Changes in some chemical characteristics of compost treated with energetic substances and microbial inoculants

الملخص EN

The main point of this study is the production of organic compost as an alternative source of nutrient and in the same time to reduce the environmental hazards caused by excessive application of chemical fertilizers.

In this respect, the farm wastes (plant residues plus animal manure) were collected and treated with different energetic substances and microbial inoculants, in different ratios and combinations, to produce different compost forms.

The composting process was carried out in cement tanks constructed in the field and designed with bottom outlet for collecting the compost tea (filtrate) to be used as a source of organic nutrients.

Different characteristics of composted materials were determined to evaluate the quality and maturity of produced combinations.

Samples of composted materials were collected for laboratory analyses with intervals begin from 24 hrs (0 time) up to 60 days.

The given data revealed that pH values of composted materials tended to increase with time up to 60 days of incubation.

This holds true with different composting treatments.

In the same time, pH values were fluctuated according to composting treatments.

Electrical conductivity (EC) values tended to increase up to 30 days and the highest values was recorded with T6 and the lowest one was recorded with T4.

Both the treatments and incubation period have significant effects on nitrogen content of the composted materials.

Also, T6 was the best treatment, which enriched the composted materials.

The C/N ratio was decreased during the composting process.

The initial ratio of C/N, which ranged between 22 and 72, substantially decreased in all windrows depending on its chemical composition.

The originated organic matter was more able to degrade with time progress up to 60 days of incubation.

In the same time, the addition of T6 had encouraged this process of degradation (mineralization of organic N).

It seems that phosphorus percent in compost was frequently affected by additives.

The highest percent of P was induced by application treatments at 60-day interval while the lowest one was noticed after 30 day of incubation.

We can conclude that the compost was richness in K+ content at 60 day, which we believe it is the mature stage, when T4 and T6 were applied.

Micronutrients in composted materials showed frequent trends, for example the highest values of Fe in compost, despite of treatments, were detected at 60 days interval.

The overall mean of treatments indicated the superiority of T1 over the others followed by T5.

It is obvious that the Cu content of compost was significantly increased with progress of incubation time intervals.

At the same time, T6 treatment was superior over the other treatments as indicated from the overall average.

Mn content was increased with time interval progress.

The best value of Mn content was occurred at 15-day incubation interval as compared to others.

It positively affected by composting treatments.

The content of Zn was fluctuated along with time intervals depending on composting treatments.