After being back in Jackson almost a month, I decided it was time to write a little bit about what I got out of my week-long journalism seminar in Narragansett, R.I. Called the Metcalf Institute for Marine and Environmental Reporting, the workshop immersed 11 journalisms (including me) into the world of science. We learned how data was collected… for instance… we rode a boat and pulled up a net of fish to count how many species and calculate other data. Pretty cool.
The seminar fueled one big interest of mine: the effects of nutrients in water. I have written two stories about dead zones (most recent in italics below). My next plan is to write about how natural landscaping can eliminate some of the nutrients that go into watersheds.
One big note: nutrients aren’t necessarily bad, but in excess, they can lead to a removal of oxygen in the water. The nutrients fertilize algae growth. The algae eventually dies, sinking to the bottom. As it decays, it takes oxygen out of the water. If the water has enough dying algae, all of the oxygen can be removed from the water, killing aquatic life.
A Rankin County park recently planted a “rain garden,” which is designed to hold runoff from the parking lot, which is a source of nutrients and other pollutants. The plants can break down these elements before they are eventually flushed into the Ross Barnett Reservoir nearby. When I get my house, I’m definitely planning one of these. A U.S. Dept. of Agriculture spokeswoman told me that a subdivision down in Gulfport is requiring each home to have its own rain garden. Not a bad idea for coastal communities.
Dead zones imperil
fisheries
•Large pocket of water lacking oxygen near barrier islands
By Justin Fritscher
jfritscher@jackson.gannett.com
Pockets of dead water off Mississippi’s coast are strangling marine life – and growing.
Dead zones lack oxygen and are caused by nutrient deposits into the Gulf of Mexico by rivers and streams, namely the Mississippi River. They typically appear each summer.
Mississippi’s biggest dead zone – often called hypoxia – is near the state’s barrier islands. Last July, it grew to nearly the size of Hancock and Harrison counties combined, researchers say.
University of Southern Mississippi marine science associate professor Stephan Howden said that already this year he has heard reports of dead crabs pulled from traps near Waveland. Researchers from USM’s marine science department have been studying hypoxia in St. Louis Bay and in the neighborhood of the barrier islands for years.
Department Chairman Steven Lohrenz said continued research is a must. “We saw an extensive region of hypoxia around the barrier islands, even extending further south,” Lohrenz said.
Howden said the state’s main area of hypoxia covered about 906 square miles last year. Other traditional places of hypoxia include Biloxi’s Back Bay and St. Louis Bay.
The National Oceanic and Atmospheric Administration is funding USM’s study of the algal bloom near the barrier islands.
USM plans to visit four of its stations Thursday in the Mississippi Sound, Howden said.
The nation’s largest dead zone is caused by nutrient-filled waters discharged from the mouth of the Mississippi. It averages about 7,000 square miles and hovers off Louisiana’s coast, even reaching into Texas’ coastal waters.
Scientists have been studying Louisiana’s dead zone since the 1970s and mapping it since the mid-1980s. And what they’ve noticed: It’s getting bigger.
Key researchers R. Eugene Turner and Nancy Rabalais, both of Louisiana, predicted this year’s dead zone will be 8,456-9,668 square miles. The forecast released last week was based on nutrient levels in the Mississippi and Atchafalaya rivers.
The Louisiana researchers will measure it at the end of the summer, when it will likely be at its peak.
In Louisiana, hypoxia has impaired some of the state’s fisheries. And it could very well affect Mississippi fisheries, too, Rabalais said.
Fishing is a crucial industry in the Gulf. Pascagoula is the Gulf’s third-largest port for poundage shipped out, 178 million pounds a year.
Rabalais said data collected earlier this month suggest dead zones are forming east of the Mississippi River and could be severe. Although the Mississippi’s flow tends to be western, during the summers it has a lower tendency to flow westward, Lohrenz said.
This means more of the nutrient-filled water – stocked with fertilizer runoff from farms upstream – is making its way into Mississippi’s coastal waters.
Nutrients such as phosphorous and nitrogen are the principal culprits, Natural Resources Conservation Service district conservationist Murray Fulton said.
Nutrients don’t have toxins, but they do stimulate phytoplankton growth. The phytoplankton dies and uses oxygen as it decays. In dead zones, all of the oxygen is depleted, killing or scattering marine life.
Rainstorms and other events cause fertilizers and other nutrients to flow down the Mississippi. At the Gulf, they act as a catalyst for phytoplankton growth.
Rivers like the Pearl or the Pascagoula have their share of nutrients, too. Fulton said his agency works with Rankin County’s 52 poultry farms to reduce the chances of large amounts of nutrients finding their way into a watershed.
Rankin County is one of the state’s biggest poultry producers. The other are Scott, Neshoba, Simpson, Smith, Clark and Leake counties. Other big agriculture in the state is corn and soybean farmers in north Mississippi, he said.
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To comment on this story, call Justin Fritscher at (601) 961-7266.
DEAD ZONES IN MISSISSIPPI
• How are dead zones formed?
Phytoplankton, a type of algae that feeds on fertilizers, settles at the bottom of the Gulf of Mexico after it dies and decays there. The decomposition of the algae consumes oxygen faster than the water can replace it at the surface, decreasing dissolved oxygen.
Harmful algal blooms can grow and alter the food web, which is harmful to local fisheries.
If no hurricane or tropical activity stirs the waters, the dead zone will remain. Storms can aerate the oxygen-depleted zone and shrink the dead zone. Dead zones peak in mid-summer and recess or disappear during the winter.
•Where do nutrients come from?
Nutrients are often fertilizers that get washed off topsoil and into the water. Common ones include nitrogen and phosphorous.
•What is the source of nutrients on Mississippi’s coast?
Nutrients end up in the Gulf from a variety of locations, the biggest being the Mississippi River. Other rivers, like the Pearl, Pascagoula, Tombigbee and Alabama also make the list. Studies show a history of dead zones along St. Louis and Back bays as well as one south of Pascagoula.
•Are dead zones just along the Gulf Coast?
No, they are all over the world. Other places in the U.S. include Chesapeake Bay and Rhode Island’s Narragansett Bay.
On the Web
•For information about Louisiana’s dead zone, visit www.gulfhypoxia.net.
•For information about University of Southern Mississippi’s marine science department, visit www.marine.usm.edu.