sequential change of circulation and stagnation of water which gives a favorable condition for phytoplankton growth in winter.
20 citations
20 citations
17 citations
TL;DR: In this paper, the authors developed a numerical index (RPID) to assess the river pollution by using a new diatom community index (NDCI) based on the specific composition of epilithic diatom communities.
Abstract: WATANABE (1982) developed an equation to obtain the river pollution index (RPIB) by which he tried to assess the general state of river pollution. This equation is based upon the water quality chart obtained from biological assessment. The water quality chart, however, only indicates the distribution of area with different degrees of water pollution (from 4 to 6 degrees). Accordingly WATANABE (1981) developed the diatom community index (DCI) based on the specific composition of epilithic diatom communities at each station. This index is based on his idea that the degree of water pollution in rivers actually changes gradually and continuously and that they, therefore, can not be classified into some definite areas with numerical degrees in itself. In this study we developed a numerical index (RPID) to assess the river pollution by using a new diatom community index (NDCI) based on the specific composition of epilithic diatom communities.
11 citations
11 citations
TL;DR: In summer, the japonicus group of Goerodes changes from the the upper to the lower stream with overlapping zones in the following sequence : G. complicatus→ G. nukabiraensis→G.
Abstract: In summer, the japonicus group of Goerodes changes from the the upper to the lower stream with overlapping zones in the following sequence : G. complicatus→G. nukabiraensis→G. bipertitus→G. japonicus. In winter, G. satoi is found both upstream and downstream and its lower limit of distribution is lower than for G. complicates. The number of G. nukabiraensis generations is presumed to be three in two years in Hokkaido. And the annual life cycles of G. bipertitus and G. japonicus are as in G. nukabiraensis.
9 citations
TL;DR: In this article, measurements of rainfall, outflow and soil water movement were made in order to clarify a mechanism of groundwater recharge caused by a heavy rainfall in Kanto loam soil, and more than two hours in sand.
Abstract: Observations were carried out using a couple of monolith lysimeters with a water table at 145 cm below the ground surface. Measurements of rainfall, outflow and soil water movement were made in order to clarify a mechanism of groundwater recharge caused by a heavy rainfall. The lysimeters were packed with sand 0.38 mm in median grain diameter and Kanto loam originating from volcanic ash soil whose heights of capillary rise are about 45 cm and larger than 125 cm, respectively.Groundwater recharge in the Kanto loam soil begins usually to increase and decrease earlier than in sand. The time required until the beginning of the increase in outflow after the peak of a rainfall intensity is an hour or two in Kanto loam soil, and more than two hours in sand. During the observation period of about one year, outflow from the Kanto loam soil stopped for 34 days and that from the sand for 3 days. These data indicate that groundwater recharge occurs as soon as the wetting front reaches the upper boundary of the capillary water zone, soil water in the suspended water zone is drained slowly and that in the capillary water zone quickly until a water equilibrium is established.
7 citations
TL;DR: Two experiments were carried out to estimate thegross efficiency and the conversion efficiency of phytoplankton in the growth of silver carp, Hypophthalmichthys molitrix, and the results showed the gross efficiency figures of 15% for Anabaena, 11% for diatoms and 1.5% for Microcystis.
Abstract: Two experiments were carried out to estimate the gross efficiency and the conversion efficiency of phytoplankton in the growth of silver carp, Hypophthalmichthys molitrix. One involved the determination of the growth rates of silver carp at each respective bloom of different algal species in Lake Kasumigaura, and the other, the estimation of food intake by silver carp. The results showed the gross efficiency figures of 15% for Anabaena, 11% for diatoms and 1.5% for Microcystis. Considering the digestive efficiency, the conversion efficiency figures of 19% were obtained for diatoms and 4.5% for Microcystis.
7 citations
TL;DR: The fact that both homologues identical to B-3 or B-8 were found in oxic layers suggests that these denitrifiers might grow by aerobic respiration rather than denitrification because of the oxidative nature of their metabolism.
Abstract: Six antisera were prepared against 6 denitrifying bacteria isolated from Lake Kizaki (classified into 2 strains of the Pseudomonas fluorescent group, 2 of the Pseudomonas achromogenic group, 1 of the Pseudomonas group producing no acid and 1 of the Alcaligenes-Achromobacter group).Using both serological agglutinate reaction and immunofluorescent staining method, 60 isolates and 194 enrichment culture tubes for the MPN estimate of denitrifiers were tested for serological identity with each of the antigen denitrifiers. Fifteen strains among 60 isolates and denitrifiers in 25 tubes among 194 MPN counting tubes were identical to one or another of the 6 antigen denitrifiers. Seasonal and vertical distributions of these 40 identified denitrifying bacteria in the lake were described.Homologues of two strains of denitrifiers were most frequently found in L. Kizaki (68% or 27/40). One of them (Strain B-8, belonging to Pseudomonas fluorescent group) was found only in the circulation period or in the water layer where the dissolved oxygen concentration was about 10 mg·l-1. The other (Strain B-3, belonging to Pseudomonas achromogenic group) was found only in the stratification period or in the water layer where the dissolved oxygen concentration was above 5 mg·l-1.The fact that both homologues identical to B-3 or B-8 were found in oxic layers suggests that these denitrifiers might grow by aerobic respiration rather than denitrification because of the oxidative nature of their metabolism. However, from the standpoint of denitrifying activity, it is noteworthy that the only exception to the known distribution of these denitrifiers was found in the anoxic hypolimnion in November where many different denitrifiers were found.
6 citations
TL;DR: The food selection of a herbivorous ciliated protozoa, Condylostoma vorticella (Ehrenberg) was examined in November 1980 in Takahamairi Bay of Lake Kasumigaura, using IVLEV'S (1955) electivity index.
Abstract: The food selection of a herbivorous ciliated protozoa, Condylostoma vorticella (Ehrenberg) was examined in November 1980 in Takahamairi Bay of Lake Kasumigaura, using IVLEV'S (1955) electivity index. This ciliated protozoa selectively fed on Synechococcus, Kirchneriella, Dictyosphaerium, Coscinodiscus, Cryptomonas, Chlamydomonas, and Gomphosphaeria, but rejected Closterium, Phormidium, Synedra, Tetrastrum, Dactylococcopsis, Scenedesmus, Aphanizomenon, Melosira, and Micractinium. The size and shape of algae were significant in the food selection, but the taxonomical groups were insignificant. The ciliate fed efficiently on food particles between 15 m and 40 m in size, but not filamentous and spindlelike algae or algae with long spines. Colonies of Microcystis found most abundantly in this lake were preferably ingested by the ciliate. This ciliated protozoa is likely a significant link in the food chain between Microcystis and crustacean zooplankton.
TL;DR: In this paper, the relationship between the occurrence of aquatic macrophytes and the chemical nature of the water was investigated along with some major elements (pH and concentrations of Ca, K and Mg) in the water of 65 randomly selected reservoirs.
Abstract: To clarify the relationship between the occurrence of aquatic macrophytes and the chemical nature of the water, the flora of aquatic macrophytes grown in 122 irrigation reservoirs in Tokai District was investigated along with some major elements (pH and concentrations of Ca, K and Mg) in the water of 65 randomly selected reservoirs. By dividing the irrigation reservoirs into three altitudinal locations (plain, lower hillside and higher hillside), it was revealed that 23 species of the aquatic macrophytes (exclusive of two omnipresent species, Phragmites communis and Zizania latifolia) inhabiting these reservoirs could be classified into six groups. Since both pH and the concentrations of the three elements in the water gradually lowered with the higher altitude of reservoirs, it was supposed that the flora of each reservoir was considerably influenced by some elements of its water, and the latter must in turn have been affected by the geographical feature of the basin in which the reservoirs were located.
TL;DR: In this paper, six different extraction techniques for copper, lead and cadmium were studied in Nagara River sediments in Gifu Prefecture, Japan, and the comparison of the extraction techniques was conducted on the basis of the heavy metal contents originating from pollution, which was estimated by subtracting background values from total contents.
Abstract: In order to distinguish whether heavy metal contents originate from a rock matrix or pollution, six different extraction techniques for copper, lead and cadmium were studied in Nagara River sediments in Gifu Prefecture, Japan. The extraction agents were hydrochloric-nitric acid mixture (1+1), 3N hydrochloric acid solution, 0.5N hydrochloric acid solution, 6M formic acid solution, 1N hydroxylamine hydrochloride plus 25% acetic acid solution and 0.05N ethylenediaminetetraacetic acid solution.The comparison of the six extraction techniques was conducted on the basis of the heavy metal contents originating from pollution, which was estimated by subtracting background values from total contents. For copper, 3N hydrochloric acid is preferable, but in sediments with poor ignition loss, 0.5N hydrochloric acid and 6M formic acid are recommended. 1N hydroxylamine hydrochloride plus 25% acetic acid is suitable for lead and cadmium.
TL;DR: In this article, natural waters in the Kinasa landslide area (Nagano Prefecture) were analyzed and the analytical results indicate that rocks are weathered chemically by H2CO3 and H2SO4 underground and silicate minerals are changing to clay minerals.
Abstract: Natural waters in the Kinasa landslide area (Nagano Prefecture) were analyzed. The analytical results indicate that rocks are weathered chemically by H2CO3 and H2SO4 underground and silicate minerals are changing to clay minerals. The concentration of HCO3- plus SO42- (meq·l-1) possibly indicates the extent of the chemical weathering and clay formation.
TL;DR: A bacterium of the Chromatiaceae family was isolated from a dense layer of phototrophic bacteria at the mid-depth of Lake Kaiike and changed to a sulfur-containing and finally to a motile sulfur-free rod-shaped bacterium measuring 1-2 μm in length to achieve the stationary phase of the culture.
Abstract: A bacterium of the Chromatiaceae family was isolated from a dense layer of phototrophic bacteria at the mid-depth of Lake Kaiike. The bacterium could be purely cultured in the medium given by PFENNIG and LIPPERT (1966). When sulfide was amply present in the medium, a very elongated form of the bacterium, which contained sulfur globules inside the cell, predominated. With decreasing sulfide concentration, it changed to a sulfur-containing and finally to a motile sulfur-free rod-shaped bacterium measuring 1-2 μm in length to achieve the stationary phase of the culture. Some environmental factors, pH, light, temperature, NaCl, vitamin B12 and sulfur compounds, on the bacterial growth were examined.
TL;DR: In this article, the spectral sensitivity of sensors in Lake Biwa was used to measure the spectral irradiance in terms of lux, quanta (400-700 nm) and total energy in the shortwave range (300-2500 nm).
Abstract: Underwater irradiances were measured in Lake Biwa in terms of lux, quanta (400-700 nm) and total energy in the shortwave range (300-2500 nm). The attenuation of irradiance was most rapid in energy, least in illuminance and in-between in quanta. Similar results were obtained from computations using the spectral sensitivity of sensors in conjunction with the earlier reported measurements of underwater spectral irradiance obtained for Lake Biwa. Thus, the differential attenuation of irradiance among these three expressions is due to the differences in the spectral sensitivity among the sensors together with characteristics of Lake Biwa regarding the selective absorption of spectral irradiance. Computed results also indicated that the penetration of energy flux in the range of 400-700 nm was virtually equal to that of photon flux. Analysis and discussion are extended to other lakes and marine environments reported in the literature. The significant deviations of underwater irradiance in lux from irradiance as photon flux density underscores the importance of using quanta or energy measurements in the photosynthetically active wavelength range in studies of primary production in aquatic habitats.
Journal Article•
TL;DR: Diel vertical movement of Neomysis intermedia population in Lake Kasumigaura, a shallow hyper-eutrophic lake, was investigated and it was found that this movement may be initiated by a critical light intensity encountered at certain times of sunset and sunrise.
Abstract: Diel vertical movement of Neomysis intermedia population in Lake Kasumigaura, a shallow hyper-eutrophic lake, was investigated. N. intermedia tended to concentrate more near the lake bottom during the daytime and to disperse throughout the whole water column at night. This behavior was observed at all growth stages, and the timing of this movement closely corresponded with sunset and sunrise. Diel vertical movement of N. intermedia may be initiated by a critical light intensity encountered at certain times of sunset and sunrise.
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TL;DR: The species composition and abundance of zooplankton of Lake Baikal were examined by vertical net collections in both pelagic and littoral areas in September 1980, suggesting the important role of minute suspended matter like bacteria as a food resource.
Abstract: The species composition and abundance of zooplankton of Lake Baikal were examined by vertical net collections in both pelagic (1, 300 m deep) and littoral (100 m deep) areas in September 1980. Thirteen species (two Copepoda, two Cladocera, eight Rotifera and one Protozoa) were identified, in which Episclaura baicalensis, Keratella quadrata and Vorticella sp. were dominant. Cladocerans were very scarce. Most of the zooplankters were distributed in the epilimnion (0-50 m deep), in which their biomass in the pelagic area was estimated to be 31.7 g (d.w.)·m-2. Some 83% of the biomass was occupied by E. baicalensis alone. Other copepods (including nauplii), rotifers and protozoans accounted for 13.9, 2.4 and 0.60 of the biomass, respectively. A large number of rotifers (7.4×106 animals·m-2) and Vorticella sp. (9.1×106) were also noted, despite the oligotrophic condition, suggesting the important role of minute suspended matter like bacteria as a food resource.
TL;DR: A method to collect unialgal Microcystis was devised considering the buoyancy of blue-green algae, which resulted in the collection of 1088.2μg·bottle-1 in one day, which was approximately 10 times higher than that in lake water.
Abstract: A method to collect unialgal Microcystis was devised considering the buoyancy of blue-green algae. A set of cylindrical bottles (53.3mmφ×250mm high) with a nylon net cover (3×3mm) placed upside down in a wire cage was suspended in lake water for several days. The amount of Microcystis as chlorophyll a collected by this method in August 1982 in Lake Kasumigaura was 1088.2μg·bottle-1 in one day, which was approximately 10 times higher than that in lake water.
TL;DR: The concentration of nine types of phosphate was observed at sixteen sampling sites from upstream to downstream in the Han River on the Korean Peninsula throughout the four seasons in 1978-1979 as discussed by the authors.
Abstract: The concentration of nine types of phosphate was observed at sixteen sampling sites from upstream to downstream in the Han River on the Korean Peninsula throughout the four seasons in 1978-1979. The concentration of all types of phosphate increased from upstream to downstream, especially in the Seoul City area, in terms of the landscape or population density of the basin. The ratio of particulate organic phosphate to total phosphate was constant from upstream to downstream irrespective of the total phosphate concentration level, suggesting that the plankton biomass increased in proportion to the total phosphate concentration. The ratio of dissolved ortho and hydrolyzable phosphate to dissolved total phosphate increased from several percent in the upstream area to more than 90 percent in the downstream region. Results of phosphate analysis in thirteen tributaries showed that the increasing concentrations of phosphate, particularly ortho and hydrolyzable phosphate from the upstream to downstream, were caused by drainage water from cultivated land in the middle reaches and mainly by domestic and industrial waste water in the downstream areas, which were heavily contaminated by fertilizer or synthetic detergent.