Impact of treated sewage sludge application on phosphorus release kinetics in some calcareous soils

• Published in: Environmental earth sciences Vol. 55; no. 5; pp. 1015 - 1021
• Main Authors: Hosseinpur, Alireza, Pashamokhtari, Hamed
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.09.2008; Springer; Springer Nature B.V
• Subjects: Calcareous soils; Calcium carbonate; Calcium chloride; Cation exchange; Correlation coefficient; Earth and Environmental Science; Earth Sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental science; Exact sciences and technology; Geology; Iran; Kinetics; Organic matter; Original Article; Phosphorus; Pollution, environment geology; Sewage sludge; Sewage treatment; Sludge; Soil amendment; Soil properties; Soil treatment; Soils; Studies; Surficial geology; Wastewater treatment; Middle East; Iran; Asia; Calcareous soils; Phosphorus; Iran; Release kinetics; Sewage sludge; models; diffusion; cation exchange capacity; runoff; extraction; pollution; carbonates; sewage sludge; Calcareous soils .Phosphorus; agriculture; calcium carbonate; Sewage sludge .Release kinetics .Iran; organic materials; soils; kinetics; desorption; correlation coefficient; phosphorus
• ISSN: 0943-0105; 1866-6280; 1432-0495; 1866-6299
• DOI: 10.1007/s00254-007-1050-x

Treated sewage sludge contains significant amount of phosphorus and is widely used in agriculture. Kinetics of P release in soils is a subject of importance in soil and environmental sciences. There are few studies about P release kinetics in treated sewage sludge amended soils. For this purpose, sludge was mixed with ten soils at a rate equivalent to 100 Mg sludge ha −1 , and P desorption was determined by successive extraction using 0.01 M CaCl 2 over a period of 65 days at 25 ± 1°C. Phosphorus release rate was rapid at first (until about first 360 h) and then became slower until equilibrium was approached. Average of P released within 360 h for the unamended and amended soils was about 65 and 73% of the total desorbed P, respectively. Zero-order, first-order, second-order, power function, simplified Elovich and parabolic diffusion law kinetics models were used to describe P release. First-order, Elovich, power function and parabolic diffusion models could well describe P release in the unamended and amended soils. Correlation coefficients between P release rate parameters and selected soil properties showed that in the control soils, calcium carbonate equivalent and Olsen-extractable P; and in the amended soils, calcium carbonate equivalent, cation exchange capacity, organic matter and Olsen-extractable P were significantly correlated with P release parameters. The results of this study showed that application of sewage sludge can change P release characteristics of soils and increase P in runoff.