Fig. 3. Relationship between dissolved inorganic P concentrations in runoff from soil boxes and field plots where manures had been surface-applied and subjected to simulated rain. Data are as measured by Haggard et al. (2003), Kleinman et al. (2004), and Smith et al. (2004), and as predicted by Eq. [3] and [4], using either (a) measured runoff to rain ratios or (b) calculated P distribution fractions to distribute P released from manure into runoff or infiltrating water. The symbol *** designates significance at the 0.001 probability level.