Schedule
Time Speaker Title
13:00 – 13:05 Paul Morris & Jane Bunting Welcome and opening remarks
13:05 – 13:35 Colin Courtney Mustaphi Only 999 samples left to do: Tools and techniques for subsampling and portioning wet sediments (hybrid webinar from PSU, USA)
13:35 – 14:05 Antony Blundell Introducing PPSP (Python Peat Stratigraphy Program)
14:05 – 14:25 Muhammad Khan Late-Holocene environmental change at Crowle Moor (undergraduate dissertation; shorter timeslot requested)
14:25 – 14:55 Eline van Asperen Pollen, metal pollution and nature recovery in the northern Lake District
14:55 – 15:25 Cassius Morrison Reconstructions of the ecosystem structure prior to the Cretaceous-Palaeogene Mass Extinction, and implications for extinction mechanisms
15:25 – 15:30 Jane Bunting Closing remarks, AOB
Abstracts
Only 999 samples left to do: Tools and techniques for subsampling and portioning wet sediments
Colin Courtney Mustaphi (U. York and Knowledge Core LLC, Switzerland)
Preparing and processing wet sediment subsamples from split core faces or plastic bags presents unique problems and has been an often overlooked and underappreciated part of paleoenvironmental research. The community is very aware of the challenges and was a common topic in mid-century textbooks on sediment processing and analysis. Subsampling rarely comes up as a topic in modern literature, yet, we speak about it amongst ourselves. Here we explore the literature and opinions of researchers and set the stage to move from ad hoc best practices to improved tools and techniques to raise the standard for analyses, data quality, and method reporting.
Please also see our online questionnaire on laboratory hardware tools
Introducing PPSP (Python Peat Stratigraphy Program)
Antony Blundell (U. Leeds)
Palaeo-environmental and palaeoecological analyses often employ the Troels Smith (1955) scheme in the field to record broad changes in the palaeo archive. TSPPLus (Waller et al., 1995), a DOS based program, was designed to complete this task employing traditional Troels Smith based symbology. PPSP uses a new approach to plot Troels Smith, von Post (von Post 1922, 1924) and charcoal assessments, one that allows extensive visual detail to be retained.
The presentation will convey the general principles behind the program and how to obtain, setup and deploy it. Live demonstrations of the production of example plots will take place. Strengths and areas for improvement will also be examined and hopefully discussed.
Late-Holocene Environmental Change at Crowle Moor
Muhammad Khan (U. Hull)
Crowle Moor is part of the Humberhead Levels and is one of the few remaining lowland raised bogs in eastern England, providing a detailed archive of past environmental change. While regional peatland development is commonly attributed to Holocene Sea level rise, local records of bog surface wetness remain limited, making it difficult to assess how hydrology responded to later climatic variability and human activity. Its long term ecological stability has been shaped by interactions between climate, hydrology, and human disturbance, yet the specific links between these drivers at Crowle Moor remain underexplored.
This dissertation aims to examine an existing sediment core that has already been analysed for pollen and charcoal (Roberts, 2023), through multi-proxy comparison. New plant macrofossil analysis has been undertaken to characterise shifts in peat-forming vegetation and to generate a quantitative hydroclimate index based on changes in peat structure and functional group composition. This index is being compared directly with the established pollen, and charcoal datasets to assess the coherence of proxy signals and to identify key transitions in bog surface wetness, vegetation composition, and wider hydrology.
New plant macrofossil analysis provides the basis for reconstructing past vegetation change at Crowle Moor and for developing a quantitative hydroclimate index. This index captures shifts in bog surface wetness and offers new climate insight not available from previous pollen or charcoal, records done on the same core. Multivariate comparisons, including ordination and constrained analyses, are being used to assess coherence between proxies and will be presented in the meeting.
Pollen, metal pollution and nature recovery in the northern Lake District
E. N. Van Asperen (Newcastle U.), T. Kingham (U. Gloucester), D. W. Rudge (Newcastle U.), and L.-M. Shillito (Durham, U.)
Physical evidence for prehistoric and early historic mining activities is often obliterated by later large-scale mining. Peat cores preserve a record of trace amounts of metals released by metallurgical processes carried out nearby. Furthermore, such processes need large amounts of fuel, and hence their impact can be traced in the vegetation records preserved in the same core. Understanding how the landscape changed over time can inform modern-day nature conservation policy.
We present the results of combined pollen, macrofossil and ICP-MS (trace metals) analysis of peat cores from Miller Moss, northern Lake District. The record covers the part of the Mesolithic up to the present day. Lead pollution starts to rise at the end of the Bronze Age and is correlated with a significant shift in bog wetness. Woodland clearance starts in the late Iron Age. The landscape recovers somewhat in early Medieval times, but further pollution and clearance takes place from around AD 1300.
Through early conversations with nature restoration practitioners, we aim to provide an understanding of how the site responded to pressure in the past and what human drivers were involved. The policy community expressed a particular interest in the location of the treeline and the locations of woodland in the landscape.
Reconstructions of the ecosystem structure prior to the Cretaceous-Palaeogene Mass Extinction, and implications for extinction mechanisms
Cassius Morrison (UCL), Nicolas Stagg (U. Muenster), Caleb Bohus (U. Uppsala) and Charlie Scherer (UCL)
There is much debate concerning the taxonomic diversity of dinosaurs before the most rapid mass extinction in Earth’s history, the Cretaceous-Palaeogene extinction caused by the Chicxulub impact. While some studies have suggested dinosaurs were in taxonomic decline, others suggest the opposite with potential regional variation. The decline in diversity has been associated with less resilient and more vulnerable ecosystems prior to the impact. We proposed to address this debate from a unique angle and assess the stability and vulnerabilities of dinosaurian ecosystems prior to the impact. Here, we use the R package cheddar to recreate the food webs and ecosystem structure in the lead up to the impact in the last 2 million years of the Cretaceous in one of the most explored fossil formations, the Hell Creek Formation. For the first time, we also attempted to assess the plant record to investigate the impact plants had on the dinosaurian fauna. We find evidence for a change in the floral composition prior to the boundary and this likely impacted the dinosaurian fauna. Dinosaurian gregarious behaviour likely impacted ecosystem structure, and we find evidence that Tyrannosaurus rex likely had some degree of gregarious behaviour due to it’s slow growth rate, as otherwise juveniles and sub-adults would be highly vulnerable to expiration, by the contemporary predator Nanotyrannus. Gregarious behaviour likely made species less susceptible to predation but with reduced resources after the bolide impact, species were more vulnerable to extinction. Hell Creek ecosystems were heavily dependent on the plants with no evidence for aquatic resource usage, resulting in high levels of intraspecific competition for any survivors of the initial impact. This technique has the ability to assess ecosystems prior to the impact (or any other ecological perturbation in deep time) and highlight regional variation in ecosystem resilience and the mechanisms of collapse.
Adapted and originally posted 13.04.2026 on YPG https://sites.google.com/view/yorkspalaeogroup/april-2026-meeting-leeds-speakers-and-abstracts?authuser=0