Bülent Turgut

Improvements in aggregate stability of sediments supplemented with tea waste and farmyard manure

The influence of organic matter amendments on soil aggregate stability is well known, but the corresponding changes in recently deposited sediment are not well documented. In this study, improvements in aggregate stability of recently deposited sediment (RDS) supplemented with farmyard manure (FYM) and tea waste (TW) were evaluated during an 18-week incubation period under controlled conditions. FYM and TW were applied to RDS at different rates (0%, 2.5%, 5%, 7.5%, 10%, 12.5% and 15% w/w), and aggregate stability was determined at different times of incubation (2nd, 4th, 6th, 8th, 10th, 14th, and 18th weeks) using wet sieving analysis. The results showed that the aggregate stability of RDS treated with TW was statistically significantly higher than those of samples treated with FYM. Aggregate stability increased with increasing rates of both FYM and TW. Aggregate stability reached the highest value at the end of the second week in FYM treated samples, and declined within the following incubation period. However, in the samples treated with TW, aggregate stability reached the highest value at the end of the eighth week. Since the results of this study clearly indicated that tea waste and farmyard manure input significantly increased the aggregate stability of RDS, it is suggested that TW and FYM could be used for structural stabilization of degraded soils.