Relationship between some soil characteristics and contribution on available phosphorus of inorganic phosphorus fractions in calcareous soils

Abstract

Aims: The aim of this study is to determine the amount and distribution of inorganic phosphorus fractions in soil profiles classified as Mollisol and Entisol, which are common in the Eastern Anatolian region, and to determine their soil properties and their relationships with each other, and to evaluate the contribution of inorganic phosphorus fractions to available soil phosphorus (Olsen-P).Methods and Results: The total amount of phosphorus in these soils with calcareous and slightly alkaline reactions has been determined as 280-1713 mg kg-1 and an average of 713 mg kg-1. Ca-P’, which make up an average of 80.9% of the total phosphorus and which are determined as the first phosphorus fraction in these soils, have been determined between 163.2-951.1 mg kg-1. The occluded phosphates (CDB-P), which rank second in quantity in these soils after Ca-P2, are between 2.07-105.6 mg kg-1, and thirdly, phosphates (CB-P) held by carbonates during the first extraction are 0.76-52.83 mg kg-1. In the fourth and last row, nonoccluded aluminum and iron phosphates (Al-P + Fe-P) were found as the least amount of phosphorus fractions in these soils between 0.09-5.0 mg kg-1.Conclusions: In summary, the order of inorganic phosphorus fractions in these soils was determined as Ca-P> CDB-P> CB-P> Al-P+Fe-P. Significance and Impact of the Study: It was determined that two fractions contribute to phosphorus (Olsen-P), nonoccluded aluminum and iron phosphates (AI-P + Fe-P) and occluded phosphates (CDB-P) in these soils.