Akademik Veri Yönetim Sistemi
TURKISH JOURNAL OF AGRICULTURE AND FORESTRY, cilt.37, sa.2, ss.179-187, 2013 (SCI-Expanded)
Utilization for agriculture is one of the main disposal methods for sewage sludge. Subirrigated pastures are close to settlements
and under intensive usage. The objective of this study was to investigate the effects of sewage sludge on subirrigated pasture soil and
plant metal concentrations, and the relationship between them. Activated sewage sludge was applied to surface grassland at 25, 50, 75,
and 100 t ha–1 year–1 treatments for 2 years. The concentration of all metals in topsoil (0–20 cm) increased depending on application
dosages, but only Zn concentration increased in subsoil (20–40 cm) consistently. While in the second year the concentration of topsoil
diethylene triamine pentaacetic acid (DTPA) metals increased significantly, it decreased in the subsoil. The ratio of organic matter
increased in topsoil, but decreased in subsoil compared to the control. Doses of sewage sludge of 25 and 50 t ha–1 did not increase the
metal content of herbage. However, the herbage’s Cu, Zn, Pb, and Cd content increased at 75 and 100 t ha–1 treatments in comparison
with both lower doses and the control. Similar to the soil concentration, the Zn content of herbage increased proportionally with
higher sewage sludge application doses. Topsoil DTPA-extractable Zn, Cu, and Pb concentrations were correlated to herbage Zn, Cu,
and Pb content significantly and positively. In subsoil, only DTPA-extractable Cu concentration was correlated to herbage Cu content
significantly and negatively (r = –0.53**). A 25 t ha–1 year–1 application of sewage sludge can be recommended as an organic fertilizer in
semiarid subirrigated pastures, as it increases topsoil organic matter and results in a low concentration of DTPA-extractable and plant
metal content.