The state is at a fork in the road when it comes to agriculture and water quality, says Sean McMahon, executive director of the Iowa Agriculture Water Alliance.
Speaking at the recent Iowa Soybean Research Conference in Ames, McMahon said growing pressure exists to make progress on water quality. Many people are calling for regulation of the ag sector not just in Iowa but in the Mississippi River Basin, the Lake Erie Basin and the Chesapeake Bay Watershed.
“This is going to be an inflection point that determines which path we go down,” McMahon said. “On the one path we have regulation, potential litigation and a lack of incentives to implement conservation practices. On the other path, we maintain voluntary conservation incentives and funding to do so, maintain our flexibility in deciding which practices will work best on our own fields and are incentivized to implement those practices.”
The best way to stave off regulation is to show progress at the watershed scale, McMahon said. That can be accomplished by targeting conservation practices identified in the Iowa Nutrient Reduction Strategy and the Water Quality Initiative, having water quality monitoring that demonstrates progress as well as other measures.
The alliance is an initiative supported by Iowa Corn Growers, Iowa Soybean Association and Pork Producers to encourage farmers to adopt voluntary practices designed to reduce nitrogen and phosphorus in waterways. The practices are cover crops, nutrient management, conservation tillage, nutrient treatment wetlands, bioreactors, saturated buffers, drainage water management, buffers, grass waterways, terraces and prairie strips.
“I encourage all the producers in this room to think long and hard about what the Iowa Nutrient Reduction Strategy means to you and what part you can do to help implement the strategy and help all of Iowa agriculture head down what we all agree will be the right path of cooperation, collaboration and voluntary conservation incentives that are scientifically proven to improve water quality,” McMahon said.
Continual water quality improvement
Chris Jones, environmental scientist with ISA’s Environmental Services Program, echoed McMahon’s admonition. The focus must be on making continual improvement.
“We need to make a quantum leap to improve the condition of streams in Iowa,” Jones said.
ISA and the alliance have monitored thousands of samples from the Raccoon River for nitrate since 1999, Jones said. The monitoring showed concentrations declined at 39 of 41 sites with eight declines statistically significant. A decline of 0.26 milligrams nitrate per liter per year overall occurred in the Raccoon River Watershed.
“But we have to be very cautions in talking about trends,” Jones said. “If you get too bold, bad things happen.”
Looking at the entire record of nitrates in the Raccoon River dating back 40 years, it doesn’t appear that there is a decreasing trend, Jones said. Splitting 40 years into two 20-year periods, the most recent 20 years look worse. Looking back to the early 1970s, nitrate loading may have been worse in the early 1980s, then improved, then got worse and then improved in recent years.
“The problem with making claims of trends for a contaminant where annual variations are driven by weather is that we can go backwards,” Jones said. “If we’re expanding and enhancing the primary delivery mechanism, which is drainage, there is no reason to think positive trends will continue. When we look at recent years, we see some evidence that maybe things are changing for the worse. We don’t know, but it’s possible.”
Agriculture needs to transform in ways that dramatically affect the delivery of nitrogen, he said.
“It’s hard to make changes to an operation,” Jones said. “We know that. Anxiety about what might happen can result in people doing nothing at all.
“We have to get beyond the anxiety to make necessary changes such as the widespread adoption of cover crops,” Jones said. “We need to understand all details of the system that enable us to make the changes. There is so much talk about the system but so little understanding of the details.”
Design drainage systems
If Iowans were to go about designing a drainage system today, it would look different.
“We’d at least do it in a way to design in mechanisms to mitigate the consequences we’re battling with now,” Jones said. “Our mission now is to figure out how to make the system work in ways that people downstream will appreciate.”
The majority of Iowa’s Des Moines Lobe, which encompasses much of north central and central Iowa, is artificially drained with tile drainage systems installed in the mid-1900s, said Matt Helmers, Iowa State University agriculture and biosystems engineering professor. Many of these systems are under designed based on modern standards and current cropping systems.
“Over the next decades, drainage systems in Iowa’s drainage districts will be replaced,” Helmers said. “There may be opportunities to integrate some of the conservation practices laid out in the Iowa Nutrient Reduction Strategy to optimize the system for both environmental benefits and crop production.”
Jim Gulliford, executive director of the Soil and Water Conservation Society, said that 150 years of cultivation have taken a toll on soil and water resources.
“To meet future demands for food, fiber, fuel and forage, we have to do more than protect our soil resources,” Gulliford said. “We need to restore Iowa’s soils, which are our most important crop production asset.”
Adding cover crops to a conservation system can to restore soils, Gulliford said.
Read the story in its entirety at AgriNews.com.