Restoration ecology
What is restoration ecology?
Fairly new field of science
Society for Ecological Restoration formed in 1987
Ecological restoration
Restoration: to bring back into a former or original state.
Rehabilitation: any repair of elements of structure or function
Reclamation: rehabilitation of severely degraded sites
Re-creation: reconstruction of a system that is so severely disturbed that nothing is left to restore
Ecological recovery: leaving a system alone, to recover on its own
Why has the use of restoration ecology grown over time?
Legislation requires restoration
Clean Water Act and wetland mitigation
Surface Mine Reclamation Act
Endangered Species Act
Growing interest in native landscaping
Sheer level of ecological destruction has made restoration necessary in many places
Endangered Species Act (ESA), 1973
Section 9 prohibits “take”of listed organisms, which includes harassing, harming, pursuing, hunting, shooting, wounding, killing, trapping, capturing, and collecting
Exception to “take” prohibition
Section 10(a): Private citizens can receive an“incidental take” permit if they develop a plan that compensates (“mitigates”) for the taking of individuals by promoting survival of the population or species in some other way
Restorationists...
…recognize that an ecological system has been altered by humans in some way and seek to reverse this influence
...make goal of restoration clear and measurable
…acknowledge that restoration is both an active and passive process.
…are committed to re-creation of entire system in all its aspects
Restoration ecology
Application of principles of evolution and ecology to returning habitat or ecosystems to their former condition
What are we trying to restore?
Ecological structure
Ecological function
Restoration is “returning to a close approximation of a system’s condition prior to disturbance, with both structure and function of the system recreated.” (National Research Council, 1992)
Approaches to restoration
Steps in restoration
Set a realistic, measurable goal
Determine a strategy and methods
Remove source of degradation
Restore the physical environment
Restore the biota
Monitor the restoration, assess success and adapt if necessary
Be patient
The iterative process
Setting goals
Clear and achievable goals are essential
Goals or targets may be set by reference areas, historical data, or compilation from many fragments of an idealized scenario:
Should be forward-looking:
Desired characteristics of system of future, not what existed in the past (“sensible goals”)
Should consider a range of options:
- implies societal evaluation of alternatives
Some steps in terrestrial restoration
Stabilize/reconstruct surfaces
Improve aesthetics
Reduce erosion
Steps in terrestrial restoration
Control pollution
Phytoremediation = using plants to remove toxins from soil
Steps in terrestrial restoration
Restore species
Reintroduction, succession, disturbance, invasive control, genetics, etc.
Restore function
Some steps in aquatic restoration
Restore water flow regimes
Reverse channelization
Reduce drainage
Levee breach at ConsumnesRiver
Steps in aquatic restoration
Control pollution
Buffer plantings control thermal pollution, nutrient enrichment and sedimentation
Restore species and function
Size of restoration
Project should be large enough to minimize deleterious effects of boundary conditions and internal dynamics
Project should be “manageable” size
Project should be affordable
Restoring vernal pools in CA
Shallow depression
Poorly drained due to impermeable soil layer
Water source is precipitation
Wet and dry phases
Historical information
“The Great Central Plain of California, during the months of March, April, and May, was one smooth continuous bed of honey-bloom, so marvelously rich that, in walking from one end of it to the other, a distance of more than 400 miles, your foot would press about a hundred flowers at every step… The radiant, honeyful corollas, touching and overlapping, and rising above one another, glowed in the living light like a sunset sky—one sheet of purple and gold…”
John Muir, The Mountains of California (1894)
Vernal pool construction and seeding: December 1999
Winter rains fill pools
Hydrology