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Updated: Feb 10, 2026
10:05
Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation
Published on: July 4, 2014
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[Prediction of Cd in vegetables and soil Cd threshold derivation based on transfer function.]
Yang Yang1, Mei E Wang1, Yan Ling Li1
1State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Summary
This study analyzed cadmium (Cd) in soil and vegetables to understand uptake. Soil properties like pH and organic matter influence Cd accumulation, affecting safe vegetable cultivation limits.
Area of Science:
- Environmental Science
- Agricultural Science
- Soil Science
Background:
- Cadmium (Cd) accumulation in vegetables poses risks to human health.
- Understanding soil-vegetable transfer functions is crucial for risk management.
- China's foodstuff regulations require soil Cd thresholds for safe cultivation.
Purpose of the Study:
- To determine the influence of soil properties on Cd uptake by vegetables.
- To derive soil Cd thresholds for vegetable cultivation.
- To assess Cd accumulation potential in different vegetable types.
Main Methods:
- Analysis of 745 paired soil and vegetable samples.
- Application of species sensitivity distribution models.
- Stepwise multiple regression analysis to identify key soil factors.
Main Results:
- Leafy vegetables showed higher Cd accumulation potential than rootstalk vegetables.
- Soil total Cd, pH, and soil organic matter (SOM) significantly influenced Cd uptake.
- Transfer functions explained 54.2% (leafy) and 69.1% (rootstalk) of Cd accumulation variance.
- Soil Cd thresholds increase with soil pH and SOM.
Conclusions:
- Rootstalk vegetables may be hazardous in acidic soils.
- Current soil Cd limits might overestimate risks in acidic, low-SOM soils of Southern China.
- Soil properties are critical determinants of Cd transfer to vegetables, necessitating tailored risk assessments.
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