Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (7): 932-942.DOI: 10.17521/cjpe.2022.0128

Special Issue: 生态化学计量 生态系统结构与功能 生物多样性

• Research Articles • Previous Articles     Next Articles

Effects of neighborhood tree species diversity on foliar nitrogen-phosphorus stoichiometry of Cunninghamia lanceolata

RAN Song-Song1, YU Zai-Peng1,*(), WAN Xiao-Hua1, FU Yan-Rong1, ZOU Bing-Zhang2, WANG Si-Rong2, HUANG Zhi-Qun1   

  1. 1School of Geographical Science, Cultivation Base of State Key Laboratory of Humid Subtropical Mountain Ecology, Fujian Normal University, Fuzhou 350007, China
    2Shanghang Baisha State-owned Forest Farm, Shanghang, Fujian 364305, China
  • Received:2022-04-08 Accepted:2022-10-11 Online:2023-07-20 Published:2023-07-21
  • Contact: *YU Zai-Peng(zaipengyu@fjnu.edu.cn)
  • Supported by:
    The National Natural Science Foundation of China(31930077);The National Natural Science Foundation of China(31625007);The National Natural Science Foundation of China(31901162);The China Postdoctoral Science Foundation(2020T130100)

Abstract:

Aims Biodiversity loss threatens ecosystem functions. Investigating the effect of biodiversity on the ecological stoichiometry of plant nutrients, therefore, can help reveal the mechanisms of the effect of biodiversity on ecosystem functions.

Methods Using a tree species diversity experiment in subtropical China, Cunninghamia lanceolatafrom plots with different tree species richness (1, 4, 8, 16, 32) were selected as focal tree species. The effects of neighborhood species richness (NSR), functional trait dissimilarities between neighborhood tree species and the focal tree, neighborhood competition index (NCI) on foliar nitrogen (N), phosphorus (P) content and N:P of C. lanceolata were investigated.

Important findings (1) The results showed that the dissimilarity in specific root length (SRL_diss) between neighborhood trees and focal trees significantly increased the foliar P content of C. lanceolata, while the dissimilarity in root tissue density (RTD_diss) significantly decreased the foliar N content of C. lanceolata. (2) Neighborhood competition significantly decreased the foliar N content and N:P of C. lanceolata. (3) The interaction effects of NCI and SRL_diss, as well as the interaction between NSR and SRL_diss significantly reduced the foliar P content of C. lanceolata. The result indicates that the positive effect of SRL_diss on the foliar P content of C. lanceolata decreased with increasing NSR, and the positive effect of SRL_diss on the foliar P content of C. lanceolata decreased with increasing NCI. (4) The interaction between NSR and phylogenetic dissimilarity (NP_diss) significantly increased foliar N:P of C. lanceolata, demonstrating that the negative effect of NP_diss on the foliar N:P content of C. lanceolata decreased with increasing NSR. Our results indicated that the foliar P content of C. lanceolata was significantly enhanced by mixing with tree species with different trait dissimilarities, while foliar N content of C. lanceolata was decreased by neighborhood competition. Tree species richness can help mitigate the adverse effects of interspecific competition on C. lanceolata through niche complementation when mixing with species that have greater trait dissimilarity.

Key words: tree species richness, trait dissimilarity, niche complementarity, competition, nutrient