Abstract

Soil tests P (STP) developed to estimate P fertilizer needs and designed to produce optimal economic crop yields, are often not well suited to assess potential environmental impact of fertilization practices. The objective of this study was to develop interpretative soil groupings of the Montreal Lowlands area (MLA) based on soil physico-chemical properties and on soil P sorption and desorption characteristics. Soil P sorption and desorption characteristics together with STP may help in evaluating potential risks of soil P addition. Sixty-six soil types (phases of soil series based on surface texture) were selected as representative soils of the study area. Twenty-seven soil properties were used, including Mehlich-3 extractable P and Al, ammonium-oxalate extractable P, Fe and Al, P sorption index (Psi) and Bray-2 extractable P(BR2P). Multivariate analysis was applied to generate clusters and interpret soil groupings. Principal components analysis yielded two components related: (1) to soil inherent fertility (texture) and (2) to P sorption capacity and desorption intensity. The Ward's clustering method was then applied to the first two component scores. Five soil fertility groups were obtained. Multiple discriminant analysis proposed a classification model using a small subset of variables. Five variables were selected among the soil survey characteristics for discriminating soil groups: clay content, pH measurement in water, cation exchange capacity, BR2P and ammonium-acetate extractable Mg. Adding Psi in the model improved the classification correctness. The results of this study indicate that physico-chemical properties of the surface layer used together with soil P sorption-desorption characteristics contributed to the development of an interpretative grouping that may also be useful to assess vulnerability to water contamination by P. Key words: Soil behavior, soil fertility groups, multivariate analysis techniques

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.