Research Perspective on Biological Science Vol. 12

Traditional fermentation methods for animal residues, such as poultry manure, may reduce their nutritional value and the availability of essential elements for crops, while also contributing to environmental pollution and health concerns. Biogas technology may improve organic fertiliser quality because anaerobic digestion occurs under oxygen-free conditions and depends on a balanced microbial system dominated by specialised obligate anaerobic bacteria. This study recycled accumulated raw poultry manure at the research station of the Faculty of Agriculture, Karma Ali, Basra, Iraq. Traditional fermentation methods, including composting and soaking, were compared with a locally manufactured bioreactor equipped with a rotating sieve operating at 4000 rpm min.-1 to separate the produced slurry into solid and liquid fractions. The carboxylic and phenolic groups of the produced organic fertiliser were analysed, and the fertiliser was applied with 0, 50, 75 or 100% of the recommended doses of urea (46% N), superphosphate (47% P2O5) and potash (43% K2O). Treatments were arranged in a randomised complete block design (P < 0.05). The results showed that the highest percentage areas of carboxylic and phenolic groups were recorded in the solid fraction from the bioreactor (68.09 and 2.07%, respectively), compared with soaking (46.38 and 13.18%) and composting (9.41 and 2.07%). Improvements were also observed in soil pH, electrical conductivity, bulk density, total porosity and mean weight diameter. The solid bioreactor fraction, particularly when supported with 75 or 100% of the traditional recommendation, showed the most favourable response.