Resorption efficiency of leaf nutrients in woody plants on Mt. Dongling of Beijing, North China

Abstract

Aims To explore resorption efficiency of nitrogen (NRE) and phosphorus (PRE) of woody plants in relation to soil nutrient availability, climate and evolutionary history, in North China. Methods We measured concentrations of nitrogen ([N]) and phosphorus ([P]) in both full expanded mature green and senescent leaves of the same individuals for 88 woody species from 10 sites of Mt. Dongling, Beijing, China. We built a phylogenetic tree for all these species and compared NRE and PRE among life forms (trees, shrubs and woody lianas) and between functional groups (N-fixers and non-N-fixers). We then explored patterns of NRE and PRE along gradients of mean annual temperature (MAT), soil inorganic N and available P, and phylogeny using a general linear model. Important Findings Mass-based NRE (NREm) and PRE (PREm) averaged 57.4 and 61.4%, respectively, with no significant difference among life forms or functional groups. Neither NREm nor PREm exhibited significant phylogenetic signals, indicating that NREm and PREm were not phylogenetically conserved. NREm was not related to [N] in green leaves; PREm was positively correlated with [P] in green leaves; however, this relationship disappeared for different groups. NREm decreased with [N] in senescent leaves, PREm decreased with [P] in senescent leaves, for all species combined and for trees and shrubs. NREm decreased with soil inorganic N for all species and for shrubs; PREm did not exhibit a significant trend with soil available P for all species or for different plant groups. Neither NREm nor PREm was significantly related to MAT for overall species and for species of different groups.