Challenges in modelling dissolved organic matter dynamics in agricultural soil using DAISY
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Challenges in modelling dissolved organic matter dynamics in agricultural soil using DAISY. / Gjettermann, Birgitte; Styczen, Merete; Hansen, Hans Christian Bruun; Vinther, Finn Pilgaard; Hansen, Søren.
In: Soil Biology & Biochemistry, Vol. 40, No. 6, 2008, p. 1506-1518.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Challenges in modelling dissolved organic matter dynamics in agricultural soil using DAISY
AU - Gjettermann, Birgitte
AU - Styczen, Merete
AU - Hansen, Hans Christian Bruun
AU - Vinther, Finn Pilgaard
AU - Hansen, Søren
N1 - Special Section: Functional Microbial Ecology: Molecular Approaches to Microbial Ecology and Microbial Habitats, 18th World Congress of Soil Science
PY - 2008
Y1 - 2008
N2 - Because dissolved organic matter (DOM) plays an important role is terrestrial C-, N- and P-balances and transport of these three components to aquatic environments, there is a need to include it in models. This paper presents the concept of the newly developed DOM modules implemented in the DAISY model with focus on the quantification of DOM sorption/desorption and microbial-driven DOM turnover. The kinetics of DOM sorption/desorption is described by the deviation of the actual DOM concentration in solution from the equilibrium concentration, Ceq. The Ceq is soil specific and estimated from pedotransfer functions taking into account the soil content of organic matter, Al and Fe oxides. The turnover of several organic matter pools including one DOM pool are described by first-order kinetics.The DOM module was tested at field scale for three soil treatments applied after cultivating grass-clover swards. Suction cups were installed at depths 30, 60 and 90 cm and soil solution was sampled for quantification of dissolved organic C (DOC) and dissolved organic N (DON). In the topsoil, the observed fluctuations in DOC were successfully simulated when the sorption/desorption rate coefficient k was low. In the subsoil, the observed concentrations of DOC were steadier and the best simulations were obtained using a high k. The model shows that DOC and DON concentrations are levelled out in the subsoils due to soil buffering. The steady concentration levels were based on the Ceq for each horizon and the kinetic concept for sorption/desorption of DOC appeared a viable approach. If Ceq was successfully estimated by the pedotransfer function it was possible to simulate the DOC concentration in the subsoil. In spite of difficulties in describing the DOC dynamics of the topsoil, the DOM module simulates the subsoil concentration level of DOC well, and also-but with more uncertainty-the DON concentration level.
AB - Because dissolved organic matter (DOM) plays an important role is terrestrial C-, N- and P-balances and transport of these three components to aquatic environments, there is a need to include it in models. This paper presents the concept of the newly developed DOM modules implemented in the DAISY model with focus on the quantification of DOM sorption/desorption and microbial-driven DOM turnover. The kinetics of DOM sorption/desorption is described by the deviation of the actual DOM concentration in solution from the equilibrium concentration, Ceq. The Ceq is soil specific and estimated from pedotransfer functions taking into account the soil content of organic matter, Al and Fe oxides. The turnover of several organic matter pools including one DOM pool are described by first-order kinetics.The DOM module was tested at field scale for three soil treatments applied after cultivating grass-clover swards. Suction cups were installed at depths 30, 60 and 90 cm and soil solution was sampled for quantification of dissolved organic C (DOC) and dissolved organic N (DON). In the topsoil, the observed fluctuations in DOC were successfully simulated when the sorption/desorption rate coefficient k was low. In the subsoil, the observed concentrations of DOC were steadier and the best simulations were obtained using a high k. The model shows that DOC and DON concentrations are levelled out in the subsoils due to soil buffering. The steady concentration levels were based on the Ceq for each horizon and the kinetic concept for sorption/desorption of DOC appeared a viable approach. If Ceq was successfully estimated by the pedotransfer function it was possible to simulate the DOC concentration in the subsoil. In spite of difficulties in describing the DOC dynamics of the topsoil, the DOM module simulates the subsoil concentration level of DOC well, and also-but with more uncertainty-the DON concentration level.
KW - Former LIFE faculty
KW - Dissolved organic matter;
KW - Dissolved organic C
KW - Dissolved organic N
KW - Initial mass isotherm
KW - Sorption kinetics
KW - Organic Matter
KW - Modelling DOM dynamics
KW - Leaching
U2 - 10.1016/j.soilbio.2008.01.005
DO - 10.1016/j.soilbio.2008.01.005
M3 - Journal article
VL - 40
SP - 1506
EP - 1518
JO - Soil Biology & Biochemistry
JF - Soil Biology & Biochemistry
SN - 0038-0717
IS - 6
ER -
ID: 8108213