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Volume 39, Issue 3
Displaying 1-7 of 7 articles from this issue
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Michiro MATSUYAMA1978 Volume 39 Issue 3 Pages 97-102
Published: July 30, 1978
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSVertical distributions of chlorinity, water temperature, dissolved oxygen and hydrogen sulfide have been obtained from Lake Kaiike, a small coastal lake on Kamikoshiki Island, Kagoshima Prefecture, during April, 1976 and October, 1977. Lake Kaiike (surface area : 0.15 km2; maximum depth : 11.6 m) is stratified between brackish water layer above (chlorinity, 6.6-12.2 ‰) and saline layer below (chlorinity, more than 17 ‰). During the spring and autumn, high temperature of up to 39°C were found in the boundary. In the lower water layer an anoxic condition prevailed throughout the year and a noticeable amount of hydrogen sulfide was contained. From autumn to winter the lake was exposed to wind-induced mixing process and the stratified condition was somewhat altered. With the gradual rise of sea level during spring to summer seawater intruded into the bottom by seepage through the gravel bar.View full abstractDownload PDF (701K) -
Michiro MATSUYAMA, Eiji SHIROUZU1978 Volume 39 Issue 3 Pages 103-111
Published: July 30, 1978
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSThe purpose of the present paper is to show the importance of photosynthetic sulfur bacteria, Chromatium sp., as an organic matter producer in Lake Kaiike, a small lake situated on the north coast of Kamikoshiki Island. The lake (surface area : 0.15 km2, maximum depth : 11.6 m) waters are brackish above and very saline below. The deeper part of the saline water contains a remarkable amount of hydrogen sulfide. Water at the O2-H2S boundary contains a dense population of Chromatium sp. The bacteria concentration attains a maximum of 5.3 106 cells/ml, forming the so-called “bacterial plate.” The carbon assimilation rate at the boundary reaches 30-80 % of the total one. A large number of zooplankton such as Brachionus sp. and Tintinnopsis sp. inhabit the water above the bacterial plate. Chromatium sp. appears to have an important role as a food source in supporting the high zooplankton biomass in Lake Kaiike.View full abstractDownload PDF (1141K) -
Dispersion of salts caused by oscillating interface between saltwater and freshwater in porous mediaHiroshi DEI1978 Volume 39 Issue 3 Pages 112-117
Published: July 30, 1978
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSFrom salt concentration distributions of the groundwater in coastal aquifers where the saltwater intrusion has occurred, it was found that tidal oscillations and the groundwater flow of that area influence the dispersion of salts. In this paper, the quantitative relationship between tidal oscillations and dispersion is analyzed by means of the statistical method, and examined by a series of experiments. It is found that the dispersion coefficient is in proportion to the amplitude and frequency of oscillation, and that the dispersion constant exists for each porous medium according to their physical properties.View full abstractDownload PDF (708K) -
Jun SHIMADA, Shigemi TAKAYAMA, Yuichi SUZUKI1978 Volume 39 Issue 3 Pages 118-122
Published: July 30, 1978
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSSagamihara Plain is located in the central part of Kanagawa Prefecture and has an area of 180 square kilometers (Fig. 1). The authors surveyed the groundwater of this region from Nov.17 to Nov.22, 1977. Groundwater level, pH, RpH, water temperature, and electric conductivity of groundwater were measured at 171 wells for residential use (Fig. 2). The ground level of observed wells was decided from the city plan map of 1 : 2500 scale. On the basis of these data, a contour map of groundwater tables in this region was drawn as Fig. 3.
Figure 3 shows that there are three different groundwater tables in the area according to geomorphological conditions. Many spring exist along the terrace cliff between the upper and middle terraces. Judging from the shape of the groundwater table and the relationships between groundwater table and rivers, it is concluded that the groundwater of this region is recharged mainly by the infiltration of precipitation through the plain surface.
The tritium concentration in groundwater and springs sampled at 13 points in Sagamihara Plain (Fig. 4) supports the hydrogeological classification of the groundwater in this region and clarifies the rate of mixing between the infiltrated precipitation with high concentration through Kanto loam and the water with low concentration existing in gravels under the loam.View full abstractDownload PDF (816K) -
Jiroh ITOH, Ryo TATSUKAWA1978 Volume 39 Issue 3 Pages 123-129
Published: July 30, 1978
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSFecal pollution of the riverwaters in the Matsuyama Plain (Fig.1 and 2) was investigated by using coprostanol (5β-cholestan-3β-ol) as an indicator. Coprostanol in the riverwaters was extracted by hexane and silylated by BSTFA. The silylated Coprostanol was determined by using a gas chromatograph-mass spectrometer equipped with a multi-ion detector (GC-MS-MID).
In the waters of the rivers which flow through residential districts without sewer system, the concentration of coprostanol increased from 0.8ng/l to 8100ng/l continuously downstream (Table 2-(1) and Fig.3). This fact suggests that fecal drain, which comes from the insufficiently functioning septic tanks, flows into the rivers.
In Ishite River, one of the main rivers in the Matsuyama Plain, the fecal sources were the outflows from Oku-Dogo hotspring town and hog farms, but not from the septic tank systems (Table 2-(2) and Fig.4).
In the Matsuyama Plain, fecal pollution of waters of the tributary streams was severer than that of the main rivers (Table 2-(3) and Fig.2). In particular, the concentration of coprostanol in the waters of Miyamae River, whose upper reaches has a municipal sewage treatment plant along the bank (Fig.1), was the highest in the Matsuyama Plain (24000ng/l).
The concentration level of coprostanol in the aquatic environment, which is not polluted severely with feces, is postulated to be below 500 ng/l.View full abstractDownload PDF (972K) -
Miyoko HIGO, Toshiharu WATANABE1978 Volume 39 Issue 3 Pages 130-136
Published: July 30, 1978
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSThe composition of the off-shore epilithic diatom communities was studied in the southern basin of Lake Biwa during the period from April to July 1976.
The species Achnanthes minutissima, Synedra sp., Cymbella turgidula, Cymbella ventricosa, Synedra rumpens var. familiaris, Cymbella tumida, Synedra delicatissima were generally prominent. The results of cluster analysis using the similarity index on epilithic diatom communities were shown in Fig. 2 and Fig. 3. Fig. 3 was mapped out by the prominent species above mentioned. The variation of the diatom communities at each station was arranged in Fig. 4, which might be closely related to flow of water masses e. g., inflow from the northern basin, polluted inflow from the eastern vicinity and domestic or industrial waste water from cities, villages and their vicinity.View full abstractDownload PDF (840K) -
Taishi ODA, Hajime UEKI1978 Volume 39 Issue 3 Pages 137-142
Published: July 30, 1978
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSBenthic fauna have frequently been used to assess the impact of domestic and industrial waste discharge on receiving water. The primary object of this study was to give an accurate assessment of the water quality on the basis of Benthic fauna in the Iseri River, Kumamoto City. The drainage basin of this river is occupied by farmland at its upper stream and an urban area at its lower one.
Water samples were collected monthly at six stations along the river, month by month from November of 1975 to October of 1977, and some chemical properties (DO%, MPN, COD, BOD, NH3-N, Cl-, Na+, Ca2+, SO42-, 4.3Bx, T-Re) were analysed. Benthic faunae were sampled quarterly from 1976 to 1977, with two samples collected at each station by a server net.
Chemical properties of water samples at the lower stream were clearly different from those at the upper one, reflecting the influence of the wastewater effluents. Also, species composition of benthic animals showed a similar trend.
A statistically significant correlation was observed between some chemical parameters and biological indices, such as species diversity and pollution index.View full abstractDownload PDF (732K)
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