About Us | Help Videos | Contact Us | Subscriptions

Soil Science Society of America Journal Abstract - DIVISION S-8—NUTRIENT MANAGEMENT & SOIL & PLANT ANALYSIS

Pathways of Soil Phosphorus Transformations after 8 Years of Cultivation under Contrasting Cropping Practices


This article in SSSAJ

  1. Vol. 66 No. 3, p. 999-1007
    Received: Mar 26, 2001

    * Corresponding author(s): Simardrr@umanitoba.ca
Request Permissions

  1. Zhiming Zhenga,
  2. Régis R. Simard *b,
  3. Jean Lafondc and
  4. Léon E. Parenta
  1. a Dep. of Soil and Agri-Food Engineering, Laval Univ., Ste-Foy, QC, Canada G1K 7P4
    b Dep. of Soil Science, Univ. of Manitoba, Winnipeg, MB, Canada R3T 2N2
    c Agriculture and Agri-Food Canada Research Farm, Normandin, QC, Canada G8M 4K3


The knowledge of P transformations is essential to understand the P behaviour in soils. Organic (Po) and inorganic (Pi) P fractions were obtained from the 0- to 30- and 30- to 90-cm layers of a Labarre silty clay (fine, mixed, frigid, Humic Cryaquept) by a sequential extraction. Barley (Hordeum vulgare L.) monoculture and 3-yr barley-forage rotation as main plots, and two nutrient sources (mineral fertilizer and liquid dairy manure) as subplots were studied. Path analysis was used to describe soil P transformations between the falls of 1989 and 1997. Nutrient source was the main factor affecting P transformations in the 0- to 30-cm soil layer, whereas crop rotation predominated in the subsoil. Pathways differed more for Po than for Pi pools. In the 0- to 30-cm soil layer, 86 to 97% of the variation in resin-P was the direct effect of added Pi The NaHCO3-Pi and Po were sensitive to crop rotations and nutrient sources, and were transitory pools of soil P. The NaOH-Pi was a sink for added Pi and a source of NaHCO3-Pi Labile Pi tended to store as NaOH-Po, which was the sink for added Po and immobilized soil Pi in the mineral fertilizer systems. Conversely, the NaOH-Po was mineralized and contributed to labile Pi in dairy manure systems. The NaOH-Po acted as store of subsoil Po in the monoculture but was the main source of labile P in the rotation systems. The P transformations in this Cryaquept were strongly influenced by nutrient sources and crop rotations.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2002. Soil Science SocietyPublished in Soil Sci. Soc. Am. J.66:999–1007.