HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Sichani, S. A. Articles by Nelson, D.W. Search for Related Content PubMed Articles by Sichani, S. A. Articles by Nelson, D.W. Agricola Articles by Sichani, S. A. Articles by Nelson, D.W.

Relationship between Soluble and Extractable Phosphorus in Some Calcareous Soils of Iran

Irrigation Engineering Dep., Agric. College, Shiraz Univ., Shiraz, Iran;

D.W. Nelson

Agricultural Research Div., Univ. of Nebraska, Lincoln, NE, 68583-0704.

^* Corresponding author.

ABSTRACT

The relationship between water-extractable P (soluble P) and NaHCO₃-extractable P was determined in different water/soil ratios. The values of 0, 45, 90, and 180 mg kg^–1 soil as KH₂PO₄ were added to seven calcareous soil series from southern Iran (for two soil series additional P rates of 360, 720, and 1080 mg P kg^–1 soil as KH₂PO₄ also was employed). Soluble P in water/soil ratios of 10:1, 25:1, 100:1, and 500:1 was measured by Murphy and Riley method (1962) after 2 h shaking. Sodium bicarbonate—extractable P also was determined in all soils. The results indicate that there was a linear relationship between the logarithm of soluble and NaHCO₃-extractable P when NaHCO₃-extractable P was less than 150 mg P kg^–1 soil. There also was a linear relationship between soluble P and the water/soil ratio up to 100:1 for these soils. The amount of P released per unit soil weight at water/soil ratios greater than 100:1 was approximately constant.