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Updated: Jul 15, 2026
12:03
Two-Dimensional Visualization and Quantification of Labile, Inorganic Plant Nutrients and Contaminants in Soil
Published on: September 1, 2020
Solute transport and extraction by a single root in unsaturated soils: model development and experiment
Jaisoo Kim1, Kijune Sung, M Yavuz Corapcioglu
1Department of Civil Engineering, Texas A&M University, College Station, TX, USA.
Environmental Pollution (Barking, Essex : 1987)
|June 24, 2004
Summary
A new model simulates 2,4,6-trinitrotoluene (TNT) transport in soil using onion roots. Results show higher TNT concentrations in the rhizosphere than bulk soil due to root uptake dynamics.
Area of Science:
- Environmental Science
- Soil Science
- Bioremediation
Background:
- 2,4,6-trinitrotoluene (TNT) is a persistent organic pollutant.
- Understanding TNT fate and transport in soil is crucial for environmental remediation.
- Phytoremediation using plants offers a potential strategy for TNT-contaminated sites.
Purpose of the Study:
- To develop and validate a contaminant transport model for TNT.
- To investigate TNT uptake and accumulation in plants via a single-root system.
- To introduce new parameters for accurately modeling TNT root uptake.
Main Methods:
- A single-root system with onions was used to study 14C-TNT transport.
- Mass balance of TNT was monitored in soil, soil solution, roots, and leaves.
- A new root uptake rate (Rur) and transpiration stream concentration factor (TSCF) were developed and incorporated into the model.
Main Results:
- The model accurately simulated TNT concentrations in different plant compartments and soil zones.
- Higher TNT concentrations were observed in the rhizosphere compared to bulk soil.
- The new Rur and TSCF parameters improved the model's correlation with experimental TNT uptake data.
Conclusions:
- The developed model provides a robust tool for simulating TNT fate and transport.
- Root uptake significantly influences TNT distribution in the soil-plant system.
- The findings support the potential of phytoremediation for TNT-contaminated soils.
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