Study on the Characteristic UV Absorption Parameters of Dissolved Organic Matter Extracted from Chicken Manure during Composting

The characteristic parameters obtained from UV Visible spectra of dissolved organic matter (DOM) during composting were studied in the present paper The results showed that during composting progress the non humic substances were translated into humus substances and the aromatization humification degree and molecular weight of the humus substances in creased while the fatty chains linked with the benzene ring structure were cleavaged into carbonyl carboxyl and other functional groups The correlation analysis showed that when DOM concentration (DOC) from all samples was the same the specific ultraviolet absorbance values at 254 and 280 nm (SUVA(254) and SUVA(280) respectively) and the area of a spectrum obtained from 226 to 400 rim (A(226) (400)) showed significant positive correlation furthermore they were all significantly negatively correlated with the concentration of DOM (DOC) but the correlation between A(226-400) and DOC was the best The ratio between the absorbance value at 253 nm and that at 203 nm (E-253/E-203) was significantly correlative with SUVA(254) SUVA(280) and A 226 400 though the correlation between E-253/E-203 and DOC was not as good as the other three characteristic parameters The ratio be tween the absorbance value at 250 non and that at 365 nm (E-250/E-365) and the ratio between the absorbance value at 465 nm and that at 665 nm(E-250/E-365) were not correlated with the other parameters The results showed that the stability of DOM extracted from chicken manure increased during composting and the complex ability between DOM and heavy metals enhanced as well A(226) (400) reflects the changes of compost maturity best in all UV Visible spectral absorption parameters studied in this paper