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Volume 45, Issue 2
Displaying 1-10 of 10 articles from this issue
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Yuzuru KUSAKA, Haruo TSUJI, Yuzo TAMARI, Kimio NISHIMURA, Yoshinao FUJ ...1984 Volume 45 Issue 2 Pages 93-99
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSChemical species of the shallow groundwaters collected from the Arima rhyolite strata around Sanda and Nishiwaki cities are studied. Since the chemical composition of the igneous effusive rock is reasonably representative of rocks of the continental crust, the water quality is important from the geochemical and environmental viewpoints. The concentrations of 28 chemical species, pH and ER are determined by conventional chemical and neutron activation analyses. By showing log-normal distribution character of the concentrations, the median value schematically obtained in the frequency distribution curve is proposed as most suitable as the chemical composition of groundwaters in the strata. It is also pointed out that the CO2 weathering process is the most dominant phenomenon controlling the water qualities.View full abstractDownload PDF (886K) -
Tadao KAKINUMA, Kunimitsu INOUCHI, Yuuji DOHGANE1984 Volume 45 Issue 2 Pages 100-110
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSA new method for solving the problem of the unsteady motion of the interface between fresh and salt waters in confined aquifers is presented, using the following three approximations : 1) The viscosity of salt water is equal to that of fresh water; 2) the compressibility of the granular skeleton of the medium and the compressibility of the fluid in the salt water region are equal to those in a fresh water region; 3) in the equation for the thickness of the salt water layer, the term containing the storage coefficient is ignored. The numerical solutions by the new method are compared with the ones obtained by solving directly basic equations. For the special case of non-pumping and one-dimension, an analytical solution is found. It is in good agreement with the numerical solution by SÁ DA COSTA and WILSON (1979), and LIU et al. (1981), and it is similar to the experimental result by BEAR and DAGAN (1964).View full abstractDownload PDF (1637K) -
Hisayuki TERAOKA1984 Volume 45 Issue 2 Pages 111-115
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSConcentrations of suspended solids and discharges were measured in the period from 1975 to 1980 in the Takahashi River system (111km long, 2670km2 drainage basin). The sampling site was 10.4 km up the estuary, where the riverbed averages 0.73m above sea level.
When the flux of suspended solid (g·sec-1) and the discharge (m3·sec-1) were plotted on Y axis and X axis, respectively, the relation Log Y=2.02 Log X-0.83 (n=75, r=0.94) was found. By substituting the regression line for the daily average discharge, the flux of suspended solid (g·day-1) was estimated. When the discharge increased very greatly as a result of heavy rainfall between June 29 and July 1, 1979, its amount (g·hr-1) was estimated by substituting the above regression for the hourly average discharge. Thus, the amount of suspended solids transported during 1979 from river to estuary was estimated at 75×106kg·yr-1 (discharge : 1976×106m3·yr-1), while the amount for the day of June 29 reached 28×106kg·day-1 (or 37% of the total).
A comparison between the average daily concentrations of elements and their concentrations on the June 29th heavy discharge day was undertaken to fully appreciate the effects of heavy rains.View full abstractDownload PDF (794K) -
Yosunori WATANABE1984 Volume 45 Issue 2 Pages 116-125
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSDecomposition and transformation processes of cellular and extracellular products of lake phytoplankton photosynthesis were determined using a 14C tracer technique under laboratory conditions. The cellular organic matter was consumed by phytoplankton respiration in the early stage of incubation and decreased to 19% of the initial amount for 30 days at 25°C. A shift occurred in the chemical constitution of the predominant cellular organic matter : hot ethanol soluble and hot water soluble components changed into hat water insoluble ones. After decomposition for 85 days, 14.7% and 1.5% of the cellular products were transformed to particulate and dissolved organic matter, respectively. The extracellular products, which were 9.3% of the total photosynthetic products, were easily metabolized and decomposed by lake bacteria. After 133 days, 19.4% and 7.5% of the initial extracellular products changed to particulate and dissolved organic matter, respectively. During the course of the decomposition, a marked difference was observed in gel filtration profile of the dissolved organic matter derived from the extracellular products.View full abstractDownload PDF (1593K) -
Toshi NAGATA1984 Volume 45 Issue 2 Pages 126-133
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSAnnual fluctuations of bacterial numbers were surveyed at four stations in Lake Biwa between 1981-1982. The total count obtained by acridine orange direct microscopic count method changed in the order of 105-106cells per ml at St. Ie (sited in the pelagic area of the north basin), and 106-107cells per ml at three stations in the south basin. The percentage of the viable count to the total count (V/T ratio) ranged from 0.009 to 1.81%, and the ratio tended to be higher in more eutrophic water. Generally, at St. Ie, the vertical profiles of both total and viable counts clearly correlated with those of chlorophyll-a, pH and dissolved O2 (% saturation); however, hypolimnetic O2 depletion had no effect on bacterial numbers. Rank correlation analysis for the samples of epilimnion also showed significant correlations (p<.0005) between bacterial numbers and pH, chlorophyll-a and dissolved O2 (% saturation), but not pheopigments. These results suggest close relationships between phytoplankton and bacteria in Lake Biwa.View full abstractDownload PDF (1222K) -
Michiaki SUMITA, Toshiharu WATANABE1984 Volume 45 Issue 2 Pages 134-141
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSWATANABE (1982) developed an equation to obtain the river pollution index (RPIB) in an attempt to estimate the general state of river pollution. This equation has been obtained from the water quality chart acquired through the traditional method of water quality estimation by indicator organisms.
The value of RPIB obtained from such a water quality chart was somewhat ambiguous for estimation of the degree of pollution, because the traditional water quality chart indicates the distribution of an area with only four to six different degrees of water pollution. The present authors consider that the degree of water pollution in the river actually changes gradually and continuously and that they can not thus be divided numerically into definite classes by degrees.
From the above-mentioned point of view, SUMITA and WATANABE (1983) proposed a new approach to the general estimation of river pollution using a new diatom community index (NDCI). In this study the river pollution indices (RPID) were computed in seven rivers in the Noto Peninsula of Ishikawa Prefecture using the new method proposed by SUMITA and WATANABE (1983).
From the values obtained, it became clear that the water quality of the rivers was worse than expected and that the degree of water pollution approximated those of rivers polluted by waste water.View full abstractDownload PDF (1091K) -
Tadao KAKINUMA, Kunimitsu INOUCHI, Yuuji DOHGANE1984 Volume 45 Issue 2 Pages 144-152
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe authors presented a new method, which will appear in this Journal, to solve the problem of the unsteady motion of the interface between fresh water and salt water in confined aquifers.
In this study, the Galerkin-finite element method is used to simulate the two-dimensional movement of the interface in a confined aquifer in the estuary of the Naka River, Tokushima Prefecture. The distributions of the chloride concentration predicted with the numerical model were in satisfactory agreement with the results of field observation.View full abstractDownload PDF (1378K) -
Takayuki HANAZATO, Masayuki YASUNO, Toshio IWAKUMA, Noriko TAKAMURA1984 Volume 45 Issue 2 Pages 153-157
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe seasonal, mutual succession between Bosmina longirostris and Bosmina fatalis occurred at Takahamairi Bay in Lake Kasumigaura. The same succession was observed in the enclosures set up in the bay. To reduce the amount of reactive phosphorus, the enclosures were treated with aluminum sulfate. The predominant period of B. fatalis in summer became shorter in the treated enclosures than in the untreated ones or open water. The appearance of B. fatalis seemed to accord with the time when netplankton larger than 20 μm increase; it varied in the treated and untreated enclosures. Since the netplankton was mostly Microcystis aeruginosa, the increase of this alga likely caused succession of the two species of Bosmina.View full abstractDownload PDF (719K) -
Michiro MATSUYAMA1984 Volume 45 Issue 2 Pages 158-164
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSA Phototrophic bacterium was isolated from the bacterial plate of Lake Kaiike (surface, 0.15 km2; max. depth, 11.6 m) by use of the medium of KÄMPF and PFENNIG (1980). The bacterium was coccoid or diplococcoid, 1-3 μm in length, and contained bacteriochlorophyll a. When much H2S was present, the bacterium united to large sedimentary aggregates, and all cells contained sulfur globules. With decreasing H2S concentration, the cells became motile and changed into a purple suspension. At depletion of H2S, the bacterium consumed sulfur globules, and it entered the stationary growth phase. The bacterium was similar to Thiocystis violacea. Effects of some environmental factors such as pH, light intensity, temperature, NaCl concentration and sulfur compounds on the bacterial growth were examined.View full abstractDownload PDF (2420K) -
Shigeru SHOJI, Toshikatsu IRIYE, Yasuhiro SATOH1984 Volume 45 Issue 2 Pages 165-168
Published: April 30, 1984
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSA UM-2 ultrafilter of Diaflo Membrane (Amicon Co.; nominal molecular weight cut off, 1, 000) entrapped amino acids and monosaccharides with molecular weights less than the nominal cut off level. The degree of entrapment of amino acids changed with the change in pH of the solution : neutral amino acids slightly increased (66.4→74.0%) and basic AA increased (6.0→56.0%), whereas acidic AA decreased (86.7→32.3%) with increasing pH from 4 to 10, and that of glucose remained practically unchanged with pH.
The present results suggest that, even when the molecular weights of organic molecules in natural waters are sufficiently below the nominal cut off level of the UM series filters, they will be selectively entrapped by the UM series filters, if they have ionic sites or highly polar molecules. The degree of entrapment may change with the change in pH of the water.View full abstractDownload PDF (545K)
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