摘要:

AbstractIn each of the species examined — 4 Chlorophyceae, 7 Phaeophyceae and 4 Rhodophyceae — the optimum temperature for photosynthesis was apparently higher in summer material than in winter material. In the brown algae the optimum temperature for the apparent photosynthesis lies between 20°C and 23°C, in the green algae and in most of the red algae between 25° and 30°C. In most of the red algae the activity decreased markedly at 35°GC, while a considerable part of the green algae survived at this temperature. In 50% of the species of brown algae examined the photosynthetic activity decreased at 30°C and was completely lost at 35°C, while in the remaining species a strong resistance to high temperatures wa

ISSN:0020-9309    

DOI:10.1002/iroh.19730580402

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

摘要:

AbstractSeveral aspects of sea water enrichments were previously studied and the method for growth‐potential measurements was improved. The experiments presently reported were carried out in order to estimate the validity of the method. Natural sea water was used from two different marine areas. Eleven enrichments are added to the samples; their concentrations are those of the ASP 2 solution of PROVASOLI et al. (1957); one, two or three of the components are missing.Chaetoceros lauderi, Phaeodactylum tricornutumandSkeletonema costatumare used as test organisms.The data clearly indicate that the information obtained from sea water enrichments can be different from those given by the usual analysis of chemical nutrients. For the same chemical substances missing, there is a striking discrepancy between the results obtained from different test strains. On the contrary, within the array of sea water samples, the same enrichments are always growth‐promoting or growth‐inhibiting for each of the three orga

ISSN:0020-9309    

DOI:10.1002/iroh.19730580403

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

摘要:

AbstractA list of the subterranean fauna of the river basin and cave waters of the southern Harz Mountains and Kyffhäuser Mountains is given.Both the chemistry of the subterranean waters and the food chain relationships of the subterranean fauna are considered. The biota of the caves is compared to other subterranean fresh water biotopes, and the geographic distribution of the observed species is noted

ISSN:0020-9309    

DOI:10.1002/iroh.19730580404

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

摘要:

AbstractThis study aims at providing quantitative information on the distribution of sediment‐inhabiting Testacea in high‐mountain lakes. The seasonal and spatial changes in species distribution. abundance and biomass are described. Through discussion of the relevant findings of other authors. the importance of some of those factors responsible for the Testacean distribution in time and depth is indica

ISSN:0020-9309    

DOI:10.1002/iroh.19730580405

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

摘要:

AbstractUnder controlled laboratory conditionsDaphnia roseaSARS is strongly repelled by substances secreted byElodea, Nitella, andMyriophyllum.This phenomenon can be easily demonstrated in a large glass U‐tube having a small sprig of hydrophyte at the surface of the water on one side of the U‐tube. It can also be demonstrated in a long narrow aquarium having an incomplete vertical plastic divider at the center, and with the hydrophyte on one side of the divider. Simulated plastic aquarium vegetation in control aquaria has only a slight repellent or „shading”︁ effect. The implications of this phenomenon in the hydrophyte zone of lakes and ponds are

ISSN:0020-9309    

DOI:10.1002/iroh.19730580406

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

摘要:

AbstractThe present paper belongs to a series dealing with Gnathostomulids from the West Atlantic coasts (RIEDL 1970a, b; 1971a, b; STERRER 1970, 1971, 1972). Others will include additional species descriptions, distribution patterns and improved sampling techniques. Organization will generally follow the format of previous Gnathostomulida papers. The following description based on studies of living individuals is the fourth species in the genusAustrognathariaSTERRER, 1971 and the second to be described from North America. Primary emphasis is placed on characters of systematic importance; supplementary data including a distribution pattern are mentioned briefly under “Notes and Obersvations.”I am deeply indebted to Dr. WOLFGANG STERRER (Bermuda Biological Station for valuable material and generous assistance. I would also like to thank Dr. REINHARD RIEGER (Chapel Hill) for his helpful suggestions, the University of North Carolina at Chapel Hill for facilities, and Dr. STEVEN WAINWRIGHT (Duke University) for his financial subsidy. Further support: NSF grant No. XA 120 (R. J. RIEDL, principal investigator) and North Carolina Board of Science and Technology grants No. RA 012 and RA 023, University Research Council VF

ISSN:0020-9309    

DOI:10.1002/iroh.19730580407

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

摘要:

AbstractThe green algaChaetophora incrassata, which LUTHER describes as alkaliphile, occurs in Lake Kraaz in the northern part of the G. R. D., although it is situated in a sandy region. The appearane can be explained by the special ecological conditions, especially the high input of nutrients and the pH value of 7.4.

ISSN:0020-9309    

DOI:10.1002/iroh.19730580408

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19730580409

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19730580411

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19730580414

出版商:Akademie Verlag, Berlin    

年代:1973

数据来源: WILEY