Chemical Changes of Applied and Native Phosphorus During Incubation and Distribution into Different Soil Phosphorus Pools

作者：V.A. Ochwoh, Andries S. Claassens, P. C. de Jager · 发表于：Communications in Soil Science and Plant Analysis · 年份：2005 · DOI：10.1081/css-200043281 · 被引用次数：34 · 研究领域：Soil and Water Nutrient Dynamics、Phosphorus and nutrient management、Soil Carbon and Nitrogen Dynamics

The chemical transformations of applied and residual soil phosphorus (P) into different pools in two soils [Alfisols], a red sandy clay soil [Haplo‐Palcustalfs] from Rustenburg, which is a high P fixing, and a red sandy loam soil [Pale‐Xerults] from Loskop, a low P fixing were examined after treatments with different P rates (0, 25, 50, 100, 150, and 200 mg kg−1) and incubation periods (1, 60, 120, 180, and 240 days) under laboratory conditions. A sequential P extraction procedure was carried out on each treatment combination to determine the changes in 1) soluble and labile, 2) adsorbed, and 3) occluded and residual P pools in each soil. By fractionating soil P into different pools, it was possible to observe the transformation and distribution of added and initial soil P into different pools after each incubation period. Although solution and labile P decreased with time of incubation, there were corresponding increases in adsorbed, occluded, and residual P. Loskop soil had more marked increases in solution and labile P than the Rustenburg soil, which showed higher values for the adsorbed, occluded, and residual P forms. These differences could explain the reportedly higher levels of P fixation (adsorption and/or precipitation) by the Rustenburg than by the Loskop soil. Approximately 30–60% of the added P was transformed into less labile P pools in 1 day and 80–90% of the added P was transformed to the less labile P pools after 60 days of incubation. This transformation was...