March 1, 2011
Journal Article

A Levels-of-Evidence Approach for Assessing Cumulative Ecosystem Response to Estuary and River Restoration Programs

Abstract

Even though large-scale ecological restoration programs are beginning to supplement isolated projects implemented on rivers and tidal waterways, the effects of restoration success often continue to be evaluated at project scales or by integration in an additive manner. Today our scientific understanding is sufficient that we can begin to apply lessons learnt from assessing cumulative impacts of anthropogenic stressors on ecosystems to the assessment of ecological restoration. Integration of this knowledge has the potential to increase the efficacy of restoration projects conducted at several locations but co-managed within the confines of a larger integrative program. We introduce here a framework based on a levels-of-evidence approach that facilitates assessment of the cumulative landscape effects of individual restoration actions taken at many different locations. It incorporates data collection at restoration and reference sites, hydrodynamic modeling, geographic information systems, and meta-analyses in a five-stage process: design, data, analysis, synthesis and evaluation, and application. This framework evolved from the need to evaluate the efficacy of restoration projects designed to increase rearing habitat for outmigrating juvenile salmonids, which are being implemented in numerous wetlands on the 235-km tidal portion of the Columbia River, U.S.A.

Revised: April 27, 2011 | Published: March 1, 2011

Citation

Diefenderfer H.L., R.M. Thom, G.E. Johnson, J.R. Skalski, K.A. Vogt, B.D. Ebberts, and G.C. Roegner, et al. 2011. A Levels-of-Evidence Approach for Assessing Cumulative Ecosystem Response to Estuary and River Restoration Programs. Ecological Restoration 29, no. 1-2:111-132. PNNL-SA-55734.