Phosphorus Availability in Reddish Brown Lateritic Soils. II. Relationships Between Field, Greenhouse, and Soil Analyses¹

Abstract

Synopsis No method was found to be significantly superior to any other in predicting the P status of the soils. The Olsen method was least affected by soil pH and generally yielded the highest correlation coefficient. This will probably continue to be the method used by the Oregon State University Soil Testing Laboratory for both acid and calcareous soils.

Phosphorus Distribution in Five Highly Weathered Alabama Soils

“…Soil pH was measured in H 2 O using a combination electrode. [17] Soil P availability indices were determined according to the methods of Mehlich, [18] Olsen et al, [19] Bray and Kurtz, [20] Truog, [21] and Jackson et al [22] soil tests extractants. All the cations were determined using inductive couple plasma (ICP).…”

Phosphorus Availability in Reddish Brown Lateritic Soils. I. Laboratory Studies1

“…The procedure described by Jackson et a!. ( 5) was followed. Also the amount of inorganic phosphorus lost from the soil during the cropping period was studied.…”

“…This paper reports on some of the laboratory phases of the experiment which were designed to compare several phosphorus soil test methods and to learn more about the forms of inorganic phosphorus in these soils. A companion paper will report on relationships between three different phosphorus soil test methods and response from phosphorus under greenhouse and field conditions ( 5) .…”

Development of an alternative to the Olsen bicarbonate-extraction test for determining plant-available phosphorus in basaltic soils

“…5~ sodium bicarbonate, buffered at pH 8.5, with a soil to solution ratio of 1:20 v/v and an extraction time of 30min (Olsen et al 1954). Jackson-P was extracted by 0.5 M sodium bicarbonate buffered at pH 8.5 and 0.1 M ammonium fluoride, with a soil to solution ratio of 1:20 v/v and an extraction time of 30min (Jackson et al 1964). Morgan-P was extracted by 10% sodium acetate, buffered at pH 4.8 with a solution ratio of 1:s v/v and an extraction time of 30min (Morgan 1941).…”

“…The aim of this study was to find a soil test that would provide a reliable assessment of plant-available P in basaltic grassland soils in Northern Ireland. The methods investigated included the Jackson (Jackson et al 1964) and Morgan (Morgan 1941) tests, a CaClz extraction of P (Reddy et al. 1980), an anion exchange resin assessment of soil capacity to replenish solution P (Tiessen & Moir 1993), an ammonium oxalate extraction of P (McKeague & Day 1966), and a prediction of the degree of P saturation (DPS) based on ammonium oxalate extractable P, A1 and Fe (Maguire et al 2001).…”