Differential release of manure-borne bioactive phosphorus forms to runoff and leachate under simulated rain.

摘要: Abstract Limited information exists on the unhindered release of bioactive phosphorus (P) from a manure layer to model partitioning and transport component P forms before they reach an underlying soil. Rain simulations were conducted quantify effects intensity (30, 60, 90 mm h −1 ) application 60 Mg ha dairy manure. Runoff contained water-extractable- (WEP), exchangeable enzyme-labile (TBIOP), in contrast operationally defined “dissolved-reactive P” form. The released concentrations flow-weighed mass loads described by log-normal probability density function. At reference condition 30 mm h maintaining surface at 5% incline, runoff was minimal, WEP accounted for 20.9% leached total (TP) concentrations, with additional 25–30% as over 1-h simulation. On 20% increased accelerated occurrence concentration max shifted skewed distribution more left. Differences trends WEP, TBIOP, or net (PHP o cumulative per unit between intensities attributable higher frequency raindrops striking layer, thus increasing detachment load colloidal PHP water phases. Thus, detailed knowledge physical characteristics, relation rain intensity, attainment steady-state fluxes critical factors improved prediction movement manure-borne under rainfall.