J Plant Ecol ›› 2018, Vol. 11 ›› Issue (6): 843-852.DOI: 10.1093/jpe/rty023

• Research Articles • Previous Articles     Next Articles

Contrasting effects of N addition on the N and P status of understory vegetation in plantations of sapling and mature Larix principis-rupprechtii

Tao Yan1, Tiantian Qu2, Huanhuan Song3, Philippe Ciais4, Shilong Piao1,5,6, Zhenzhong Sun2,1 and Hui Zeng2,*   

  1. 1 Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, 5 Yiheyuan Road, Haidian District, Beijing 100871, China
    2 School of Urban Planning and Design, Peking University, 2199 Lishui Road, Nanshan District, Shenzhen 518055, China
    3 Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenhe District, Shenyang 110016, China
    4 Laboratoire des Sciences du Climat et de l’Environnement, UMR 1572 CEA-CNRS-UVSQ, 91191 Gif-sur-Yvette, France
    5 Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 16 Lincui Road, Chaoyang District, Beijing 100085, China
    6 Center for Excellence in Tibetan Earth Science, Chinese Academy of Sciences, 16 Lincui Road, Chaoyang District, Beijing
    100085, China
    *Correspondence address. School of Urban Planning and Design, Peking University Shenzhen University Town, 2199 Lishui Road, Nanshan District, Shenzhen, Guangdong 518055, China. Tel: +86-755-26035585; Fax: +86-10-26035585; E-mail: zengh@pkusz.edu.cn
  • Received:2018-01-25 Revised:2018-06-24 Accepted:2018-07-13 Online:2018-06-16 Published:2018-12-21

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.

Key words: larch plantation, N addition, nutrient resorption, stand age, understory species