TY  - JOUR
AU  - Mertens, J.
AU  - Vanderborght, J.
AU  - Kasteel, R.
AU  - Pütz, T.
AU  - Merckx, R.
AU  - Feyen, J.
AU  - Smolders, E.
TI  - Dissolved organic fluxes under bare soil
JO  - Journal of environmental quality
VL  - 36
SN  - 0047-2425
CY  - Madison, Wis.
PB  - ASA [u.a.]
M1  - PreJuSER-57155
SP  - 597 - 606
PY  - 2007
N1  - Record converted from VDB: 12.11.2012
AB  - The flux of dissolved organic carbon (DOC) in soil facilitates transport of nutrients and contaminants in soil. There is little information on DOC fluxes and the relationship between DOC concentration and water flux in agricultural soils. The DOC fluxes and concentrations were measured during 2.5 yr using 30 automatic equilibrium tension plate lysimeters (AETPLs) at 0.4 m and 30 AETPLs at 1.20-m depth in a bare luvisol, previously used as an arable soil. Average annual DOC fluxes of the 30 AETPLS were 4.9 g C m(-2) y(-1) at 0.4 m and 2.4 g C m(-2) y(-1) at 1.2 m depth. The average leachate DOC concentrations were 17 mg C L(-1) (0.4 m) and 9 mg C L(-1) (1.2 m). The DOC concentrations were unrelated to soil moisture content or average temperature and rarely dropped below 9 mg C L(-1) (0.4 m) and 5 mg C L(-1) (1.2 m). The variability in cumulative DOC fluxes among the plates was positively related to leachate volume and not to average DOC concentrations at both depths. This suggests that water fluxes are the main determinants of spatial variability in DOC fluxes. However, the largest DOC concentrations were inversely proportional to the mean water velocity between succeeding sampling periods, suggesting that the maximal net DOC mobilization rate in the topsoil is limited. Elevated DOC concentrations, up to 90 mg C L(-1), were only observed at low water velocities, reducing the risks of DOC-facilitated transport of contaminants to groundwater. The study emphasizes that water flux and velocity are important parameters for DOC fluxes and concentrations.
KW  - Bromides
KW  - Carbon: analysis
KW  - Soil: analysis
KW  - Water Movements
KW  - Bromides (NLM Chemicals)
KW  - Soil (NLM Chemicals)
KW  - Carbon (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:17332264
UR  - <Go to ISI:>//WOS:000244979300028
DO  - DOI:10.2134/jeq2006.0368
UR  - https://juser.fz-juelich.de/record/57155
ER  -