The 26 km2 lava plain left by the Tseax Volcano in the Nass Valley is an impressive central feature of the Nisga’a Lava Beds Memorial Provincial Park north of Terrace, B.C. The volcanic eruption that took place sometime in the 1700s and its impacts are central to the history of the Nisga’a First Nation. The current lava landscape supports a wide variety of vegetation, ranging from largely bare rock and thick blankets of lichens and mosses, to areas of closed forest cover dominated by mature lodgepole pine and cottonwood, prompting the question, “Why are there such pronounced differences in ecosystem development more than two centuries after a single historical disturbance?” Field research undertaken in 2018 and 2019 revealed significant effects of substrate differences, as expected, but also a pronounced legacy of recent disturbance events. A distinctive climate on the lava plain, combined with human activity, has resulted in recurrent wildfires that repeatedly reset the pattern of succession there. Conversely, other disturbances such as flooding and road construction have led to silt deposition that has promoted the establishment of trees and other vascular plants. As extreme weather leading to fires and floods is on the increase, future vegetation development on the lava beds can be expected to be set back in some places and accelerated elsewhere. This complexity challenges textbook descriptions of linear ecological succession and foretells an uncertain future in a changing climate.

The Natural Resources & Environmental Studies Institute (NRESi) at UNBC hosts a weekly lecture series at the Prince George campus. Anyone from the university or wider community with interest in the topic area is welcome to attend. Go to http://www.unbc.ca/nres-institute/colloquium-webcasts to view the presentation remotely.

Past NRESi colloquium presentations and special lectures can be viewed on our video archive, available here.

Please Note: NRESi colloquium presentations this semester will be available to attend both in-person as well as online. However, those wishing to attend in-person must be partially (before Oct 24th) or fully-vaccinated (after October 24th) and wear a mask as per Provincial Health Officer (PHO) orders and University policy. Thank you for your understanding.