Details
| Original language | English |
|---|---|
| Pages (from-to) | 8-16 |
| Number of pages | 9 |
| Journal | Agriculture, Ecosystems and Environment |
| Volume | 129 |
| Issue number | 1-3 |
| Publication status | Published - Jan 2009 |
Abstract
Heavy metal (HM) contaminations in the topsoil around handicraft villages with non-ferrous heavy metal recycling in the Red River Delta can impose serious threats to the subsoil as well as to the groundwater quality. This feature is very important for paddy soils due to relatively high leaching rates and the dissolution of Fe-Mn oxides under reducing conditions which can accelerate the amount of HM translocated to the subsoil and groundwater. The transport of Cu, Pb and Zn in paddy soils was simulated by numerical modeling of non-equilibrium solute transport with an adaptation of the Hydrus-1D model. For the simulation, a water layer on the soil surface was included, from which HM can infiltrate into the soil depending on the soil hydraulic properties. Sorption coefficients, obtained from batch experiments were used as input data for the simulations. Calculated leaching rates were compared with the binding forms of HM in the samples. The simulations show that leaching rates decrease in the order: Zn > Cu > Pb. This order is confirmed by the results of sequential extractions. Under constant flooded conditions at a water table of 20 cm, Cu, Pb and Zn were estimated to reach the soil depth of 1 m within 470, 495 and 370 days, respectively, emphasizing that reactive pollutants can reach groundwater in a relatively short time. A change of the water layer from 1 to 30 cm can accelerate the leaching rate of HM up to 36%. The hard pan layer was observed to induce a hysteresis in hydraulic conductivity and slow down the movement of HM. Uncertainties in modeling arise as several parameters in the simulation can be determined only with significant errors. However, Hydrus-1D is a suitable tool for simulation of the transport of HM in paddy soils.
Keywords
- Heavy metal, Modeling, Paddy soil, Solute transport, Sorption kinetics
ASJC Scopus subject areas
- Environmental Science(all)
- Ecology
- Agricultural and Biological Sciences(all)
- Animal Science and Zoology
- Agricultural and Biological Sciences(all)
- Agronomy and Crop Science
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Agriculture, Ecosystems and Environment, Vol. 129, No. 1-3, 01.2009, p. 8-16.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Simulation of retention and transport of copper, lead and zinc in a paddy soil of the Red River Delta, Vietnam
AU - Nguyen Ngoc, Minh
AU - Dultz, Stefan
AU - Kasbohm, Jörn
N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2009/1
Y1 - 2009/1
N2 - Heavy metal (HM) contaminations in the topsoil around handicraft villages with non-ferrous heavy metal recycling in the Red River Delta can impose serious threats to the subsoil as well as to the groundwater quality. This feature is very important for paddy soils due to relatively high leaching rates and the dissolution of Fe-Mn oxides under reducing conditions which can accelerate the amount of HM translocated to the subsoil and groundwater. The transport of Cu, Pb and Zn in paddy soils was simulated by numerical modeling of non-equilibrium solute transport with an adaptation of the Hydrus-1D model. For the simulation, a water layer on the soil surface was included, from which HM can infiltrate into the soil depending on the soil hydraulic properties. Sorption coefficients, obtained from batch experiments were used as input data for the simulations. Calculated leaching rates were compared with the binding forms of HM in the samples. The simulations show that leaching rates decrease in the order: Zn > Cu > Pb. This order is confirmed by the results of sequential extractions. Under constant flooded conditions at a water table of 20 cm, Cu, Pb and Zn were estimated to reach the soil depth of 1 m within 470, 495 and 370 days, respectively, emphasizing that reactive pollutants can reach groundwater in a relatively short time. A change of the water layer from 1 to 30 cm can accelerate the leaching rate of HM up to 36%. The hard pan layer was observed to induce a hysteresis in hydraulic conductivity and slow down the movement of HM. Uncertainties in modeling arise as several parameters in the simulation can be determined only with significant errors. However, Hydrus-1D is a suitable tool for simulation of the transport of HM in paddy soils.
AB - Heavy metal (HM) contaminations in the topsoil around handicraft villages with non-ferrous heavy metal recycling in the Red River Delta can impose serious threats to the subsoil as well as to the groundwater quality. This feature is very important for paddy soils due to relatively high leaching rates and the dissolution of Fe-Mn oxides under reducing conditions which can accelerate the amount of HM translocated to the subsoil and groundwater. The transport of Cu, Pb and Zn in paddy soils was simulated by numerical modeling of non-equilibrium solute transport with an adaptation of the Hydrus-1D model. For the simulation, a water layer on the soil surface was included, from which HM can infiltrate into the soil depending on the soil hydraulic properties. Sorption coefficients, obtained from batch experiments were used as input data for the simulations. Calculated leaching rates were compared with the binding forms of HM in the samples. The simulations show that leaching rates decrease in the order: Zn > Cu > Pb. This order is confirmed by the results of sequential extractions. Under constant flooded conditions at a water table of 20 cm, Cu, Pb and Zn were estimated to reach the soil depth of 1 m within 470, 495 and 370 days, respectively, emphasizing that reactive pollutants can reach groundwater in a relatively short time. A change of the water layer from 1 to 30 cm can accelerate the leaching rate of HM up to 36%. The hard pan layer was observed to induce a hysteresis in hydraulic conductivity and slow down the movement of HM. Uncertainties in modeling arise as several parameters in the simulation can be determined only with significant errors. However, Hydrus-1D is a suitable tool for simulation of the transport of HM in paddy soils.
KW - Heavy metal
KW - Modeling
KW - Paddy soil
KW - Solute transport
KW - Sorption kinetics
UR - http://www.scopus.com/inward/record.url?scp=56449117055&partnerID=8YFLogxK
U2 - 10.1016/j.agee.2008.06.008
DO - 10.1016/j.agee.2008.06.008
M3 - Article
AN - SCOPUS:56449117055
VL - 129
SP - 8
EP - 16
JO - Agriculture, Ecosystems and Environment
JF - Agriculture, Ecosystems and Environment
SN - 0167-8809
IS - 1-3
ER -