近日，中国科学院地理科学与资源研究所寇亮团队研究了年代际尺度上森林土壤中吸收细根的大量碳积累。相关论文于2025年9月23日发表在《自然—地球科学》杂志上。

森林土壤拥有最大的陆地碳库，来源于死亡的植物组织并由土壤生物群转化。目前的框架强调土壤微生物在高度持久的碳形式中的作用。然而，中等持久性的碳形式也通过植物凋落物输入和输出在几十年时间尺度上的迭代效应对森林土壤碳库做出了重大贡献。这些土壤碳的强度并没有得到很好的限制。

研究组综合了北半球主要森林生态系统类型菌根木本植物最细根（吸收根）的已发表的野外数据。他们估计，由于快速的周转和缓慢的分解，超过20年的时间内，吸收根对土壤碳累积的迭代效应产生2.4 ± 0.1 MgC ha⁻¹，超过叶片65%。此外，尽管外生菌根林在森林土壤中总体上主导着土壤碳储量，但与丛枝菌根真菌相关的根比与外生菌根真菌相关的根贡献的土壤碳多43%。研究组还发现，特定的根长度（一个容易测量的特性），可以作为与根动力学相关的迭代效应的代理指标。该发现为地球系统中的碳模型提供了一个长期需要的地下度量。

附：英文原文

Title: Substantial forest soil carbon accrual from absorptive fine roots over decadal timescales

Author: Ma, Ning, Li, Shenggong, McCormack, M. Luke, Freschet, Grgoire T., Ciais, Philippe, Wang, Huimin, Niu, Shuli, Reich, Peter B., Zhang, Miaomiao, Zhao, Rongtian, Zhao, Bo, Gao, Decai, Gessler, Arthur, Huang, Yuanyuan, Gu, Jiacun, Fu, Xiaoli, Dai, Xiaoqin, Meng, Shengwang, Zheng, Jiajia, Yang, Fengting, Kou, Liang

Issue&Volume: 2025-09-23

Abstract: Forest soils hold the largest terrestrial carbon pool, derived from dead plant tissues and transformed by soil biota. Current frameworks emphasize the role of soil microbes in highly persistent forms of carbon. However, moderately persistent forms of carbon also contribute substantially to forest soil carbon pools through the iterative effects of plant litter inputs and outputs over multi-decadal timescales. These sources of soil carbon are not well constrained. Here we synthesize published field data of the finest roots (absorptive roots) of mycorrhizal woody plants across major forest ecosystem types in the Northern Hemisphere. We estimate that, owing to fast turnover and slow decomposition, the iterative effects of absorptive roots on soil carbon accrual generate 2.4±0.1MgCha1 over two decades, exceeding that of leaves by 65%. Further, roots associated with arbuscular mycorrhizal fungi contribute 43% more soil carbon than roots associated with ectomycorrhizal fungi, despite ectomycorrhizal forests dominating soil carbon storage in forest soils overall. We also find that specific root length, a readily measured trait, can be used as a proxy for iterative effects associated with root dynamics. Our findings thus provide a long-needed belowground metric for carbon modelling in the Earth system.

DOI: 10.1038/s41561-025-01790-5

Source: https://www.nature.com/articles/s41561-025-01790-5