ISSN:0020-9309    

DOI:10.1002/iroh.3510610424

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractAn increase in the phosphate concentration due to severe pollution is without real toxic effect for the phytoplankton in eutrophic lakes, although the various species have a variable tolerance against high concentrations. Experiments on photosynthesis and growth were made with cultures of two algae,Chlorella pyrenoidosaandNitzcshia palea, using phosphate concentrations much higher than ever found in nature. The tolerance decreases with rising pH. This seems not to be due to a higher ratio of secondary phosphate at a high pH. Nor is the rise in the osmotic pressure apparently the cause of the decrease in the growth rate at high phosphate concentrations.

ISSN:0020-9309    

DOI:10.1002/iroh.3510610402

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractMany years' research into the concentration of unstable organic matter in ocean waters from many regions of the World Ocean is compiled. The relative amounts of this matter, as determined by counts of heterotrophic bacteria, are presented as three‐dimensional illustrations, depicting specific ocean areas from the surface to the sea floor. The merits of using this information in oceanography are discussed, particularly in cases where other parameters are indistinct. In many cases, this is viewed as the best method for determining the origin of water layers at various depths, and of following the movement of water masses in the ocea

ISSN:0020-9309    

DOI:10.1002/iroh.3510610403

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractVariations of species composition and population size of planktonic algae were studied in relation to the different nutrient levels in a eutrophic pond and an oligotrophic lake. The results obtained were discussed in comparison with the changes in photosynthesis and chlorophyll of several algal populations cultured under different nutrient conditions. As based on unialgal culture experiments two types of algae (theChlorella‐type and theMelosira‐type) could be distinguished with regard to variations of photosynthesis and chlorophyll in response to different nutrient levels. Distribution of theChlorella‐type algae may be confined to eutrophic waters, while theMelosira‐type algae can be distributed widely in waters from oligotrophic to eu

ISSN:0020-9309    

DOI:10.1002/iroh.3510610404

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractLittle research has been made on the litoral algal flora of unpolluted high mountain lakes and streams. Since the algal flora is often used to estimate the water quality, it is of great value to know more about the ecology of benthic forms living under extreme oligotrophic conditions.An investigation was made of the benthic and littoral microphytic vegetation of Esteragne torrent, and Lac de Port‐Bielh in the High Pyrenees. Both waters combine a low calcium content with a consistently basic pH. A comparison of their flora with that of other lakes may help to deal with the problem of whether the algal flora is determined more by the calcium content or the pH.The algal flora of Esteragne torrent differs little from that of low‐calcium streams of the central European highlands. In Lac de Porth‐Bielh there is a distinct depth‐zonation among the dominant algae. The dominant taxa at a depth of 0–0,5 metres are:Schizothrix lacustrisf. lutescens, Sch. calcicola, Gloeocapsa tornensis,Pleurocapsa minorwithCyanostylon microcystoidesandHydrococcus cesatiiparticularly on the undersides of the stones; from 0,5 to 1,5 m: a massive growth ofNostoc zetterstedtii; from 2,5 to 4,5 m:Schizothrix funalis;from 7 m:Nitella flexilis.In addition the lake includes a number of rare and little known forms such as?Onkonemasp., of.Desmosiphon maculans, Lyngbya lachneri, Homeothrix sinensis, Chantransia chalybeav.profunda, Siphononema polonicumstatuschamaesiphonoides.Green algae were almost completely absent from the upper zones, in contrast to the usual findings. The littoral flora has a very distinctive character, and is not directly comparable with that usually found in lakes with either high or low calcium content. A certain resemblance to lakes with a high calcium content can be found only if all the forms present particularly with lower abundances are considered. The very strong development of lithophytes should be emphasized in contrast to their usually low density in lakes with low calcium content.The systematic section deals with systematic and taxonomic problems in a number of diffic

ISSN:0020-9309    

DOI:10.1002/iroh.3510610405

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractIn the turbulent, turbid water body of a river, lake, reservoir or ocean, the light intensity for a phytoplankton individuum is time‐dependent. But current production equations are based on time‐independent light conditions. A mathematical model for the photosynthetic oxygen production under the simple condition of intermittent light is developed. It consists of one nonlinear algebraic and one linear differential equation of the first order. For the photosynthetic apparatus a global effective relaxation time τ is given. The model is proved with the data published by Warburg (1919). It shows, coupled with an empirical relation for τ, a good qualitative and quantitative agreement with experimental re

ISSN:0020-9309    

DOI:10.1002/iroh.3510610406

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractStepwise multiple regression analysis has been used to evaluate the relative importance of environmental variables for primary productivity in oceanic areas off Washington and Oregon, USA. Special emphasis has been placed on the area affected by the Columbia River plume. In the plume, a large proportion of the total variability in primary productivity data is explained by only four variables: chlorophylla, nitrate, depth of the photic zone, and temperature. In ambient sea water, the significant variables are salinity, temperature, solar radiation of the previous day, vertical stability in the upper 100 m, and phosphate. Analysis of the combined data indicates that, in the spring, primary productivity depends on chlorophyllaconcentration alone. The results are explained from the biological and physical points of view. The usefulness of multiple regression analysis for marine ecosystem studies appears to be limited.

ISSN:0020-9309    

DOI:10.1002/iroh.3510610407

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThis species was previously reported only from its type locality (Zanzibar). In 1975 a specimen was collected near Madras at a depth of 15–25 m. A description of the species along with a drawing is provide

ISSN:0020-9309    

DOI:10.1002/iroh.3510610408

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.3510610410

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.3510610413

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY