Influence of composting on the manure Cu and Zn speciation in two soils

摘要

Owing to the Cu and Zn supplements are commonly oversupplied in the animal feeding stuffs, their residues in the manure might pose potential risks on environment and food chain when the manure are used in farmland. Composting is an effective way to treat animal manure, and might cause the metal speciation less available. The objective of this study is to determine the effects of composting on the speciation redistribution of manure Cu and Zn when the manure is applied in the different soils. The results showed that composting could decrease significantly their availability. Moreover, the soil with high OM (organic matter) may accumulate more unavailable Cu than the sterile soil. It suggested that the bioavailability of metals cannot be solely determined by the characteristics of the manure, but consideration of soil properties is also required.