In Lake Erie, eliminating problematic algae starts with reducing the amount of food you feed.
Written by Joshua A. Bickel and Patrick Attula-Orsagos
On a warm late summer night, a small speedboat cruised along the pea greens of Lake Erie, past beaches where children sat splashing in the water and newlyweds strolled for portrait photographers. Bright red signs were posted on the beach warning people not to enter the water due to invisible and ignored dangerous algae toxins.
About 110 miles away, farmer Bill Kellogg is trying to do something about chronic algae blooms in America’s southernmost Great Lakes. Instead of spreading fertilizer over the fields, Kellogg now uses a strip tiller to cut fertilizer pellets into the soil up to 8 inches (deep enough to prevent them from being washed away by heavy rains).
He plants cover crops to strengthen the soil so it can absorb more nutrients. In other areas, some crops have been replaced with buffer zones of grasses and other plants. Nutrient runoff can be absorbed before it flows into the river heading toward Erie, where it becomes a powerful fuel for algae.
“We recognize that there is a target in the agricultural industry,” Kellogg said.
Bacteria, commonly called blue-green algae, are common in waters around the world, but ingesting too much phosphorus and nitrogen from farm fertilizers can lead to harmful algae blooms that can affect drinking water or cause oxygen depletion. May cause death. Zones that kill marine life, ruin swimming, boating and tourism, and endanger human health.
West Lake Erie is an ideal environment for bacteria to grow. The lake is about 30 feet deep, making it the shallowest part of the Great Lakes and heats up quickly when temperatures are warm. And that’s where nutrients from fields along streams and creeks throughout the watershed ultimately flow into the Maumee River and into Erie, Toledo.
Nutrient runoff from agricultural land, mostly fertilizer, makes up about 80 percent of the nutrients entering Lake Erie, and half of the nutrients that reach the lake arrive via the Maumee River.
Reducing the amount of nutrients, particularly phosphorus, was one of the focuses of a 2015 agreement between the United States and Canada to reduce phosphorus entering Erie by 40% by 2025. Researchers say progress has been made, with the latest figures showing a reduction in phosphorus. Approximately 32%, but the goal may not be achieved.
Algae blooms in western Lake Erie this year were modest compared to previous years. It appeared on June 24, the earliest day since observations began, and at its peak in late summer covered about 660 square miles. This one was larger than usual, but not as thick as the other flowers.
Rising temperatures are expected to cause algae to bloom earlier and last longer, and potentially become more toxic as more intense storms wash nutrients into waterways and warmer lakes warm up. .
“If all things remain the same and the climate changes as we expect in the coming decades, the situation will get much worse,” said Nate Manning, interim director of the National Center for Water Quality. Ta.
Farm conservation has long been a personal priority for Kellogg, who farms 7,400 acres of corn and soybeans in Forest, Ohio. He and his family regularly visit Lake Erie and enjoy fishing and swimming. But he became even more enthusiastic after the 2014 bloom temporarily cut off drinking water to more than 400,000 people in Toledo and southern Michigan.
“Once that happened, we really hit the ground running,” Kellogg said.
Mr. Kellogg spent more than $1 million on a strip tiller and a tractor to pull it, which can push solid fertilizer several inches below the surface. Although it was a large expense, the company says it has reduced fertilizer runoff and reduced fertilizer spending by about $300,000. The liquid fertilizer he sometimes uses is stored in a tank placed in a concrete tub to prevent leaks.
“Yields have gone up. Fertilizer costs have gone down. Once we get hooked on something and prove to ourselves that it works, now no one has to pay us,” Kellogg said. he said.
Near Sandusky Bay in the southwest part of Lake Erie, the Ohio Department of Natural Resources is working with other conservation groups to restore wetlands that filter nutrient runoff entering the bay. At one site, engineers reconnected a waterway through an area of āāformer agricultural land, returning the area to wetland status. In another example, island barriers are being built near shorelines in addition to wetland restoration to aid filtration.
As part of the H2Ohio program, which began in 2019, the Ohio Department of Natural Resources and its conservation partners have completed 23 wetland restoration projects in the western Lake Erie Basin, with 49 more underway. These are helpful, but only part of the solution, said Mary Martz, director of the Ohio Department of Natural Resources.
“Creating wetlands alone won’t make Lake Erie cleaner,” she says. āOther things have to happen.ā
Researchers at the National Water Research Center in Tiffin constantly monitor phosphorous in the water. Their data shows that although phosphorus loading to western Lake Erie is trending downward, the 40% reduction goal has not been consistently met.
“There’s a lot to be positive about,” Manning said.
But more funding is needed and more farmers need to adopt conservation and nutrient management practices, said Emily Kelley, agriculture and water coordinator for the Ohio Environmental Council. To meet these reduction goals, Ohio would need to increase spending by $170 million to $250 million, according to a 2023 report from the group and the Great Lakes Alliance. Michigan would need to spend between $40 million and $65 million.
According to 2023 data, Ohio farmers have approximately 1.5 million acres in the western Lake Erie watershed enrolled in nutrient management plans with the state. This represents about 43% of the watershed’s agricultural land, and the goal is to have at least half registered, Carissa said. Mr. Cochran is a spokesperson for the Ohio Department of Agriculture.
Farmers develop their own plans and are eligible for incentives of up to $40 per acre, but are not required to meet nutrient load reduction goals. They work with local soil and water conservation districts to select the most effective methods for their fields, including cover crops and targeted fertilizer placement.
For some farmers, getting results may require multiple tasks, including buffer strips and expensive machinery like Kellogg’s. All of this can be discouraging to some people, said Jordan Heuscher, director of water quality and research for the Ohio Farm Bureau.
Kellogg believes that if more farmers voluntarily adopt such conservation practices, the government will be less likely to intervene with regulations. He wants farmers to do it themselves.
“We were probably part of this problem from the beginning,” Kellogg said. āItās up to us to be part of the solution.ā
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Source: In Lake Erie, eliminating problem algae starts with reducing food (October 22, 2024) from https://phys.org/news/2024-10-lake-erie-problem-algae- Retrieved October 22, 2024 food.html
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