Considerations in Selecting an Approach to Assessing Wetland Function

Abstract

Many approaches and specific procedures have been developed to assess wetland function for regulatory, planning, management, and education purposes. General approaches include descriptive narratives based on best professional judgment, application of classification systems (e.g., USFWS classification), sampling of specific structural or functional criteria (e.g., bird survey), and the application of wetland assessment procedures (e.g., Habitat Evaluation Procedure, Hydrogeomorphic Approach, and Index of Biological Integrity). The task of identifying the best approach can be difficult depending upon the complexity of the study and whether there are multiple objectives. This paper identifies the various considerations in choosing an approach and outlines steps to selecting a wetland assessment procedure. This process is illustrated with an example of a large scale project, involving the assessment of several existing wetland areas and proposed wetland restoration. The example demonstrates that in many cases no one procedure can meet all study objectives. It is recommended that the overall objectives be clearly stated at the beginning and that a variety of procedures be considered. Several approaches, including a combination of models from different procedures, may be needed to meet all objectives throughout the different stages of study.