20- Lecture River and
Watershed Management
Freshwate
r
Ecosyste
ms
EVPP/BIO River Ecology and Management: Lessons from the
Source lecture material:
Pacific Coastal Ecoregion. 1998. Naiman, R. J. and R. E. Bilby (eds). Springer-
Environmental
change
During the past two centuries, human activities
have become the principal driver of change on
earth
Human-caused change may be positive, neutral
or negative
Resource and environmental managers want to
detect and treat changes that have negative
consequences; they also want to avoid wasting
resources
Environmental Health of
Rivers
Changes anywhere on the landscape are likely
to influence rivers
Examples are:
- Harvesting forests
- Constructing flood control measures
- Mining for minerals
- Constructing industrial parks, shopping
centers,
homes and roads
- Converting land for agriculture
Biological Integrity of Rivers
Biological integrity is the capacity to
support and maintain a balanced,
integrated, and adaptive biological system
having the full range of elements and
processes expected in a regions natural
habitat
Human impact
When humans modify landscapes or
stream channels, changes in biological
integrity are likely
Human actions can jeopardize the
biological integrity by altering one or more
principle factors:
- physical habitat
- seasonal flow of water (hydroperiod)
- the food base of the system
Disturbances
Systems possessing biological integrity can
withstand, or recover rapidly from, most natural
disturbances
Biological integrity declines if the natural
disturbance regime is altered by perturbation
that lies outside the biotas adaptive experience
Especially when disturbances
become incessant
Disturbances
Biological monitoring
Biological monitoring is the most practical and
cost-effective approach to determine if human
actions are degrading biological integrity
Four major measurement approaches commonly
used to detect the effects of human actions:
- Indicator taxa or guilds
- Species richness, diversity and evenness
- Multivariate statistics
- Multimetric indices such as IBIs
Sampling design
Compared with physical or chemical
parameters, biological parameters have a
high natural variability (noise)
Statistics are very important when
interpreting biological data
Just comparing an impacted area with a
control area (or one area before and after
impact) is not enough
A BACI-design (and improvements on this
Sampling design
The Use of
Statistical
Methods
Multivariate statistics
are used to detect
distribution patterns in
data
Multi Dimensional Scaling (MDS) plot
De Mutsert and Cowan, in press
pH
plant sp.
SAV
plant (g)
# Stem
DO
Temp
Turb Depth
Sal
Canonical Correspondence Analysis
And to determine how
environmental data and
biological data are linked
The Index of Biological Integrity
Developed by Karr (1981)
Was the first comprehensive multimetric
index applied to assess biological
condition in running waters
Developed for fish assemblages, later
successfully adapted for benthic
invertebrate communities
The Index of Biological Integrity
When developed and used properly, IBIs
can:
- Detect degradation of living systems
- Diagnose the likely causes of degradation
- Identify management actions that can halt or
reverse degradation
- monitor living systems to find out if
management efforts to restore degraded sites are
successful
The Index of Biological Integrity
The Index of Biological Integrity
Successful application of multimetric
biological indices requires four tasks:
- Selecting measurable attributes that provide
reliable and relevant signals about the effects of
human activities
- Developing sampling protocols and designs
that ensure that those attributes are measured
accurately
Watershed Management
Management at the watershed scale is a
major challenge, but may be the
appropriate scale to achieve results
Watershed Management: can
be hard to implement
Watershed Management: can
be hard to implement
Watershed Management
Scale
Watershed-scale activities must ultimately
be integrated across a larger region
However, since peoples interests,
commitments and knowledge are
generally localized, regulation by local
organizations can sometimes be most
effective
Communication between local initiatives is
important
Fundamental principles to make
watershed management work
Recognize that watershed management
demands unparalleled cooporation among
citizens, governmental agencies, private
institutions, and academic organizations
The complexity of information processing and
the scope of socioenvironmental change
exceeds the capacity of any single group to
manage a watershed effectively
Fundamental principles to make
watershed management work
Balance technical solutions (e.g. fish hatcheries,
waste management) to specific humangenerated problems with the wide-scale
maintenance of appropriate environmental
components that provide ecological services
Fundamental principles to make
watershed management work
Minimize decisions based only on
conceptualization and perception; data-driven
policy and management need decisions to be
the standard for resolving issues
Fundamental principles to make
watershed management work
Apply regulations guiding the structure and
behavior of the socioenvironmental system
evenly and fairly throughout the watershed.
Basic regulations (such as riparian protection
and chemical applications) should not differ
across forestry, agricultural, and urban areas but
should encourage citizen initiatives and
landowner incentives that results in greater
protection and reduced chemical application
Fundamental principles to make
watershed management work
Accept human activities as fundamental
elements of the watershed along with the
structure and dynamics of the environmental
components. Both have inherent rights to exist
for the long term
Stream and Watershed
Restoration
Restoration is the process of returning a river or
watershed to a condition in which it can function
ecologically in a self-sustaining way, more nearly
resembling its former function prior to humaninduced disturbance
Stream and Watershed
Restoration
The process has changed from small-scale
artificial structures (e.g. fish ladders) or
modifications (e.g. add fish from hatcheries) to
regional and watershed-scale reestablishment of
the biophysical processes and structures that
promote natural ecosystem recovery
Stream and Watershed
Restoration
To be able to restore a watershed, cause and
effect relationships of processes operating at an
(overwhelmingly) large scale need to be
understood
The magnitude and extend of environmental
change that has occurred in the watershed
needs to be appreciated
Learn from previous attempt: The ecological
success or failure of contemporary stream and
watershed restoration needs to be accurately
documented
Stream and Watershed
Restoration
The principal effect of human disturbance is to
alter or suppress key successional stages,
thereby eliminating certain desirable
characteristics of diversity that the ecosystem
would otherwise include
Restoration measures should not focus on
directly recreating natural structures or states,
but on identifying and reestablishing the
conditions under which natural states create
themselves
The focus should be on ecosystem processes
Monitoring recovery
Until recovery trends are manifested in some
self-sustaining, relatively naturally functioning
condition, restoration or recovery has not truly
occurred
When resources committed to monitoring and
evaluating are insufficient, new projects fail to
receive the potential benefit of knowledge
gained from adequate analysis of past mistakes
and successes
Watershed-Scale Restoration
Case Study
The watershed-scale restoration project at
Redwood Creek Basin, Redwood National
Park, California
Redwood Creek Basin
The restoration program did not begin as an
effort focused on fish, but had the broader goal
to restore natural watershed and stream channel
processes
Experimental efforts focused on upslope erosion
sources which are the principal and continuing
cause of problems in the stream channel
Redwood Creek Basin
A combination of different restoration efforts was
applied
It started with assessment of condition by
physical as well as biological scientists to
determine what was at the root of the problem
Acknowledging the experimental nature, teams
of physical and biological scientists designed
and executed an extensive monitoring and
evaluation effort
Redwood Creek Basin
Most projects were geared toward reducing
potential sediment sources to streams, but there
were small local projects added within the larger
framework
Construction and modification projects using
heavy equipment and hand labor were involved
If sufficient care was taken during equipment
operations, park staff found they could rely
largely on natural revegetation continuing the
restoration
Long-term monitoring
Long-term monitoring is the most practical and
effective way to assess a restoration program
and document the recovery of ecosystems
A reference area is important again: this time to
assess the unrestored condition of a river to
gauge the effect of restoration efforts on your
treatment river
Adaptive Ecosystem
Management
Predicting the outcome of restoration
efforts at the scale of a whole watershed is
highly problematic due to the diffuse,
persistent, and time-dependent nature of
cumulative effects operating within a basin
The best approach is to implement a
sound adaptive management plan
Announcements
Volunteer opportunity:
Become an Arlington Stream Monitor
Training offered January 12 from 7-9 p.m.
Stream monitors visit a monitoring site four
times a year with their team and collect
data on the health of Arlington's streams.
After attending the training, you will have
the opportunity to join a team to monitor a
local stream site.
Announcements
Bring #2 pencil, black or blue ink, to fill out
evaluation forms on Monday December 5
We will receive a herbarium tour from Dr. Andrea
Weeks on Friday Dec 2. We will meet in the lab
and walk over; arrive on time
It is now time for the wetland presentation!