Fig. 1. Cumulative dissolved total P leached from manures and composts with time. Values are expressed as percentage of total water-extractable phosphorus (WEP). Data from Sharpley and Moyer (2000). (a) Comparison of first-order (dashed lines) and second-order (solid lines) kinetic models. (b) Comparison of power function (dashed lines) and Elovitch (solid lines) relationships.