Volume 12, Number 44 (summer 2008)                   JWSS 2008, 12(44): 153-168 | Back to browse issues page

XML Persian Abstract Print

Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Jafari A, Shariatmadari H, Khademi H, Rezainejad Y. Soil Clay Mineralogy in Four Toposequences from Arid and Semiarid Regions and Its Relationship with Kinetics of Phosphorus Release. JWSS. 2008; 12 (44) :153-168
URL: http://jstnar.iut.ac.ir/article-1-876-en.html

Abstract:   (28543 Views)
Mineralogy is one of the most influential soil properties that change from upper- to lower slope positions, depending on the climate differences. Such changes affect soil properties such as phosphorus sorption and desorption processes differently. Therefore, this study was carried out to investigate the clay mineralogy of soils in four toposequences from arid (Isfahan) and semiarid (Chaharmahal Bakhtiari) regions and its effect on soil P release. The soils of three points on each toposequence were sampled as the upper-slope mainly containing parent materials the mid-slope, non-arable lands and the lower-slope, arable lands. Some of soil properties such as clay minerals were determined. Also, trend of P release parameters was studied in four toposequences. Results showed that the amount of clay, cation exchange capacity (CEC), electrical conductivity (EC), and pH of the soils increase down the slope in all toposequences. X-ray diffractograms showed that kaolinite and illite in upper slope and smectite and chlorite in lower slope were the predominant clays. Among the kinetic models examined based on their determination coefficient and standard error, the Elovich equation was chosen to describe the P release kinetics in studied soils. The trend of P desorption rate along the arid toposequences was in the following order: upper-slope < mid-slope < lower-slope. Furthermore, the rate of P desorption in soils of the semiarid toposequences was higher than arid toposequences. Regarding the trend of P rate parameters along the toposequences, it could be concluded that P release rate and the soil capacity to supply P for plants increase toward lower slope.
Full-Text [PDF 417 kb]   (2253 Downloads)    
Type of Study: Research | Subject: Ggeneral
Received: 2009/02/24

Add your comments about this article : Your username or email:
Write the security code in the box

© 2015 All Rights Reserved | JWSS - Isfahan University of Technology

Designed & Developed by : Yektaweb