Ag Policy Blog

Algae, Dead Zones, Climate Change and the Soil Health Movement

Chris Clayton
By  Chris Clayton , DTN Ag Policy Editor
Connect with Chris:
A NASA satellite image of an algae bloom in Lake Erie in 2015. Vibrant green filaments extend out from the northern shore.

A pair of separate studies and multiple corresponding articles over the past week highlight the importance of both precision agriculture and the soil-health movement without actually mentioning those efforts.

Multiple reports have cropped up pointing to on the long-term impacts of fertilizer in waterways and in the food system.

The first, from a study published in Science magazine, pointed to eutrophication, or excessive nutrient enrichment in waterways. The study states thatmore precipitation in parts of the country over time because of climate change will substantially increase nitrogen loads in waterways over the rest of the century. As the study cites, "The impacts, driven by projected increases in both total and extreme precipitation, will be especially strong for the Northeast and the Corn Belt of the United States."

Further, offsetting this problem will require roughly a 24% reduction in nitrogen inputs "representing a massive management challenge," the study authors wrote.…

Basically -- without changes in both nutrient management and climate policies -- excessive nitrogen willlead togreater hypoxia problemsin areas such as the Gulf of Mexico as well as moreharmful, toxic algae blooms. Increased precipitation would drive heavier loads of nitrates into areas such as the Mississippi River and Great Lakes basins.

“When we think about climate change, we are used to thinking about water quantity — drought, flooding, extreme rainfall and things along those lines,” Anna Michalak, a professor of global ecology at the Carnegie Institution for Science in Stanford, Calif., and one of the authors of the study, told the NYT. “Climate change is just as tightly linked to issues related to water quality, and it’s not enough for the water to just be there, it has to be sustainable.”…

This isn't the first time climate change and nutrient loads have been linked to water-quality challenges. As far back as 1989, EPA wrote in a study that water quality would be degraded as higher temperatures lead to increased algal productions combined with increased challenges with agricultural runoff.…

The challenges with algae blooms and dead zones also were spotlighted this week by the academic website, The Conversation, in a piece by Donald Scavia, a professor of environment and sustainability at the University of Michigan. Scavia compares voluntary efforts to reduce nutrient pollution around Lake Erie and Mississippi River basins with mandated actions facing states in the Chesapeake Bay. Scavia states that voluntary actions over the past 30 years in the Mississippi River basin have largely failed. Nutrient loads in the Mississippi have not declined since the 1980s. Nutrient loads in the Chesapeake, however, have reported lower nitrogen, phosphorus and sediment levels since EPA put the Chesapeake on a "pollution diet" in 2009.…

In another related article, the Des Moines Register reported Tuesday on a study conducted by an environmental group called Mighty Earth. The group linked fertilizer loading from corn and soybeans directly to meat companies, specifically pointing to Tyson, Smithfield, JBS and major grain processors such as Cargill, Bunge and Archer Daniels Midland.

As the report notes, "when excessive fertilizer and manure wash off fields that grow feed, they contaminate local drinking water and create toxic algae blooms that cause vast Dead Zones that re toxic to aquatic life in the Gulf of Mexico, Chesapeake Bay and Great Lakes."

Mighty Earth called on companies such as Tyson to demand "pollution-free feed" for their livestock. Tyson, as the Register quoted, stated it doesn't agree with Mighty Earth's "characterization of our company but share its interest in protecting the environment." Tyson added that the company is working with World Resources Institute "to develop goals for improving our environmental footprint."…

Such a push ties directly into corporate goals of major retailers such as Walmart to lower the volumes of nitrogen fertilizer used on crops that lead to foods ending up on the company's grocery shelves. Walmart wants to reduce fertilizer usage on at least 14 million acres of farm ground by 2020.…

All of this draws back to the work of groups such as the Soil Health Institute, the Soil Health Partnership, Field to Market and other efforts right now to increase attention on farming practices that reduce runoff and build organic matter and resiliency in the soils.

Then there is the somewhat quiet talk about what will happen with conservation programs in the next farm bill. What's the next step beyond the Conservation Stewardship Program to elevate best management practices on the ground? Can the farm bill jumpstart "ecosystem markets," which seem to be flailing when put into actual practice? These topics aren't getting much traction in the farm-bill debate right now that is heavily tilted toward the commodity title and crop insurance.

EPA may be on a regulatory sabbatical, but the battles over the impacts of nitrogen and phosphorus loading aren't going to go away.

Chris Clayton can be reached at

Follow him on Twitter @ChrisClaytonDTN


To comment, please Log In or Join our Community .

SD Farmer
8/8/2017 | 9:20 AM CDT
Farmers apply fertilizer to land where it is used by the crop and is filtered by the soil. We try the best we can, how about everyone else? The MNDOT used 304,000 tons of salt on there roads in 2012-2013. That is the equivalent to roughly 12,000 semi trailer loads of salt. That is applied on roads that don't absorb anything that lead directly to unfiltered and untreated storm sewer drainage that is discharged directly into rivers, a majority in the Mississippi. Along with rubber tire residue and what else. It is the same as backing the truck up to the river and dumping the salt straight in. This is just the MNDOT, not cities or other states in watersheds. I guess since a majority of people live in cities this is acceptable and they continually blame the minority of farmers for all of the pollution. That's discrimination and is hypocritical. Sounds like fake news is common in agricultural reporting as well! Get real! If only we could make sense common again, then we can make America Great Again!