Impact of permafrost thaw on vegetation transition and community composition

Project keywords: Forest-wetland mosaic; permafrost degradation; species richness; vegetation distribution

Name of project lead: Jennifer Baltzer

Project team/partners: For each collaborator please specify: Team member name, role, organization and contact information
J. Baltzer (WLU; PI), W. Quinton (WLU; collaborator), M. Fafard (WLU; MSc student)

Status: In progress

Location: Scotty Creek (61°18’N, 121°18’W)

Year and month project started: May 2012

Anticipated completion year of project? 2013

Executive year of project (example, year 1 or 2 or 3…) 2

Brief project description: (objectives and rationale)
Background: Northern boreal forests are one of the systems most sensitive to climate change. Of particular interest are the areas underlain by discontinuous permafrost; permafrost aggradation and degradation processes are thought typically to be in balance, but warming may be shifting this balance towards a regime of degradation. Scotty Creek is characterized by discontinuous permafrost and the edges of permafrost plateaus are degrading rapidly. Such dramatic changes cause increase the hydrological connectivity with potentially large implications for resident vegetation communities given the specificity of many plant species for particular water chemistry conditions.

Objectives: To quantify species composition and abundance in dominant wetland types (collapse scar bogs, poor fens, rich fens) and assess how increasing hydrological connectivity due to permafrost thaw is affecting these communities.

Methods:

Fully isolated (surrounded by permafrost), ephemerally connected, and fully connected wetlands of the three abovementioned types were selected based on aerial images. In each selected wetland, five quadrats were established to span the environmental conditions in the wetland. Within each of these quadrats lichen, vascular and non-vascular plant species were identified and the frequency/cover quantified. At each quadrat, the following abiotic factors were also measured: water table depth, soil temperature and moisture, soil/water samples for nutrient and pH measurement, dissolved oxygen, saturated soil moisture content, and bulk density. Measuring response of vegetation the changing hydrology of the system will be an important first step in understanding the rapid changes facing these systems.

Significance of the results (rationale): / project linkages

What are the key contributions to science/our knowledge base of northern environments

This will be the first attempt, to our knowledge to quantify the impact of permafrost degradation on community composition thus will advance our understanding of the implication of this warming related process from a biodiversity perspective

What are the key contributions to cumulative effects monitoring in the NWT?

Understanding the impacts of permafrost degradation on vegetation communities is a critical first step in enhancing our knowledge of cumulative impacts of direct and indirect anthropogenic influences in forest-wetland mosaics representative of the zone of discontinuous permafrost.

What is the relevance to decision-makers?

Because permafrost provides the physical boundaries segregating different wetland types in the southern part of the NWT, there is the distinct possibility that loss of permafrost will result in homogenization of wetland types and a corresponding homogenization of the flora. Such potential for widespread change in biodiversity should be of concern to decision makers.

Which decision-makers will likely be impacted by / interested in results?

ENR managers, community leaders

What is the relevance to communities?

Loss of biodiversity and/or homogenization of landcover types will ultimately impact ecosystem function and wildlife. Such changes will be of concern and interest to northern communities. Furthermore, these plants have a range of traditional uses and with a changing landscape the location and extent of populations of these species can be expected to change.

What are the project milestones? (including beginning date and anticipated end-date)

January 2012: Site selection based on temporal sequence of aerial images (Complete) June-August 2012: Field work (Complete)
September 2012-June 2013: Data analysis and MSc thesis preparation (in progress)
February 2013: Completion of herbarium vouchers and submission of these to the GNWT virtual herbarium and the WLU Herbarium’s Northern Plant collection (Complete)

July-August 2012: Manuscript preparation (in progress)
On-going dissemination of findings to the NWT and scientific community.

Key deliverables and reporting: Link to needs of NWT

1. The proposed work will result in 2 peer reviewed publications and presentations at international conferences

2. The proposed research will be reported to the Science Committee and appropriate GNWT agencies in the form of a manuscript/thesis/report

3. The plant collections will contribute to the growing Virtual Herbarium supported by the GNWT

 

Engagement, training and capacity building

An ideal opportunity for engagement would be bringing a community member with knowledge on the uses of different plant species to the study site to help link the changes that Melissa is documenting with traditional use information.

At the Scotty Creek site, we have a good working relationship with a number of communities, meeting regularly with them and keeping them informed and engaged in work at the site.

 

Links to WSIPlan and NWT Science Agenda

Water stewardship strategy keys to success
1.1H Collaboratively develop and implement an approach that provides for effective use of traditional, local and western scientific knowledge in water stewardship decision-making processes. 1 – With collaborative input from traditional, local and western scientific knowledge holders, develop an effective approach to inform water stewardship decisions. 2 – design effective tools to improve decision-making.

Develop and implement collaborative ecosystem-based research and monitoring programs. 2- develop collaborative partnerships that can enhance ecosystem-based water stewardship in the NWT.

Develop and implement collaborative research and monitoring programs for environmental stressors that can contribute to cumulative effects on NWT watersheds. 3- implement cumulative effects research and monitoring programs.

Key project tasks for next year (work plan pieces – research)

Melissa will attend training workshop to facilitate enhanced analysis of the dataset

Complete thesis and associated manuscripts

Present research at international meeting

Key project tasks for next year (work plan pieces – engagement, training and capacity building)

Plain language presentations at community meetings in Fort Simpson, Jean Marie, and/or Trout Lake with demonstration material showing the utility of the tree ring and peat core records for assessing and predicting change

Published Papers