Refining Soil Organic Matter Determination by Loss-on-Ignition

作     者：M.H.SALEHI O.HASHEMI BENI H.BEIGI HARCHEGANI I.ESFANDIARPOUR BORUJENI H.R.MOTAGHIAN 

作者机构：Department of Soil ScienceCollege of AgricultureShahrekord University Department of Soil ScienceCollege of AgricultureVali-e-Asr University 

出 版 物：《Pedosphere》 (土壤圈（英文版）)

年 卷 期：2011年第21卷第4期

页      面：473-482页

核心收录：

学科分类：09[农学] 0903[农学-农业资源与环境] 090301[农学-土壤学] 

基　　金：Supported by Shahrekord University Iran 

主　　题：calcium carbonate equivalent ignition temperature kriged maps spatial variability wet oxidation 

摘      要：Wet oxidation procedure,i.e.,Walkley-Black (WB) method,is a routine,relatively accurate,and popular method for the determination of soil organic matter (SOM) but it is time-consuming,costly and also has a high potential to cause environmental pollution because of disposal of chromium and strong acids used in this ***,loss-on-ignition (LOI) procedure,a simple and cheap method for SOM estimation,which also avoids chromic acid wastes,deserves more *** aims of this research were to study the statistical relationships between SOM determined with the LOI (SOMLOI) and WB (SOMWB) methods to compare the spatial variability of SOM in two major plains,Shahrekord and Koohrang plains,of Chaharmahal-va-Bakhtiari Province,*** surface soil samples (0-25 cm) were randomly collected in each plain to determine SOM using the WB method and the LOI procedure at 300,360,400,500 and 550 ℃ for 2 *** samples covered wide ranges of soil texture and calcium carbonate equivalent (CCE).The general linear form of the regression equation was calculated to estimate SOM LOI from SOM obtained by the WB method for both overall samples and individual *** soil samples were also randomly selected to compare the SOM and CCE before and after ignition at each *** accuracy of the continuous maps generated for the LOI and WB methods was considered to determine the accordance of two *** showed a significant positive linear relationship between SOM LOI and SOM *** of determination (R2) of the equations for individual plains were higher than that of the overall *** of determination and line slopes decreased and root mean square error (RMSE) increased with increasing ignition temperature,which may be due to the mineral structural water loss and destruction of carbonates at higher temperatures.A temperature around 360 ℃ was identified as optimum as it burnt most organic carbon,destroyed less inorganic carbon,cau