Nutrient leaching potential following application of papermill lime-sludge to an acidic clay soil

Abstract

SUMMARYThis experiment was carried out under greenhouse conditions with soil pots during 210 days, to evaluate the effect of calcitic papermill lime-sludge application (at the rates 0, 773, 1.547, and 2.320 mg kg -1 or respective equivalents to control, 2, 4, and 6 t ha -1 ), on chemical composition of soil leachate and its effects on eucalypt growth and yield. Highest soil leachate pH, SO 4 , and Na concentrations occurred in the 4 and 6 t ha -1 treatments. Soil leachate nitrate concentrations decreased with increasing lime-sludge rate. Soil leachate phosphate remained low (below the detection limit) in all treatments until 120 days, while the concentration increased in the lime-sludge treatments at 210 days (last sampling) in about 600 mg L -1 . Lime-sludge decreased leachate Mg concentration, but had no significant effect among rates. Soil leachate Ca, K, B, Cu, Fe, and Zn did not change significantly for any lime-sludge application rates. The maximum NO 3 , Ca, Mg, K, and Na concentrations in the soil leachate occurred at 60 days after lime-sludge application (leaching equivalent to 1 pore volume), but for pH and SO 4 , the maximum occurred at 210 days (leaching equivalent to 4 pore volumes). Lime-sludge application decreased the concentration of exchangeable Al in the soil. Plant diameter growth and dry matter yield were increased with increasing lime-sludge rate. Beneficial effects on mineral nutrition (P, K, Ca, B, and Zn) of eucalypts were also obtained by the application of 4 and 6 t ha -1 of lime-sludge.Index terms: eucalypt, industrial residue, soil fertility, mineral nutrition, sodium, recycling.(

Impact of Sewage Sludge Leaching on Soil Constituents and Quality

“…The sewage sludge contains high amounts of toxic metals (Cesar et al, 2012). These sludge constituents are subjected to leaching by rainwater (Vettorazzo et al, 2001;Lehmann et al, 2003), and thereby liable to contaminate soil, water, and produce (Keller et al, 2002;Lavado et al, 2007), which limit the use of sludge in agriculture (Chaudri et al, 2000;Mosquera-Losada et al, 2010).…”

Polyhydroxyalkanoate production by Bacillus thuringiensis: an aspect of biorefining pulp and paper mill sludge.

“…High soluble salt levels, particularly sodium are also problematic; furthermore, there is concern over groundwater contamination and affects caused by potential leaching of nitrates and heavy metals. Land-spreading sludge material must be used very carefully as an unfavorable carbon: nitrogen ratio or high ion exchange capacity can affect the growth of plants, and there is the possibility of chromium toxicity (Vettorazzo et al 2001;Baggs 2002). Secondary sludges which contain chlorinated organic compounds (or absorbable organo-halogens) may not be used as soil improving organic fertilizers, as most of these are acutely toxic to fauna and flora (Rosazlin et al 2010).…”