Azolla as a Source of Organic Nitrogen and its Role in Recycling Agricultural Residues and Improving the Quality of Compost

Composting is a process which converting the various components in organic residues into relatively stable humus-like substances that can be used as organic fertilizer or soil amendment. The aim of this study was to research the role of Azolla pinnata for improving the quality of compost produced from date palm trees frond residues. Treatments included two types of composts: C1) Palm tree fronds + Azolla + microbial inoculum, C2) Palm tree fronds + chemical activator (45kg ammonium sulfate +10 kg superphosphate /t plant residues) + microbial inoculum. For all treatments the initial C/N ratio was 37:1. The results showed that the temperature was increased to 67 and 68.34 oC for C1 and C2, respectively and then decreased by the end of the composting period to 19.5 oC for two treatments. The final product had brown color and natural soil odor, and C/N ratio was 16:1 and 18:1, EC was 2.60, 2.47 dSm-1, and recorded total nitrogen was 1.78, 1.70 for mixt 1 and 2 respectively. The results found that adding Azolla for date palm trees frond residues compost improve compost quality comparing with compost from Palm tree fronds + chemical activator.