Erosion of upland hillslope soil organic carbon: Coupling field measurements with a sediment transport model

Kyungsoo Yoo, Ronald Amundson, Arjun M. Heimsath, William E. Dietrich

Research output: Contribution to journalArticle

87 Citations (Scopus)

Abstract

Little is known about the role of vegetated hillslope sediment transport in the soil C cycle and soil-atmosphere C exchange. We combined a hillslope sediment transport model with empirical soil C measurements to quantify the erosion and temporal storage of soil organic carbon (SOC) within two grasslands in central California. The sites have contrasting erosional mechanisms: biological perturbation (Tennessee Valley (TV)) versus clay-rich soil creep (Black Diamond (BD)). The average SOC erosion rates from convex slopes were 1.4-2.7 g C m-2 yr-1 at TV and 5-8 g C m-2 yr-1 at BD, values that are <10% of above ground net primary productivity (ANPP) at both sites. The eroded soil accumulates on depositional slopes. The long term SOC accumulation (or C sink) rates are ∼1.9 g C m-2 yr-1 in the TV hollow and 1.7-2.8 g C m-2 yr-1 in the BD footslope. We found that the hillslope C sink is driven primarily by the burial of in situ plant production rather than preservation of eroded SOC, a finding that differs from existing hypotheses. At TV, the net sequestration of atmospheric C by long-term hollow evacuation and refilling depends on the fate of the C exported from the zero order watershed. This study suggests that erosion and deposition are coupled processes that create a previously unrecognized C sink in undisturbed upland watersheds, with a potential to substantially affect the global C balance presently, and over geological timescales.

Original languageEnglish (US)
Article numberGB3003
Pages (from-to)1-17
Number of pages17
JournalGlobal Biogeochemical Cycles
Volume19
Issue number3
DOIs
StatePublished - Sep 1 2005

Fingerprint

Sediment transport
Organic carbon
hillslope
sediment transport
Erosion
organic carbon
erosion
Soils
soil
diamond
valley
Watersheds
watershed
Earth atmosphere
erosion rate
clay soil
creep
grassland
perturbation
Creep

Cite this

Erosion of upland hillslope soil organic carbon : Coupling field measurements with a sediment transport model. / Yoo, Kyungsoo; Amundson, Ronald; Heimsath, Arjun M.; Dietrich, William E.

In: Global Biogeochemical Cycles, Vol. 19, No. 3, GB3003, 01.09.2005, p. 1-17.

Research output: Contribution to journalArticle

Yoo, Kyungsoo ; Amundson, Ronald ; Heimsath, Arjun M. ; Dietrich, William E. / Erosion of upland hillslope soil organic carbon : Coupling field measurements with a sediment transport model. In: Global Biogeochemical Cycles. 2005 ; Vol. 19, No. 3. pp. 1-17.
@article{27d80d71b6cc46e99f404f492792d679,
title = "Erosion of upland hillslope soil organic carbon: Coupling field measurements with a sediment transport model",
abstract = "Little is known about the role of vegetated hillslope sediment transport in the soil C cycle and soil-atmosphere C exchange. We combined a hillslope sediment transport model with empirical soil C measurements to quantify the erosion and temporal storage of soil organic carbon (SOC) within two grasslands in central California. The sites have contrasting erosional mechanisms: biological perturbation (Tennessee Valley (TV)) versus clay-rich soil creep (Black Diamond (BD)). The average SOC erosion rates from convex slopes were 1.4-2.7 g C m-2 yr-1 at TV and 5-8 g C m-2 yr-1 at BD, values that are <10{\%} of above ground net primary productivity (ANPP) at both sites. The eroded soil accumulates on depositional slopes. The long term SOC accumulation (or C sink) rates are ∼1.9 g C m-2 yr-1 in the TV hollow and 1.7-2.8 g C m-2 yr-1 in the BD footslope. We found that the hillslope C sink is driven primarily by the burial of in situ plant production rather than preservation of eroded SOC, a finding that differs from existing hypotheses. At TV, the net sequestration of atmospheric C by long-term hollow evacuation and refilling depends on the fate of the C exported from the zero order watershed. This study suggests that erosion and deposition are coupled processes that create a previously unrecognized C sink in undisturbed upland watersheds, with a potential to substantially affect the global C balance presently, and over geological timescales.",
author = "Kyungsoo Yoo and Ronald Amundson and Heimsath, {Arjun M.} and Dietrich, {William E.}",
year = "2005",
month = "9",
day = "1",
doi = "10.1029/2004GB002271",
language = "English (US)",
volume = "19",
pages = "1--17",
journal = "Global Biogeochemical Cycles",
issn = "0886-6236",
publisher = "American Geophysical Union",
number = "3",

}

TY - JOUR

T1 - Erosion of upland hillslope soil organic carbon

T2 - Coupling field measurements with a sediment transport model

AU - Yoo, Kyungsoo

AU - Amundson, Ronald

AU - Heimsath, Arjun M.

AU - Dietrich, William E.

PY - 2005/9/1

Y1 - 2005/9/1

N2 - Little is known about the role of vegetated hillslope sediment transport in the soil C cycle and soil-atmosphere C exchange. We combined a hillslope sediment transport model with empirical soil C measurements to quantify the erosion and temporal storage of soil organic carbon (SOC) within two grasslands in central California. The sites have contrasting erosional mechanisms: biological perturbation (Tennessee Valley (TV)) versus clay-rich soil creep (Black Diamond (BD)). The average SOC erosion rates from convex slopes were 1.4-2.7 g C m-2 yr-1 at TV and 5-8 g C m-2 yr-1 at BD, values that are <10% of above ground net primary productivity (ANPP) at both sites. The eroded soil accumulates on depositional slopes. The long term SOC accumulation (or C sink) rates are ∼1.9 g C m-2 yr-1 in the TV hollow and 1.7-2.8 g C m-2 yr-1 in the BD footslope. We found that the hillslope C sink is driven primarily by the burial of in situ plant production rather than preservation of eroded SOC, a finding that differs from existing hypotheses. At TV, the net sequestration of atmospheric C by long-term hollow evacuation and refilling depends on the fate of the C exported from the zero order watershed. This study suggests that erosion and deposition are coupled processes that create a previously unrecognized C sink in undisturbed upland watersheds, with a potential to substantially affect the global C balance presently, and over geological timescales.

AB - Little is known about the role of vegetated hillslope sediment transport in the soil C cycle and soil-atmosphere C exchange. We combined a hillslope sediment transport model with empirical soil C measurements to quantify the erosion and temporal storage of soil organic carbon (SOC) within two grasslands in central California. The sites have contrasting erosional mechanisms: biological perturbation (Tennessee Valley (TV)) versus clay-rich soil creep (Black Diamond (BD)). The average SOC erosion rates from convex slopes were 1.4-2.7 g C m-2 yr-1 at TV and 5-8 g C m-2 yr-1 at BD, values that are <10% of above ground net primary productivity (ANPP) at both sites. The eroded soil accumulates on depositional slopes. The long term SOC accumulation (or C sink) rates are ∼1.9 g C m-2 yr-1 in the TV hollow and 1.7-2.8 g C m-2 yr-1 in the BD footslope. We found that the hillslope C sink is driven primarily by the burial of in situ plant production rather than preservation of eroded SOC, a finding that differs from existing hypotheses. At TV, the net sequestration of atmospheric C by long-term hollow evacuation and refilling depends on the fate of the C exported from the zero order watershed. This study suggests that erosion and deposition are coupled processes that create a previously unrecognized C sink in undisturbed upland watersheds, with a potential to substantially affect the global C balance presently, and over geological timescales.

UR - http://www.scopus.com/inward/record.url?scp=27744550293&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=27744550293&partnerID=8YFLogxK

U2 - 10.1029/2004GB002271

DO - 10.1029/2004GB002271

M3 - Article

AN - SCOPUS:27744550293

VL - 19

SP - 1

EP - 17

JO - Global Biogeochemical Cycles

JF - Global Biogeochemical Cycles

SN - 0886-6236

IS - 3

M1 - GB3003

ER -