In the wilderness of a remote South Island lake, Kendrick Brown leans over the boatB次元官网网址檚 edge and drives a hollow tube into the soft lakebed sediment below.
What he pulls out, one metre at a time, is a historical timeline embedded in layers of organic and non-organic matter. It tells him about the past, and helps paint a picture of whatB次元官网网址檚 to come.
B次元官网网址淭heyB次元官网网址檙e natureB次元官网网址檚 archives: stratigraphic sequences in the mud that read like pages in a book,B次元官网网址� says Brown, a research scientist with the Canadian Forest Service.
B次元官网网址淏asically, the same mud that you sink your toes into during a summer swim is the cover of the book, a recording of history of the region based on the matter that has settled into the lake floor.B次元官网网址�
BrownB次元官网网址檚 project team is based out of the Pacific Forestry Centre in Saanich and includes research technician Nicholas Conder, Nicholas Hebda, and University of Victoria co-op student Kiera Smith. While the focus is on the past, the results can help inform about the future.
The teamB次元官网网址檚 current focus is on sediment cores collected from the Greater Victoria Water Supply Area, namely from Begbie Lake and the Sooke Lake Reservoir.
Brown is examining records from these lakes because paleoclimate indicators suggest the past time interval known as the early Holocene (11,700-7,000 years ago) was warmer and drier compared to present-day.
Scientists hope the data may serve as a first-order reference to what future conditions may be like if induced by climate change.
There are models suggesting temperatures in southern B.C. may increase 2-3 degrees C by 2100, he said.
Extracting pollen and charcoal fragments from the lake sediment cores allows the team to assess how vegetation and fire changed through time,B次元官网网址� Brown said.
B次元官网网址淲e now have a sense of how the fire regime has changed in the Sooke Lake Reservoir catchment throughout the Holocene (period) and will be informing the CRD about the natural variability of fire events within the water supply catchment,B次元官网网址� he said. B次元官网网址淲eB次元官网网址檙e now working to understand how vegetation in the catchment has changed through time, the signal of which is contained in abundant fossil pollen grains in the sediment.B次元官网网址�
The forestry scientists have teamed up with the CRD because the regional body needs to know about fire risk to water supply, Brown said.
B次元官网网址淲eB次元官网网址檙e using natureB次元官网网址檚 archives to learn how the land responded to past changes in climate and identifying past periods that might be analogues for the future,B次元官网网址� he said.
Are future generations of South Islanders destined to live in a fire-prone region? Not quite, but fire disturbance may increase in the future.
B次元官网网址淲e need to plan for and protect against this risk. While fire is not a common form of disturbance today, it was more prevalent in the past,B次元官网网址� Brown said.
That plan is still a few years off. The team is hoping to produce an initial report of findings by the end of 2016.
- BrownB次元官网网址檚 team use a Livingstone corer to reach lake sediment depths of up to 10 metres, sometimes more. The deeper the corer goes, the older the sediment.
reporter@saanichnews.com
