Home > Research > Publications & Outputs > Combining Multiple High-Resolution in Situ Tech...


Text available via DOI:

View graph of relations

Combining Multiple High-Resolution in Situ Techniques to Understand Phosphorous Availability around Rice Roots

Research output: Contribution to Journal/MagazineJournal articlepeer-review

  • W. Fang
  • P.N. Williams
  • H. Zhang
  • Y. Yang
  • D. Yin
  • Z. Liu
  • H. Sun
  • J. Luo
<mark>Journal publication date</mark>5/10/2021
<mark>Journal</mark>Environmental Science and Technology
Issue number19
Number of pages11
Pages (from-to)13082-13092
Publication StatusPublished
Early online date23/09/21
<mark>Original language</mark>English


Resolving chemical/biological drivers of P behavior around lowland/flooded rice roots remains a challenge because of the heterogeneity of the plant–soil interactions, compounded by sampling and analytical constraints. High-spatial-resolution (sub-mm) visualization enables these processes to be isolated, characterized, and deciphered. Here, three advanced soil imaging systems, diffusive gradients in thin-film technique coupled with laser ablation-ICPMS (DGT-LA-ICPMS), O2 planar optode, and soil zymography, were integrated. This trio of approaches was then applied to a rice life cycle study to quantify solute-P supply, through two dimensions, in situ, and low-disturbance high-resolution (HR) chemical imaging. This allowed mechanisms of P release to be delineated by O2, Fe, and phosphatase activity mapping at the same scale. HR-DGT revealed P depletion around both living and dead rice roots but with highly spatially variable Fe/P ratios (∼0.2–12.0) which aligned with changing redox conditions and root activities. Partnering of HR-DGT and soil zymography revealed concurrent P depletion and phosphatase hotspots in the rhizosphere and detritusphere zones (Mantel: 0.610–0.810, p < 0.01). This close affinity between these responses (Pearson correlation: −0.265 to −0.660, p < 0.01) cross-validates the measurements and reaffirms that P depletion stimulates phosphatase activity and Porg mineralization. The μ-scale biogeochemical landscape of rice rhizospheres and detritusphere, as documented here, needs greater consideration when implementing interventions to improve sustainable P nutrition.