Effects of Direct Land Application of Calcitic Lime and Lime- And Cement Kiln Dust-Sanitized Biosolids on the Chemical and Spectroscopic Characteristics of Soil Lipids

To determine the extent to which applications of calcitic lime and sanitized biosolids affect the quality of soil organic matter (SOM), lipids extracted from an unamended soil (CON) and from soils amended with calcitic lime (CAL), and lime (LSB)- and cement kiln dust (CDB)-sanitized biosolids were characterized by chemical analysis and Pyrolysis-Gas chromatography (Py-GC). From diethyl ether (DEE) and CHCl3 soluble lipids, and from weight ratios of the extracts, the organic matter in the soil amended with CDB-treated biosolids seemed to be more biodegraded and biochemically inert than the organic matter in soils that received LSB-treated biosolids and calcitic lime and that in the control soil. Pyrolysis-gas chromatography of extracts of the control soil and the soil treated with lime (CAL) showed the presence of n-alkanes (n-C13 to n-C33), alkenes (C16:1 to C30:1), n-fatty acids (n-C16 to n-C32), and the unsaturated C18:1 and C18:2 fatty acids. The application of LSB and CDB biosolids increased the relative abundance of unsaturated aliphatics. In general, the presence of relatively high concentrations of unsaturated aliphatics in the DEE extracts was an indicator of high biological activity. Thus, in terms of decreasing biological activity, the three treatments could be ranked in the following order: LSB>CDB>CAL. The application of CDB-treated biosolids was more drastic than any of the other treatments and led to excessive removal by leaching and/or degradation of many lipid components and a reduction in molecular diversity. Continuous applications of sanitized biosolids are likely to bring about significant changes in the quality of the lipid fraction of SOM.