Library

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
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 21 (1985), S. 0 
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: A system is proposed to classify running water habitats based on their channel form which can be considered in three different sedimentological settings: a cobble and boulder bed channel, a gravel bed channel, or a sand bed channel. Three physical factors (relief, lithology, and runoff) are selected as state factors that control all other interacting parameters associated with channel form. When these factors are integrated across the conterminous United States, seven distinct stream regions are evident, each representing a most probable succession of channel forms downstream from the headwaters to the mouth. Coupling these different channel profiles with typical biotic community structures usually associated with each of the channel types should result in considerable refinement of the applicability of the River Continuum Concept and other holistic ecosystem models by realizing the nonrandomness of the effects of geo-morphology on stream ecosystems. Thus, this regional perspective of streams should serve to make persons concerned with water resources more aware of the geographical considerations that affect their study areas.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 220 (1991), S. 99-108 
    ISSN: 1573-5117
    Keywords: stream ; benthic invertebrates ; distribution ; channel form ; disturbance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Benthic species assemblages in upstream and downstream ends of riffles and in pools were investigated seasonally in the first five orders of an alluvial gravel stream with distinct pool and riffle channel form. Riffles comprised 〈 10% of stream area and were separated by pools with extensive bedrock substrate (ca. 15–85% of total surface area) which was scoured during periodic high flow. Virtually all taxa were more abundant in riffles than in pools, except chironomids which were more equally distributed. Inconsistent results were obtained for upstream-downstream comparisons within riffles. Intermittent headwater reaches (orders 1 & 2) which supported half as many taxa retained this pattern during periods of flow, although riffles at these sites were dry from mid-June to mid-November. Pools which contained more gravel, indicating less disturbance during high flow, had a richer assemblage of benthic species than other pools. Many invertebrates in pools may have been there as a result of drift from their preferred riffle habitats, but the presence of gravel in the pools indicates less intense flow disturbance during floods, provides protection from the mild scouring that does occur during floods, and provides refugia from predators.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 220 (1991), S. 109-117 
    ISSN: 1573-5117
    Keywords: stream ; benthos ; distribution ; functional groups ; riffle-pool ; channel form
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An Ozark Plateau stream was studied to determine the influence of distinct pool and riffle geomorphology on the longitudinal zonation of macroinvertebrate species assemblages and functional group classification. All study sites were dominated by alluvial pool and riffle channel form and the first two orders became intermittent during summer months. Nine benthos samples were collected seasonally from riffles and pools at each of five sites using a vacuum benthos sampler. Diel temperature pulse and coarse particulate organic matter (CPOM) were measured at each site also. Water temperature was most variable in second order, and CPOM on riffles was not more abundant in upstream reaches. Annual average density and biomass of invertebrates were highest in third and fourth orders, respectively. Diversity was depressed in the intermittent headwaters sites. Macroinvertebrate functional groups did not exhibit strong longitudinal trends as predicted by the river continuum model, with species assemblages apparently more strongly affected by the segment-level physical template, although shredders were more abundant in the headwaters during fall and winter. This study indicates that a reach-level perspective based on channel form is a necessary complement to holistic stream ecosystem models, especially in alluvial gravel streams.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...