COS 1-1 - Using mixed litter to enhance nitrogen fixation during decomposition

Monday, August 7, 2017: 1:30 PM
E143-144, Oregon Convention Center
Noa Lincoln, TPSS, University of Hawaii, Honolulu, HI

Nitrogen plays an essential role in sustaining agricultural yields. While nitrogen fixation has been recognized as a key process for sustaining nitrogen through ecological processes, emphasis has been on symbiotic nitrogen fixation in growing plants. However, asymbiotic nitrogen fixation can be a significant contributor to the nitrogen balance. We have been conducting mulitple decomposition studies using single and mixed litter samples to assess nitrogen fixation in an effort to enhance nitrogen fixation rates for the benefit of low-input agriculture and the application of agroecological techniques.


We have found that nitrogen fixation in sugarcane (Saccharum officinarum) litter decomposition is a substantial contribution to agricultural systems, but varies by an order of magnitude depending on specifics of the practices. When mixing sugaarcane litter with other species we primarily see a reduciton in nitrogen fixation rates, however specific combinations show slight inceases, suggesting that an opportunity exists to refine mulching techniques and increase nitrogen inputs to farming systems.