Assessment of water and sediment quality variation due to organic and conventionally irrigated pre-germinated rice-field cultivation

This study evaluated the water and sediment quality of samples collected from different points in organic (O1, O2, O3, O4) conventional (C1, C2, C3) pre-germinated rice fields located Viamão/RS. Quality indicators such as phosphorus, dissolved oxygen, manganese, iron, turbidity, BOD5 reduced beyond Classes 3 4, defined by CONAMA Resolution 357/2005. Based on aluminum levels, all were categorized Class 4; furthermore, IQA classified Points O4 C1 “bad.” The COD/BOD ratio was high, demonstrating that biodegradable fraction considerably low. conductivity at O4, C1, C3, exceeded 100 µS/cm, CETESB, indicating impacted environments. levels zinc nickel C3 reference values established FEPAM Ordinance 85/2014. In general, lowest observed O2 Point field.
 Keywords: coliforms, no 357/2005, 85/2014, irrigated rice, physicochemical analysis.