Effects of Compost and Manure Application Rate on the Soil Physico-Chemical Layers Properties and Plant Productivity

The effects of manure and compost application rates on organic carbon (OC) and total nitrogen (TN) contents and their distribution in soil layers as well as basil growth on the amended soils were investigated. Five plots were experimented where the amended substrate was used at a rate of 10% manure, and 10%, 20% and 40% compost, compared to unamended control soil. After 3 months, the soil OC content showed a high mineralization with the compost compared to the manure used at 10%, reflecting a higher biodegradable compost organic matter (OM) fraction that contributed to soil microorganisms activity increase. As a result, a difference in vertical OC distribution in the soil layers was observed. Moreover, the compost rate increase improved the soil cation exchange capacity and the soil base saturation percentage by 41%, 56% and 76%, and by 46%, 77% and 140%, respectively. This improvement indicated the importance of the aggregate established at the 20% and 40% compost rates compared to the 10% compost rate treatment. Basil yields were the highest at low compost rate (10%) treatment. This short term study highlighted the benefits of the compost use and its potential effects on the soil structure and the basil plant productivity improvements while using low amendment rate, exhibiting the high stability of the soil aggregates newly established.