9I4c P buffer index – PBIunadj – Vanadate

This method is identical to Method 9I2c and Method 9I3c, except that Colwell-P and Olsen-P values, respectively, are not included in the calculation of PBI. The relevant equation is shown in Method 9I4a, Note 1, Table 9.9.

Report unadjusted PBI on an air-dry (40°C) basis.