|
Surplus phosphorus is a common problem for Midwest farmers. When too much phosphorus gets into water, largely from manure applications or over fertilization of land, it can increase aquatic plant growth, creating “pond scum” that cuts off sunlight to the water creatures below. Norton tested the use of recycled gypsum as a way to reduce phosphorus run-off and found that it was a low-cost way to significantly reduce phosphorus movement.
This past summer, Norton and a team of researchers further tested the ability of gypsum to reduce agricultural run-off in the St. Joseph River watershed, which supplies drinking water to the Fort Wayne area. For three weeks, the research team simulated rainfall on soils where manure was applied with gypsum. Soil and water run-off were measured to see how well gypsum affected the ground’s ability to retain phosphorus and farm chemicals, such as atrazine. Preliminary results indicate that the gypsum additive worked well, with final data to be available sometime next year.
Partly based on some of Norton’s earlier work, crop consultant Ron Chamberlain created a business of recycling wallboard salvaged from new home construction and made up of gypsum, for processing and farmland application. Chamberlain, a 1971 Purdue engineering graduate, says it’s a plus-plus situation. “I’m intercepting waste from the landfill and putting it to beneficial use,” he says.
 |
This machine simulates rainfall so that researchers can measure soil and water run-off on a test plot where manure was applied with gypsum. |
New working model
In the case of Schwab and Graveel’s experiment to grow grass in slag, the results were mixed. Growing conditions this past summer weren’t always favorable, as rainfall was limited and temperatures soared. The planting of the plots was also hampered by some inconsistencies. However, most of the sites were “not too horrible,” and some of the slag sites proved very productive. “It was surprising, but at one site with huge rocks the grass grew quite well,” Schwab says.
While industry and agriculture may not seem compatible, both are finding benefits in working together to improve the environment. The significance of experiments like these is the opportunity to take a product that has no apparent use and make it beneficial. “We can be creative and find solutions that allow industry to move forward and yet minimize the impact it has on the land,” Schwab says.
|
