Variability of copper availability in paddy fields in relation to selected soil properties in southeast China

摘要: Copper (Cu) is an essential nutrient element for plant growth and a toxic heavy metal in excess concentrations. As such, its concentration availability soils are of great agricultural environmental concern. Availability spatial pattern copper relation to selected soil properties surface were evaluated region southeastern China. A total 224 topsoil samples (0-15 cm) collected from paddy fields study area 731 km2. We measured Cu DTPA-extractable (available Cu) concentrations, pH, organic matter content (SOM), nitrogen, available phosphorus, potassium, cation exchange capacity (CEC). estimated by calculating the ratio concentration. The results our chemical analyses indicated that both concentrations had wide range throughout area. In addition, we slight accumulation comparison background levels at Zhejiang Province scale. Correlation analysis revealed was positively correlated with concentration, CEC SOM as moderate high correlation coefficients (r = 0.64-0.82), directly SOM, pH positive 0.47-0.82) 0.01 level significance. Spatial distribution maps illustrated similar trends highest northeast low southwest trend ratios central Soil influencing addition Cu.