Virginia Tech
    • Log in
    View Item 
    •   VTechWorks Home
    • College of Science (COS)
    • Department of Biological Sciences
    • Faculty Works, Department of Biological Sciences
    • View Item
    •   VTechWorks Home
    • College of Science (COS)
    • Department of Biological Sciences
    • Faculty Works, Department of Biological Sciences
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    The land-cover cascade: Relationships coupling land and water

    Thumbnail
    View/Open
    Main article (191.4Kb)
    Downloads: 888
    Date
    2007-01
    Author
    Burcher, C. L.
    Valett, H. M.
    Benfield, E. F.
    Metadata
    Show full item record
    Abstract
    We introduce the land-cover cascade ( LCC) as a conceptual framework to quantify the transfer of land-cover-disturbance effects to stream biota. We hypothesize that disturbance is propagated through multivariate systems through key variables that transform a disturbance and pass a reorganized disturbance effect to the next hierarchical level where the process repeats until ultimately affecting biota. We measured 31 hydrologic, geomorphic, erosional, and substrate variables and 26 biotic responses that have been associated with land-use disturbance in third- and fourth-order streams in the Blue Ridge physiographic province in western North Carolina ( USA). Regression analyses reduced this set of variables to include only those that responded to land cover and/or affected biota. From this reduced variable set, hypotheses were generated that predicted the disturbance pathways affecting each biotic response following the land-cover-cascade design. Cascade pathways began with land cover and ended with biotic responses, passing through at least one intermediate ecosystem abiotic component. Cascade models were tested for predictive ability and goodness-of-fit using path analysis. Biota were influenced by near-stream urban, agricultural, and forest land cover as propagated by hydrologic ( e. g., discharge), geomorphic ( e. g., stream bank height), erosional ( e. g., suspended sediments), and depositional streambed ( e. g., substrate size) features occurring along LCC pathways, reflecting abiotic mechanisms mediating land-cover disturbance. Our results suggest that communities are influenced by land-cover change indirectly through a hierarchy of associated abiotic components that propagate disturbance to biota. More generally, the land-cover cascade concept and experimental framework demonstrate an organized approach to the generic study of cascades and the complex relationships between landscapes and streams.
    URI
    http://hdl.handle.net/10919/24800
    Collections
    • Faculty Works, Department of Biological Sciences [427]

    If you believe that any material in VTechWorks should be removed, please see our policy and procedure for Requesting that Material be Amended or Removed. All takedown requests will be promptly acknowledged and investigated.

    Virginia Tech | University Libraries | Contact Us
     

     

    VTechWorks

    AboutPoliciesHelp

    Browse

    All of VTechWorksCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    Log inRegister

    Statistics

    View Usage Statistics

    If you believe that any material in VTechWorks should be removed, please see our policy and procedure for Requesting that Material be Amended or Removed. All takedown requests will be promptly acknowledged and investigated.

    Virginia Tech | University Libraries | Contact Us