巻号一覧
40 巻 (1979)
- 4 号 p. 169-
- 3 号 p. 115-
- 2 号 p. 61-
- 1 号 p. 1-
40 巻, 1 号
選択された号の論文の5件中1～5を表示しています
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吉田 冨男, 相崎 守弘, 浅見 輝男, 槙島 直樹1979 年 40 巻 1 号 p. 1-9
発行日: 1979/01/30
公開日: 2009/10/21
ジャーナル フリーThe biological nitrogen fixation and denitrification were studied in Lake Kasumiga-ura to evaluate the significance of the biological processes for nitrogen enrichment and the self-purification in aquatic environments. The water and sediment samples were collected from several sites and analyzed for the amount of inorganic nitrogen, the nitrogen-fixing activity by acetylene reduction method, the denitrifying activity by nitrous oxide formation and the numbers of total heterotrophic bacteria and denitrifying bacteria. No significant activities of nitrogen fixation and denitrification were found in the lake water in this study. The rate of denitrification in sediments was about two orders of magnitude higher than that of nitrogen fixation. The average microbial activities of nitrogen fixation in sediments sampled in July, August and December were 0.02, 0.11, and 0.14 μg N/g/day, respectively ; those of denitrification are 4.1, 8.1, 93.4 μg N/g/day, respectively. These results suggest that the surface sediments in Lake Kasumiga-ura have a high potential for self-purification of nitrogenous compounds in water and sediments.抄録全体を表示PDF形式でダウンロード (1647K) -
相崎 守弘1979 年 40 巻 1 号 p. 10-19
発行日: 1979/01/30
公開日: 2009/10/21
ジャーナル フリーThe growth rates of microorganisms were determined for a periphyton community grown on artificial substrata submerged in the midstream of the Tamagawa River. The growth rates were measured seasonally for bacteria, algae, the heterotrophic periphyton community and the whole periphyton community. The doubling times were as follows : bacteria, 3-10 hours; sessile algae, 12-28 hours; heterotrophic periphyton community, 15-104 hours; and periphyton community, 12-59 hours. The growth rates showed a good correlation with water temperature, and the Q10 values were as follows : bacteria, 1.9; sessile algae, 1.6; heterotrophic periphyton community, 2.5; and periphyton community, 2.2.抄録全体を表示PDF形式でダウンロード (1266K) -
松山 通郎1979 年 40 巻 1 号 p. 20-28
発行日: 1979/01/30
公開日: 2009/10/21
ジャーナル フリーThe growth of Chromatium sp. in Lake Kaiike, a small coastal lake on the Kamikoshiki Island, was considered from the viewpoint of growth responses of Chromatium sp. in culture to different gradients of environmental factors such as temperature, light, pH and H2S. In July, 1978, Chromatium sp. densely populated the upper part of the H2S layer and the density and assimilation rate of the bacterium attained to 2×106 cells/ml and 700 mg C m-3 day-1, respectively. Incident light and H2S concentration at the habitat, being less than 1% of that just beneath the surface and less than 3 mg S/l, lay within the ranges where the growth of laboratory-cultured Chromatium sp. increased in proportion to their quantities. But the fact that the habitat of Chromatium sp. is confined to a depth below the algal compensation depth indicates that light condition does not exert such a pronounced effect on the in situ growth of Chromatium sp. On the contrary, the supply of H2S to the habitat supposedly would have an important effect on the growth of this bacterium.抄録全体を表示PDF形式でダウンロード (1286K) -
小林 重喜, 山内 和子1979 年 40 巻 1 号 p. 29-39
発行日: 1979/01/30
公開日: 2009/10/21
ジャーナル フリーThe pollution of river by laundry wastewater and the main sources of orthophosphate ion in Nagara river water were studied.
Rivers in the Nôbi plain were undoubtedly polluted by laundry wastewater, and their MBAS concentration increased from the upper to the lower reaches.
The greater part of soluble phosphorus compounds in Nagara river water was orthophosphate. The soluble orthophosphate P concentration in the river was not markedly affected by the phosphorus from laundry wastewater.
On the other hand, the correlation coefficient of concentration between soluble orthophosphate P and urea N was 0.385 and the correlation of P with N was significant on 5 % of significant level. In the period of rice plant cultivation, one of the main sources of orthophosphate ion and urea in the Nagara river water was outflow from plowland on which manure and organophosphorus agricultural chemicals has been spread, in the river's drainage area; another was the effluent from raw sewage treatment plants in the river basin. But in winter and spring, it seemed that the two constituents in the river were chiefly supplied by domestic miscellaneous wastewater and the effluent mentioned above.抄録全体を表示PDF形式でダウンロード (1600K) -
由佐 悠紀1979 年 40 巻 1 号 p. 40-48
発行日: 1979/01/30
公開日: 2009/10/21
ジャーナル フリーThe deep phreatic groundwater level in the Beppu alluvial fan area presents a typical annual variation under the influence of the seasonal variation in rainfall, though the effect of each rainfall on it is not clear. The level also fluctuates due to the barometric pressure change, being different from shallow phreatic groundwater levels. These phenomena are analyzed in the present study by the theories of pressure propagation and infiltration through the thick unsaturated layer. The infiltration process of the rainfall is approximately described by the linear diffusion equation, which gives a reasonable relation between the rainfall at the ground surface and the recharge at the water table. In the course of the analysis, a method for the evaluation of some hydrological properties of the water-bearing layer is presented.抄録全体を表示PDF形式でダウンロード (1282K)
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