Green Daily

Didn't you hate it when your mother would pull you aside after bandaging your knee and say, "You know, Molly, all of this could have been avoided if you'd have just watched where you were walking." Yeah, mom. Thanks. Thanks a lot college roommate Sara for telling me I could have avoided frying my laptop had I not set my coffee next to it in the first place.

Thanks, thanks, and thanks again for pointing out that I'm a human. Idiot. Perhaps, a human idiot.

Well, here's another example where perhaps we humans could have watched where we were setting our coffee cups and knees. Or, in this case, where we built our cities and cut down our trees.

All this water in Iowa has me thinking about a story I wrote for Minnesota Public Radio on one state park's recovery from a flood. In it, the park naturalist points out that in southeastern Minnesota floodplain forest can absorb as much as nine inches of rainfall an hour. Plant roots help absorb water and anchor the soil in place, avoiding run-off.

Other research and organizational Web sites have indicated forests can absorb four to six inches of rain an hour. This is all dependent on the type of land and forest conditions. But most of what fell in Minnesota last year, and in Iowa this year, fell on cropland. And cropland is designed to drain quickly and directly into rivers and streams. Cities are also known more for their pavement than their absorbent forests and prairies.

Cutting down forest land in favor of agricultural land may produce more food, but it also produces more water. Oddly enough, it also produces less. An article on rain forests by Woods Hole Research Center discusses another shortcoming of deforestation: when the canopy is chopped away humidity is decreased making fires more likely and storing water in deep root systems more difficult.