Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.soilbio.2022.108850
Title (Primary) Frequent carbon input primes decomposition of decadal soil organic matter
Author Zhou, J.; Guillaume, T.; Wen, Y.; Blagodatskaya, E.; Shahbaz, M.; Zeng, Z.; Peixoto, L.; Zang, H.; Kuzyakov, Y.
Source Titel Soil Biology & Biochemistry
Year 2022
Department BOOEK
Volume 175
Page From art. 108850
Language englisch
Topic T5 Future Landscapes
Keywords 13C natural Abundance; Priming effect; Soil organic matter; Decadal C; C input frequency
Abstract Soil organic matter (SOM) decomposition in response to global change represents a critical uncertainty in coupled carbon (C) cycle-climate models. Much of this uncertainty arises from our limited mechanistic knowledge of organic C input frequency on SOM decomposition. Based on a three-source-partitioning isotopic approach (14C glucose addition to soil continuously labeled by C4 plants over 21 years) and literature review of 86 observations, we assessed the priming effect of fast- and decadal-SOM after occasional and frequent (every 12 vs 60 days) labile C input in a grassland. Frequent glucose input accelerated SOM decomposition over 200 days, but the occasional input reduced this positive priming by 2.6 times. The positive priming by occasional C input resulted in 139 μg C g−1 soil net C sequestration corresponding to 38% of C input. During the 200 days incubation, the primed fast-cycling C (younger than 21 years) under occasional C addition was 52–94% greater compared with frequent addition. Conversely, the priming of decadal SOM (older than 21 years) by frequent C input was 463 μg C g−1 after the 200 days incubation, which represents 5.3% of the initial decadal-cycling soil C pool. This was 1.5 times higher than by occasional input because of the stronger N mining caused by the continuously high activity of microbial K strategists under frequent C input. Our global scale assessment showed that occasional C input reduces the priming of decadal SOM decomposition by 89–127 Tg per year compared to frequent input and thus, sequestrated an additional 102 Tg C per year. Overall, the vulnerability of decadal SOM to increasing C input frequency thus weakening the C sink of grassland, whilst reduced C input frequency (e.g. by drought) suppresses the SOM priming and reduces the positive feedback of SOM decomposition to global change. This points out the necessity to assess the age of soil C when predicting the consequences of altered soil C input frequency under global change.
Persistent UFZ Identifier
Zhou, J., Guillaume, T., Wen, Y., Blagodatskaya, E., Shahbaz, M., Zeng, Z., Peixoto, L., Zang, H., Kuzyakov, Y. (2022):
Frequent carbon input primes decomposition of decadal soil organic matter
Soil Biol. Biochem. 175 , art. 108850 10.1016/j.soilbio.2022.108850