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Biological Remediation Of Fragipan, Corey Hale

Honors College Theses

The fragipan layer in the soil is a naturally occurring subsurface layer that restricts water percolation as well as inhibits root growth. A fragipan layer can be found almost ubiquitously across Southwestern Kentucky. This limits how agriculturalists manage soils in this area. It has been recently discovered by the University of Kentucky that Annual Ryegrass roots produce 3,4 dihydroxyphenylpropionic acid (DHPPA) that reacts with this hardpan to weaken the layer. Certain bacteria, such as Escherichia coli, Lactobacilli, and Bifidobacteria can also synthesize DHPPA through a breakdown process of chlorogenic acid. This reaction typically happens in the human digestive tract. …