The government is looking at programs to reduce the amount of fertilizer runoff from farms that ends up in streams and rivers. It’s necessary because 41 percent of the continental U.S. drains into the Mississippi River and all that runoff is dumped into the Gulf of Mexico. There, it’s causing a ‘dead zone’ where fish and other aquatic life can’t live. The Great Lakes Radio Consortium’s Lester Graham reports:
The government is looking at programs to reduce the amount of fertilizer runoff from farms that
ends up in streams and rivers. It’s necessary because 41-percent of the continental U.S. drains
into the Mississippi River and all that runoff is dumped into the Gulf of Mexico. There it’s
causing a ‘dead zone’ where fish and other aquatic life can’t live. The Great Lakes Radio
Consortium’s Lester Graham reports:
Each year about one-and-a-half million metric tons of nitrogen is dumped into the Gulf of
Mexico. Plants feed on nitrogen, so there are huge algae blooms, far more than the tiny aquatic
animals that feed on algae can eat. The algae eventually dies and begins to decompose. That process
depletes oxygen from the water. Fish and other marine life need oxygen to live. So they leave
the oxygen-depleted area or die. It’s called a ‘dead zone.’ In recent years that ‘dead zone’ in the
Gulf of Mexico has been as large as the state of New Jersey.
Don Scavia is Chief Scientist with the National Oceanic and Atmospheric Administration’s
National Ocean Service. He says it looks as though much of that nitrogen comes from farms in
the Mississippi basin.
“The most significant change in the nitrogen load into the basin is actually coming from
agricultural application of fertilizer. That application rate has more than tripled since the 1950’s,
corresponding to almost a tripling of nitrogen loss from that system into the Gulf.”
Farms that are hundreds of miles from the Mississippi River drain into the Mississippi River
basin. The basin stretches from Montana to the southwest tip of New York. It includes all or
parts of 31 states.
Nitrogen exists naturally in the environment. But growing corn and some other crops on the
same land year after year depletes nitrogen. So farmers fertilize the land to bolster nitrogen
levels. Sometimes they use animal manure, but often they use man-made fertilizers such as
David Salmonsen is with the American Farm Bureau.
“Well, for several crops, especially out into the upper parts of the Mississippi River basin, the
Illinois, Indiana, Iowa, southern Minnesota, the great Corn Belt, you need nitrogen as a basic
additive and basic element to grow, to grow these crops.”
But often farmers use more nitrogen than they really need to use. It’s called an “insurance”
application. Farmers gamble that using an extra 10 to 20 pounds of nitrogen fertilizer per acre
will pay off in better crop yields – more corn. A lot of times, that gamble doesn’t pay off because
rain washes the extra nitrogen off the field. Salmonsen says slowly farmers are moving toward
more precise nitrogen application.
“Try and get away from what, you know, for years has been a practice among some people, they
say ‘Well, we’ll do what they call insurance fertilization. We got to have the crop. It may be a
little more than what we need, but we’ll know we have enough,’ because they just didn’t have the
management tools there to get this so precisely refined down to have just the right amount of
Salmonsen says with global satellite positioning tools, computers, and better monitoring farmers
will soon just be using the nitrogen they need. But, it’s not clear that farmers will give up the
insurance applications of nitrogen even with better measurements.
The government is getting involved in the nitrogen-loading problem. A task force has been
meeting to determine ways to reduce the amount of nitrogen that reaches the Gulf of Mexico.
Among the strategies being considered are applying nitrogen fertilizer at lower rates, getting
farmers to switch from row crops to perennial crops so they don’t have to fertilize every year,
planting cover crops during fall and winter to absorb nitrogen, establishing artificial wetlands in drainage areas to absorb nitrogen and getting
farmers to plant buffer strips of grass between farm fields and nearby waterways to filter out nitrogen.
Tom Christiansen is with the U.S. Department of Agriculture. He says while the government task
force is considering recommending some specific basin-wide reductions in nitrogen use the
USDA is only looking at the problem farm-by-farm.
“We get good conservation on the land, good water quality in the local streams and that will
benefit the Gulf. So, we’re working on a site-specific basis. We haven’t established any kind of
nation-wide goal for nutrient reduction.”
Unlike other industries, the government is reluctant to mandate pollution reduction. Instead of
regulations and fines used to enforce pollutions restrictions with manufacturing, agriculture is
most often encouraged to volunteer to clean up and offered financial incentives to do that. But in
the past farmers have complained that there wasn’t enough money in the programs. Christiansen
says the new farm bill has more money for conservation efforts and that should make it more
appealing for farmers to reduce nitrogen pollution.
“It falls back to good conservation planning, using the correct programs and then providing the
right kind of incentives and benefits to producers because they are taking land out of production
in many cases.”
The government is assuming the voluntary programs will be enough to reduce the nitrogen flow
into the Gulf of Mexico. No one expects the ‘dead zone’ will be eliminated. The best that
they’re hoping for is that it will be significantly reduced.
For the Great Lakes Radio Consortium, this is Lester Graham.