ISSN:0020-9309    

DOI:10.1002/iroh.19760610611

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThe fauna boring intoMontastrea annularisincludes sponges, bivalves, sipunculid and polychaete worms and barnacles. Sponges are most important in hard tissue destruction and account for more than 90% of the total boring in most heads. Bivalves and barnacles are locally important. Sipunculids and sabellids account for less than 4% of the total boring.The volume removed from coral samples by boring ranged from 3–60% and samples from a deeper bank reef were more highly bored than fringing reef samples. An average of 20% of the volume of bank reef corals, and 5% of the volume of fringing reef corals, was removed by boring.The distribution of individual borers is not a function of depth. The density and variety of borers and the extent of boring in coral heads is greater in older heads. The ratio of living coral surface to dead encrusted areas on colonies also influences borer density and the extent of borin

ISSN:0020-9309    

DOI:10.1002/iroh.19760610602

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThe Fosa de Cariaco off the coast of Venezuela is an anoxic basin which is subject to small seasonal fluctuations in the depth of the anoxic water. Samples taken in the interface region (between oxic and anoxic waters) contained from 13 to 37 species represented by 117 to 380 individuals. Species‐diversity, based onH′(s), was greater than that previously reported for samples from oxygen minimum regions. It is suggested that the relatively stable low dissolvedoxygen concentrations allow the development of diverse assembla

ISSN:0020-9309    

DOI:10.1002/iroh.19760610603

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThis, the first of two papers on the ecology of temporary streams, describes, in detail, the faunas of two such habitats in southeastern Canada. The adaptive mechanisms for coping with the summer drought are documented for a variety of species and faunal succession is shown to occur from the stream stage (fall‐winter) through the pool stage (spring) to the terrestrial (summer

ISSN:0020-9309    

DOI:10.1002/iroh.19760610604

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThe influence of nitrates (NH4NO3KNO3and Ca(NO3)2) on Diatom populations has been studied. These populations were isolated by enclosures with transparent walls, without bottom or lid, placed in an oligotrophic pond. The addition of NH4NO3generally resulted in a decrease in the number of Diatoms and the disappearance of some species. The addition of KNO3and Ca(NO3)2was followed, during some periods, by a very important increase ofAchnanthes minutissima, Fragilaria construensandGomphonema parvulum.

ISSN:0020-9309    

DOI:10.1002/iroh.19760610605

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractAn aliquot of a water sample taken from an artificial pond on the campus of the Faculty of Science, Tokyo Metropolitan University, was filtered with Whatman GF/C glass fiber filters. Urea was added to the filtered and unfiltered waters, respectively to a final concentration of around 10 μg‐at‐N/l. These samples were kept in 10 liter glass bottles, which were kept on the surface of the pond with rope. Changes in the concentrations of urea, ammonium, nitrate, nitrite, and the number of bacteria were traced from 15 June through 13 July, 1973.The urea added to the unfiltered water decreased to about 1 μg‐at‐N/l within first three days. The decrement of the urea seemed to proceed as a first‐order reaction with rate constant of 0.73 day−1. On the other hand, the urea added in the filtered water kept nearly the initial concentration for 18 days. As the number of bacteria in the filtered and unfiltered water were not significantly different, decrease of the urea in the unfiltered water may be ascribable to the participate fraction removed by the filtration. The urea was not decomposed by

ISSN:0020-9309    

DOI:10.1002/iroh.19760610606

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThe number, size and reproductive potential of the planktic Crustacea were compared from March to December 1973 in two Newfoundland lakes, namely Hogans Pond and Bauline Long Pond. In the first period of the study the total number of microcrustaceans was greater in the more fertile Hogans Pond, but after October all species in Hogans Pond declined catastrophically. The relative numbers of individual species are detailed, some being more abundant in one lake and some in the other. Body lengths of most copepods were the same or greater in Hogans Pond than in Bauline Long Pond, but the cladoceranDaphnia catawbawas larger in Bauline Long Pond. The number of eggs carried per female was usually the same or greater in Hogans Pond, except forDiaptomus minutusandDaphnia catawbain the spring.

ISSN:0020-9309    

DOI:10.1002/iroh.19760610607

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThe annual fluctuations in the occurrence of 91 taxa which were identified, made the recognition of 4 main seasonal populations possible. Trends were observed, as well as analogies to other patterns of distribution. On an average, more than half of the fauna was displaced from month to month, but the variation in the density of subtropical neuston appeared to be less over an annual period than it was during the day, and from region to region. The dominance of certain species and occurrence of neuston throughout the year demonstrated, that regionally at least a biocoenosis exists continously at the surface of the sea.

ISSN:0020-9309    

DOI:10.1002/iroh.19760610608

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractA technique for analyzing the stability of a phytoplankton‐nutrient interaction model is described which may be applicable to a broader range of models. It is shown that periodicity of solutions in a differential equation does not imply the same for the corresponding difference equation mode

ISSN:0020-9309    

DOI:10.1002/iroh.19760610609

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY

摘要:

AbstractThe egg cases, eggs, and different stages of life cycles ofTropisternus lateralis(Fabricius), T. blatchleyi D'Orchymont, and T. collaris (Fabricius) are described. A table is given for separating the various developmental stages of the three species.

ISSN:0020-9309    

DOI:10.1002/iroh.19760610610

出版商:Akademie Verlag, Berlin    

年代:1976

数据来源: WILEY