Abstract
A silt loam soil from Pakistan was incubated at 30°C with increasing levels (67, 133, 200, 267 and 333 μg N g-1 soil) of15N-labelled (NH4)2SO4 and glucose (C/N ratio of 30 for all additions). At a stage when all of the applied15N was immobilized (transformed into microbial biomass), moist soil samples were subjected to the chloroform fumigation-incubation method (CFIM) for determination of KN and microbial biomass. Mineralization of biomass derived from the applied15N and the native soil N was studied under anaerobic conditions. In situ values of KN varied from 0.19 to 0.42 and increased with increasing levels of amendment (N + glucose). From 10 to 18% of the native soil N was found as microbial biomass. Anaerobic incubation of the soils resulted in the mineralization (determined as NH4+) of 15.08 to 29.23% of the biomass15N at different levels of amendment; 2.90 to 4.43% of the native soil N was mineralized. From 70 to 90% of the N mineralized from native soil N was derived from microbial biomass; the rest was attributed to non-biomass N.
Original language | English (US) |
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Pages (from-to) | 87-93 |
Number of pages | 7 |
Journal | Plant and Soil |
Volume | 111 |
Issue number | 1 |
DOIs | |
State | Published - Sep 1988 |
Keywords
- N immobilization
- N mineralization
- anaerobic incubation
- chloroform fumigation
- microbial biomass
ASJC Scopus subject areas
- Soil Science
- Plant Science