Fractional Characteristics of Heavy Metals Pb, Zn, Cu, and Cd in Sewer Sediment from Areas in Central Beijing, China

Figure 3

The fractionation distribution of metals Cu, Zn, Cd, and Pb in six functional areas: (I) old residential area, (II) comprehensive area, (III) new residential area, (IV) pedestrian only commercial area, (V) educational area, and (VI) business area. Note: E, C, Fe-Mn, O, and R represent exchangeable fraction, carbonate bound fraction, Fe-Mn oxide bound fraction, organically bound fraction, and residual fraction, respectively.

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