Sunday, June 21, 2009

Gulf Hypoxia

Predictions are for the Gulf of Mexico to have a large area of hypoxia (low oxygen conditions) this summer. The hypoxic zone is the second largest in the world and is believed to have several causes including nutrients coming from the Mississippi River and loss of wetland habitat near the Gulf. These are interconnected.

At one time Mississippi River water flowed through wetlands providing nutrients for them. With the advent of navigation the river was straightened and bypassed wetlands providing easier ship movement, but loss of nutrients to the wetlands and the dumping of those nutrients into the Gulf contributing to the zone of hypoxia. 1 million acres of land/wetland have been lost in the Gulf area in the last 150 years. Another acres is lost every 38 minutes.

Two things need to happen. Delivery of nutrients should decrease and replumbing through wetlands should happen. Nutrient delivery varies greatly. This year delivery was 23% lower than last year, but still 11% above the 1979-2009 average.

Hypoxia can be hard to predict as it depends on many things - flow from the Mississippi River, nutrients in that flow and storms that mix the waters of the Gulf (diluting the River flows). This year's hypoxic zone is expected to be on the larger size.

We in Iowa have an opportunity to affect the amount of nutrients delivered. One of the ways we do that is using wetlands in Iowa to manage the nutrients through our CREP program. You can find out more about that at I will write more about this later. We hope to expand this program for it can reduce the amount of N in water in Iowa and the Gulf and create wetland habitat in Iowa.

So much to do, so little time!