巻号一覧
45 巻 (1984)
- 4 号 p. 253-
- 3 号 p. 173-
- 2 号 p. 93-
- 1 号 p. 1-
45 巻, 3 号
選択された号の論文の9件中1～9を表示しています
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小川 吉夫, 市村 俊英1984 年 45 巻 3 号 p. 173-177
発行日: 1984/07/30
公開日: 2009/11/13
ジャーナル フリーPhytoplankton diversity in 23 water bodies of different trophic status was evaluated by the SHANNON index. High diversity was obtained in meso- and slightly eutrophic waters, whereas a low diversity was observed in oligo- or highly eutrophic waters.抄録全体を表示PDF形式でダウンロード (651K) -
高橋 剛一郎, 東 三郎1984 年 45 巻 3 号 p. 178-186
発行日: 1984/07/30
公開日: 2009/11/13
ジャーナル フリーIn order to crarify how channel alteration affects fish habitat, fish densities, stream morphology and flow conditions were researched at both altered and unaltered sections in a stream. In the unaltered section the stream bed was very undulating, and differentiation of riffles and pools was clear. Waterflow was affected by morphological factors and became turbulent. In the altered section, the bed shape was flat, differentiation of riffles and pools was not clear, and waterflow was laminary as compared with the former section. The dominant fish was Oncorhynchus masou in the unaltered secion, and Barbatula toni in the altered section. Why the former fish was not dominant in the altered section was discussed in relation to their feeding habit, the flow conditions, multiformity of environment. The low carrying capacity of O. masou in the altered section reflects the uniform environment which was producted by the channel alterations.抄録全体を表示PDF形式でダウンロード (1506K) -
雨宮 由美子, 中山 大樹1984 年 45 巻 3 号 p. 187-193
発行日: 1984/07/30
公開日: 2009/11/13
ジャーナル フリーMicrocystis causing water-bloom in eutrophic lakes during summer is present in the most part as colonies with gelatinous sheath. There are, however, few reports on the characteristics of the gelatinous sheath. We, therefore, examined its characteristics using Microcystis collected from Lake Suwa.
The sheath materials were prepared by continuous centrifugation, followed by filtration and lyophilizaton. The sheath materials were mainly composed of 35.4 to 47.0% of polysaccharides with uronic acids and 18.2 to 24.5% of protein. One gram contains the following amounts of each metal : 17.9 mgNa, 7.77 mgK, 23.3 mgCa, 3.73 mgMg, 8.48 mgFe, 0.751 mgMn, 0.338 mgZn, 0.065 mgNi and 0.031 mgCu. The contents of Na, Ca, Fe, Mn and Zn in the sheath materials were five or more times as much as those in whole cells of Microcystis. The concentration factors of Fe and Mn of the sheath materials were large, in the order of 104 to 105. The adsorption of metals by the only sheath materials was shown and fitted Freundlich isotherms which showed the following sequence of a ffinities : Fe Zn Mn Cu, Ni.抄録全体を表示PDF形式でダウンロード (4242K) -
渡辺 直1984 年 45 巻 3 号 p. 194-203
発行日: 1984/07/30
公開日: 2009/11/13
ジャーナル フリーA freshwater snail, genus Semisulcospira was studied in the three islands inside Lake Biwa, Japan. A large and pronouncedly nodulated form of S. niponica was found off Takeshima and Shiraishijima Islands as well as off Chikubujima Island from which this form was described. Among the three islands, the snails become larger and nodes on the whorls become more intense with the decreasing area of the islands.
A new species, S. morii, is described from Chikubujima and Takeshima Islands. This species coexists with S. niponica, and is abundant on a rather deeper bottom according to the monthly survey of vertical distribution. Three unknown types of Semisulcospira were also found off Takeshima and Shiraishijima Islands. All of the types live on the rocky bottom there, but in adult and embryonic shell characteristics they resemble the decipiens group which live on the sandy or muddy bottom of the coastal zone of Lake Biwa. From the above survey, several ecological and evolutionary problems are presented on Semisulcospira in these islands.抄録全体を表示PDF形式でダウンロード (6841K) -
吉村 孝一, 荒 勝俊, 林 克己, 川瀬 次朗, 辻 和郎1984 年 45 巻 3 号 p. 204-212
発行日: 1984/07/30
公開日: 2010/11/22
ジャーナル フリーRiver Die-Away tests of linear alkylbenzene sulfonates (LAS) and soap were carried out. At 10 mg El-1 of surfactant in river water, dissolved organic carbon (DOC) due to soap decreased slightly faster than that due to LAS, while no significant difference was observed in the change of particulate organic carbon (POC) of either surfactant. As the result of River Die-Away test of soap at 30 mg El-1, POC level increased in the course of biodegradation of soap (till about day 15 of test period). The increase of POC level was inferred to be due to bacterial floc partially containing unsoluble soap (fatty acid salts). Fatty acids in the course of biodegradation of soap were analyzed by a pre-labelling HPLC method. The extent of biodegradation of fatty acids decreased in the following order :
C12>C10≅C8>C14≅C18 : 2>C18 : 1>C16>C18
LAS was degraded according to Swisher's “Distance Principle” that the longer the alkyl carbon chain length, and the longer the distance between the far end of alkyl chain and the phenyl group, the faster the biodegradability becomes. Optimum temperature for LAS biodegradation was about 25°C. Although soap was degraded at both 10 and 40°C, LAS was not degraded at those temperatures. However, after incubation of river water containing LAS at 20°C, LAS was degraded even at 10°C.抄録全体を表示PDF形式でダウンロード (1233K) -
宮下 衛, 安野 正之1984 年 45 巻 3 号 p. 213-219
発行日: 1984/07/30
公開日: 2010/11/22
ジャーナル フリーThe growth and reproduction of Asellus hilgendorfii was studied at 5°C, 15°C and 25°C in the laboratory. The females began to produce their first brood at about 4 mm in length after five weeks at 25°C and after about ten weeks at 15°C. The animals reared at 5°C died before maturation. The mean number of broods per female was 2.6 and 4.3 times at 15°C and 25°C, respectively. The mean incubation period was 18.3 and 9.4 days, and the mean parturition interval was 29.9 and 15.4 days at respective temperatures. The mean brood size was 27.4 and 34.7 an 15°C and 25°C, respectively. A. hilgendorfii grew faster and bred more often in their lifetime, compared with other species of the genus Asellus.抄録全体を表示PDF形式でダウンロード (870K) -
中島 重旗, 小田 泰史, 松並 裕子1984 年 45 巻 3 号 p. 220-230
発行日: 1984/07/30
公開日: 2010/11/22
ジャーナル フリーThe interrelationship between some environmental factors and indicator species of bottom fauna phase in the river was investigated and measured in the Kuma River in Kumamoto Pref. during September and November of 1982 and 1983. Among environmental factors, suspended solids in river water are seriously affected by flash floods, and these suspended solids affect matters attached to riverbed gravels. Pollution index, biotic index and diversity index have been used to clarify the degree of water pollution in the river in addition to chemical water quality such as BOD, nitrogen and phosphates. The numbers of individual CHIRONOMIDAE larvae have a good positive correlation (r= 0.824—0.847) with the weight of attached matters.
Bottom fauna grew to the critical level of standing crop at 700 dry mg/100 cm2 of attached matters on the riverbed gravels. It was also very clear that numbers of species, numbers of individual and standing crops of bottom fauna have a close correlation with their living space, e. g., ratio of gravel to sampling area (occupation ratio), and flatness of gravels.
It was found that biotic indicators should be studied and reported more precisely regarding the riverbed environmental factors such as gravel size, living space, standing crop on the gravel.抄録全体を表示PDF形式でダウンロード (1598K) -
Maria S. R. IBANEZ, 中西 正己, 手塚 泰彦1984 年 45 巻 3 号 p. 231-239
発行日: 1984/07/30
公開日: 2009/11/13
ジャーナル フリーNear- and offshore waters of the south basin of Lake Biwa were bottled, enriched with nitrogen and phosphorus, alone and in combination, and incubated for a long period in the surface layer of the lake. Experiments were carried out during four seasons in the nearshore water and for one season in the offshore water. The phytoplankton response to wastewater was also investigated. Results of the experiments showed that nitrogen and phosphorus in combination have the most stimulatory effect on phytoplankton growth, whereas there was some evidence that nitrogen rather than phosphorus stimulated phytoplankton growth more in terms of chlorophyll a and total cell number. Nitrogen plus phosphorus and nitrogen treatments remarkably changed the phytoplankton composition leading to an increase in green algae. Polluted river water without nutrient addition also promoted algal growth.抄録全体を表示PDF形式でダウンロード (1266K) -
伊藤 富子1984 年 45 巻 3 号 p. 240-248
発行日: 1984/07/30
公開日: 2010/11/22
ジャーナル フリーDrift of lepidostomatid larvae (Goerodes complicatus, G. satoi and G. nukabiraensis) was studied in Creek Masunosawa, Sapporo, northern Japan, 1977-1978. Additionally, larval behavior in the drift was preliminarily observed in the laboratory and field.
In the creek, benthic and drifting larvae of G. nukabiraensis were few. Drift of two other species increased at night, and the nocturnal drift was more marked in summer. Drift of lepidostomatid larvae was little in June and winter, and significantly related to water temperature as well as to creek discharge. Higher drift was observed at times of rapid growth and increased activity.
In the water-circulated aquarium, larvae of G. complicates and G. satoi came up to water surface, where they floated with extended legs, grasping the substrata. The floating larvae always has a silken thread the other end of which was fixed onto the wall of the aquarium. The climbing larvae increased at night and due to lack of food, decreased after the fallen leaves of terrestrial plants were supplied. Also at the slow-flowing creek sites, larvae of the three species drifted with extended legs, in the upper stream, holding onto the silken thread secured to stones located upstream. By means of this silken thread, larvae probably keep themselves float for long periods and can drift even farther at slow-flowing sites.抄録全体を表示PDF形式でダウンロード (1367K)
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