植物生态学报 ›› 2025, Vol. 49 ›› Issue (2): 244-255.DOI: 10.17521/cjpe.2024.0211  cstr: 32100.14.cjpe.2024.0211

• 研究论文 • 上一篇    下一篇

武夷山不同海拔杉木凋落叶和细根分解规律以及驱动因素的差异

郑琳敏, 熊小玲, 姜永孟, 王曼, 张锦秀, 曾志伟, 吕茂奎*(), 谢锦升   

  1. 福建师范大学地理科学学院, 福建师范大学湿润亚热带生态地理过程教育部重点实验室, 福州 350117
  • 收稿日期:2024-07-01 接受日期:2024-12-24 出版日期:2025-02-20 发布日期:2025-02-20
  • 通讯作者: *吕茂奎: (228lmk@163.com)
  • 基金资助:
    国家自然科学基金(32371659);国家自然科学基金(32001169)

Decomposition regularities of leaf litter and fine roots of Cunninghamia lanceolata and their divergent drivers at different altitudes in the Wuyi Mountain

ZHENG Lin-Min, XIONG Xiao-Ling, JIANG Yong-Meng, WANG Man, ZHANG Jin-Xiu, ZENG Zhi-Wei, LYU Mao-Kui*(), XIE Jin-Sheng   

  1. College of Geographical Science, Fujian Normal University, Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, Fujian Normal University, Fuzhou 350117, China
  • Received:2024-07-01 Accepted:2024-12-24 Online:2025-02-20 Published:2025-02-20
  • Supported by:
    National Natural Science Foundation of China(32371659);National Natural Science Foundation of China(32001169)

摘要:

凋落物是森林土壤有机质的重要来源, 凋落物分解在全球碳循环过程中至关重要。武夷山具有较大的地势起伏, 沿海拔梯度形成了各种各样的植被类型和生态系统。研究不同海拔杉木凋落叶和细根的分解规律和驱动因素的差异, 可为研究区生态系统保护和管理提供一定的科学理论依据。鉴于此, 该研究选择了武夷山的不同海拔山地杉木(Cunninghamia lanceolata)人工林作为气候变化研究平台, 采用分解袋法开展了为期3.5年的杉木凋落叶和细根凋落物分解实验。主要结果: (1)同一海拔凋落叶的分解速率高于细根, 且海拔升高会降低凋落叶和细根的分解速率, 增大凋落叶与细根分解速率的差异。(2)海拔的升高会降低凋落叶和细根碳、氮、磷的释放速率, 对凋落物中木质素的分解也具有抑制作用。(3)不同海拔高度的温度差异驱动细根的分解和养分变化, 而不同海拔高度上土壤养分和微生物的变化主要作用于凋落叶。该研究探讨了温度、土壤以及微生物如何作用于凋落叶和细根的分解, 加深了对同一树种的地上和地下凋落物分解及其对气候变化响应差异的认识。

关键词: 凋落叶, 细根, 分解速率, 养分释放, 海拔, 杉木

Abstract:

Aims Litter is an important source of organic matter in forest soils, and litter decomposition is crucial in the global carbon cycle. There is a large topographic relief that has formed various vegetation types and ecosystems along the altitudinal gradient in the Wuyi Mountain, China. Studying the differences in the decomposition regularities and driving factors of leaf litter and fine roots of Cunninghamia lanceolata at different altitudes can provide scientific theoretical basis for protecting and managing ecosystems in the study area.

Methods In this study, C. lanceolata plantation forests at three altitudes in the Wuyi Mountain were selected as the research platform for climate change research. A 3.5-year-experiment on litter and fine root decomposition was conducted using the decomposition bag approach along the altitude gradient.

Important findings The decomposition rate of leaf litter was higher than that of fine roots across the altitude gradient. The decomposition rates of leaf litter and fine roots decreased with increasing altitude, while we observed increased differences in decomposition rates between leaf litter and fine roots. Furthermore, the release rates of carbon, nitrogen, and phosphorus from leaf litter and fine roots reduced with increasing altitude, which had an inhibitory effect on lignin decomposition in litter and roots. The temperature was found to drive fine root decomposition and nutrient changes, while soil nutrient status and microbial communities across the altitudinal gradient acted primarily on leaf litter, suggesting divergent drivers controlling litter and root decomposition across the altitude gradient. Taken together, this study explores the impact of temperature, soil, and microorganisms on leaf litter and fine root decomposition, thereby deepening the understanding of differences in aboveground and belowground litter decomposition of the same tree species and their response to climate change.

Key words: leaf litter, fine root, decomposition rate, nutrient release, altitude, Cunninghamia lanceolata