The researchers studied how different chemicals affect the absorption of copper in different types of soil. They found that low levels of K2SO4 helped copper absorption in meadow cinnamon soil, while higher levels of KH2PO4 promoted absorption. The amount of copper absorbed in red soil changed with the concentration of the chemicals. In meadow cinnamon soil, copper absorption slightly increased and decreased with K2SO4 and KH2PO4, respectively. In red soil, lower levels of K2SO4 increased copper absorption, while KH2PO4 had a stronger effect. This research can help control copper pollution in soil.