Determination of the Phosphorus Fixation of the Wheat-Growing Soils in the Lake Van Basin

Abstract

The aim of this study was to assess phosphorus fixation and impinging factors on wheat cultivated fields around the Lake Van region. Main soil groups were taken into account according to their folding areas representing the province, namely Calcisol Cambisol, Kastanozem, Fluvisol and Regosol, in two levels of depth, 0-20 cm and 20-40 cm. A total of 52 soil samples were taken from different areas. Phosphorus fixation capacity was calculated by adding three level of phosphorus, 25 ppm, 50 ppm, 150 ppm; half an hour, twenty-four hours and seventy two hours. Phosphorus fixations were found to be 51.2% in Calcisols, 45.2% in Cambisols, 50.8% in Kastanozems, 47.8% in Fluvisols and 45.1% in Regosol groups. It was also recorded that the big proportion of phosphorus fixations at all soil group occurred in half an hour's time. There were significant correlations between characteristics of soil groups and phosphorus fixation. These correlations with phosphorus fixation, within Calcisol soils, CEC and organic matter, within Cambisols, clay, silt, sand, organic matter and CEC, within Fluvisols, clay, sand, CaCO3 and pH, within regosols, clay and CaCO and pH were detected positively. However, within Cambisol and Fluvisol, negative correlations between phosphorus fixation and sand were detected. © 2006 Asian Network for Scientific Information.