Convenors: Nicki Whitehouse (Queen’s University Belfast, UK), Helen Roe (Queen’s University Belfast, UK) and Carl Sayer (UCL, UK)

Palaeoecology has often been seen to provide only a selective representation of past biological communities. However, over the last decade, with a growing tendency for multi-proxy studies and following various taxonomic and methodological developments, it is clear that this view is far from true. Many species are preserved in sediments, covering the whole spectrum of trophic levels, even including large-bodied organisms (e.g. invertebrates, fish). Thus, the possibility emerges to use palaeo-approaches to track past biodiversity and whole-ecosystem changes and indeed changing ecological interactions over timescales inaccessible to contemporary monitoring studies. Indeed researchers are now able to address a range of ecological and conservation questions regarding biodiversity responses to anthropogenic pressures in a long-term context.

In this session we solicit papers that address the above themes. Papers will be accepted which deal with issues of taphonomy and representivity and, in this context, we especially encourage contributions on less well-studied fossil groups (e.g. invertebrates; fish). We also welcome papers which focus on long-term biodiversity and whole-ecosystem changes in lakes as inferred from multi-proxy studies and through recent analytical advances (e.g. DNA analysis).

Keynote: Professor Tim Patterson
Carleton University, Canada

S14-KN Community structure dynamics and biodiversity across a continuum of past, present and future

Lacustrine sedimentary records archive a time continuum through which species and communities flow as they evolve and undergo ecologic transformations. Although both ecologists and paleoecologists share a common goal of gaining a fuller understanding of biosphere processes, the sedimentary record presents challenges as it provides only a meager sample of past life. These samples are not random but are highly taphonomically biased by a variety of biologic, chemical and sedimentological processes. Any paleolimnologic study must therefore be based on a clear understanding of what can and cannot be achieved with proxy data. With these limitations in mind, there have been recent major advances in paleolimnological research that have improved the ability of paleoecologists to provide a more accurate determination of community structure and biodiversity changes over time. These include: 1) statistical approaches (e.g. improved training sets, transfer functions, better variable selection); 2) improved age modeling (e.g. advanced Bayesian techniques); 3) an increase in multi-proxy studies (e.g. greater paleoenvironmental insight); and 4) higher resolution core analysis (e.g. resulting in improved assessment of community response to environmental cycles, trends and stressors). These advances are discussed in the context of research initiatives where detailed information on paleolimnological trends are required by policy makers and planners to determine the future impact of climate change and success of ongoing remediation efforts, including: 1) climate variability on the long-term viability of the Tibbitt to Contwoyto Winter Road, Northwest Territories; 2) oil sands extraction in Alberta; and 3) road salt contamination and phosphorus loading within the rapidly urbanizing Greater Toronto Area.

List of oral presentations:

• S14-01 Emma Seddon The use of aquatic macroinvertebrate sub-fossil remains to help identify ‘reference conditions’ for the restoration of the River Wensum, Norfolk.
• S14-02 Martin Kernan European Mountain lake Biodiversity: Contemporary patterns and change since the pre-industrial era.
• S14-03 Stephen Brooks Relationships between chironomid diversity and temperature in lakes from Europe and North America
• S14-04 Guangjie Chen Can taxonomic and functional classifications provide similar insight into the diversity-productivity relationship for lake communities? A paleolimnological perspective
• S14-05 Jorge Salgado Long-term changes in diversity linked with eutrophication and dispersal in shallow lake metacommunities.
• S14-06 Jennifer Korosi Subfossil Bosmina size structure as an effective tool to track changes in food web structure
• S14-07 Kathleen Stoof-Leichsenring Cryptic genetic diversity in Staurosira construens from arctic lake sediments

List of poster presentations:

• S14-P-01 Agnese Pujate Reconstruction of paleovegetation changes during the development of Lake Mazais Ungurs according to the plant macrofossil analysis data
• S14-P-02 Agnese Pujate Changes of Lake Engure sedimentation conditions reflected by paleovegetation records
• S14-P-03 Yanmin Cao Spatial distribution of sub-fossil Chironomidae in surface sediments of a large, shallow and hypertrophic lake (Taihu, SE China)
• S14-P-04 Tomáš Bešta Multi-proxy resarch of the exploited former lake, Lake Komorany, Czech Republic
• S14-P-05 Tomáš Bešta Paleoecological study of the littoral profile from the former lake, Lake Komořany, Czech Republic
• S14-P-06 Charline Giguet-Covex Lake sediment DNA barcoding: a new tool to reconstruct past human activities and plant cover?
• S14-P-07 Jane Reed Palaeoecological reflections on biodiversity, whole-ecosystem shifts and proxy response: ancient lakes of the circum-Mediterranean
• S14-P-08 Helen Roe Examining benthic community response to road salt contamination in lakes: insights from a modern Arcellacea (testate lobose amoebae) dataset from southern Ontario, Canada
• S14-P-09 Isabel Bishop Assessing the changing status of slender naiad (Najas flexilis) in Scottish mesotrophic lochs using the sediment record: implications for conservation
• S14-P-10 Jill McColl Climate variability of the last 1,500 years in the NW Pacific: High-resolution, multi-biomarker records from lake sediments
• S14-P-11 Liisa Nevalainen Functional diversity of Cladocera attributes to lake deterioration ‒ A paleolimnological perspective
• S14-P-12 Nicki Whitehouse Exploring fossil assemblages from modern woodland ponds; implications for catchment processes and biodiversity
• S14-P-13 Petra Houfková Multi-proxy paleoecological study of the profile PK-1-C from the former Komorany Lake, Czech Republic
• S14-P-14 Patrick Rioual Changes in diatom biodiversity over the past 20,000 years as recorded in the varved sediments of Lake Sihailongwan (northeastern China)
• S14-P-15 Sergi Pla-Rabes Assessing microbial diversity using recent lake sediments and estimations of spatiotemporal diversity
• S14-P-16 Teresa Vegas Mid-Late Holocene environmental changes based on multiproxy records from lake sediments of Laguna Encantada, in the Neotropical Gran Sabana (Venezuelan Guayana)
• S14-P-17 Finn Viehberg Lake Iznik (W Turkey) – a continuous ostracod record of 40.000 years. Palaeoecology – Geochemistry – Shell morphology