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Procedural effects on NaHC03 extractable soil P

Westermann, D.T. and Ehlers, R.S. (1986) Procedural effects on NaHC03 extractable soil P. pp. 63-69. In: Proc. 37th Annual Fertilizer Conf. USA-ID-Boise, 1986/07/08-09.

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Fertilization practices for optimum crop production will partially depend
upon reliable and accurate soil test results. A number of sail test procedures
have been developed and calibrated for most plant nutrients. Among them is the
NaHCO3 procedure for estimating plant available soil P. This procedure was
first published by Olsen and coworkers in 1954, and is widely accepted and used
in the U.S. and other countries, especially for neutral and calcareous soils.

An effort to standardize soil testing procedures and reporting units was
initiated by a Soil and Plant Testing Workgroup, sponsored by the PNWPF Association,
in 1968 with a sample exchange program (James, 1986). There has been a significant
improvement in reported soil test results among the active laboratories since
this project was started. No attempt is being made by this Workgroup to
standardize the recommendations made by the individual laboratories.

Significant sources of variability in reported soil test results could
include (a) sampling problems, both in the field and in the laboratory, (b)
different sample preparation methods, (c) laboratory errors, (d) individual
laboratory modifications of specific methods, and (e) the natural population
variance. The objective of this report is to evaluate the effect of selected
procedural modifications on NaHCO3 extractable soil P. The modifications were
in (1) extracting conditions, (2) NaHCO3 solution characteristics, and (3)
calorimetric procedure.

Item Type: Conference or Workshop Item (Paper)
NWISRL Publication Number: 0629
Subjects: Soil > Chemistry > Phosphorous
Mass Import - autoclassified (may be erroneous)
Depositing User: Dan Stieneke
Date Deposited: 20 Nov 2010 21:57
Last Modified: 10 Jan 2017 23:04
Item ID: 1044