9446

• UCREFRP Catalog Number: 9446
• Author: Stanford, J. A., J. V. Ward, W. J. Liss, C. A. Frissell, R. N. Williams, J. A. Lichatowich and C. C. Coutant
• Title: A General Protocol for Restoration of Regulated Rivers
• USFW Year: 1996
• USFW - Doc Type: Regulated Rivers
• Copyright Material: YES

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J, A, STANFORD ET AL.

FLOODPLAIN

HILLSLOPE I

TERRACE

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Pioneer

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Upland Forest

Climax
Riparian Forest

Channel

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Figure I, Major landscape features of a montane floodplain river, showing the three primary spatial dimensions (lateral, longitudinal or
altitudinal, and vertical) that are dynamically molded through time (the fourth dimension) by fluvial processes, Biota may reside in all
three spatial dimensions: riparos (streamside or riparian), benthos (channel), hyporheos (river-influenced groundwater) and phreatos
(deep groundwater). The hatched area is the varial zone or the area of the channel that is periodically dewatered as a consequence of
the average amplitude of the discharge regime. Major channel features include a run (A), riffle (B) and pool (C); Sd refers to sites of
sediment deposition and Se refers to a major site of bank erosion. The heavy solid line is the thalweg and broken lines conceptualize
circulation of water between benthic, hyporheic and phreatic habitats (after Stanford, 1996; see also Stanford and Ward, 1992)

GENERAL PRINCIPLES OF RIVER ECOLOGY

Conservation and management strategies for large rivers must have a solid conceptual basis or they will
likely fail to sustain biodiversity and bioproduction, Contemporary river ecology is guided by a number
of intertwined concepts or principles derived from empirical studies. No two rivers are exactly alike and
no single theory encompasses the myriad of biophysical interactions and responses to natural and human
disturbances that make each river unique, However, fundamental principles do apply; many conservation
and restoration efforts become myopic, costly and too often fail because plans and actions overlook ecolo-
gical fundamentals.
Unregulated rivers exist as geohydraulic continua from continental divides to the oceans. They are net-
works of surface and groundwater flow paths that drain catchment landscapes (Gibert et at., 1990), The
energy of flowing water constantly reconfigures the physical form of these interconnected flow pathways,
primarily by the process of cut and fill alluviation (Leopold et at" 1964) although dissolution can dominate
in limestone massifs (Mangin, 1994) and a few other situations, Inorganic and organic materials are eroded
upstream and deposited downstream primarily in relation to: (a) long- and short-term flow dynamics; (b) the
resistivity of geological formations to erosion and dissolution; (c) instream retention structures (e.g. eddies,
wood debris); and, (d) the geometry of the catchment.
Channel morphologies are determined by the legacy of flooding. Big floods fill channels with inorganic
and organic materials eroded laterally and vertically at upstream locations, thereby producing a continuum
of instream structures (pools, runs, riffles, gravel bars, avulsion channels, islands, debris jams) and lateral
floodplain terraces in many sizes and shapes, Local morphologies resulting from infrequent, very large floods
may persist in the same general form (quasi-equilibrium) for long time periods until the next big flood, even