巻号一覧
49 巻 (1988)
- 4 号 p. 227-
- 3 号 p. 149-
- 2 号 p. 71-
- 1 号 p. 1-
49 巻, 2 号
選択された号の論文の8件中1～8を表示しています
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中西 正己, 渡辺 信, 寺島 彰, 左子 芳彦, 近田 俊文, Keshab SHRESTHA, Hemanta R. BHANDARY, ...1988 年 49 巻 2 号 p. 71-86
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーSome limnological variables were investigated and analyzed in Phewa, Begnas and Rupa Lakes of Nepal in the late-monsoon and dry seasons. From the data on the levels of TN, TP, Chl. a and phytoplankton primary productivity, Phewa Lake seemed to be meso-eutrophic, and Begnas and Rupa Lakes to be eutrophic. The gradient of the regression line of PC on Chl. a ranged from 42.1 to 71.4 and suggested that phytoplankton in the investigated lakes had a moderately high or high relative growth rate. In comparing the C : N : P : ratios of the seston with REUFIELD Ratio and other data on phytoplankton chemical ratio, all the lakes appeared to be P-limited. Variation of species diversity of phytoplankton was great between both the seasons in each lake and tended to depend mainly on the share of the predominant species. Microcystis aeruginosa, in total cell number in Phewa and Begnas Lakes, and on that of Tabellaria fenestrata in Rupa Lake. The similarity index of phytoplankton indicated that phytoplankton in Phewa Lake were similar to those in Begnas Lake but not to those in Rupa Lake.抄録全体を表示PDF形式でダウンロード (2152K) -
寺井 久慈1988 年 49 巻 2 号 p. 87-92
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーDenitrifying activity in Lake Fukami-ike emerged early in April 1986 as well as in 1985. In contrast to 1985, owing to the depletion of nitrate, denitrifying activity in 1986 did not develop after early May, when its mean and maximum value were 0.033 and 0.155μg-at N·1-1d-1, respectively.
On the other hand, the denitrifying bacterial population in the lake grew slowly from April (3 cells ml-1) to June (19 cells ml-1). The maximum population level was only one fourth of that in 1985. The difference in the development of the denitrification process between 1985 and 1986 was discussed mainly in terms of the supply of nitrate through precipitation and runoff. From analysis of the correlation between precipitation at Anan Observatory and NO3- concentration in Lake Fukami-ike, it is concluded that precipitation during late February to early March determined the nitrate level in the vernal circulation period of the lake, and it is suggested that the nitrate level affected the extent of initial development of the denitrification in the lake. Moreover, NO3- in the lake was almost completely depleted during the long drought from 20 May to 15 June 1986, and in situ denitrifying activity was also almost completely suppressed. Under these circumstances, the dependence of denitrifying activity on the precipitation was shown by a correlation between maximum denitrifying activity and the amount of the precipitation during the preceding 20 days.抄録全体を表示PDF形式でダウンロード (778K) -
田畑 真佐子, 橘 和佳, 鈴木 静夫1988 年 49 巻 2 号 p. 93-98
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーThe pH dependence of phosphatase activity in lake water was investigated in eight Japanese lakes. Lakes Akanuma, Rurinuma and Bisyamonnuma were classified as acidotrophic and contained much SO42-, Cl-. Lakes Shibuike, Nagaike, Ichinuma were classified as dystrophic and contained much TOC, while Lakes Shinseiko and Ashinoko were both regarded as harmonic lakes. The phosphatase activities of Lakes Akanuma (pH 3.9), Rurinuma (pH 4.5), Shibuike (pH 4.5) and Nagaike (pH 5.6) were high under acidic conditions (pH 5-6), but low under alkaline conditions (>pH 8). The enzyme activity of Lake Bisyamonnuma (pH 5.7) was high under alkaline condition, while that of Lakes Ichinuma (pH 6.2), Shinseiko (pH 7.3) and Ashinoko (pH 7.3) was high under both acidic and alkaline conditions. Thus the phosphatase activity of these lakes was closely related to pH rather than components (SO42-, Cl-, TOC etc) dissolved in the water.
The phosphatase collected in the water and that in homogenates of plankton from Lakes Shibuike and Shinseiko were fractionated by gel chromatography. Several phosphatases with various molecular weights (50, 000-270, 000) were observed under acidic condition in a plankton homogenate from Lake Shibuike. The molecular weight of the main dissolved phosphatase was 180, 000. In a water sample from Lake Shinseiko the molecular weight of the main soluble phosphatase with activity under alkaline conditions was 180, 000. This value corresponded to the molecular weight of the main phosphatase in the homogenate of plankton collected from the lake.抄録全体を表示PDF形式でダウンロード (731K) -
(I)珪藻汚濁指数(DAIpo)値墨田 廸彰1988 年 49 巻 2 号 p. 99-108
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーIn this study DAIpo (Diatom Assemblage Index to organic water pollution) values of 418 samples were obtained at 183 stations in 52 rivers in the Hokuriku District. The average DAIpo values and the histogram of the distribution of DAIpo values were obtained in several river basins. From there data the state of the organic water pollution of the investigated rivers was examined. In the histograms of the distribution of DAIpo, the modes were of higher grades, suggesting that there are many clean water areas in river basins of that area.
Some 25 taxa were chosen as dominant species in the present study. The ecological classification of these taxa according to their tolerance to the degrees of organic water pollution corresponded fairly well with the classification by WATANABE, et al. (1986). A pollution spectrum was made for the above mentioned 25 taxa which showed the change of dominant species according to the degrees of organic water pollution based on DAIpo was made. Its purpose is to determine the suitability of the values of DAIpo as biological informations. As a result, DAIpo values were found to be a proper indicator of water quality in comparatively clean rivers of the Hokuriku District.抄録全体を表示PDF形式でダウンロード (951K) -
大高 明史, 氏家 淳雄, 馬渡 峻輔1988 年 49 巻 2 号 p. 109-117
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーComposition and abundance of zoobenthos in the profundal zone of Lake Oze-numa (36° 56′N, 139°18′E) were studied at two sites, Lake Center and Off Nushiri, from May to September 1986. Among the eight taxa recorded, three species (Tubifex sp., Limnodrilus hoffineisteri, and Chironomus sp.) accounted for more than 95.5% of the macrobenthos in number. Species diversity, density, and biomass of macrobenthos were lower at Lake Center (8.8m deep in average) than those of Off Nushiri (6.8m). Oxygen content was probably an important factor in these differences between the sites. At Off Nushiri, Tubifex sp. and L. hoffineisteri reproduced throughout the study period but with low proportions ; pupae of Chironomus sp. were found only in late June.抄録全体を表示PDF形式でダウンロード (1299K) -
吉岡 崇仁, 和田 英太郎, 西條 八束1988 年 49 巻 2 号 p. 119-128
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーCarbon and nitrogen isotope ratios in sedimentary organics and δ15N of NO-3 and dissolved organic nitrogen are reported for two subalpine lakes in order to establish an isotopical and biogeochemical framework characterizing lake ecosystems.
A two-source model is applicable to evaluate the contribution of land derived organics to the sedimentary organic matters of Lake Kizaki. A kind of chromatographic sedimentation of the land-derived particles with different specific gravity was suggested from the river mouth to the mid-lake. The size distributions of the isotope ratios support this inference. Denitrification and the associated oxidation reduction reaction seemed to enhance the 15N content of sedimentary organics during epidiagenesis of the sedimentary organic matters. The isotopic compositions of the sedimentary organics and the soluble nitrogenous compounds can be useful indicators to characterize a biogeochemical structure of a lake system. Significant increase in δ13C of sedimentary organics by 3% and in δ15N of NO-3 and DON by 2 to 7% were found under eutrophication caused by human impact, in the highly eutrophic lake, Lake Suwa. External loading of nutrient salts by human activities and its associated heavy water bloom of Microcystis are responsible for these phenomena.抄録全体を表示PDF形式でダウンロード (1379K) -
加藤 憲二, 呉 壽完, 沖野 外輝夫1988 年 49 巻 2 号 p. 129-134
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーBacterial attachment to the solid surface in the littoral zone of a eutrophic lake was studied by a simple method using a glass slide under epifluorescence microscopy with acridine orange staining. The initial rate of bacterial attachment was around 1 x 105 cell cm-2 hr-1, and the attached bacterial number amounted to about 106 cells cm-2 in 24 hr during experiments in June in Lake Suwa. The contribution of attached bacteria with large cell size and that of dividing cells to the total attached bacteria showed a tendency to increase with immersion time.抄録全体を表示PDF形式でダウンロード (793K) -
松山 通郎1988 年 49 巻 2 号 p. 135-141
発行日: 1988/04/30
公開日: 2009/11/13
ジャーナル フリーSamples of the bacterial plate found at the dissolved O2 H2S interface of Lake Kaiike were incubated at different levels of light and H2S supply. Two species of sluggishly moving bacteria, a large-celled phototrophic bacterium and a bean-shaped one resembling Macromonas bipunctata, were dominant in the bacterial plate. Without supply of H2S these bacteria were displaced by a small coccoid immotile green alga even at a light intensity as low as 400 lux. The rate of H2S produced by the bacterial plate samples, about 0.6 mg S.1-1.day-1, was insufficient to maintain the dense bacterial populations. Two bacteria were considered to be much affected by H2S supply from the underlying layer, although they have different H2S concentrations for their optimal growth.抄録全体を表示PDF形式でダウンロード (1320K)
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