Background Vegetation fire may change Phosphorus (P) cycling in terrestrial ecosystems through converting biomass into fire residues. Aim The aim of this study was to understand the chemistry and mobility of P in fire residues to help reveal P thermochemistry during biomass burning and post-fire P cycling. Methods A combination of sequential extraction, liquid 31P NMR and P K-edge XANES was used to obtain quantitative P speciation and explain P solubilisation behaviours of charcoal. Key results Despite varying diverse P species existing in raw biomass, only two P structural moieties – orthophosphate and pyrophosphate – were identified in charcoal. However, relative abundance of pyrophosphate differs greatly among charcoal samples from different biomass types, ranging between 0 and 40% of total extractable P. Although P K-edge XANES data indicates abundant soluble phosphate minerals, most P (70–90%) is likely occluded physically in the charcoal. The bicarbonate-extractable P (the Olsen-P) varies significantly and cannot be explained by surface P concentration or elemental stoichiometry alone. Conclusion and implications The results suggest the importance of starting biomass P speciation (i.e. molecular structure and complexation environment) and thermal conditions in controlling P speciation and availability in charcoal. The different P chemistry between charcoal and ash suggests the importance of fire types and severity in disturbing the P cycle.
This content will become publicly available on October 25, 2024
Rate-dependent stress-order coupling in main-chain liquid crystal elastomers
This study reports rate-dependent measurements and relaxation of stress, director rotation, and shear strain in main-chain nematic LCEs subjected to uniaxial tension with various initial directors, which is further explained by an analytical model.
more » « less- Award ID(s):
- 1925790
- NSF-PAR ID:
- 10494556
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 19
- Issue:
- 41
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 7923 to 7936
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Date Presented 04/21/2023
When working with autistic individuals, OTs need to incorporate interest-based activities in inclusive environments that promote protective factors and improve mental health and well-being.
Primary Author and Speaker: Joana Nana Serwaa Akrofi
Additional Authors and Speakers: Dora Onwumere
Contributing Authors: Kavitha Murthi, Kristie Patten, Ariana Riccio, Wendy Martin
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