The interaction between abiotic photodegradation and microbial decomposition under ultraviolet radiation
© 2014 John Wiley & Sons Ltd.
| Veröffentlicht in: | Global change biology. - 1999. - 21(2015), 5 vom: 24. Mai, Seite 2095-104 |
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| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2015
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| Zugriff auf das übergeordnete Werk: | Global change biology |
| Schlagworte: | Journal Article Meta-Analysis Research Support, Non-U.S. Gov't DOC abiotic degradation lignin litter decomposition meta-analysis microbial activity microbial decomposition mehr... |
| Zusammenfassung: | © 2014 John Wiley & Sons Ltd. Elevated ultraviolet (UV) radiation has been demonstrated to stimulate litter decomposition. Despite years of research, it is still not fully understood whether the acceleration in litter degradation is primarily attributed to abiotic photodegradation or the combined effects of abiotic photodegradation and microbial decomposition. In this study, we used meta-analysis to synthesize photodegradation studies and compared the effects of UV radiation on litter decomposition between abiotic and biotic conditions. We also conducted a microcosm experiment to assess the effects of UV radiation on litter biodegradability and microbial activity. Overall, our meta-analysis found that under abiotic photodegradation, UV radiation reduced the remaining litter mass by 1.44% (95% CI: 0.85% to 2.08%), did not affect the remaining lignin and increased the dissolved organic carbon (DOC) concentration by 14.01% (1.49-23.67%). Under combined abiotic photodegradation and microbial decomposition, UV radiation reduced the remaining litter mass and lignin by 1.60% (0.04-3.58%) and 16.07% (9.27-24.23%), respectively, but did not alter DOC concentration. UV radiation had no significant impact on soil microbial biomass carbon (MBC), but it reduced microbial respiration by 44.91% (2.26-78.62%) and altered the composition of the microbial community. In addition, UV radiation reduced nitrogen (N) immobilization by 19.44% (4.77-37.92%). Our microcosm experiment further indicated that DOC concentration and the amount of respired C in UV-treated litter increased with UV exposure time, suggesting that longer UV exposure resulted in greater biodegradability. Overall, our study suggested that UV exposure could increase litter biodegradability by increasing the microbial accessibility of lignin, as well as the labile carbon supply to microbes. However, the remaining litter mass was not different between the abiotic and biotic conditions, most likely because the positive effect of UV radiation on litter biodegradability was offset by its negative effect on microbial activity. Our results also suggested that UV radiation could alter the N cycle during decomposition, primarily by inhibiting N immobilization |
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| Beschreibung: | Date Completed 14.01.2016 Date Revised 20.04.2015 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1365-2486 |
| DOI: | 10.1111/gcb.12812 |