Abstract
A sandy soil was amended with different types of sewage sludge (digested, dried, and composted) and pig slurry. The composted sludges displayed higher organic-matter stability (39-45%) than only digested sludge (26-39%) or digested + dried sludge (23-32%). The microbial biomass of the dried sludge was undetectable. Digested and composted sludges and pig slurry displayed microbial biomasses (12492-13887 μg g-1, 1221-2050 μg g-1, and 5511 μg g-1, respectively) greater than the soil (108 μg g-1). The wastes were applied at seven doses, ranging from 10 to 900 g kg-1. Soils were incubated for 28 days. Substrate-induced respiration (SIR) was measured for 12 consecutive hours on day 1 and on day 28. The results showed that SIR increased with the dose of organic amendment. However, SIR decreased when moderate doses of pig slurry or high doses of digested + dried sludge were tested. The possibility of using this inhibition as an ecotoxicological indicator is discussed. © Taylor & Francis Group, LLC.
Original language | English |
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Pages (from-to) | 408-423 |
Journal | Communications in Soil Science and Plant Analysis |
Volume | 41 |
DOIs | |
Publication status | Published - 1 Jan 2010 |
Keywords
- Pig slurry
- Priming effect
- Sewage sludge
- Soil respiration
- Standardized test
- Toxicity