Saprolegnia on roach (Leuciscus rutilus) and carp (Cyprinus carpio) [Translation from: Acta zool.pathol.Antverpiensia 43 107-123, 1976]

There is, in nature, as well as in the aquarium, a parasitic disease known as 'mousse' and which attacks predominantly fish. It is caused by Phycomycete fungi, genus Saprolegnia. The fungus causes external lesions and covers the fish with a thick white layer from whence comes the name 'mousse', commonly attributed to the disease, for which the scientific name is Saprolegnia. This article provides an overview of Saprolegnia infections on fish in nature and aquaria and then discusses symptomology of Saprolegnia in the mirror caro and t roach in more detail.

Respiration and the efficiency of energy during embryonic development of Asellus aquaticus L. (Crustacea) [Translation from: Vestsi Akademii Navuk Belorusskoi SSR, Seriya Biyal. 1978(5) 112-114, 1978]

Experimental studies were carried out on the transformation of matter and energy during embryonic development of the isopod Crustacea Asellus aquaticus L. under two constant temperatures. Material for the experiments was collected in the quarry lakes of the Kurasovshchin-zone (city-Minsk) at 9°C in April and at 18°C in June, 1977. The rate of consumption of oxygen per specimen by eggs and embryos of Asellus aquaticus was observed and dynamics of the basic biological characteristics during embryonic development studied.

Comparative drift studies on streams in lower Austria (Flysch, gneiss and chalk formations) [Translation from: Schweizerische Zeitschrift fur Hydrobiologie 30 138-185, 1968.]

Seasonal changes and flooding have an extraordinarily great influence on the drift of organisms. The free water space plays the main part in the provision of food for some fish (Salmo trutta - trout): drift and content of the stomach are balanced here (Simuliidae): whereas others (Thymallus vulgaris) only selectively chose certain animals living at the bottom (molluscs). The total drift, drift of organisms and drift of organic material and minerals, plays a main role in the rate of production in streams. Besides the biology of the organisms living on the river bed, also the geological and hydrographical situation of the area plays a very important role for the composition of the drift. During the years 1964-1966 three streams in the characteristical geological formations flysch, gneiss and chalk of lower Austria were studied in regard to their drift. The Tulln (above St. Christopen), the Krems (above Senftenberg) and the Schwarza (above Hirschwang) seemed to be ideal for this comparative study because they are easy to reach. After summarising the hydrography and chemistry of examined rivers, the author examines the relationship between water level and total drift and the stratification of the total drift before analysing the drift of living organisms. Also considered are seasonal changes of drift of organisms and drift of exuviae.

Taxonomic description of Peridinium lomnickii, P.lomnickii var. splendida and P. wierzejskii [Translation from: Flora Slodkowodna Polski. Tom 4. Cryptophyceae, Dinophyceae, Raphidoiphyceae, p326,328-330. Warsaw, 1974]

This partial translation from a larger paper provides taxonomic descriptions of the dinoflagellates Peridinium lomnickii, P.lomnickii var. splendida and P. wierzejskii. Illustrations are included.

Dangeardia sporapiculata n.sp., the term 'apiculus' and the species limitation of some chytrids [Translation from: Sydowia 16 324-330, 1963]

Taxonomic observations are given on Dangeardia sporapiculata n. sp. Furthermore the term 'apiculus' and the species limitation of some chytrids are being discussed. It is concluded that the newly described species Dangeardia sporapiculata does not fit satisfactorily into the present system of phlyctidiacee, because their characteristics do not agree exactly with any genus.

On the classification of lakes and lake-like bodies of the Ukraine [Translation from: Gidrobiologicheskie Zhurnal, Kiev 19(2) 100-101, 1983]

In the Ukraine there are several thousand large, medium and small lakes and lake-like reservoirs, distinguished by origin, salinity, regional position, productivity and by construction a significant number of large and small water bodies, ponds and industrial reservoirs of variable designation. The problem of national systems necessitates the creation of specific schemes and classifications. Classifying into specific types of reservoir by means of suitable specifications is required for planning national measures with the objective of the rational utilisation of natural resources. It is now necessary to consider the present-day characteristics of Ukranian lakes. In the case of the Ukraine it is possible to use two approaches - genetical and ecological. This paper uses the genetical system to classify the lake-like water bodies of the Ukraine.

Individual growth and seasonal cycle of Daphnia middendorffiana in an Alpine lake [Translation from: Memorie dell'Istituto Italiano di Idrobiologia Dott.Marco de Marchi 26 41-83, 1970]

The problem of the peculiar reproductive biology of the cladoceran Daphnia middendorffiana is investigated from a cytological viewpoint, and by direct observation the meiotic phenomena of the eggs both subitaneous and resting is studied. and during maturation, the true mechanism of the succession of reproductive phases of different ecological significance. Samples were collected in the Italian Alpine Lake of Campo 4°.

A study of the reproductive biology of dace in the middle Ob [introduction , summary and table captions only] [Translation from: Trudy tomsk. gos. Univ. 125, pp.77-91]

The Siberian Dace (Leuciscus leuciscus baicalensis (Dyb)is an important trade fish in Siberian waters. In the Ob basin more than 30,000 centners are produced annually. Catches of dace fluctuate significantly both between different rivers and between years in the Tomsk region. Defining the stocks of dace in the waters of the Tomsk region and explaining the fluctuations over time seems to be a very important and relevant question for the workers of the fishing industry. An answer, however, requires an accurate knowledge of the biology of dace; its reproductive, feeding and migration habits and the conditions of wintering etc. In the following we examine one of the above questions i.e. the biology of the reproduction of dace. The study was carried out in the Middle Ob in May 1951. This tranlations provides the introduction, summary and table captions only of the original article.

Mellum Island (southern North Sea): dynamic processes and sedimentary structures. I. Southern tidal flat, transition zone and high-surface.[p.72 (Blasensand) only][Translation from: Senckenbergiana Maritima 11, 59-113, 1979]

This partial translation of a longer article describes the phenomenon of ”Blasensand”. Blasensand is formed when sedimentation of dried out sand is suddenly flooded from above. A more detailed explanation of Blasensand is given in this translated part of the paper.

The role of infusoria and bacteria as food for Cyclopoida in Rybinsk Reservoir [Translation from: Trudy Instituta Biologii Vnutrennykh Vodnany 22(25), 37-42, 1971]

Despite the fact that it is a long time sinc e the methods of collection and quantitative estimatio n of protozoa were worked out data on the abundance of these animals in freshwaters are not very numerous. Nevertheless, Infusoria and Rhizopoda at high densities are widespread in the water and sediments of lakes and reservoirs. In order to find ou t the importance of infusoria as a food source for cyclopoids we carried out experimental investigations using C14. For this three species of cyclopoids, widely distributed in open regions of Rybinsk reservoir were selected: Cyclops vicinus, Mesocyclops oithonoides and Kesocyclops leuckarti. The data presented give evidence that the species investigated are able as predators to consume infusorian plankton arid bacteria in the form of flocs or small clumps of detritus.

Concerning the current conditions and transport of sand in the shallow water areas off the coast of the south-eastern North Sea [Translation from: Hamburger Kustenforschung 29 [pages 41-43 only], 1974]

With the aid of the German Research Association in the central programme 'Sand movements in the German coastal region', an investigation into the current conditions in the shallow water areas of the coasts of the south-eastern North Sea between Sylt and the Weser estuary was carried out by the author. Foundations of the work are 19 continuous current recordings in five profiles normal to the coast from years 1971 to 1973. Off the coasts of the south-eastern North Sea varying tidal currents impinge; they are currents whose directions may vary periodically through all points of the compass. They are caused by the circulating tides in the North Sea (Amphidromien). The turning flow movement experiences a deformation in the very shallow coastal waters, and as it happens the flow turning movement in the case of high tide continues right up onto the outer flats, while here and in the fore-lying shallow water areas around the time of low water (on account of the small depths of waters), there prevails a more variable current. A result of this hydrodynamical procedure is the development of counter currents. This partial translation of the original paper provides the summary of this study of of the mudflat areas between the Elbe and Weser.

Towards a knowledge of chytrids. Part 3. Spirospora paradoxa nov.gen. - nov.spec. [Translation from: Archiv fur Protistenkunde 54 510-528 [pages 522-525 and plate 28 only], 1926]

This partial translation of the original paper provides morphological observations on the fungus Spirospora paradoxa. Illustrations are included here.

Colpodella pugnax Cienk., Protomonas amyli Cienk., Protomonas spirogyrae Borzi and Protomonas huxleyi Haeckel [Translation from: Die Pilzthiere oder Schleimpilze (ed. W. Zopf), pp. 115-124. Breslau, Eduard Trewendt, 1885]

Morphological observations are given for Colpodella pugnax Cienk., Protomonas amyli Cienk., Protomonas spirogyrae Borzi and Protomonas huxleyi Haeckel.

Descriptions of Oscillatoria agardhii, O.prolifera and O.rubescens only [Translation from: Translation from: Flora Slodkowodna Polski. Tom 2. Cyanophyta, Glaucophyta (ed. K. Starmach) p350-352. Warsaw, Polska Academia Nauk, 1966]

Short morphological observations are given for the Cyanophyceae Oscillatoria Agardhii, Oscillatoria prolifica and Oscillatoria rubescens.

Studies on the submerged plant community in Lake Biwa. I. Distribution and productivity of Egeria densa. A submerged plant invader in the south basin [Translation from: Physiol.Ecol.Japan 17, 283-290, 1976]

Egeria densa (PLANCH.) ST. JOHN, a submerged plant invader, forms a wide submerged plant zone, particularly along the west coast of the south basin, Lake Biwa. The macrophyte occupies over 82% of the plant zone in the basin and its biomass reaches 93% of the total. The estimated annual net production was approximately 1 kg dry wt./m2 in a dense area, which is about 4.5 times as much as the net production by phytoplankton in an offshore area of the basin. Although the area covered by the macrophyte is only 5.8% of the total of the basin, it produced about one-tenth of the total annual primary production. In the most productive season Egeria produced 46% of the total primary productivity. Thus, the macrophyte never be neglected when one considers the energy flow or material circulation in the basin. This study was initiated in order to clarify the role of submerged macrophytes, particularly E. densa, in Lake Biwa. The following points are reported in this paper: the distribution of macrophytes in the south basin; seasonal change in standing crop of E. densa; seasonal change in values related to production, utilizing a model proposed by Ikushima with its parameters experimentally determined.