Root induced soil deformation influences Fe, S and P: rhizosphere chemistry investigated using synchrotron XRF and XAS.
Root induced soil deformation influences Fe, S and P: rhizosphere chemistry investigated using synchrotron XRF and XAS.
复制标题
根引起的土壤变形影响 Fe、S 和 P：使用同步加速器 XRF 和 XAS 研究根际化学。
DOI：
10.1111/nph.16242
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
T. Roose
中科院分区：
文献类型：
--
作者：
A. Veelen;N. Koebernick;Callum S. Scotson;Daniel McKay;T. Huthwelker;C. Borca;J. F. W. Mosselmans;T. Roose
微球土壤具有与非微球土壤不同的理化性质。然而，除了根引起的物理变化，化学变化还没有被广泛地测量原位孔隙尺度。在这项研究中，我们耦合的结构信息，以前获得的同步加速器X射线计算机断层扫描（XCT），同步加速器X射线荧光（SR-XRF）显微镜和X射线吸收近边结构（XANES）解开植物根系引起的化学变化。我们的研究结果表明，铁（Fe）和硫（S）显着增加，在直接附近的根通过溶解和微生物活性。XANES进一步表明，在该富集带中，Fe略有减少，S逐渐转化为硫酸盐（SO 42-），磷（P）逐渐被腐殖物质吸附。此外，水铁矿分数急剧下降，表明优先溶解和更稳定的铁氧化物的形成。此外，有机硫向硫酸盐转化的增加表明该区域的微生物活性增强。土壤化学的这些变化对应于先前通过X射线CT测量的土壤压实区。这些变化共同位于根和压实区附近的事实表明，由于土壤结构变化导致的渗透性降低作为一个屏障，通过表面介导的过程，微生物活性和酸化，产生了一个根际化学相互作用增加的区域。
Rhizosphere soil has distinct physical and chemical properties from bulk soil. However, besides root induced physical changes, chemical changes have not been extensively measured in situ on the pore scale. In this study we couple structural information, previously obtained using synchrotron X-ray computed tomography (XCT), with synchrotron X-ray Fluorescence (SR-XRF) microscopy and X-ray Absorption Near-Edge Structure (XANES) to unravel chemical changes induced by plant roots. Our results suggest that iron (Fe) and sulfur (S) increase notably in the direct vicinity of the root via solubilization and microbial activity. XANES further shows that Fe is slightly reduced, S is increasingly transformed into sulfate (SO4 2- ) and that phosphorus (P) is increasable adsorbed to humic substances in this enrichment zone. In addition, the ferrihydrite fraction decreases drastically suggesting the preferential dissolution and the formation of more stable Fe-oxides. Additionally, the increased transformation of organic S to sulfate indicates that the microbial activity in this zone is increased. These changes in soil chemistry correspond to the soil compaction zone as previously measured via X-ray CT. The fact that these changes are co-located near the root and the compaction zone suggests that decreased permeability due to soil structural changes acts as a barrier creating a zone with increased rhizosphere chemical interactions via surface mediated processes, microbial activity and acidification.
使用 X 射线 CT 和 MRI 根部粘液降解的相关可视化
影响因子：
4.6
作者：
Van Veelen A
通讯作者：
Van Veelen A
DOI：
10.1039/c4dt03559c
发表时间：
2015-04-14
期刊：
Dalton transactions (Cambridge, England : 2003)
影响因子：
--
作者：
Johnstone TC;Nolan EM
通讯作者：
Nolan EM