Contrasting effects of N addition on the N and P status of understory vegetation in plantations of sapling and mature Larix principis-rupprechtii. (16th July 2018)

• Record Type: Journal Article
• Authors: Yan, Tao; Qu, Tiantian; Song, Huanhuan; Ciais, Philippe; Piao, Shilong; Sun, Zhenzhong; Zeng, Hui
• Is Part Of: Journal of plant ecology. Volume 11:Number 6(2018:Dec.)
• Page Start: 843
• Page End: 852
• Publication Date: 2018-07-16
• Subjects: larch plantation -- N addition -- nutrient resorption -- stand age -- understory species; Plant ecology -- Periodicals; Phytogeography -- Periodicals; 581.705
• DOI: 10.1093/jpe/rty023
• Languages: English
• ISSNs: 1752-9921

Abstract

Abstract: Aims: The productivity of forest plantations in temperate areas is often limited by nitrogen (N), but may shift towards phosphorus (P) limitation with increasing atmospheric N deposition. Nutrient resorption is a nutrient conservation strategy in plants. Although data on nutrient resorption are available for overstory trees, there are few data for understory vegetation. Methods: We examined leaf N and P concentrations and N and P resorption efficiencies (NRE and PRE, respectively) in eight understory species in 11- and 45-year-old Larix principis-rupprechtii stands subjected to N supplementation over a 3-year period. Important findings: Leaf N concentrations and N:P ratios increased and P concentrations decreased, with N input in species within the 45-year-old stand, but not in the 11-year-old stand. NRE and PRE were not altered by N input in any of the species in either stand, but N resorption proficiency decreased and P resorption proficiency increased, in the species in the 45-year-old stand. Thus, the growth of understory species may be more P-limited in the 45- versus 11-year-old stand, and nutrient resorption proficiency was more sensitive to N addition than nutrient resorption efficiency. These results will improve the understanding of nutrient use strategies and their responses to N addition in understory vegetation. The contrasting effects of N addition on nutrient status between stand ages cannot be ignored when modeling ecosystem nutrient cycling under global N deposition conditions.