作 者：
Zhang Changshun;Chunlan Liu;Wenyuan Zhang;Gaogang Xie;Shaohui Fan;Na L
单 位：
International Centre for Bamboo and Rattan, Beijing, People’s Republic of China;University of Chinese Academy of Sciences, Beijing, People's Republic of China#TAB;Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, People’s Republic of China;Beijing Municipal Research Institute of Environmental Protection, Beijing, People’s Republic of China;College of Landscape and Art, Jiangxi Agricultural University, Nanchang, People’s Republic of China
关键词：
Phyllostachys edulis;Nitrogen resorption efficiency;Nitrogen resorption proficiency;Nitrogen-use efficiency;Extensive management;Culm development;Precision fertilization;LEAF LIFE-SPAN;NUTRIENT RESORPTION;USE EFFICIENCY;RETRANSLOCATION EFFICIENCY;CONSERVATION STRATEGIES;SENESCING LEAVES;PLANT;AGE;DECOMPOSITION;PHOSPHORU
摘 要：
Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms. However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations (N-m), nitrogen resorption efficiency (NRE) and proficiency (NRP or N-s) and leaf-level nitrogen use efficiency (NUE) of the current-, 3rd- and 5th-year culms in P. edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of N-m, NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. N-m, N-s and NRE were significant higher in younger (current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older (3rd- or 5th-year) culms with 2-year lifespan leaves. Significant linear correlations between N-m and NRP, NRE and NUE, N-m and NUE, N-s and NRE were found for each culm age, and N-m was significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by N-m, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP, and leaf-level NUE in concert with culm development. Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.
