Friday, February 3, 2012

Restoring and Creating Wetlands? The Envelope, Please

As the parent of one college-age daughter and one college-bound daughter, I could say I took the semester off from posting entries to the blog or I could just get down to business. The latter.

Last week an entry in the New York Times blog on energy and the environment, click here, reported on an article (click here) released earlier that week on the Public Library of Science Biology ("PLOS Biology") website, a peer-reviewed open-access journal published online. The article reported on what the authors characterize as only partial success of restoration and creation of wetlands in the 20th century, by examining 621 wetlands systems worldwide, comparing those impaired or recovering sites to 556 functioning/unimpaired wetland sites.

The article, "Structural and Functional Loss in Restored Wetland Ecosystems," was authored by scientists from California, Spain and France. Some trends that were noted: large wetlands areas (over 100 hectares) in warm climates recovered more rapidly than smaller areas in cold climates; riverine and tidal wetlands recovered more rapidly than isolated wetland segments.
The scientists reported that animals, such as birds, bats and flying insects (midges) returned within five years, while macroinvertebrates such as water fleas, returned within five to ten years.

They noted, however, that the population levels were neither as high nor as diverse.

The plant communities recovered the slowest, on average taking thirty years to recover. Again the plant populations remained less abundant and diverse, recovering to approximately 75% of prior condition. According to the authors, restoration can succeed but over longer timeframes and without complete recovery.

When the state wetlands law was amended in 1996, click here for Public Act 96-157, the legislature included explicit language regarding mitigation of wetlands impacts. Mitigation measures include activities to "prevent or minimize" pollution or damage, "maintain or enhance existing environmental quality." The legislature established a hierarchy of preferred activities, in order of priority: "restore, enhance and create productive wetland or watercourse resources." (This language is found in two sections of the statute: § 22a-41(a) (4) and § 22a-42a (d) (1).)

If the authors of this recently reported article in PLOS Biology site are correct, perhaps "restoring" should take a secondary position and "enhancing" or protecting current wetlands a primary one.

There's an opportunity soon to hear about the results of some local (CT) and regional (NY, MA) mitigation projects, that include relocation of a watercourse, wetlands creation, and other mitigation projects that have been monitored, at the CT Association of Wetlands Scientists' annual meeting on March 22, 2012. Click here for an agenda and online registration.

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