By Will Walker – ASWM – September 2011

Wetlands are dynamic, living systems subject to a broad array of changes on a variety of time scales.  Rivers change their course as a result of ongoing erosion and deposition; shrub scrub wetlands grow into forested wetlands; beavers create impoundments that expand wetlands; and human activities can destroy or restore wetlands.  In order to be effective tools for wetland managers, information about wetlands needs to stay current and reflect forces like succession and especially human alteration of the landscape. Good data have high predictive value and help planners, wetland managers and other program managers to focus their efforts.  Mapping products designed with accurate, regularly updated data can reduce the costs associated with conserving, regulating and protecting wetlands.

In 2010 the Association of State Wetland Managers (ASWM) set out to take a snapshot of the status of wetland mapping in the United States.  ASWM staff produced documents summarizing the age and extent of wetland maps for each state using the U.S. Fish and Wildlife Service’s  National Wetlands Inventory (NWI) dataset from January 2010.
To read full article, click here.