METHOD OF EVALUATING AVAILABLE NITROGEN CONTENT OF LIVESTOCK DUNG COMPOST

摘要

PROBLEM TO BE SOLVED: To provide a means for rapidly and easily estimating the available nitrogen content of livestock dung compost.;SOLUTION: A method of evaluating the available nitrogen content of livestock dung compost includes the following processes (a)-(d), namely (a) extracting a livestock dung compost sample by acid with a hydrogen ion concentration of 0.8 to 2.0 mol/L, (b) measuring absorbance at a wavelength within a range of 400 to 500 nm, the amount of ammonia nitrogen, and the amount of nitrate nitrogen for an extraction liquid obtained in (a), (c) obtaining the amount of organic form nitrogen of a compost sample extraction liquid according to the absorbance measurement value obtained in (b) by a regression formula expressing a correlation relationship between the absorbance of the acid extraction liquid of the livestock dung compost and the amount of organic form nitrogen in the extraction liquid, and (d) evaluating the available nitrogen content of the livestock dung compact sample with the total of the amount of ammonia nitrogen and the amount of nitrate nitrogen obtained in (b) and the amount of organic form nitrogen obtained in (c) as an index.;COPYRIGHT: (C)2010,JPO&INPIT