Primary purpose
To assess whether a riparian-wetland area is functioning properly. Designed for use by the Bureau of Land Management (BLM) in conjunction with an initiative to restore and maintain riparian-wetland areas on BLM-managed lands.
Expertise needed
Interdisciplinary (ID) team including a biologist and specialists in vegetation, soils, and hydrology.
Applicable habitat types
Riparian-wetlands in the United States.
Categories assessed
Proper functioning condition.
Procedure
An interdisciplinary (ID) team reviews existing PFC documents, analyzes the PFC definition to identify benefits that are applicable to the study area, and begins to assess functionality by identifying applicable attributes/processes. The ID then visits each riparian-wetland area to determine the area’s condition through the approach outlined in Prichard et al. (1993, 1994) or a more detailed inventory effort. Users complete a standard checklist that (a) identifies 17-20 elements, (b) provides columns for checking yes, no, or not applicable for each element, (c) includes blank space for remarks on elements with a "no" response, and (d) includes a summary to record functional rating (e.g., proper functioning condition), trend for functional-at risk, and factors contributing to unacceptable conditions outside BLM’s control or management. Other ratings that may be defined when applying PFC to a management plan include: potential natural community (PNC) and desired plant community (DPC).
Key Terminology
Capability: the highest ecological status a riparian-wetland area can attain given political, social, or economical constraints (or limiting factors).
Desired plant community (DPC): plant community identified as "desired" based on management objectives.
Functional-at risk: riparian-wetland areas that are in functional condition but an existing soil, water, or vegetation attribute makes them susceptible to degradation.
Nonfunctional: riparian-wetland areas that clearly are not providing adequate vegetation, landform, or large woody debris to dissipate stream energy associate with high flows and thus are not reducing erosion, improving water quality, etc.
Potential: the highest ecological status an area can attain given no political, social, or economical constraints; often referred to as the "potential natural community (PNC)".
Potential natural community (PNC): the highest ecological status an area can attain given no political, social, or economical constraints.
Potential plant community (PPC): represents the seral stage the botanical community would achieve if all successional sequences were completed without human interference under the present environmental conditions.
Proper functioning condition (PFC): Riparian-wetland areas are functioning properly when adequate vegetation, landform, or large woody debris is present to dissipate stream energy associated with high waterflows, thereby reducing erosion and improving water quality; filter sediment, capture bedload, and aid floodplain development; improve flood-water retention and ground-water recharge; develop root masses that stabilize streambanks against cutting action; develop diverse ponding, and channel characteristics to provide the habitat and the water depth, duration, and temperature necessary for fish production, waterfowl breeding, and other uses; and support greater biodiversity. The functioning condition of riparian-wetland areas is a result of interaction among geology, soil, water, and vegetation.
Contact person
Don Prichard, Bureau of Land Management, National Applied Resource Sciences Center, Denver Federal Center, Building 50, P.O. Box 25047, Denver, CO 80225-0047 phone: (303) 236-0162; fax: (303) 236-3508; e-mail: dprichard@sc.blm.gov
Output
Rating of proper functioning condition of a site.
Estimated time to assess 1 acre site
Total 9-25 hours.
8-24 hours per study area: Review existing documents (step 1) and analyze definition of PFC (step 2).
Less than 1 hour per wetland-riparian area: Assess functionality (step 3).
Comparison of habitat types
Can directly compare wetlands (from the same or different wetland class) within same or different geographic area.
Use as guide to design
PFC is not intended as a design tool, but can be used as a guide to develop management strategies. For example, PFC does not provide validated threshold values for many variables. Another aspect to consider is whether the variables can provide explicit design criteria. The design criteria under the hydrologic category would not be explicit (e.g., # 2: design for a fluctuation of water levels that is not excessive). Some of the variables may provide useful information. Users can refer to the variables to determine which conditions increase or decrease function (e.g., # 4: consider the upland watershed and whether it contributes to riparian-wetland degradation).
Related procedures
None.
Extent of use/field testing
PFC has been extensively used by the US Forest Service and the Bureau of Land Management (BLM) to assess the condition of riparian-wetland areas on public lands. BLM has used PFC on 40,000 miles of stream and 150,000 acres of lentic wetland areas during 1993-1996. Estimates for the last two years are not available. The Natural Resources Conservation Service (NRCS) is also using PFC to assess riparian-wetland areas on private land (Pers. comm.: D. Prichard, BLM, June 12, 1998). The extent of use over the last two years by the Forest Service and NRCS is unknown.
Proposed future revisions
PFC was updated in 1998, so there are no current plans for revisions.
Key References
Prichard, D., H. Barrett, J. Cagney, R. Clark, J. Fogg, K. Gebhart, P.L. Hansen, B. Mitchell, and D. Tippy. 1993. Riparian Area Management: Process for Assessing Proper Functioning Condition. TR 1737-9 (Revised 1998). Bureau of Land Management,BLM/SC/ST-93/003+1737+REV95+REV98, Service Center, CO. 51 pp.
Prichard, D., C. Bridges, R. Krapf, S. Leonard, and W. Hagenbuck. 1994. Riparian Area Management: Process for Assessing Proper Functioning Condition for Lentic Riparian-Wetland Areas. TR 1737-11. Bureau of Land Management, BLM/SC/ST-94/008+1737, Service Center, CO. 37 pp.
Additional references
Clemmer, P. 1994. Riparian Area Management: The Use of Aerial Photography to Manage Riparian-Wetland Areas. TR1737-10. Bureau of Land Management, BLM/SC/ST-94/005-1737, Service Center, CO. 64 pp.
Gebhardt, K., S. Leonard, G. Staidl, and D. Prichard. 1990. Riparian Area Management: Riparian and Wetland Classification Review. Bureau of Land Management, BLM/YA/PT-91/002+1737, Service Center, CO. 56 pp.
Leonard, S., G. Staidl, J. Fogg, K. Gebhardt, W. Hagenbuck, and D. Prichard. 1992. Riparian Area Management: Procedures for Ecological Site Inventory—With Special Reference to Riparian-Wetland Sites. Bureau of Land Management, BLM/SC/PT-92/004-1737, Service Center, CO. 135 pp.
Myers, L.H. 1989. Riparian Area Management: Inventory and Monitoring of Riparian Areas. Bureau of Land Management, BLM/YA/PT-89/022+1737, Service Center, CO. 89 pp.
Prichard, D., P. Clemmer, M. Gorges, G. Meyer, and K. Shumac. 1996. Riparian Area Management: Using Aerial Photographs to Assess Proper Functioning Condition of Riparian-Wetland Areas. TR 1737-12. Bureau of Land Management, BLM/RS/ST-96/007+1737, National Business Center, CO. 37 pp.