Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil

Research output: Contribution to journal › Article › Research › peer review

Authors

Research Organisations

External Research Organisations

  • Institute of Subtropical Agriculture, Chinese Academy of Sciences
  • Lund University
  • Ningbo University
  • Ludong University
  • Russian Academy of Sciences (RAS)
View graph of relations

Details

Original languageEnglish
Pages (from-to)1193-1203
Number of pages11
JournalLand Degradation and Development
Volume33
Issue number8
Early online date4 May 2022
Publication statusPublished - 15 May 2022

Abstract

Root exudates can significantly modify microbial activity and soil organic matter (SOM) mineralization. However, how root exudates and their C/N stoichiometric ratios control rice field (paddy) soil C mineralization is poorly understood. This study used a mixture of glucose, oxalic acid, and alanine as root exudate mimics for three C/N stoichiometric ratios (CN6, CN10, and CN80) to explore the underlying mechanisms involved in SOM mineralization. The input of root exudates enhanced CO2 emissions by 1.8–2.3-fold that of soil with only C additions (C-only). Artificial root exudates with low C/N ratios (CN6 and CN10) increased the metabolic quotient (qCO2) by 12% over those with higher stoichiometric ratios (CN80 and C-only), suggesting a relatively high energy demand for microorganisms to acquire organic N from SOM by increasing N-hydrolase production. The increase of stoichiometric ratios of C- to N-hydrolase [β-1,4-glucosidase to β-1,4-N-acetyl glucosaminidase (NAG)] promoted SOM degradation compared to those involved in organic C- and N-degradation, which had a significant positive correlation with qCO2. The stoichiometric ratios of microbial biomass were positively correlated with C use efficiency, indicating root exudates with higher C/N ratios provide an undersupply of N for microorganisms that trigger the release of N-degrading extracellular enzymes. Our findings showed that the C/N stoichiometry of root exudates controlled SOM mineralization by affecting the specific response of the microbial biomass through the activity of C- and N-releasing extracellular enzymes to adjust the microbial C/N ratio.

Keywords

    carbon use efficiency, extracellular enzymes, metabolic quotients, microbial biomass, root exudates, stoichiometric ratios

ASJC Scopus subject areas

Cite this

Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil. / Cai, Guan; Shahbaz, Muhammad; Ge, Tida et al.
In: Land Degradation and Development, Vol. 33, No. 8, 15.05.2022, p. 1193-1203.

Research output: Contribution to journal › Article › Research › peer review

Cai, G, Shahbaz, M, Ge, T, Hu, Y, Li, B, Yuan, H, Wang, Y, Liu, Y, Liu, Q, Shibistova, O, Sauheitl, L, Wu, J, Guggenberger, G & Zhu, Z 2022, 'Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil', Land Degradation and Development, vol. 33, no. 8, pp. 1193-1203. https://doi.org/10.1002/ldr.4198
Cai, G., Shahbaz, M., Ge, T., Hu, Y., Li, B., Yuan, H., Wang, Y., Liu, Y., Liu, Q., Shibistova, O., Sauheitl, L., Wu, J., Guggenberger, G., & Zhu, Z. (2022). Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil. Land Degradation and Development, 33(8), 1193-1203. https://doi.org/10.1002/ldr.4198
Cai G, Shahbaz M, Ge T, Hu Y, Li B, Yuan H et al. Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil. Land Degradation and Development. 2022 May 15;33(8):1193-1203. Epub 2022 May 4. doi: 10.1002/ldr.4198
Cai, Guan ; Shahbaz, Muhammad ; Ge, Tida et al. / Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil. In: Land Degradation and Development. 2022 ; Vol. 33, No. 8. pp. 1193-1203.
Download
@article{f5a709ba62ff4bd48fb4c830e298f211,
title = "Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil",
abstract = "Root exudates can significantly modify microbial activity and soil organic matter (SOM) mineralization. However, how root exudates and their C/N stoichiometric ratios control rice field (paddy) soil C mineralization is poorly understood. This study used a mixture of glucose, oxalic acid, and alanine as root exudate mimics for three C/N stoichiometric ratios (CN6, CN10, and CN80) to explore the underlying mechanisms involved in SOM mineralization. The input of root exudates enhanced CO2 emissions by 1.8–2.3-fold that of soil with only C additions (C-only). Artificial root exudates with low C/N ratios (CN6 and CN10) increased the metabolic quotient (qCO2) by 12% over those with higher stoichiometric ratios (CN80 and C-only), suggesting a relatively high energy demand for microorganisms to acquire organic N from SOM by increasing N-hydrolase production. The increase of stoichiometric ratios of C- to N-hydrolase [β-1,4-glucosidase to β-1,4-N-acetyl glucosaminidase (NAG)] promoted SOM degradation compared to those involved in organic C- and N-degradation, which had a significant positive correlation with qCO2. The stoichiometric ratios of microbial biomass were positively correlated with C use efficiency, indicating root exudates with higher C/N ratios provide an undersupply of N for microorganisms that trigger the release of N-degrading extracellular enzymes. Our findings showed that the C/N stoichiometry of root exudates controlled SOM mineralization by affecting the specific response of the microbial biomass through the activity of C- and N-releasing extracellular enzymes to adjust the microbial C/N ratio.",
keywords = "carbon use efficiency, extracellular enzymes, metabolic quotients, microbial biomass, root exudates, stoichiometric ratios",
author = "Guan Cai and Muhammad Shahbaz and Tida Ge and Yajun Hu and Baozhen Li and Hongzhao Yuan and Yi Wang and Yuhuai Liu and Qiong Liu and Olga Shibistova and Leopold Sauheitl and Jinshui Wu and Georg Guggenberger and Zhenke Zhu",
note = "Funding information: National Natural Science Foundation of China, Grant/Award Numbers: 41877104, 41977156, 42177330, 42177334; the Alexander von Humboldt Foundation of Germany, Grant/Award Number: The grants or other support to Tida Ge from the Al; the Natural Science Foundation of Hunan Province, Grant/Award Number: 2020JJ4653; The Youth Innovation Promotion Association of the Chinese Academy of Sciences, Grant/Award Number: 2019357",
year = "2022",
month = may,
day = "15",
doi = "10.1002/ldr.4198",
language = "English",
volume = "33",
pages = "1193--1203",
journal = "Land Degradation and Development",
issn = "1085-3278",
publisher = "John Wiley and Sons Ltd",
number = "8",

}

Download

TY - JOUR

T1 - Root exudates with low C/N ratios accelerate CO2 emissions from paddy soil

AU - Cai, Guan

AU - Shahbaz, Muhammad

AU - Ge, Tida

AU - Hu, Yajun

AU - Li, Baozhen

AU - Yuan, Hongzhao

AU - Wang, Yi

AU - Liu, Yuhuai

AU - Liu, Qiong

AU - Shibistova, Olga

AU - Sauheitl, Leopold

AU - Wu, Jinshui

AU - Guggenberger, Georg

AU - Zhu, Zhenke

N1 - Funding information: National Natural Science Foundation of China, Grant/Award Numbers: 41877104, 41977156, 42177330, 42177334; the Alexander von Humboldt Foundation of Germany, Grant/Award Number: The grants or other support to Tida Ge from the Al; the Natural Science Foundation of Hunan Province, Grant/Award Number: 2020JJ4653; The Youth Innovation Promotion Association of the Chinese Academy of Sciences, Grant/Award Number: 2019357

PY - 2022/5/15

Y1 - 2022/5/15

N2 - Root exudates can significantly modify microbial activity and soil organic matter (SOM) mineralization. However, how root exudates and their C/N stoichiometric ratios control rice field (paddy) soil C mineralization is poorly understood. This study used a mixture of glucose, oxalic acid, and alanine as root exudate mimics for three C/N stoichiometric ratios (CN6, CN10, and CN80) to explore the underlying mechanisms involved in SOM mineralization. The input of root exudates enhanced CO2 emissions by 1.8–2.3-fold that of soil with only C additions (C-only). Artificial root exudates with low C/N ratios (CN6 and CN10) increased the metabolic quotient (qCO2) by 12% over those with higher stoichiometric ratios (CN80 and C-only), suggesting a relatively high energy demand for microorganisms to acquire organic N from SOM by increasing N-hydrolase production. The increase of stoichiometric ratios of C- to N-hydrolase [β-1,4-glucosidase to β-1,4-N-acetyl glucosaminidase (NAG)] promoted SOM degradation compared to those involved in organic C- and N-degradation, which had a significant positive correlation with qCO2. The stoichiometric ratios of microbial biomass were positively correlated with C use efficiency, indicating root exudates with higher C/N ratios provide an undersupply of N for microorganisms that trigger the release of N-degrading extracellular enzymes. Our findings showed that the C/N stoichiometry of root exudates controlled SOM mineralization by affecting the specific response of the microbial biomass through the activity of C- and N-releasing extracellular enzymes to adjust the microbial C/N ratio.

AB - Root exudates can significantly modify microbial activity and soil organic matter (SOM) mineralization. However, how root exudates and their C/N stoichiometric ratios control rice field (paddy) soil C mineralization is poorly understood. This study used a mixture of glucose, oxalic acid, and alanine as root exudate mimics for three C/N stoichiometric ratios (CN6, CN10, and CN80) to explore the underlying mechanisms involved in SOM mineralization. The input of root exudates enhanced CO2 emissions by 1.8–2.3-fold that of soil with only C additions (C-only). Artificial root exudates with low C/N ratios (CN6 and CN10) increased the metabolic quotient (qCO2) by 12% over those with higher stoichiometric ratios (CN80 and C-only), suggesting a relatively high energy demand for microorganisms to acquire organic N from SOM by increasing N-hydrolase production. The increase of stoichiometric ratios of C- to N-hydrolase [β-1,4-glucosidase to β-1,4-N-acetyl glucosaminidase (NAG)] promoted SOM degradation compared to those involved in organic C- and N-degradation, which had a significant positive correlation with qCO2. The stoichiometric ratios of microbial biomass were positively correlated with C use efficiency, indicating root exudates with higher C/N ratios provide an undersupply of N for microorganisms that trigger the release of N-degrading extracellular enzymes. Our findings showed that the C/N stoichiometry of root exudates controlled SOM mineralization by affecting the specific response of the microbial biomass through the activity of C- and N-releasing extracellular enzymes to adjust the microbial C/N ratio.

KW - carbon use efficiency

KW - extracellular enzymes

KW - metabolic quotients

KW - microbial biomass

KW - root exudates

KW - stoichiometric ratios

UR - http://www.scopus.com/inward/record.url?scp=85127414234&partnerID=8YFLogxK

U2 - 10.1002/ldr.4198

DO - 10.1002/ldr.4198

M3 - Article

AN - SCOPUS:85127414234

VL - 33

SP - 1193

EP - 1203

JO - Land Degradation and Development

JF - Land Degradation and Development

SN - 1085-3278

IS - 8

ER -

By the same author(s)

  1. Census of below-ground biota associated with permafrost affected soils of western Greenland, with a focus on trophic structure

    Research output: Contribution to journal › Article › Research › peer review

  2. Acidification of European croplands by nitrogen fertilization: Consequences for carbonate losses, and soil health

    Research output: Contribution to journal › Article › Research › peer review

  3. Long-term soil redox dynamics of intact and degraded permafrost in Interior Alaska

    Research output: Contribution to conference › Paper › Research

  4. The “extra pinch” of pseudosand to enhance tropical biogeochemical processes understanding

    Research output: Contribution to journal › Editorial in journal › Research › peer review

  5. Alternate wetting-drying had no preferences for rice P uptake but increased microbial P allocation to phospholipids: Evidence from dual 32P and 33P labeling

    Research output: Contribution to journal › Article › Research › peer review