Five LSU AgCenter research teams have received grants totaling more than $1.7 million to study how forest and agricultural best management practices (BMPs) affect water quality in Louisiana.
Scheduled to be completed over the next three years, the projects are funded by the U.S. Environmental Protection Agency through the Louisiana Department of Environmental Quality. They are aimed at studying the effectiveness of the management practices, which are designed to help agricultural producers reduce pollution and increase their productivity and profit.
As part of the research, two teams are evaluating agricultural areas in individual watersheds — where all the water that runs off the land ends up in a single body of water.
A third team is evaluating water quality in the upper Bayou Nezpique and Beaver Creek drainage area in Evangeline Parish, while another project involves developing an Internet Website and CD-ROM to help forest owners and loggers apply best management practices to improve water quality in Louisiana.
The final team is studying how different operating methods can influence the quality of water in crawfish ponds.
In the first two studies, researchers are evaluating water quality in the Cole Gully area on the Bayou Plaquemine-Brule in Acadia Parish and in Bayou Wikoff north of Lafayette. Each study area is a watershed identified and selected by the Louisiana Department of Environmental Quality. The research teams are monitoring water runoff from agricultural fields, as well as from other sources, to measure pollutant levels and compare them with how the land is being used.
“We'll look at different best management practices and determine which are most effective and least burdensome,” said Lewis Gaston of the LSU AgCenter's Department of Agronomy. “It's an implementation demonstration project.”
Gaston explained that cooperating farmers will “implement management practices that will positively impact water quality.” Then the researchers will intercept water coming off particular fields and measure the amounts of sediment, nutrients and other pollutants in the water.
Magdi Selim, also of the LSU AgCenter's Department of Agronomy, said the researchers want to quantify “how to manage sediment losses and agricultural chemical losses reaching water bodies.”
The researchers are installing sampling stations between the edges of each field and the bayous.
“We want to look at the edge of the field and see what comes out,” Selim said, explaining researchers expect to see reductions in sediments and nutrients, as well as dissolved carbon, in fields where BMPs have been implemented.
Another LSU AgCenter research team is monitoring water quality and populations of invertebrates and fish at locations where timber is being harvested in the upper Bayou Nezpique and Beaver Creek drainage area.
“We'll be measuring water quality above and below the sites to determine if they're contributing to reduced water quality,” said Allen Rutherford of the LSU AgCenter's School of Forestry, Wildlife and Fisheries.
Rutherford and fellow researcher Bill Kelso said they're evaluating the effectiveness of forestry BMPs, which are management methods recommended by the Louisiana Forestry Association and the Louisiana Department of Agriculture and Forestry. Those practices include providing good drainage in the construction of roads and log skid trails, leaving streamside management zones along rivers and streams and keeping heavy equipment out of streams.
The researchers said they're particularly interested in streamside management zones — the area between the water's edge and the harvest area — and contour road building.
“We need to look at all land use activities,” Rutherford said.
Because forestry represents a nearly $3.3 billion industry in Louisiana, “The forest industry is out in front and wants BMP programs to be successful,” Kelso said, adding, “Timber companies do a good job of protecting water quality.”
In a related project, Mike Dunn, a forest resource economist with the LSU AgCenter's School of Forestry, Wildlife, and Fisheries, is producing interactive computer materials Louisiana's forest industry can use to improve and maintain water quality affected by timber harvesting.
“The development and implementation of forestry BMPs have been around in Louisiana much longer than any other commodity or crop,” Dunn said. “Louisiana has been working with and developing BMPs as long or longer than anybody in the United States.”
Based on the Louisiana BMP Guide for Forestry, Dunn is accumulating information, putting it on CD-ROMs and on the Internet, and making it interactive.
“For example, we can provide decision-making tools so loggers can enter information specific to the site on which they're working and obtain a specific set of BMPs to be applied to that site,” Dunn explained.
In yet another project, LSU AgCenter researchers are monitoring water discharges from crawfish ponds, as well as water in the streams, bayous or canals, to compare the pond water with normal surface water.
Robert Romaire of the LSU AgCenter's Aquaculture Research Station said the project will sample three crawfish ponds on the Bayou Plaquemine-Brule watershed in Acadia and St. Landry parishes. Additional ponds may be sampled in the Vermilion-Teche River Basin in St. Martin Parish, as well.
“We have to do a census of crawfish to find out how many acres are farmed and water use practices,” Romaire said. “We'll develop a map of ponds, where they drain and how often they drain, and estimate the amount of water they use.”
During the succeeding years, Romaire said researchers will implement different sets of BMPs to evaluate the effect on water discharged from the ponds.
“Ponds are managed to mimic nature,” Romaire said, explaining how crawfish farmers empty the ponds in the spring to force the crawfish into burrows to lay eggs, Then, after a summer of growing vegetation that will be food for the crawfish, farmers fill the ponds to bring the crawfish out of their burrows in the fall.
LSU AgCenter researchers will use the results of these studies to evaluate current BMPs and recommend modifications if necessary.
Rick Bogren writes for the LSU AgCenter.