Publication Details |
| Category | Text Publication |
| Reference Category | Journals |
| DOI | 10.1016/j.soilbio.2023.109212 |
| Title (Primary) | Contrasting mechanisms of nutrient mobilization in rhizosphere hotspots driven by straw and biochar amendment |
| Author | Shang, W.; Razavi, B.S.; Yao, S.; Hao, C.; Kuzyakov, Y.; Blagodatskaya, E.; Tian, J. |
| Source Titel | Soil Biology & Biochemistry |
| Year | 2023 |
| Department | BOOEK |
| Volume | 187 |
| Page From | art. 109212 |
| Language | englisch |
| Topic | T5 Future Landscapes |
| Keywords | Rhizosphere extent; Microbial hotspots; Microbial growth strategy; Zymography; Enzyme kinetics |
| Abstract | Straw return strategies are widely used green management practices that can
alter soil organic matter transformation and dynamics through changes in microbial
community structure and functions. How the exogenous input of organic materials
of contrasting qualities affects the composition of dominant taxa, growth, and
microbial functional properties related to nutrient acquisition in space
remains unclear. In this study, we investigated the hotsopts and kinetics of C-
and N-acquiring hydrolases, microbial growth, and bacterial community structure
in maize rhizosphere hotspots after the addition of straw and straw-derived
biochar using soil zymography, substrate-induced respiration and
high-throughput sequencing. Compared with no amendment and maize straw-derived
biochar, straw addition increased the growing biomass and microbial specific
growth rate by 1.2–1.6 and 1.7–2.0-fold, respectively, indicating the relative
dominance of fast-growing r-strategists. This corresponds to an increased
relative abundance of the keystone taxa Firmicutes and their gene
copies encoding β-1,4-glucosidase (BG) and β-N-acetylglucosaminidase
(NAG). The potential activity and affinity (Vmax and Km)
of BG increased 2.2 and 1.8 times, respectively, and those of NAG increased 4.0
and 2.0 times, respectively. In contrast, the relative abundance of Actinobacteria
belonging to K-strategists increased in the biochar-amended soil. This
resulted in slower growth and retarded enzymatic activity than the straw return
treatment. Biochar enhanced the root biomass by 31% and increased the
rhizosphere hotspot extents of BG and NAG by 26% and 47%, respectively. The
highest robustness and modularity of the co-occurrence network indicated a more
stable network with biochar input. In summary, the addition of straw
accelerated rhizosphere nutrient cycling by triggering microbial growth,
especially fast-growth r-strategists (Firmicutes), and
synthesizing a large number of enzymes. In contrast, the addition of biochar
increased rhizosphere nutrient mobilization by expanding the extent of
rhizosphere hotspots to mobilize nutrients from a larger soil volume. This
suggests that there are different strategies for nutrient mobilization in the
rhizosphere with contrasting exogenous C addition.
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| Persistent UFZ Identifier | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=28088 |
| Shang, W., Razavi, B.S., Yao, S., Hao, C., Kuzyakov, Y., Blagodatskaya, E., Tian, J. (2023): Contrasting mechanisms of nutrient mobilization in rhizosphere hotspots driven by straw and biochar amendment Soil Biol. Biochem. 187 , art. 109212 10.1016/j.soilbio.2023.109212 |
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