| Uncertainty remains about the relationship between plant or soil nutrient status and nutrient resorption, and this relationship may be influenced by human impacts on nutrient cycling and shifts in limitation in natural ecosystems. This research examines how experimentally increasing nutrient availability affects foliar chemistry and physical characteristics. In each of five treatments (+N, +P, +NP, +Ca, control) across eight forest stands in the White Mountains of New Hampshire, nutrient concentrations of green and senesced leaves of three dominant tree species were analyzed and resorption efficiency was calculated. Calcium silicate addition affected leaf physical characteristics, but resulted in few effects on foliar chemistry. Adding N increased green and senesced leaf concentrations and resorption efficiency of N, but had little effect on P dynamics. Adding P affected foliar P, but not N, dynamics. These results raise new questions about the influence on resorption of age class, successional stage, and degree of limitation. |
