土壤剖面碳氮稳定同位素自然丰度的垂直分布模式及其影响机制

doi:10.13287/j.1001-9332.202106.028

应用生态学报 ›› 2021, Vol. 32 ›› Issue (6): 1919-1927.doi: 10.13287/j.1001-9332.202106.028

• 稳定同位素生态学专栏 • 上一篇下一篇

土壤剖面碳氮稳定同位素自然丰度的垂直分布模式及其影响机制

陈淼^1,2, 刘顺^1,2, 许格希^1,2, 史作民^1,2,3*

¹中国林业科学研究院森林生态环境与保护研究所, 国家林业和草原局森林生态环境重点实验室, 北京 100091;
²四川米亚罗森林生态系统定位观测研究站, 四川理县 623100;
³南京林业大学南方现代林业协同创新中心, 南京 210037

收稿日期:2020-12-30 接受日期:2021-04-09 发布日期:2021-12-15
通讯作者: * E-mail: shizm@caf.ac.cn
作者简介:陈淼, 男, 1991年生, 博士研究生。主要从事稳定同位素生态学研究。E-mail: chenmiaocc@163.com
基金资助:
中央级公益性科研院所基本科研业务费专项(CAFYBB2018ZA003)和国家重点研发计划项目(2016YFC0502104-02)资助

Vertical distribution of natural abundance of stable carbon and nitrogen isotopes along the soil profile and the underlying mechanisms

CHEN Miao^1,2, LIU Shun^1,2, XU Ge-xi^1,2, SHI Zuo-min^1,2,3*

¹Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China;
²Miyaluo Research Station of Alpine Forest Ecosystem, Lixian 623100, Sichuan, China;
³Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China

Received:2020-12-30 Accepted:2021-04-09 Published:2021-12-15
Contact: * E-mail: shizm@caf.ac.cn
Supported by:
Special Fund of Chinese Central Government for Basic Scientific Research Operations in Commonweal Research Institutes (CAFYBB2018ZA003) and the National Key R&D Program of China (2016YFC0502104-02).

摘要/Abstract

摘要： 土壤碳、氮稳定同位素自然丰度(δ¹³C和δ¹⁵N)随土壤深度变化的研究,对揭示碳、氮元素生物地球化学循环机制具有重要意义。本文在概述土壤剖面δ¹³C和δ¹⁵N垂直分布特征的基础上,重点介绍了土壤δ¹³C和δ¹⁵N垂直分布模式的影响机制。土壤剖面δ¹³C垂直分布模式的影响机制主要有3种: 1)植被δ¹³C值的历史变化;2)植物群落C3-C4植物优势度变化;3)分解过程中¹³C富集的微生物源碳的积累。此外,讨论了¹³C休斯效应对土壤剖面δ¹³C垂直分布模式的影响。土壤剖面δ¹⁵N垂直分布模式的影响机制主要有4种: 1)反硝化过程产生的¹⁵N贫化气体的损失;2)分解过程中¹⁵N富集的微生物源氮的积累;3)菌根将¹⁵N贫化的含氮化合物转移到植物而在深层土壤积累¹⁵N富集的菌根真菌残留物;4)土壤有机质-矿物相互作用。最后提出了未来土壤剖面碳、氮稳定同位素自然丰度的垂直分布模式研究应该关注的重点。

关键词: 土壤剖面, 碳稳定同位素, 氮稳定同位素, 同位素分馏, 垂直分布

Abstract: Understanding the changes of natural abundance of stable carbon and nitrogen isotopes (δ¹³C and δ¹⁵N) along soil profile is of great importance in revealing the mechanisms of soil carbon and nitrogen cycling in terrestrial ecosystems. Based on a comprehensive review on the distribution of δ¹³C and δ¹⁵N along soil profile, the mechanisms underlying their vertical distribution were mainly introduced here. There were three mechanisms driving the δ¹³C vertical distribution in soil profile: 1) historical changes of vegetation δ¹³C value, 2) changes of C3-C4 species dominance in plant communities, 3) accumulation of ¹³C-enriched microbial-derived carbon during decomposition. The effects of ¹³C Suess effect on the vertical distribution of δ¹³C in soil profile were also discussed. There were four mechanisms underlying the vertical distribution of δ¹⁵N in soil profile: 1) ¹⁵N-depletion gas loss during denitrification, 2) accumulation of ¹⁵N-enriched microbial-derived nitrogen during decomposition, 3) accumulation of ¹⁵N-encriched mycorrhizal fungi residues in deep soil as a result of transferring ¹⁵N-depleted nitrogen compounds to plants by mycorrhizae, 4) intera-ction between soil organic matter and mineral substance. We proposed important concerning points for the future study on vertical distribution of natural abundance of stable carbon and nitrogen isotopes in soil profile.

Key words: soil profile, carbon stable isotope, nitrogen stable isotope, isotopic fractionation, vertical distribution

陈淼, 刘顺, 许格希, 史作民. 土壤剖面碳氮稳定同位素自然丰度的垂直分布模式及其影响机制[J]. 应用生态学报, 2021, 32(6): 1919-1927.

CHEN Miao, LIU Shun, XU Ge-xi, SHI Zuo-min. Vertical distribution of natural abundance of stable carbon and nitrogen isotopes along the soil profile and the underlying mechanisms[J]. Chinese Journal of Applied Ecology, 2021, 32(6): 1919-1927.

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土壤剖面碳氮稳定同位素自然丰度的垂直分布模式及其影响机制

Vertical distribution of natural abundance of stable carbon and nitrogen isotopes along the soil profile and the underlying mechanisms

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