Đánh giá hiện trạng và hàm lượng selen trong đất nông nghiệp tại thành phố Long Khánh, tỉnh Đồng Nai

Abstract

The study was conducted to evaluate the physical and chemical properties, selenium and certain heavy metals content in agricultural soil. Soil parameters were analyzed using widely accepted methods and compared with Vietnamese standards and those established by the World Health Organization WHO, 2009. The research results indicated that the soil at the study site was highly acidic, with pH_H2O at 4.60±0.58 and pH_KCl at 4.35±0.86. Other parameters included: P₂O_5(dt) at 12.07±5.49 mg/kg, available potassium K₂O_(dt) at 14.84±4.95 mg/kg, organic carbon (OC) at 2.45±0.69%, total nitrogen N_(ts) at 0.13±0.02%, total phosphorus P₂O_5(ts) at 12.07±5.49 mg/kg, and total potassium K₂O_(ts) at 0.17±0.05 mg/kg. The average selenium content was 1.04±0.23 mg/kg dry soil, which is lower than the WHO guidelines, 2009. Therefore, it is necessary to implement measures to supplement selenium to ensure that crops receive adequate nutrients. At the time of the study, the soil showed no contamination with heavy metals such as copper (Cu, As, Pb, Cd, Hg) and zinc (Zn). However, the Cr and Ni content was measured at 273,17and 196,90mg/kg dry soil. This level exceeds the thresholds established in QCVN 03: 2015/BTNMT, indicating significant contamination with Cr and Ni, necessitating appropriate remediation strategies.