SCIENCE FINDINGS

Interior Columbia Basin Ecosystem Management Project ††††††††March 2000


These science findings were released in 1996 by the Projectís Science Integration Team.They were used by the Environmental Impact Statement Team in the development of the Draft and Supplemental Draft Environmental Impact Statements.

 

Overall Findings

* Some forest types are susceptible to severe fires due to accumulation of woody biomass.

* Forests with large, old trees have declined largely due to commercial harvest.

* Aquatic biodiversity has declined.There are increased threats to riparian‑associated species.

* Watershed disturbances (natural or human induced) cause risks to ecological integrity.

* Rangeland health and diversity have declined due to exotic species and increasing juniper and

†† conifer encroachment.

 

 


Landscape Conditions-

*In the last 100 years there have been increases in fire suppression costs, hazards, and fireseverity.

*In the last 100 years there have been decreases in native grasslands, shrublands, large residual trees, large snags and old forests due to human uses of land and resources.

*Greatest change in landscape conditions has occurred in areas associated with agriculture, human residences, roading, intensive logging and excessive livestock grazing.

* Changed vegetation patterns have increased susceptibility to severe fire and insect and disease disturbances of forests.

*Recent levels of management are unlikely to reverse undesired trends in landscape patterns and watershed conditions.Reversal will require a combined conservation and restoration strategy.

 

Terrestrial Ecosystems-

*Species that show declining trends are those associated with old forest structures, and shrublands, and grasslands.

*Habitat degradation is more pronounced in lower elevation watersheds due to human influences that have altered disturbance and hydrologic regimes.

*Habitat remnants and ecological processesremain for rebuilding and maintaining functional terrestrial ecosystems.

*Centers of biodiversity and hot spots of rare, native species are identified.

*Some threatened or endangered species are dependent on habitat components not evaluated at the Basin level;they can only be addressed through site and watershed analysis.

*Exotic plants (noxious weeds) are a significant threat to rangelands.

Aquatic Ecosystems-

* Key salmon species have experienced declines in habitat and abundance. These species are especially vulnerable at certain stages of their life cycle.

*Anadromous species have declined the most.Even if habitat stabilizes, fragmentation, isolation, and non‑habitat threats put remaining populations at risk.

*Habitat degradation is greatest in lower watersheds.

*Core remnants and ecological processes remain for rebuilding and maintaining functioning systems.

 

Social Conditions-

*Overall scenic quality is high.

*Communities located in moist climates have higher resiliency.Conversely, communities in drier climates have fewer economic options and are less resilient.

*Ecosystem management requires strong cooperation among local governments and agencies.

*People interpret ecosystem management differently, the concepts are still evolving.

 

Economic Conditions-

*Regional economies are experiencing growth,especially metropolitan and recreation counties.

*Regional economies are diverse and have high resiliency.At the county level, economic resiliency varies.Over half of the counties have low resiliency.

*Recreation on federal lands is highly valued.

*On National Forest System and BLM lands, timber, grazing, and recreation uses are important to local and regional economies.