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Braided A channel planform in which individual channels branch and rejoin
downstream around bars and islands that commonly have relatively little woody
riparian vegetation
Catchment See drainage basin
Channel maintenance flows Components of a river flow regime necessary to
maintain specific channel characteristics, such as cross-sectional area for flood
conveyance
Channel migration zone The width of the valley bottom across which channels
can migrate and have migrated under the contemporary flow regime
Characteristic form time Describes the persistence of a feature within a river
relative to the recurrence interval of the flow that creates the feature; a transient
form is created by a disturbance, but then modified to pre-disturbance conditions
before the recurrence of a disturbance of similar magnitude; a persistent form
is present longer than the recurrence interval of the flood that created the form
Complexity Spatial heterogeneity, or the degree to which a river corridor deviates
from a straight, uniform canal
Complex response A nonlinear geomorphic response to a single external change
such as a large flood, change in land cover, or drop in base level
Connectivity The transfer of materials (e.g., water, sediment), energy, and organisms between components of a system; commonly described for rivers with
respect to longitudinal, lateral, and vertical dimensions
Context The environmental setting of the river corridor; the climate and precipitation regime, geology, topography, biome, position in the river network, land use,
and land use history
Development space In the context of water-resource development, development
space is the difference between current conditions in a river network and the
furthest level of water-resource development found acceptable to stakeholders
through consideration of diverse scenarios of water development
Direct alterations (of rivers) Human activities undertaken within the river network and which affect river corridor configuration and connectivity, as well as
water and sediment regimes
Disturbance Any relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or
the physical environment
Disturbance regime The spatial pattern and statistical distribution of disturbances
with respect to magnitude, frequency, and duration of associated changes in the
physical environment
Downstream hydraulic geometry Conceptual model in which discharge is the
dominant control on channel geometry and channel parameters such as width,
depth, and velocity change progressively downstream as discharge increases
Drainage basin For any designated point, all of the river network and adjacent
landscape that drains to that point; used synonymously with catchment and
watershed
Glossary
Braided A channel planform in which individual channels branch and rejoin
downstream around bars and islands that commonly have relatively little woody
riparian vegetation
Catchment See drainage basin
Channel maintenance flows Components of a river flow regime necessary to
maintain specific channel characteristics, such as cross-sectional area for flood
conveyance
Channel migration zone The width of the valley bottom across which channels
can migrate and have migrated under the contemporary flow regime
Characteristic form time Describes the persistence of a feature within a river
relative to the recurrence interval of the flow that creates the feature; a transient
form is created by a disturbance, but then modified to pre-disturbance conditions
before the recurrence of a disturbance of similar magnitude; a persistent form
is present longer than the recurrence interval of the flood that created the form
Complexity Spatial heterogeneity, or the degree to which a river corridor deviates
from a straight, uniform canal
Complex response A nonlinear geomorphic response to a single external change
such as a large flood, change in land cover, or drop in base level
Connectivity The transfer of materials (e.g., water, sediment), energy, and organisms between components of a system; commonly described for rivers with
respect to longitudinal, lateral, and vertical dimensions
Context The environmental setting of the river corridor; the climate and precipitation regime, geology, topography, biome, position in the river network, land use,
and land use history
Development space In the context of water-resource development, development
space is the difference between current conditions in a river network and the
furthest level of water-resource development found acceptable to stakeholders
through consideration of diverse scenarios of water development
Direct alterations (of rivers) Human activities undertaken within the river network and which affect river corridor configuration and connectivity, as well as
water and sediment regimes
Disturbance Any relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or
the physical environment
Disturbance regime The spatial pattern and statistical distribution of disturbances
with respect to magnitude, frequency, and duration of associated changes in the
physical environment
Downstream hydraulic geometry Conceptual model in which discharge is the
dominant control on channel geometry and channel parameters such as width,
depth, and velocity change progressively downstream as discharge increases
Drainage basin For any designated point, all of the river network and adjacent
landscape that drains to that point; used synonymously with catchment and
watershed
Glossary