Dissertation Research: Plant Organic Nitrogen uptake in Temperate Terrestrial Ecosystems

University Of Georgia Research Foundation Inc, Athens GA

Investigators

Abstract

This research addresses the roles of direct organic nitrogen (N) uptake in higher plant nutrition and terrestrial ecosystem nutrient cycling. It is hypothesized that plant use of organic N, particularly free amino acids (AA), is more prevalent in terrestrial ecosystems than currently perceived. Although the extent of AA uptake may depend on a variety of soil and plant factors, AA uptake may act as a general mechanism of plant N acquisition along with mineral N uptake. The research will use stable isotope labeling techniques in field and greenhouse experiments to investigate the generality of AA uptake, and to quantify the contribution of directly acquired external AA to plant productivity and nitrogen cycling for four contrasting ecosystems in the Southeast USA. This research will investigate AA uptake by plants growing in situ in temperate terrestrial ecosystems, and the ecological implications of AA uptake in these ecosystems.