Tracing Plant- and Microbial Carbon and Nutrients Pathways in Soil with Isotope and Imaging Techniques

Plant-soil interactions form vital links between abiotic and biotic soil components and provide hotspots for microbial processes. Isotope techniques and soil enzyme kinetics are often used to unravel the complex and diverse interactions between roots, soil particles, and biota. This study aims to elucidate further C and N turnover in the rhizosphere in maize production systems and P mobilization in the detritusphere of beech forests, guide sustainable soil management, and develop new visualization technologies for rhizosphere investigation. To investigate the potential for resource reuse in agricultural soil, 13C and 15N were used to trace C and N uptake by maize from root channels of cover crop mixtures. Results show that the legume/grass allocated the most C and N to subsoil root channels, with maize taking up to 6.5% of N from these root channels. Legume/grass and brassica/grass enhanced enzyme activities in maize rhizosphere under drought, suggesting the potential for enhancing C stabilization and N supply during maize growth under drought. In addition, whether microorganisms maintain high P mobilization when microbial diversity decreases was investigated using 33P as a tracer. The high functional redundancy of microbial P mobilization with the rapid litter-P acquisition of microorganisms was observed in P-deficient soil. Moreover, new approaches of micro-zymography with fluorescent substrates to visualize peroxidase activity on root tissue and fluorescence lifetime imaging microscopy with phasor plot separation to differentiate stained microorganisms from soil particles were established, enhancing our knowledge of microorganism localization in complex soil matrices. The outcome of this study contributes to a better understanding of C and nutrient pathways in the soil, provides sustainable strategies for agricultural and forest soil management, and offers powerful tools for future soil biochemistry research.

Rights

Use and reproduction:


CC BY 4.0

Please note that individual components of the publication may be subject to other licensing or copyright conditions.

Cite

Citation style:
Could not load citation form.