Ash application enhances decomposition of recalcitrant organic matter
Mortensen, Louise Hindborg ; Cruz-Paredes, Carla LU
; Schmidt, Olaf
; Rønn, Regin
and Vestergård, Mette
(2019)
In Soil Biology and Biochemistry
135.
p.316-322
- Abstract
Harvesting whole-tree biomass for biofuel combustion intensifies removal of nutrients from the ecosystem. This can be partly abated by applying ash from the combustion back to the system, as the ash is rich in nutrients. Ash is very alkaline and ash application raises soil pH, which in turn can stimulate microbial activity and thus decomposition and mineralization. Our aim was to test if ash induced decomposition activity was associated with enhanced turnover of recalcitrant, i.e. relatively old, organic pools. Two experiments were conducted in the same coniferous plantation after the application of 0, 3, 4.5 and 6 t ash ha−1, and 0, 3, 9, 15 and 30 t ash ha−1, respectively. We used natural abundance of... (More)
Harvesting whole-tree biomass for biofuel combustion intensifies removal of nutrients from the ecosystem. This can be partly abated by applying ash from the combustion back to the system, as the ash is rich in nutrients. Ash is very alkaline and ash application raises soil pH, which in turn can stimulate microbial activity and thus decomposition and mineralization. Our aim was to test if ash induced decomposition activity was associated with enhanced turnover of recalcitrant, i.e. relatively old, organic pools. Two experiments were conducted in the same coniferous plantation after the application of 0, 3, 4.5 and 6 t ash ha−1, and 0, 3, 9, 15 and 30 t ash ha−1, respectively. We used natural abundance of 15N in mosses, mites and ectomycorrhizal fungi 26 months after ash application, as well as temporal variation in δ15N values of ectomycorrhizal fungi, as an indicator of decomposition of recalcitrant organic matter in the first experiment. Furthermore, in the second experiment we used measurements of extracellular manganese peroxidase activity almost 4 years after ash application as an indication of potential decomposition of lignin, an important component of recalcitrant organic matter. The δ15N signature increased significantly for ectomycorrhizal fungi, dead moss, Nothroid and Gamasida mites, and manganese peroxidase activity tended to increase, with increasing ash doses. This suggests that ash application stimulates turnover of recalcitrant organic matter, which can increase the available pool of nitrogen in the system. This will potentially enhance the fertilizer value of ash. However, the δ15N in ectomycorrhizal fungi tended to peak at 18 months after ash application, before decreasing, suggesting that the turnover of recalcitrant organic matter is reduced again with time.
(Less)
- author
- Mortensen, Louise Hindborg
; Cruz-Paredes, Carla
LU
; Schmidt, Olaf
; Rønn, Regin
and Vestergård, Mette
- publishing date
- 2019-08
- type
- Contribution to journal
- publication status
- published
- keywords
- Manganese peroxidase, Soil food web, Stable isotopes, Wood ash recycling, δ15N
- in
- Soil Biology and Biochemistry
- volume
- 135
- pages
- 316 - 322
- publisher
- Elsevier
- external identifiers
-
- scopus:85066442299
- ISSN
- 0038-0717
- DOI
- 10.1016/j.soilbio.2019.05.021
- language
- English
- LU publication?
- no
- additional info
- Funding Information: This study was supported by the ‘ Center for Bioenergy Recycling – ASHBACK ’ funded by the Danish Council for Strategic Research (grant no. 0606-00587B ). We would also like to thank the forest owner, Steen Blicher A/S, for allowing us to establish the field experiment and ASHBACK collaborators for assisting in establishing and maintaining the site. Publisher Copyright: © 2019 Elsevier Ltd
- id
- e98c0b3f-35a0-4aa9-b6fe-115347d29b01
- date added to LUP
- 2022-08-26 11:35:18
- date last changed
- 2022-09-06 09:39:21
@article{e98c0b3f-35a0-4aa9-b6fe-115347d29b01,
abstract = {{<p>Harvesting whole-tree biomass for biofuel combustion intensifies removal of nutrients from the ecosystem. This can be partly abated by applying ash from the combustion back to the system, as the ash is rich in nutrients. Ash is very alkaline and ash application raises soil pH, which in turn can stimulate microbial activity and thus decomposition and mineralization. Our aim was to test if ash induced decomposition activity was associated with enhanced turnover of recalcitrant, i.e. relatively old, organic pools. Two experiments were conducted in the same coniferous plantation after the application of 0, 3, 4.5 and 6 t ash ha<sup>−1</sup>, and 0, 3, 9, 15 and 30 t ash ha<sup>−1</sup>, respectively. We used natural abundance of <sup>15</sup>N in mosses, mites and ectomycorrhizal fungi 26 months after ash application, as well as temporal variation in δ<sup>15</sup>N values of ectomycorrhizal fungi, as an indicator of decomposition of recalcitrant organic matter in the first experiment. Furthermore, in the second experiment we used measurements of extracellular manganese peroxidase activity almost 4 years after ash application as an indication of potential decomposition of lignin, an important component of recalcitrant organic matter. The δ<sup>15</sup>N signature increased significantly for ectomycorrhizal fungi, dead moss, Nothroid and Gamasida mites, and manganese peroxidase activity tended to increase, with increasing ash doses. This suggests that ash application stimulates turnover of recalcitrant organic matter, which can increase the available pool of nitrogen in the system. This will potentially enhance the fertilizer value of ash. However, the δ<sup>15</sup>N in ectomycorrhizal fungi tended to peak at 18 months after ash application, before decreasing, suggesting that the turnover of recalcitrant organic matter is reduced again with time.</p>}},
author = {{Mortensen, Louise Hindborg and Cruz-Paredes, Carla and Schmidt, Olaf and Rønn, Regin and Vestergård, Mette}},
issn = {{0038-0717}},
keywords = {{Manganese peroxidase; Soil food web; Stable isotopes; Wood ash recycling; δ15N}},
language = {{eng}},
pages = {{316--322}},
publisher = {{Elsevier}},
series = {{Soil Biology and Biochemistry}},
title = {{Ash application enhances decomposition of recalcitrant organic matter}},
url = {{http://dx.doi.org/10.1016/j.soilbio.2019.05.021}},
doi = {{10.1016/j.soilbio.2019.05.021}},
volume = {{135}},
year = {{2019}},
}