Great Ideas in Riverine Ecology
Linear to Landscapes
FISH 7380; Dr. E. Irwin
Geology and climate(present and historical)
River MorphologyHydrology
Sediment transportNutrient/elemental availability
Basin flora and faunaTerrestrial communities
Systems created by water running downhill depend on:
Carbon/solarinput
Patterns of flows = community function4) spiraling and retention5) connectedness6) biotic/abiotic controls
Human interference
1) stream classification
2) longitudinal processes3) Riparian-river interactionsLand use
heterotrophybiota
Trophic structure Habitat structure
Classification Streams can be classified Allows managers and scientists to organize
river systems Conceptual and regional approaches
Climate and geology, but vegetation important also
NA-Ecosystem approach (broad scale) Climate, physiography and vegetation
Hierarchical classification Spatially nested
levels of resolution
Problem—relatively distinct boundaries
Stream Order Strahler (1952) and
modified by Horton (1945)
Variation from headwaters to mouth
Ordering gives a measure of position
Others-link magnitude, d-link
Longitudinal Zonation
River Continuum Concept
Downstream transfers of energy and matter
Invertebrate functional groups
US—DS in lowland rivers=lateral exchanges and vertical fluxes
River-Riparian Interactions Allochtonous
inputs, LWD Flood-pulse
concept Annual floods
drive organic matter and nutrient input in large floodplain rivers.
Lateral and vertical bounds revisited
Longitudinal, lateral and vertical fluxes
Spiraling and Retention
Connectedness
Disturbance Other abiotic
controls Biotic?
Limiting resources
Abiotic and Biotic Control
Disturbance-structures stream communities
High/low flows Especially in headwaters
Pressure Points Interference: how
management can mess things up.
Discontinuity- Serial Faunal