Wendy Hlengiwe Khumalo

• Khumalo, Wendy Hlengiwe; Svarva, Helene Løvstrand; Zurbach, Damaris Charlotte Marie & Nadeau, Marie-Josée (2024). Squeaky Clean Cellulose: Comparing Pretreatment Effectiveness on Single Tree Rings and Wooden Laths. Radiocarbon: An International Journal of Cosmogenic Isotope Research. ISSN 0033-8222. 66(5), p. 1200–1212. doi: 10.1017/RDC.2024.20. Full text in Research Archive Show summary

  Obtaining accurate radiocarbon (14C) results from wood samples requires the extraction of cellulose. In the past, this has been done using different combinations of methods including acidified bleaching, acid-base-acid, and strong bases. This often becomes a time-consuming task in most analyses, especially when single ring isotope chronologies are needed from wood samples. Using 14C and Fourier-transform infrared spectroscopy (FTIR), we tested four different pretreatment methods to determine their ability to produce high quality cellulose. We then adjusted the best methods to determine a method for pretreating wood laths of multiple rings. A sequence of base-acid-base-acid-bleach + strong base (BABAB+) and BABAB produced the most accurate results when compared to the Bomb20 Northern Hemisphere Zone 1 curve with an average difference in Δ14C of 1.3‰ and 5.8‰ respectively. These methods were adjusted to pretreat an entire wood lath and a comparison of the FTIR results suggest that our adjusted BABAB+ and BABAB produced high quality cellulose comparable to that of an individually pretreated ring. The possibility to pretreat wood lath samples has the potential to more than double the number of tree rings which can be pretreated in a week. This is a significant reduction in time when creating long tree ring chronologies.

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• Seiler, Martin Thomas; Philippsen, Bente; Khumalo, Wendy Hlengiwe; Kunisch, Erin Hye Soo & Passerini, Anna-Paola (2025). Atomer avslører kosthold i forhistorien - og kanskje også ditt? doi: https:/www.ntnu.no/forskningsdagene/night/lab-besok. Full text in Research Archive Show summary

  Du kan besøke isotoplaboratoriet på Nasjonallaboratoriene for datering. Du har mulighet å se instrumentene som brukes til måling av isotopforhold i organiske materialer. Vi gjennomfører en live måling av materialet som gruppen kan bestemme eller medbringe selv – kanskje vi analyserer ernæring av en av besøkere. Vi forklarer hvordan instrumentene fungere og hva som skjer mens målinger foregår. Resultatene skal interpreteres i sammenheng med andre materialer og vi forklare hvordan slike målinger brukes i dagens forskning.

• Khumalo, Wendy Hlengiwe; Kallevik, Matias; Svarva, Helene Løvstrand; Nadeau, Marie-Josée; Speed, James David Mervyn & Collet, Dominik (2024). On the margins of agriculture - regional responses to 18th century crises in Norway. Full text in Research Archive
• Seiler, Martin Thomas; Philippsen, Bente; Svarva, Helene Løvstrand; Khumalo, Wendy Hlengiwe; Kunisch, Erin Hye Soo & Ramallo, Patxi Perez (2024). Atomer avslører kosthold i forhistorien - og kanskje også din? Full text in Research Archive
• Khumalo, Wendy Hlengiwe (2024). Dendroclimatology - Reconstructing past climates. Full text in Research Archive
• Pickering, Robyn; Beniest, Anouk; Khumalo, Wendy Hlengiwe & Khoza, Rivoningo (2024). Building meeting grounds between the Global South and North: how do we move away from neo-colonial geoscience research structures. Full text in Research Archive
• Seiler, Martin Thomas; Svarva, Helene Løvstrand; Nadeau, Marie-Josée; Khumalo, Wendy Hlengiwe; Philippsen, Bente & Grootes, Pieter Meiert (2024). Tree-ring C-14 origin seen through the Bombspike magnifying glass. Full text in Research Archive
• Khumalo, Wendy Hlengiwe; Collet, Dominik & Svarva, Helene Løvstrand (2024). A multiproxy comparison of scots pine in Norway. Full text in Research Archive Show summary

  The ClimateCultures projects aims to tackle the question “What happened the last time we encountered rapid climate change?” using evidence from tree rings and historical records to paint a picture of the natural impacts and societal responses in Norway during the Little Ice Age. More specifically, we aim to investigate the short lived extreme cold events in the 1700’s. Norway is particularly well suited to dendroclimatology studies as the cooler climate creates climate sensitive trees growing at their limit (during the summer growing season June-July-August (JJA)). As well as this, the geographical location and the topography of Norway separates the country into different many climate regions. Hanssen-Bauer & Nordli (1998) distinguish six temperature zones and twelve precipitation zones defined by strongly correlating variable time series at climate stations (Figure 1A). In this study we compare the use of Ring Width Index (RIW) chronologies and Blue Intensity Index (BII) chronologies to reconstruct summer temperatures and precipitation in western Norway. In this poster we show preliminary results and highlight the potential of these records to produce quantitative reconstructions

• Khumalo, Wendy Hlengiwe; Kallevik, Matias; Collet, Dominik; Svarva, Helene Løvstrand & Nadeau, Marie-Josée (2023). On the margins of agriculture – regional responses to 18th century crises in Norway. Full text in Research Archive
• Seiler, Martin Thomas; Khumalo, Wendy Hlengiwe & Philippsen, Bente (2023). Radioaktivitet for sporing av karbonkilder: Omvisning i radiokarbonlaboratoriet. Full text in Research Archive
• Seiler, Martin; Rzadeczka-Juga, Izabela; Svarva, Helene Løvstrand; Grootes, Pieter Meiert; Khumalo, Wendy & Nadeau, Marie-Josée (2022). Variation of 14C results from different samples in an archaeological context. Full text in Research Archive
• Seiler, Martin; Svarva, Helene Løvstrand & Khumalo, Wendy (2022). Radioaktivitet som datostempel – bli med på radiokarbonlaboratoriet. Full text in Research Archive
• Khumalo, Wendy Hlengiwe; Svarva, Helene Løvstrand; Zurbach, Damaris & Nadeau, Marie-Josee (2022). Squeaky clean cellulose for different applications. Full text in Research Archive

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