Systematic approach to source-sink apportionment of copper in paddy fields: Experimental observation, dynamic modeling and prevention strategy

• Published in: Journal of hazardous materials Vol. 417; p. 126045
• Main Authors: Tseng, Yi-Ho, Pan, Shu-Yuan, Syu, Wei-Jhan, Huang, Hung-Pin, Wei, Chao-Yu, He, Kung-Hui
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 05.09.2021
• Subjects: Climate change; Comprehensive dynamic models; Heavy metal; Water-saving management; Year of excess; Climate change; Year of excess; Water-saving management; Comprehensive dynamic models; Heavy metal
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.126045

The accumulation of heavy metals in paddy rice severely impacts the health of consumers and plants. In this study, a systematic approach to source-sink apportionment of copper in paddy fields was developed by considering all bioenvironmental interfaces. Experimental data from two experimental fields (namely Field A and Field B) in the first harvest period was collected. Then, mass-balance-based models with dynamic critical loads were established to evaluate the year of excess for copper. The results indicated that irrigation water contributed the highest portion (96.2–98.8%) of total copper inputs. Under the business-as-usual scenario, the soil copper concentration of Field A and Field B might exceed the Taiwanese national standard within 66 and 24 years, respectively. In addition, alternate wet-dry irrigation was found to be one of the total solutions to reducing copper accumulation in soils by 17–48%. It could also provide a significant reduction of water usage in paddy fields by ~25%, thereby increasing the resilience to extreme climate change events. Lastly, based on the field observations, three improvement strategies on sustaining soil quality towards better agricultural environment were proposed. The connection of copper accumulation in soils with dietary and ecological risks was also briefly illustrated. [Display omitted] •Source-sink apportionment and excess year for Cu in paddy fields were evaluated.•Total Cu inputs in two fields were about 143.0–364.4 mg/m2 per paddy rice harvest.•Irrigation water contributed around 96.2–98.8% of total Cu inputs in two fields.•Soil Cu in the business-as-usual Scenario may exceed the standard within 24 years.•Alternate wet-dry irrigation can reduce FIR by ~25% and extend Te by 17–48%.