The study looked at how different types of soil and the amount of heavy metals added affect where those metals end up in the soil. They found that the type of soil and the amount of metals added both play a role in where the metals end up. In red soil, lead and copper were mostly found in certain fractions, while zinc and cadmium were more spread out. In brown soil, lead and copper were found in more fractions, while zinc and cadmium were mostly in one fraction. The amount of metals added affected how easily they could be taken up by plants in red soil, but not as much in brown soil. The type of solution used to extract the metals also made a difference between the two soil types.