Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    The distribution and production of Gammarus pseudolimnaeus (Crustacea: Amphipoda) along a reach of the Credit River, Ontario (1981)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 11 (1981), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SUMMARY. The population density of the univoltine amphipod Gammarus pseudolimnaeus was estimated monthly from April 1977 to June 1978 along a 600-m reach using a form of removal sampling at 0.5, 1.5 and 2.5 m from the bank. The probability of catching an amphipod with three sweeps over an area of 0.15 m2 was 0.95. Drift and upstream migration were measured for 24 h, also monthly. Population density varied from 1600 m−2 (newly-hatched young in July) to 26 m−2 (adults) within 3 m of the bank with 95% confidence limits of 40–60% of the mean; density was highest 〈 1 m from the bank and beyond 3 m it declined to insignificant levels. No significant difference could be shown between the total catches in the drift and upstream nets over a year and there appeared to be no net migration of amphipods. Mean drift was 2 amphipods day−1.Growth was estimated from the length composition of monthly samples. Annual production (P) was 29.4 kg ha−1 for one generation of the amphipod with a P/B ratio of 4.65. Egg production accounted for only 2% of this estimate. Recruitment was calculated from regressions relating female length to clutch size and egg development time to temperature in the laboratory; mean temperature was measured in the field.Mortality was greatest in July at the beginning of the generation. It was high again in September and during winter; at these later times it was suggested that starvation occurred in addition to predation. Annual consumption (C) of organic matter for the generation calculated from published data on feeding rate was 1547 kg ha−1 which results in a P/C ratio of 1.9%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1981.tb01251.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Field estimates of feeding rate for Gammarus pseudolimnaeus (Crustacea: Amphipoda) in the Credit River, Ontario (1981)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 11 (1981), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SUMMARY. The feeding rate of G. pseudolimnaeus was measured monthly for 7 months in the field by monitoring the decline in weight of gut contents when the amphipod was starved. This decline was modelled by an exponential regression of weight on time. As the amphipods appeared to be continuous feeders, feeding rate was calculated by multiplying the dry weight of a full gut by the specific rate of emptying, i.e., the slope of the exponential regression. Specific rate of emptying was independent of animal size, but increased with temperature. Therefore, food has a longer period in which to be digested at low temperatures, which suggests that assimilation efficiency may increase.However, the assimilation efficiency of amphipods feeding on decaying maple leaves in the laboratory was only 10% and did not vary with temperature. Ingestion and egestion rates were measured in the laboratory by weighing amounts eaten and defecated. The turnover time of the contents of a full gut in the laboratory often agreed very well with turnover time measured in the field, i.e., the reciprocal of the specific rate of emptying, thus confirming the use of an exponential regression.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1981.tb01240.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Reply to comments by Exner and Davies on the use of a standpipe corer (1979)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 9 (1979), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1979.tb01488.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    The occurrence of benthos deep in the substratum of a stream (1974)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 4 (1974), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: 〈list xml:id="l1" style="custom"〉1The vertical distribution of the benthic fauna of the Speed River, Ontario, was studied over a 13-month period from October 1970 to October 1971. Various physical and chemical parameters of this interstitial environment were also measured.2Several new techniques for sampling the interstitial environment of rivers wert devised. These methods and their relative efficiencies are considered.3The validity of the terms ‘hyporheal’ and ‘hyporheic’ are discussed and the term ‘hyporheos’ is offered to replace the former.4A brief resume of interstitial sampling methods is given with comments on their limitations for sampling deep heterogeneous substrates.5Chemical parameters are thought to be more important in the control and distribution ofthe fauna than physical parameters.6It is suggested that many larvae of stream-dwelling chironomids have over-wintering stages when they penetrate deep into the substrate to: (a) actively feed on the trapped organic detritus; (b) follow an optimum temperature for development.7It is suggested that the shape of an organism determines its success as a hypo-rheic form and examples are given.8The numbers of animals oecurring in the sub-benthic populations are shown to be very large indeed. For the Speed River, estimates of between 184,760 and 797,960 animals/m^ are made for different times of the year. Dry weight biomass is estimated o t vary between 30 9 g and 253-2 g/m^ throughout the year.9Sub-benthic or hyporheic populations are shown to exist in at least three other Canadian rivers. Some ofthe animals found are shown to be common to two or more of these rivers.10The inefficiencies of many conventional benthic samplers in sampling the total biomass of certain streams with hyporheic populations is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1974.tb00094.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Laboratory experiments on factors affecting the activity of Gammarus pseudolimnaeus Bousfield (1975)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 5 (1975), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Factors such as current, light, food, substrate and time of year were found to influence the activity of specimens of Gammarus pseudolimnaeus maintained in stream tanks in the laboratory. Although there was seasonal variation, levels of diurnal and nocturnal activity were generally much higher when there was no current than when the water was running. Diurnal periodicity occurred but was not as pronounced as had been indicated in the field studies of previous workers. Although there was activity during the day, nocturnal levels were higher especially in specimens collected during the summer. When there was no current, and the lights were left on for 24 h, peak activity occurred at precisely the times when the lights normally would have been off. This strongly suggests that there is an endogenous component in the activity. The nocturnal activity showed a bigeminus pattern, and there was a seasonal change, with the general activity at its highest levels in summer. Activity was significantly greater during daylight both with and without current when there was no substrate present in the tanks. The behaviour of Gammarus appears to be complex and greatly influenced by combinations of the various factors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1975.tb00154.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Biology of Plecoptera (1976)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Entomology 21 (1976), S. 135-153 
    Details
    ISSN: 0066-4170
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.en.21.010176.001031
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    The Ecology of Stream Insects (1970)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Entomology 15 (1970), S. 25-42 
    Details
    ISSN: 0066-4170
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.en.15.010170.000325
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A survey of the fauna of streams on Mount Elgon, East Africa, with special reference to the Simuliidae (Diptera) (1971)
    Oxford, UK : Blackwell Publishing Ltd
    Freshwater biology 1 (1971), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The stream fauna of Mt Elgon is described from collections taken during a 6-week visit. Collections were mainly made on the cultivated slopes below the belt of montane forest, and although stations were concentrated on the western sides of the mountain sufficient were worked elsewhere to show that there was little or no geographical variation of the fauna.The streams are physically diverse but faunistically rather uniform, with a few genera dominating the fauna throughout the entire range of altitude investigated. Most of the other taxa showed evidence of altitudinal limitation which may be attri-buted to the pronounced temperature gradients of the mountain's streams.As the species of Simuliidae and adult Elminthidae could be reliably distinguished their distributions were studied in greater detail. The Simuliidae showed a pronounced zonation of species, the majority being confined to narrow ranges of altitude below the forest margin. Factors considered to influence their distribution were principally altitude (temperature), current speed and, to a lesser extent, stream size. The influence of these factors on the distribution of adult Elminthids was less marked, although all species showed at least an upper or a lower limit of altitude, and more than half the commoner species a preference for a particular stream type.Taxonomic knowledge of African freshwater faunas allows few groups to be identified beyond the genus, and with this limitation the Elgon stream fauna is found to differ in only minor respects from the faunas of other highland areas in Central Africa.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2427.1971.tb01560.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Distribution of British Freshwater Amphipoda (1951)
    [s.l.] : Nature Publishing Group
    Nature 167 (1951), S. 152-153 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Eucrangonyx gracilis (S. I. Smith), a North American species, was first reported in Britain from Lea Bridge waterworks by Crawford1, and has since been recorded by Bassindale2 and Reid3, from the Avon and other places in the Midlands, Oxford, Surrey and Middlesex. I have recently found it in large ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/167152a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Selective Effect of Particulate Insecticides on Simulium among Stream Fauna (1965)
    [s.l.] : Nature Publishing Group
    Nature 208 (1965), S. 199-199 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The community of creatures living in fresh-water streams is highly organized and stable and constitutes many food chains, one ending in fish. The use of soluble DDT necessitates repetition and produces an entirely different organization, the maintenance of which is dependent on the maintenance of ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/208199b0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...