Microbial responses to the erosional redistribution of soil organic carbon in arable fields

Jennifer A. J. Dungait*, Claire Ghee, John S. Rowan, Blair M. McKenzie, Cathy Hawes, Elizabeth R. Dixon, Eric Paterson, David W. Hopkins

*Corresponding author for this work

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

Quantifying the potential for eroding agricultural soils to act as sinks or sources of atmospheric carbon relies on accounting for the pools and fluxes of soil organic carbon (SOC) and nutrients, e.g. nitrogen (N), affected by erosion. Herein, we report the outcomes of an experiment where a C-4 maize (Zea mays) crop (delta C-13 = -12.1 parts per thousand,) was cultivated and incorporated for 2 years to introduce a 'pulse' of C-13-enriched SOC to a C-3 arable soil (delta C-13 = -27.4 parts per thousand). Soils were sampled at eroding (top slope and upper slope) and depositional (lower slope and slope foot) positions of an accelerated erosion pathway that were confirmed using Cs-137 measurements. The sand particle-sized fraction (63-2000 mu m) was predominant and increased in the depositional slope positions due to selective loss of fine particles and preferential deposition of the coarsest fraction of transported sediment. There was a significant isometric relationship between the percentage SOC and total N: top slope > upper slope > lower slope, with similar values in the slope foot to the top slope. The delta N-15 values of the soils were enriched (7.3 parts per thousand) at the slope foot, compared with the other slope positions (average 6.3 parts per thousand), suggesting increased denitrification rates. The delta C-13 values of the soil microbial biomass C extracted from surface soils (0-5 cm) at each slope position showed that the proportion of maize C being incorporated into the soil microbial biomass declined in the downslope direction from 54% (top slope) to 43% (upper slope) to 18% (lower slope) in inverse proportion to the size of the soil microbial biomass, and increased to 41% at the slope foot. This suggests dynamic replacement of the SOC with crop C in the eroding slope positions and dilution of the transported C by C3-SOC in the depositional slope positions. This paper is evidence that erosional distribution of soil carbon leads to differential microbial utilisation of SOC between eroding and depositional sites. (C) 2013 Elsevier Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)195-201
Number of pages7
JournalSoil Biology and Biochemistry
Volume60
Early online date16 Feb 2013
DOIs
Publication statusPublished - May 2013

Keywords

  • soil erosion
  • agriculture
  • soil microbial biomass
  • carbon cycling
  • nitrogen cycling
  • landscape-scale variations
  • N-15 natural-abundance
  • tillage erosion
  • climate-change
  • matter
  • biomass
  • plant
  • delta-C-13
  • turnover
  • dynamics

Cite this

Dungait, J. A. J., Ghee, C., Rowan, J. S., McKenzie, B. M., Hawes, C., Dixon, E. R., ... Hopkins, D. W. (2013). Microbial responses to the erosional redistribution of soil organic carbon in arable fields. Soil Biology and Biochemistry, 60, 195-201. https://doi.org/10.1016/j.soilbio.2013.01.027

Microbial responses to the erosional redistribution of soil organic carbon in arable fields. / Dungait, Jennifer A. J.; Ghee, Claire; Rowan, John S.; McKenzie, Blair M.; Hawes, Cathy; Dixon, Elizabeth R.; Paterson, Eric; Hopkins, David W.

In: Soil Biology and Biochemistry, Vol. 60, 05.2013, p. 195-201.

Research output: Contribution to journalArticle

Dungait, JAJ, Ghee, C, Rowan, JS, McKenzie, BM, Hawes, C, Dixon, ER, Paterson, E & Hopkins, DW 2013, 'Microbial responses to the erosional redistribution of soil organic carbon in arable fields', Soil Biology and Biochemistry, vol. 60, pp. 195-201. https://doi.org/10.1016/j.soilbio.2013.01.027
Dungait, Jennifer A. J. ; Ghee, Claire ; Rowan, John S. ; McKenzie, Blair M. ; Hawes, Cathy ; Dixon, Elizabeth R. ; Paterson, Eric ; Hopkins, David W. / Microbial responses to the erosional redistribution of soil organic carbon in arable fields. In: Soil Biology and Biochemistry. 2013 ; Vol. 60. pp. 195-201.
@article{8a56e023dfac4af487c7c8597a091503,
title = "Microbial responses to the erosional redistribution of soil organic carbon in arable fields",
abstract = "Quantifying the potential for eroding agricultural soils to act as sinks or sources of atmospheric carbon relies on accounting for the pools and fluxes of soil organic carbon (SOC) and nutrients, e.g. nitrogen (N), affected by erosion. Herein, we report the outcomes of an experiment where a C-4 maize (Zea mays) crop (delta C-13 = -12.1 parts per thousand,) was cultivated and incorporated for 2 years to introduce a 'pulse' of C-13-enriched SOC to a C-3 arable soil (delta C-13 = -27.4 parts per thousand). Soils were sampled at eroding (top slope and upper slope) and depositional (lower slope and slope foot) positions of an accelerated erosion pathway that were confirmed using Cs-137 measurements. The sand particle-sized fraction (63-2000 mu m) was predominant and increased in the depositional slope positions due to selective loss of fine particles and preferential deposition of the coarsest fraction of transported sediment. There was a significant isometric relationship between the percentage SOC and total N: top slope > upper slope > lower slope, with similar values in the slope foot to the top slope. The delta N-15 values of the soils were enriched (7.3 parts per thousand) at the slope foot, compared with the other slope positions (average 6.3 parts per thousand), suggesting increased denitrification rates. The delta C-13 values of the soil microbial biomass C extracted from surface soils (0-5 cm) at each slope position showed that the proportion of maize C being incorporated into the soil microbial biomass declined in the downslope direction from 54{\%} (top slope) to 43{\%} (upper slope) to 18{\%} (lower slope) in inverse proportion to the size of the soil microbial biomass, and increased to 41{\%} at the slope foot. This suggests dynamic replacement of the SOC with crop C in the eroding slope positions and dilution of the transported C by C3-SOC in the depositional slope positions. This paper is evidence that erosional distribution of soil carbon leads to differential microbial utilisation of SOC between eroding and depositional sites. (C) 2013 Elsevier Ltd. All rights reserved.",
keywords = "soil erosion, agriculture, soil microbial biomass, carbon cycling, nitrogen cycling, landscape-scale variations, N-15 natural-abundance, tillage erosion, climate-change, matter, biomass, plant, delta-C-13, turnover, dynamics",
author = "Dungait, {Jennifer A. J.} and Claire Ghee and Rowan, {John S.} and McKenzie, {Blair M.} and Cathy Hawes and Dixon, {Elizabeth R.} and Eric Paterson and Hopkins, {David W.}",
year = "2013",
month = "5",
doi = "10.1016/j.soilbio.2013.01.027",
language = "English",
volume = "60",
pages = "195--201",
journal = "Soil Biology and Biochemistry",
issn = "0038-0717",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Microbial responses to the erosional redistribution of soil organic carbon in arable fields

AU - Dungait, Jennifer A. J.

AU - Ghee, Claire

AU - Rowan, John S.

AU - McKenzie, Blair M.

AU - Hawes, Cathy

AU - Dixon, Elizabeth R.

AU - Paterson, Eric

AU - Hopkins, David W.

PY - 2013/5

Y1 - 2013/5

N2 - Quantifying the potential for eroding agricultural soils to act as sinks or sources of atmospheric carbon relies on accounting for the pools and fluxes of soil organic carbon (SOC) and nutrients, e.g. nitrogen (N), affected by erosion. Herein, we report the outcomes of an experiment where a C-4 maize (Zea mays) crop (delta C-13 = -12.1 parts per thousand,) was cultivated and incorporated for 2 years to introduce a 'pulse' of C-13-enriched SOC to a C-3 arable soil (delta C-13 = -27.4 parts per thousand). Soils were sampled at eroding (top slope and upper slope) and depositional (lower slope and slope foot) positions of an accelerated erosion pathway that were confirmed using Cs-137 measurements. The sand particle-sized fraction (63-2000 mu m) was predominant and increased in the depositional slope positions due to selective loss of fine particles and preferential deposition of the coarsest fraction of transported sediment. There was a significant isometric relationship between the percentage SOC and total N: top slope > upper slope > lower slope, with similar values in the slope foot to the top slope. The delta N-15 values of the soils were enriched (7.3 parts per thousand) at the slope foot, compared with the other slope positions (average 6.3 parts per thousand), suggesting increased denitrification rates. The delta C-13 values of the soil microbial biomass C extracted from surface soils (0-5 cm) at each slope position showed that the proportion of maize C being incorporated into the soil microbial biomass declined in the downslope direction from 54% (top slope) to 43% (upper slope) to 18% (lower slope) in inverse proportion to the size of the soil microbial biomass, and increased to 41% at the slope foot. This suggests dynamic replacement of the SOC with crop C in the eroding slope positions and dilution of the transported C by C3-SOC in the depositional slope positions. This paper is evidence that erosional distribution of soil carbon leads to differential microbial utilisation of SOC between eroding and depositional sites. (C) 2013 Elsevier Ltd. All rights reserved.

AB - Quantifying the potential for eroding agricultural soils to act as sinks or sources of atmospheric carbon relies on accounting for the pools and fluxes of soil organic carbon (SOC) and nutrients, e.g. nitrogen (N), affected by erosion. Herein, we report the outcomes of an experiment where a C-4 maize (Zea mays) crop (delta C-13 = -12.1 parts per thousand,) was cultivated and incorporated for 2 years to introduce a 'pulse' of C-13-enriched SOC to a C-3 arable soil (delta C-13 = -27.4 parts per thousand). Soils were sampled at eroding (top slope and upper slope) and depositional (lower slope and slope foot) positions of an accelerated erosion pathway that were confirmed using Cs-137 measurements. The sand particle-sized fraction (63-2000 mu m) was predominant and increased in the depositional slope positions due to selective loss of fine particles and preferential deposition of the coarsest fraction of transported sediment. There was a significant isometric relationship between the percentage SOC and total N: top slope > upper slope > lower slope, with similar values in the slope foot to the top slope. The delta N-15 values of the soils were enriched (7.3 parts per thousand) at the slope foot, compared with the other slope positions (average 6.3 parts per thousand), suggesting increased denitrification rates. The delta C-13 values of the soil microbial biomass C extracted from surface soils (0-5 cm) at each slope position showed that the proportion of maize C being incorporated into the soil microbial biomass declined in the downslope direction from 54% (top slope) to 43% (upper slope) to 18% (lower slope) in inverse proportion to the size of the soil microbial biomass, and increased to 41% at the slope foot. This suggests dynamic replacement of the SOC with crop C in the eroding slope positions and dilution of the transported C by C3-SOC in the depositional slope positions. This paper is evidence that erosional distribution of soil carbon leads to differential microbial utilisation of SOC between eroding and depositional sites. (C) 2013 Elsevier Ltd. All rights reserved.

KW - soil erosion

KW - agriculture

KW - soil microbial biomass

KW - carbon cycling

KW - nitrogen cycling

KW - landscape-scale variations

KW - N-15 natural-abundance

KW - tillage erosion

KW - climate-change

KW - matter

KW - biomass

KW - plant

KW - delta-C-13

KW - turnover

KW - dynamics

U2 - 10.1016/j.soilbio.2013.01.027

DO - 10.1016/j.soilbio.2013.01.027

M3 - Article

VL - 60

SP - 195

EP - 201

JO - Soil Biology and Biochemistry

JF - Soil Biology and Biochemistry

SN - 0038-0717

ER -