Research into the paleoenvironments of western Canada has been ongoing at SFU since 1975, with a focus on climate change, vegetation dynamics, historical plant geography, Quaternary geology and archaeology. The laboratory is housed in the Department of Biological Sciences and is supplied with the usual coring equipment, research microscopes and computers, two fume hoods, basic reference collections for pollen and plant macrofossils, and a large cold-room for storage of cores and samples.

Currently, there are six graduate students (normally 3-4) enrolled in thesis research, working either in the Yukon/Alaska region, or in coastal British Columbia. The Yukon work is based on plant remains and the analysis of fossil chironomid head capsules in lake sediments to test hypotheses of past climatic conditions made from pollen records. Dr. Ian Walker is co-supervising Erin Barley and Lydia Stepanovic in their Master’s programs, guiding their efforts to create transfer functions for temperature using chironomid data. Erin Barley is almost finished her program, and describes her work as follows:

"My research focuses on (1) the development of a chironomid-temperature model for NW Canada and Alaska, and (2) the application of this model to reconstruct temperatures from Antifreeze Pond in SW Yukon. This research is part of a collaborative project aiming to reconstruct past climates in Eastern Beringia, using multiple indicators at multiple sites. I see the first portion of this research as a contribution to the collective set of tools available to paleoecologists for reconstructing past temperatures. This model will be the first chironomid temperature model for Beringia, and other paleoecologists have already expressed an interest in using it for their research. Antifreeze Pond provides an old record (tentative dates suggest it spans the full glacial) with some interesting changes in chironomid assemblages over time. Two of the four zones consist of very unusual assemblages with no modern analogues. While this is a real challenge to interpret, it appears these unusual assemblages are a result of the age and climatic sensitivity of the pond, and both contain valuable information. Qualitative interpretations of the data suggest to me that the chironomids are responding not only to temperature, but also to changing lake depth, which indicates changing moisture regimes."

By contrast, Lydia Stepanovic is just beginning her program, which is also aimed at reconstructing late-Quaternary paleoclimate from eastern Beringia, using chironomids from Birch and Windmill Lakes in Alaska. As this project develops, Lydia expects to be able to compare different paleoclimatic proxies, using the work of others as well as her own, to better understand the climatic evolution of this region. A number of controversies regarding climate, large mammal biodiversity, and the nature of the vegetation cover during glacial conditions are still unresolved for eastern Beringia, and chironomid research is expected to provide important new insights.

Still keeping with the Beringian theme, Grant Zazula has begun his doctoral research in the Yukon in conjunction with glacial geologists at Simon Fraser and at the University of Alberta. Following up on his exciting Master’s work in Edmonton, Grant is going to test the controversial "Mammoth-Steppe" hypothesis for the unglaciated Yukon. He summarizes his project as follows:

"My PhD research is focused on unraveling questions surrounding vegetation and ecosystem dynamics during Pleistocene full-glacial intervals in eastern Beringia. I am working with a multidisciplinary group that is using tephrochronology, paleomagnetics, stratigraphy, and paleoecology within ice-rich loess sequences in central Alaska and Yukon to examine environmental change over the late Cenozoic. I aim to reconstruct the past vegetation cover in the Klondike district near Dawson City, Yukon. Deposits dating to Marine Isoptope Stage (MIS) 6 (ca. 190 - 125 ka BP) and MIS 2 (25-15 ka BP) glacial intervals are exposed here. I am currently analyzing plant macrofossils from frozen middens of Arctic ground squirrels (Spermophilus parryi) which yield exceptionally preserved plant remains that can be identified with high taxonomic precision. These include grasses and sedges that are typically only identified to family level in pollen diagrams.

I also plan to analyze opal phytoliths from paleosols that are developed within frozen loessal sediments. Phytoliths have been underutilized in circumboreal regions, yet are known to provide detailed, local paleoecological data in regions known to have grass and herb-dominated pollen assemblages. I will also analyze phytoliths from plants and soils in extant Beringian tundra and grassland ecosystems that are influenced by loess deposition to try and identify probable vegetation analogues for fossil samples. These data will be used to test the "mammoth-steppe" hypothesis, which suggests that productive steppe vegetation was established in eastern Beringia during Pleistocene glacial intervals, and supported a diverse, now-extinct large mammal community. We hope that his research will provide data to help resolve long-debated questions regarding terrestrial ecosystems of Beringia, especially the identification of genera and species of grasses, sedges, and sage - the taxa that dominate full-glacial pollen assemblages of this region."

The paleoecology of coastal B.C. has been the dominant focus of research in my laboratory. Terri Lacourse, a PhD student in my lab, is nearing completion of her thesis on the late Pleistocene and Holocene paleoecology of the north central coast of BC, with special emphasis on pollen analysis of late-glacial sediments from the Queen Charlotte Islands and continental shelf. Her thesis documents the late-glacial transition from herbaceous tundra to closed forest at a time when the adjacent mainland was still glaciated. This work has major implications for assessing the coastal strip from Alaska and British Columbia as a possible early migration corridor for plants and animals (including humans). She recently published a paper in Quaternary Research on pollen, plant macrofossils, and fossil wood from terrestrial deposits with in-situ conifers from the now submerged continental shelf. Her work will provide a detailed reconstruction of the vegetation that grew on the formerly exposed shelf, and was subsequently "drowned" by rising postglacial sea levels.

Tracy Arsenault will defend her MSc thesis next Spring Semester, based on her paleoecological research in the Coast Mountains of British Columbia. She describes her thesis as a paleoecological study of Holocene sediments at Moraine Bog near Tiedemann glacier. She is using palynology, sedimentology, moraine stratigraphy, and radiocarbon dates from the sediments of Moraine Bog to reconstruct post-glacial environments and to examine the extent, timing and nature of the Tiedemann glacier advance (ca. 3300-1900 ¹⁴C yr BP). The results of these investigations will be used to reconstruct a chronology of Neoglacial climate changes for the central coast of B.C., and to suggest possible climatic forcing mechanisms. Preliminary data suggest that Tiedemann Glacier is the only one in the Coast Mountains that is known to achieve its maximum Holocene extent during the "Tiedemann advance" rather than the Little Ice Age.

A new project was inititated in 2003 by Marian McCoy, who will be conducting her Master’s research in conjunction with Dr. Marlow Pellatt of Parks Canada, as part of a strategy to develop management guidelines for the threatened Garry Oak ecosystems in southwestern B.C. She describes her work as follows:

"Fire suppression and land development have reduced Canada's Garry oak (Quercus garryana) ecosystems (GOEs) to 5% of their former coverage. Conservation and restoration efforts are underway, but little is known about past GOE plant commuities and fire regimes. My research objective is to reconstruct the paleoecological history of two intact GOE sites in BC’s southern Georgia Basin. We will extract 150cm long cores from small lakes adjacent to study sites, and section the cores at 1cm contiguous intervals. This should capture about 1,500 years of data in roughly 10-year sections, depending on the sediment accumulation rate. This timeframe includes pre- and post-European contact periods, and may reveal recent climate changes such as the Little Ice Age and Medieval Warm Period, as well as fire events. I'll analyze macroscopic charcoal fragments (>125µm) as indicators of local fire activity. Variations in fossil pollen are expected to reflect plant community responses to fire and competition from introduced plant species."

Rolf Mathewes will be involved in supervising the above studies, and conducting others as well. Current priorities are collaborative studies using palynology to detect past earthquakes from coastal marsh and lake sediments, and expanding our knowledge of mid-Wisconsin age paleoenvironments from the Queen Charlotte Islands and central British Columbia. My research focus is still on the central coast of B.C., and testing hypotheses about vegetation, climate, and the potential for early colonization of the Americas by a coastal migration route during late glacial time. I am also engaged in studies of paleoclimate in Early Eocene sediments of B.C. using plant macrofossils and pollen. Most of the work in my laboratory has been funded by NSERC grants, with supplementary funding from Forest Renewal B.C., Geological Survey of Canada, Parks Canada, Simon Fraser University, and other sources.

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Note: This article first appeared in CAP Newsletter 26(2):8-10, 2003.