摘要:

The ability of several multicellular marine algae to remove NaHC14O3from seawater in darkness has been compared. Members of the Phaeophyta removed approximately four to eight times more isotope than did members of the Rhodophyta and Chlorophyta examined. After 2 minutes of dark fixation, aspartic and glutamic acids were the main compounds identified in bothFucus vesiculosusandPolysiphonia lanosa. Radioactivity appeared largely in citric plus isocitric acids inFucus, whereas radioactive organic acids were not detected inPolysiphoniaeven after 30 minutes. Fractionation ofF. vesiculosusafter 2 hours of dark fixation showed that 95% of the total radioactivity recovered occurred in the fraction soluble in 70% acetone.Twenty-four hours of darkness immediately prior to a 2-hour dark fixation period reduced the total radioactivity incorporated to almost one-half of the control values. Either artificial seawater (one-fifth natural salinity) or a medium in which NaCl was substituted by KCl had little effect on the total radioactivity fixed during darkness. The distribution of isotope, however, showed some alterations.

ISSN:0008-4026    

DOI:10.1139/b63-029

出版商:NRC Research Press    

年代:1963

数据来源: NRC

摘要:

Tripterospora tetrasporaRai, Mukerji and Tewari spec, nov., a new member of the rare family Tripterosporaceae, has been described from Indian soils (pH 5.7–10.5). This species is characterized by the presence of four-spored asci.

ISSN:0008-4026    

DOI:10.1139/b63-030

出版商:NRC Research Press    

年代:1963

数据来源: NRC

摘要:

A new species ofAcremoniellaSaccardo, isolated from soil (pH 6.8) collected from Pallia, District Kheri, India, is named asA. serpentinaRai and Tewari spec. nov. because of the occurrence of strongly serpentine conidiophores.

ISSN:0008-4026    

DOI:10.1139/b63-031

出版商:NRC Research Press    

年代:1963

数据来源: NRC

摘要:

Spores ofTilletia contraversaKühn,T. laevisKühn, andT. caries(DC.) Tul. were found to contain ergothioneine, choline, betaine, and probably hercynine, as well as two unidentified trimethylammonium compounds. These substances, with the exception of betaine, were also detected in haploid mycelium ofT. contraversaand in its culture filtrate. One or more of these compounds could act as precursors for the trimethylamine released by bunt spores.

ISSN:0008-4026    

DOI:10.1139/b63-032

出版商:NRC Research Press    

年代:1963

数据来源: NRC

摘要:

Three new species ofBotryotiniaonCaltha palustrisL.,Ranunculus septentrionalisPoir., andFicaria vernaHuds. (Ranunculaceae) are described asB. calthaeHennebert and Elliott,B. ranunculiHennebert and Groves, andB. ficariarumHennebert. Each of the three species has aBotrytisstate of theB. cinereacomplex, and they thus constitute additions to the species already segregated from that complex, i.e.Botryotinia fuckeliana, B. convoluta, B. draytoni, andB. pelargonii. TheBotrytisstate ofB. ficariarumcan be distinguished morphologically.WhileB. ranunculiis a North American species andB. ficariaruman European one,B. calthaeis reported from both continents.

ISSN:0008-4026    

DOI:10.1139/b63-033

出版商:NRC Research Press    

年代:1963

数据来源: NRC

摘要:

The numbers of submerged and floating macrophyte species present in 29 ponds and lakes are inversely related to dissolved sulphates, concentrations of which rise sharply within about 4 to 5 miles of the smelters. Although pollution often leads to strong acidification, numbers of species are low even where sulphuric acid is almost wholly neutralized, and waters are above pH 6. Because sulphate ions are unlikely to be toxic at the levels encountered, and since pollution also increases the concentration of heavy metals in the waters, it is suggested that these may reach toxic levels near the smelters.Leptodictyum ripariumandEleocharis acicularisv.submersaseem to be most tolerant of smelter pollution, whileUtricularia vulgarisandPotamogeton epihydrusv.nuttalliiappear rather sensitive to it.

ISSN:0008-4026    

DOI:10.1139/b63-034

出版商:NRC Research Press    

年代:1963

数据来源: NRC

摘要:

A phytosociological analysis of the deciduous forest region of extreme southern Ontario is presented. One hundred and thirty-one stands were sampled quantitatively to determine the composition of the tree and sapling strata. A series of environmental characteristics were also measured or were carefully observed where measurement was impractical. The composition of the tree layer was expressed in terms of a series of importance values determined from measures of frequency, density, and dominance or basal area, on a relative basis, with the importance values for all trees in a stand summing to 300. An analysis of the relationship of the quantitative characteristics between all stands indicated the futility of the distinct association or distinct community approach to an understanding of forest ecological relationships in the region. An ordination of stands in relation to site moisture characteristics gave expression to the ecological tolerance of individual tree species and emphasized the continuous characteristics of forest patterns in the vegetational complex of the area.The forests of southern Ontario were related quantitatively to those of southern Wisconsin utilizing an index of regional influence based on overall importance for all tree species, in an attempt to interpret regional patterns within the Deciduous Forest Formation of North America.

ISSN:0008-4026    

DOI:10.1139/b63-035

出版商:NRC Research Press    

年代:1963

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b63-036

出版商:NRC Research Press    

年代:1963

数据来源: NRC