"Nature is going to see something it's never seen before. There is no ecosystem that has such an exaggerated change in flooding levels, even the Amazon River in South America. This annual variation in water levels will be unlike any other natural river system in the world. If done properly, ecological engineering can minimize some of the impact," said Mitsch, also director of the Wilma H. Schiermeier Olentangy River Wetland Research Park at Ohio State.
"We're saying everyone has to think outside the box."
Mitsch described these opportunities as the lead author of a letter to the journal Science published Friday (10/24).
The letter, coauthored by colleagues at Ohio State and in China, responds to an Aug. 1 Science article exploring the dam's potential environmental effects, especially on aquatic life in and around the Yangtze River.
Mitsch said farmers planting crops in the reservoir region will need to adjust, or ideally eliminate, the use of fertilizers during growing periods. Fertilizers would leave behind undesired nutrients that would promote the development of algae once standing water covers the crop fields.
"Fertilizers actually won't be needed," Mitsch said, because the sediment left behind by flooding will be rich in certain nutrients, especially phosphorus, which is beneficial to many kinds of crops.
Land users also could consider constructing cascading terraced ponds and wetlands along the border of the reservoir to retain water as it recedes and to reduce the loss of nutrients to the pulsing river system.
Perhaps the most commercially viable option would be expansive fish net systems that could be placed to capture fish at the end of the flooding season, as water levels diminish.
Though the original article explored the dam's possible harm to fish and mammals, Mitsch's letter noted that mud
|Contact: William Mitsch|
Ohio State University