Forms of Extractable Aluminium in Relation to Pedogenic Process in Two Inceptisols and an Alfisol of Orissa

摘要

In order in study the forms and pedogenic distribution of various forms of aluminium in two Inceptisols and an Alfisol under Mahanadi catchment area of Phulbani district of Orissa, soil samples were analyzed by selective extraction procedure. The meancontents of aluminium were extracted by various extracting reagents and were found to be in descending order as follows : Al_(dith)>Al_(oxa)>Al_(pyr)>Al_(EDTA)>Al_(HOAC)>Al(NH_4)_2SO_4>Al_(KCl . ) The soil series can be arranged, on the basis of the mean of aluminium extracted by KC1, (NH_4)_2SO_4, acetic acid , EDTA, pyrophosphate, oxalate and dithionite as Nuagaon >Tagania>Depakata. Moreover, analysis of pyrophosphate, oxalate, and dithionite extractable Al showed that with increasing age of soil, the crystalline aluminium oxide increases at the expense of the poorly crystalline form. This trend is reflected in the ratio of Al_(oxa)/Al_(dith) (Al ratio). The Al_(dith) values are higher than the Al_(oxa) values in the soils, indicating that a considerable fraction is present in crystalline form. The mean contents of crystalline Al and the Al_(oxa)/Al_(dith) ratio values estimated the degree of soil development and were found to be in descending order: Tagania>Nuagaon>Depakata. Correlation between different forms of aluminium and selected soil properties were examined.