Effects of Coal Amended Soils on Growth Rates of Native Grass Species in the Southwest. (S07-fessenden981165-poster)
Authors:
J. Fessenden* - Los Alamos National Laboratory P. Unkefer - Los Alamos National Laboratory J. Heikoop - Los Alamos National Laboratory M. Ebinger - Los Alamos National Laboratory
Abstract:
Native grass species growing in coal-amended, calcareous soils of the semiarid southwest can be unexpectedly productive. Decreased pH and increased carbon from coal mine spoils (gob) enhanced the growth of native grasses in these naturally high pH soils. Two native grasses, little blue stem and buffalo grass, were planted in various soil gob mixtures in a greenhouse. Carbon and nitrogen stable isotope ratios and concentrations in the soil/coal mixtures and the vegetation were measured to address nitrogen uptake, plant growth potentials, and water use efficiency; soil water capacity and pH were also measured in this experiment. The buffalo grass had the highest viability, largest percent carbon and nitrogen, most depleted 13C ratios and the lowest water use efficiency in the 1/3 soil and 2/3 coal amended soil. The nitrogen isotopic values from the leaves showed that the vegetation incorporated nitrogen from the gob and could be an indicator for enhanced nitrogen availability from the gob to overlying vegetation. Overall, we found that increased nitrogen and carbon availability and the
neutralizing effect of the gob can enhance vegetative growth. In the Southwest, where alkaline soils are prevalent, coal mine tailings might be a viable soil amendment and may increase growth and
sustainability of native plant species.
Speaker Information: Julianna Fessenden, Los Alamos National Laboratory, MS D-462, EES-6 Los alamos National Laboroatory, Los Alamos, NM 87545; Phone: 505-667-5468; E-mail: [email protected]
Session Information: Monday, November 3, 2003, 3:00 PM-5:00 PM Presentation Start: 3:00 PM (Poster Board Number: 1608)
Keywords: carbon isotopes; native grass growth; coal amended soil; soil reclamation