摘要:

AbstractA survey is given of physical, chemical and biological events in the water‐mass of a productive lake (Esthwaite Water, N. England) during summer stratification. They are interrelated in terms of i) responses to meteorological changes (ii) susceptibility to density stratification (iii) participation in acid‐base and redox systems, with interactions of these (iv) modification due to the generation of particulate material from soluble precursors (v) limiting factors in such bio‐generation (vi) mechanisms of internal nutrient loading, and (vii) control by the characteristics of individual plankters. The significance is demonstrated of differential inputs of meteorological variables, and especially of biological production and degradation, for determining the overall structure and metabolism of the

ISSN:0020-9309    

DOI:10.1002/iroh.19860710402

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

摘要:

AbstractThe null hypothesis for this research was that oyster parasites and disease were not associated with increased thermal loading in the Chesapeake‐Delaware area. The American oysterCrassostrea virginica(GMELIN) was held at a reference station and a test station in the Chesapeake and Delaware Bay area for a year. Oysters from the four stations were sampled monthly for histological studies and parasite incidence together with the infestation of the polychaetous annelidPolydora websteri.The incidence of parasites and disease conditions from histology was negligible. Based on these results the null hypothesis was accepted, that oyster parasites and diseases did not increase with increased thermal loading. However, infestation of the oyster commensalP. websteriincreased with increased temperatur

ISSN:0020-9309    

DOI:10.1002/iroh.19860710403

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19860710404

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

摘要:

AbstractThe variability in physical, chemical and biological properties was examined for a number of glacier melt streams in south Victoria Land, Antarctica. Streams flowed for between one and two months. Stream water temperatures (range = 0–11°C) varied over short (hr) time scales whilst discharges varied considerably between streams (range 0.001–15 m3s−1) and over diel cycles. Solar radiation and air temperature were major determinants of stream discharge. Variability in discharge was reflected in variability in nutrient chemistry and sediment load. Nitrogen and phosphorus varied considerably between streams; the meltwaters early in summer contained 10–20 times higher levels of dissolved N and P than later in the season. Within stream nutrient levels were modified by dense algal growths and penguin rookeries. Epilithic algal communities were made up predominantly of cyanophyceae which formed mats and crusts. Longitudinal and horizontal variability of species in the communities in selected streams is described. Analyses of algal cover and biomass (chlorophylla) show that substrate type and flow rates are of greater importance than nutrients in influencing algal abundance and biomass. In some streams biomass values of over 20 μg Ch.acm−2were recorded, much of which remains viable but inactive over the antar

ISSN:0020-9309    

DOI:10.1002/iroh.19860710405

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

摘要:

AbstractThe investigation deals with ways of increasing the number of species by means of artificial introduction of algae. After inoculation, the authors recorded 212 species and forms: 128 in spring, 165 in summer, 119 in autumn and 61 in winter. The maximal cell number of phytoplankton occurs in summer, the minimal in winter. The active role of algae in the sewage purification is shown.

ISSN:0020-9309    

DOI:10.1002/iroh.19860710406

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19860710408

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

摘要:

AbstractData from simultaneous studies of three algal communities (phytoplankton, epipelon and epiphyton) in an edaphically eutrophic lake are compared. Comparisons include both physical and chemical parameters along with those involving the biota.

ISSN:0020-9309    

DOI:10.1002/iroh.19860710409

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19860710410

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19860710413

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY

ISSN:0020-9309    

DOI:10.1002/iroh.19860710414

出版商:Akademie Verlag, Berlin    

年代:1986

数据来源: WILEY