TY - JOUR

T1 - Plant intraspecific competition and growth stage alter carbon and nitrogen mineralization in the rhizosphere

AU - Sun, Yue

AU - Zang, Huadong

AU - Splettstößer, Thomas

AU - Kumar, Amit

AU - Xu, Xingliang

AU - Kuzyakov, Yakov

AU - Pausch, Johanna

N1 - Publisher Copyright: © 2020 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

PY - 2021/4/1

Y1 - 2021/4/1

N2 - Plant roots interact with rhizosphere microorganisms to accelerate soil organic matter (SOM) mineralization for nutrient acquisition. Root-mediated changes in SOM mineralization largely depend on root-derived carbon (root-C) input and soil nutrient status. Hence, intraspecific competition over plant development and spatiotemporal variability in the root-C input and nutrients uptake may modify SOM mineralization. To investigate the effect of intraspecific competition on SOM mineralization at three growth stages (heading, flowering, and ripening), we grew maize (C4 plant) under three planting densities on a C3 soil and determined in situ soil C- and N-mineralization by 13C-natural abundance and 15N-pool dilution approaches. From heading to ripening, soil C- and N-mineralization rates exhibit similar unimodal trends and were tightly coupled. The C-to-N-mineralization ratio (0.6 to 2.6) increased with N availability, indicating that an increase in N-mineralization with N depletion was driven by microorganisms mining N-rich SOM. With the intraspecific competition, plants increased specific root lengths as an efficient strategy to compete for resources. Root morphologic traits rather than root biomass per se were positively related to C- and N-mineralization. Overall, plant phenology and intraspecific competition controlled the intensity and mechanisms of soil C- and N- mineralization by the adaptation of root traits and nutrient mining.

AB - Plant roots interact with rhizosphere microorganisms to accelerate soil organic matter (SOM) mineralization for nutrient acquisition. Root-mediated changes in SOM mineralization largely depend on root-derived carbon (root-C) input and soil nutrient status. Hence, intraspecific competition over plant development and spatiotemporal variability in the root-C input and nutrients uptake may modify SOM mineralization. To investigate the effect of intraspecific competition on SOM mineralization at three growth stages (heading, flowering, and ripening), we grew maize (C4 plant) under three planting densities on a C3 soil and determined in situ soil C- and N-mineralization by 13C-natural abundance and 15N-pool dilution approaches. From heading to ripening, soil C- and N-mineralization rates exhibit similar unimodal trends and were tightly coupled. The C-to-N-mineralization ratio (0.6 to 2.6) increased with N availability, indicating that an increase in N-mineralization with N depletion was driven by microorganisms mining N-rich SOM. With the intraspecific competition, plants increased specific root lengths as an efficient strategy to compete for resources. Root morphologic traits rather than root biomass per se were positively related to C- and N-mineralization. Overall, plant phenology and intraspecific competition controlled the intensity and mechanisms of soil C- and N- mineralization by the adaptation of root traits and nutrient mining.

KW - C natural abundance

KW - N pool dilution

KW - arable soil

KW - carbon and nitrogen mineralization

KW - intraspecific competition

KW - maize

KW - root traits

KW - soil organic matter decomposition

KW - Ecosystems Research

KW - Biology

UR - http://www.scopus.com/inward/record.url?scp=85097545765&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/fea542f9-b870-353d-9b0b-42748240b61e/

U2 - 10.1111/pce.13945

DO - 10.1111/pce.13945

M3 - Journal articles

C2 - 33175402

AN - SCOPUS:85097545765

VL - 44

SP - 1231

EP - 1242

JO - Plant, Cell and Environment

JF - Plant, Cell and Environment

SN - 0140-7791

IS - 4

ER -