New post on River Life

 

 

Restoring a River, 2,000 Trees at a Time

by Patrick Nunnally

It’s becoming an article of faith among many professionals that “ecological restoration” is impossible, or, at best, a lot more complex than we used to think.  The most recent culprit for the “impossible” argument is climate change, which can alter a region’s hydrology so thoroughly that other biological and physical processes are irreparably changed as well.

A recent “Earth Journal” column in MinnPost.com suggests there may be strong evidence for the “very difficult but not impossible” understanding of ecosystem restoration.  Writer Ron Meador interviewed Maria DeLaundreau, a Minnesota Green Corps participant hosted by the Mississippi River Fund, about her work restoring cottonwoods to the Mississippi River floodplain.

Cottonwoods are important, not least because they are large enough to be prime nesting sites for bald eagles.  Perhaps less well known, though, are the ways in which cottonwoods fix floodplain soil and, while water is high, provide important fish habitat.

But it’s that very high water that may be one of the primary reasons why cottonwoods seem not to be reproducing.  According to DeLaundreau, a 2011 National Park Service survey indicated that there may not have been reproducing cottonwood stocks for the past two decades or so.  Since cottonwoods have little direct commercial value, forestry studies have largely not explored why stands may be dying out.

To many of us city dwellers, the Mississippi River flood plain looks healthy, with robust stands of vegetation, a big river flowing south, and occasional boating traffic.  And it’s not the case that the floodplain is dying, exactly, but rather that its complexity is being reduced and the systems that make up a healthy ecosystem are being simplified.

Perhaps this is our best approach river restoration: one key piece at a time.  Aldo Leopold said that “to keep every cog and wheel is the first requirement of intelligent tinkering.”  The second requirement might then be “think of the system before trying to put any single part back in place.”

 

 

Patrick Nunnally | June 17, 2014 at 8:18 am | Categories: Planning, Science | URL: http://riverlife.umn.edu/?p=5798