Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/24/1998
Publication Date: N/A
Technical Abstract: While considerable information exists on the decomposition of foliar residue, little is known about root decomposition. Carbon (C) and nitrogen (N) transformations during root decomposition contribute to organic matter production and N availability in agricultural ecosystems. Information on root decomposition dynamics is required to evaluate the relative importance of root material to soil organic matter formation, understanding of nutrient cycling, and soil quality. Wheat roots were incubated in a silt loam soil at 25 degrees C. and sampled periodically for 55 days. Carbon and N were determined by standard laboratory techniques. Wheat root C mineralization of began very rapidly, probably due to the soluble C compounds in the roots. However the mineralization rate decreased steadily during the incubation period. Root C mineralization was substantially less than C mineralization from residue. Nitrogen was immobilized by the addition of wheat roots and decreased net mineralization when compared to unamended soil. The immobilization rate decreased during incubation.