Assessment the Effect of Compost Amendments on Soil Characteristics and Barley Plant

This study aimed to evaluate the effects of three different types of commercial compost, i.e., Animal Manure Compost (AMC), Crop Manure Compost (CMC) and Town Refuse Compost (TRC) on some chemical and spectroscopic characteristics of sand soil, as well as growth and yield barley plant (Hordum vulgar cv. Giza 123). They were individually applied at rate of 2% (oven-dry basis) and incubated for 56 days, and then Humic Acids (HA) and Fulvic Acids (FA) fractions were extracted and analyzed using total acidity and UV-Vis spectroscopy. From UV-Vis absorption spectra the absorbance ratios E4/E6 have been calculated. Soil pH, EC, and organic carbon content were determined. In addition, compost-N mineralization and nitrification rates were assessed. The results showed that the soil treated with organic amendment had higher values of organic matter, EC and available N as Compared with the unamend soil. Soil compost amendments had positive effect on mineralization, as the Net-N release increased with incubation time. The E4/E6 ratios of HA fraction in soil treatments ranged from 3.2 to 7.6, while the E4/E6 ratios of FA were higher than that of HA values (4.3-9.5). On the other hand, total acidity of function group for FAs was much greater than that for HAs (0.6-10.6 meq g−1 fulvic material). The results showed that addition of composts significantly (at P≤0.05) increased barley grain, straw weight and total yield compared to control (no compost application).