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