Nutrient Reduction Strategy Working, Slowly
DES MOINES, Iowa — The Iowa Nutrient Reduction Strategy (IRNS) was passed in 2013 to help stop nitrogen and phosphorus from getting into the water. Every year, it has an annual report for the governor to see if there has been progress.
Last year, there was a small amount of progress. Nutrient reduction was about 1.5 percent for nitrogen and 2.2 percent for phosphorus.
The biggest change for conservation practices right now is cover crops. In 2011, there were fewer than 40,000 acres, now there’s nearly 400,000.
According to the report, among what practices can be calculated, cover crops block the vast majority of nutrients from leaving land. Two-thirds of nitrogen, about 2.4 million pounds, stopped by cover crops as well as 90 percent of phosphorus, about 196,000 pounds.
CREP Wetlands stopped most of the other third, about 1.4 million pounds of nitrogen.
Voluntary nutrient reduction like these takes time. At this rate it will take years to get to the goal of 45 percent.
Dr. John Lawrence, an Associate Dean at Iowa State University, says looking back at agriculture, practices seem like they were adopted quickly, “But you think of adoption of hybrid seed corn, if you think of the movement from horses to tractors, if you think of even things like GMO’s, and glyphosate resistant crops. Those things took, in many cases to get to high levels of adoption, [a] decade or decades.”
It has four indicators in it’s logic model approach: First it monitors the water; then it calculates a nutrient load reduction by monitoring changes to the land; it also surveys farmers to see human behavior changes; finally it checks out inputs, like education, information, cost shares, and by monitoring spending.
2016 saw an increase of nearly $10 million in IRNS funding, up to nearly $122.7 million.
But conservation still has its challenges according to Lawrence, “Those practices that keep soil in place, don’t always keep nitrogen in place, in fact often times they’re not doing things to reduce loss of nitrates to our water supply. What the Nutrient Reduction Strategy does is look at both of those. What practices will address the loss of both nitrogen and phosphorus from our landscape.”