Organic fertilizer from agricultural waste: determination of phosphorus content using near infrared reflectance

Agricultural waste can be converted onto useful materials like compost or organic fertilizers. In a simply practice, those wastes were kept and mixed with additional composting materials to enrich the fertilizer nutrients and compositions. Generally, plants can growth optimally in sufficient media, that is soil. It requires adequate micro and macro nutrients like phosphorus (P). in order to determine P content and other nutrient properties, many methods have been widely used from which most of them are wet chemical analysis. The main aim of this present study is to employ the near infrared reflectance (NIRS) technique in determining P content of organic fertilizer. Spectra data were generated in wavenumbers 5000 - 10 000 cm(-1) and the model were established using principal component regression (PCR) method. The results showed that P content of compost materials can be determined using MRS with maximum correlation coefficient 0.99 and robustness index 4.14 respectively.