Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (5): 629-643.DOI: 10.17521/cjpe.2022.0063

• Research Articles • Previous Articles     Next Articles

Effects of nitrogen addition and litter manipulations on leaf litter decomposition in western edge of Sichuan Basin, China

ZHONG Qi1, LI Zeng-Yan2, MA Wei1, KUANG Yu-Xiao1, QIU Ling-Jun1, LI Yun-Jie1, TU Li-Hua1,*()   

  1. 1. National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River, College of Forestry, Sichuan Agricultural University, Chengdu 611130, China
    2. College of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
  • Received:2022-02-16 Accepted:2022-07-15 Online:2023-05-20 Published:2022-07-18
  • Supported by:
    National Natural Science Foundation of China(32071591)

Abstract:

Aims The purpose of this study is to examine the responses of litter decomposition to nitrogen (N) deposition and aboveground litter manipulation.
Methods A two-factor experiment of N addition and litterfall manipulation was performed in a N saturation evergreen broadleaf forest on the western edge of the Sichuan Basin in China from June 2014 to June 2019. We conducted three levels of N addition, including an N control (CK, ambient N input), low N (LN, 50 kg·hm-2·a-1) and high N (HN, 150 kg·hm-2·a-1), and three levels of litterfall manipulation, including intact litter input (L0, no litter alteration), litter reduction (L-, reduced by 50%) and litter addition (L+, increased by 50%).
Important findings We found six-year N addition did not significantly alter the aboveground litter input in the studied forest ecosystem. N addition significantly inhibited leaf litter decomposition, with the leaf litter decomposition significantly decreased in high N treatment. N addition significantly reduced the remaining rate of manganese (Mn) in the late stage and promoted the release of Mn. Litter manipulation did not significantly alter the rate of leaf litter decomposition, but increased the remaining rate of Mn in the litter and slowed down the release of Mn. There was no significant interactive effect between N addition and litter manipulation. This study showed that N addition affected litter decomposition in subtropical N-saturated evergreen broadleaf forests by directly affecting litter decomposition, while litter manipulation mainly affected the content of Mn during litter decomposition. Therefore, the content of Mn of litter may play a key role in the process of litter decomposition in response to N input.

Key words: nitrogen deposition, litter manipulation, leaf litter decomposition, remaining of nutrient, subtropical evergreen broadleaf forest