Fig. 5. Relationship between (a) soil WSP, (b) soil WSP/100 g clay and runoff DRP for soils considered "high" (>0.5) and "low" (<0.5) in the ratio of HIV to kaolinite based on soil mineralogical analysis of the nine different soil types. For each figure, correlation lines of "high" and "low" HIV to kaolinite were significantly different from each other at P = 0.05.