巻号一覧
44 巻 (1983)
- 4 号 p. 263-
- 3 号 p. 155-
- 2 号 p. 81-
- 1 号 p. 1-
44 巻, 4 号
選択された号の論文の11件中1～11を表示しています
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鉱害防止工事後の対馬・佐須川の底生動物相石崎 修造1983 年 44 巻 4 号 p. 263-268
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリーThe benthic community of the River Sasu was investigated in July 1981 to evaluate the influence of the construction to prevent mine-effluent. The communities in the lower reaches, where the effect of the mine-effluent was recognized in the previous surveys (MACHIDA and ISHlZAKI, 1975; ISHIZAKI and MACHIDA, 1980), showed a slight increase in the number of species and change of the dominant species. The heavy metal contents in the water of these areas had decreased in comparison with those of the previous surveys. Change in composition of the benthic community seems to be related to purification of the water quality by construction to prevent mine-effluent. There are some differences in distribution of species such as Gammarus nipponensis, Nemoura asakawae, and Semisulcospira bensoni along the water current, between the River Sasu and Se as a control river. This suggests that there is a decreased but still evident discharge from the abandoned mine in the River Sasu or that there are some discrepancies between the geographical features of both rivers.抄録全体を表示PDF形式でダウンロード (622K) -
伊藤 富子1983 年 44 巻 4 号 p. 269-276
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリー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 Hokkaidô. And the annual life cycles of G. bipertitus and G. japonicus are as in G. nukabiraensis.抄録全体を表示PDF形式でダウンロード (875K) -
戸田 任重, 高橋 正征, 市村 俊英1983 年 44 巻 4 号 p. 277-282
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリー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.抄録全体を表示PDF形式でダウンロード (660K) -
八木 明彦, 下平 勇, 寺井 久慈, 西條 八束1983 年 44 巻 4 号 p. 283-292
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリー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.抄録全体を表示PDF形式でダウンロード (1051K) -
Uroglena americanaの水平分布パターン吉田 陽一, 河口 克己, 門田 元1983 年 44 巻 4 号 p. 293-297
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリーIn order to clarify the patterns of horizontal distribution of Uroglena americana, investigations were conducted in the water area where the plankton accumulated in the northern basin of Lake Biwa in 1979. Small wings and a tail plane were set on an in situ fluorometer (Variosence II) with a thermistor and the instrument was towed by a ship with the speed of 4 knots at the depth 1 or 1.5 m.
The following remarkable variations of patterns were found in the horizontal distribution of chlorophyll a and water temperature :
1) Chlorophyll a concentration changes in reverse proportion to water temperature. 2) Chlorophyll a concentration changes parallel with water temperature. 3) Chlorophyll a concentration changes independently with water temperature.
As the cause why these various patterns were found, it was suggested that the types of vertical distributions of both U. americana and water temperature, the buoyancy of the plankton, the convergence and sinking of surface water, the convergence and upwelling of subsurface water, and so on, affected greatly the accumulation of the plankton and the formation of horizontal distribution patterns.抄録全体を表示PDF形式でダウンロード (629K) -
田中 靖志, 中西 弘, 津田 泰三, 松下 邦子1983 年 44 巻 4 号 p. 298-303
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリーThe Lake Biwa Eutrophication Prevention Ordinance, which prohibits the sale and use of domestic synthetic detergents containing phosphorus, was enforced in Shiga Prefecture in July, 1980. Before and after the enforcement of the ordinance, variations of the amount of Linear Alkylbenzenesulfonate (LAS) in rivers flowing into Lake Biwa have been investigated with the following results.
The amount of C12-LAS remained constant or slightly decreased after the enforcement of the ordinance. For example, at Hyota River, the amount of C12-LAS remained constant but the T-P amount decreased. This means that the inhabitants of the drainage changed their detergents from ones containing phosphorus to phosphorus-free ones. A correlation coefficient of 0.941 exists between C12-LAS and ignition loss of the river sediment. Thus, the remaining LAS seems to have some relation to the organic matter. The relative abundances of C13-LAS and C14-LAS in the total LAS (i. e. C10C14-LAS) in the river sediment were higher than those in the river water.抄録全体を表示PDF形式でダウンロード (708K) -
生嶋 功, Kozo HINO, José Galizia TUNDISI1983 年 44 巻 4 号 p. 304-310
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリーDaily oxygen budgets within a stand of submerged plants were measured in August, with the use of five cylindrical plastic tubes with different enclosure systems. The standing crop of living and dead plants at the experimental site was 47.9 and 37.5 g dry matter·m-2, respectively. Both daily total oxygen addition and that of oxygen loss in the water at the stand were estimated as 3.24 g O2·m-2·day-1. Daily gross productions of oxygen through photosynthesis by the submerged plants with their epiphytic algae and by epipelic algae accounted for 36% and 37% of the total oxygen addition, respectively. As much as 47% of the total loss was due to air released from water through diffusion, and 36% of that was due to total respiration. Both the daily amount of diffusion and its direction mainly depended upon the dissolved oxygen concentration at the researched water : daily amount of diffusion from water to air was estimated as 1.51g O2·m-2·day-1, and the highest rate of oxygen diffusion was 0.21g O2·m-2·hr-1 for 12-15 hours, when the rate of net oxygen production of 0.32 g O2·m-2·hr-1 was sustained.抄録全体を表示PDF形式でダウンロード (747K) -
Observation of Rain Infiltration by Lysimeter佐倉 保夫1983 年 44 巻 4 号 p. 311-320
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリー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.抄録全体を表示PDF形式でダウンロード (1154K) -
浜田 篤信, 前田 和加代, 岩崎 順, 熊丸 敦郎1983 年 44 巻 4 号 p. 321-328
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリー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.抄録全体を表示PDF形式でダウンロード (992K) -
Applied to Asano-gawa and Sai-gawa Rivers in Ishikawa Prefecture.墨田 廸彰, 渡辺 仁治1983 年 44 巻 4 号 p. 329-340
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリー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.抄録全体を表示PDF形式でダウンロード (1209K) -
寺井 久慈, 西條 八束1983 年 44 巻 4 号 p. 341-344
発行日: 1983/10/30
公開日: 2009/11/13
ジャーナル フリーPDF形式でダウンロード (939K)
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