Journal of Ecosystem & Ecography
Open Access

Abstract

Leaf N, P contents and nutrient resorption patterns have the potential to reflect gradients in plant nutrient limitation and to affect a suite of terrestrial ecosystem functions. Green-leaf and senesced-leaf N and P concentrations were quantified for 102 species and 47 species respectively from 70 plots in phosphorus-enriched regions of the Lake Dianchi watershed, southwestern China. The average values of contents of Green-leaf N, P and N: P were 17.98mg/g, 4.29mg/g and 4.64. Leaf nutrient concentration was significantly higher in forbs plants than in woody plants, but there was no difference in leaf nutrient concentrations between trees and shrubs. The average values of contents of senesced-leaf N, P and N: P were 7.05mg/g, 2.64mg/g, and 3.10. The N resorption efficiency (NRE) ranged from 27.06% to 84.38%, and mean value is 55.4%; The P resorption efficiency (PRE) ranged from 2.01% to 56.31%, and mean value is 24.75%. PRE in our research was lower than other works around the world. Forbs had the lowest PRE. Green-leaf N was positive related to green-leaf P, but senesced-N was less related to senesced-N. Standardized major axis analyses showed that the relationship between foliar N and P content was different from phosphorus-enriched region to normal region. With the increasing of green-leaf N, senesced-N increased. And also, with the increasing of green-leaf P, senesced-P increased. Green-leaf N: P was positive correlation between with senesced-N, but negative with senesced-P. Results suggested that plant growth and vegetation development in the Lake Dianchi watershed were limited by low soil N contents and plant growth enhanced by N addition should be important for vegetation resilience.

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