Abstract
To examine the interplay of C and N availability, glucose (high microbial availability) and cellulose (low microbial availability)
were added to soils collected from a temperate forest that had received simulated N deposition for 6 years (organic and/or
inorganic N). The priming effect was higher for glucose addition than for cellulose. N deposition decreased the priming effect of
easily available glucose but increased the priming effect of cellulose. This confirmed an interactive effect of fresh organic matter
(FOM) availability and N deposition on priming. Furthermore, the interactive effect was affected by the form of N deposition,
with interaction mainly observed with organic N deposition. Qualitatively different patterns of priming were observed for the two
FOM types and were accompanied by contrasting abundance of fungi and bacteria in the community, as determined by phospholipid
fatty acid (PLFA) analysis. Organic N deposition increased bacterial biomass but decreased the intensity of priming. In
contrast, a competitive advantage of fungi with respect to organic N sources may drive priming by cellulose. The results
highlighted the importance of the availability of FOM in regulating the priming effect and showed that interactions between
the form of N deposition and the availability of the FOM should be considered when predicting soil C cycling in scenarios of
increased N deposition. Organic N deposition had a greater impact on priming effects than inorganic N deposition, and the
influence of microbial availability of FOM largely depended on organic N deposition.
were added to soils collected from a temperate forest that had received simulated N deposition for 6 years (organic and/or
inorganic N). The priming effect was higher for glucose addition than for cellulose. N deposition decreased the priming effect of
easily available glucose but increased the priming effect of cellulose. This confirmed an interactive effect of fresh organic matter
(FOM) availability and N deposition on priming. Furthermore, the interactive effect was affected by the form of N deposition,
with interaction mainly observed with organic N deposition. Qualitatively different patterns of priming were observed for the two
FOM types and were accompanied by contrasting abundance of fungi and bacteria in the community, as determined by phospholipid
fatty acid (PLFA) analysis. Organic N deposition increased bacterial biomass but decreased the intensity of priming. In
contrast, a competitive advantage of fungi with respect to organic N sources may drive priming by cellulose. The results
highlighted the importance of the availability of FOM in regulating the priming effect and showed that interactions between
the form of N deposition and the availability of the FOM should be considered when predicting soil C cycling in scenarios of
increased N deposition. Organic N deposition had a greater impact on priming effects than inorganic N deposition, and the
influence of microbial availability of FOM largely depended on organic N deposition.
| Original language | English |
|---|---|
| Pages (from-to) | 383-391 |
| Journal | Biology and Fertility of Soils |
| Volume | 55 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - 25 Mar 2019 |
Keywords
- international
- Fresh organic matter
- Microbial availability
- Ndeposition
- Organic N
- Priming effect