BC Journal of Ecosystems and Management
The Journal of Ecosystems and Management (JEM) is a peer-reviewed electronic journal covering natural resource and ecosystem management issues relevant to British Columbia. In addition to scientific articles, JEM provides a forum for commentary on current natural resource challenges. JEM’s broad readership includes natural resource practitioners, professionals, policymakers and researchers. The Journal extends research results, indigenous knowledge, management applications, socio-economic analyses and scholarly opinions. JEM is an open-source journal, freely available to the public at www.jem-online.org .
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Arboreal Squirrel Abundance in Response to a Gradient of Mountain Pine Beetle Attack in Sub-boreal Forests
To assist in evaluating habitat retention options, the abundance of northern flying squirrels (Glaucomys sabrinus) and North American red squirrels (Tamiasciurus hudsonicus) wer examined in 2005 and again in 2010 across a gradient of mountain pine beetle (Dendroctonus ponderosae) attack intensity in sub-boreal forests of west-central British Columbia. Among 30, 16-ha live-trapping grids, estimated mean abundance of both species increased non-linearly with remaining basal area of live overstorey (live trees ≥ 7.5 cm diameter at 1.3 m height). A weak (most likely positive but possibly negative) additional response of flying squirrels to dead overstorey (on average 1 m2/ha dead ≈ +0.11 m2/ha live basal area) was evident. The basal area of live spruce-fir (Picea spp., Abies spp.) overstorey, understorey tree density, and tree diameter covariates did not have substantive additional effects on estimated squirrel abundance. Whereas survey year affected overall abundance, it did not change the relationship with habitat attributes. The results suggest that dead lodgepole pine (Pinus contorta) has low habitat value for arboreal squirrels and thus is of lower impact on squirrels if salvage-harvested; however, retention or re-growth of sufficient live overstorey is necessary to maintain or recover squirrel abundance. The basal area of
live overstorey appears a simple yet useful management metric for prioritizing habitat
value, at least as indicated by relative abundance for squirrels in beetle-affected forests.
Greenhouse gas emissions from cattle have been increasingly recognized as an important anthropogenic source. We investigated the impact of cattle ranching on these emissions in British Columbia in order to determine the overall carbon footprint. The grazing activity within the Lac du Bois grasslands of British Columbia was examined, with emphasis on identifying point sources and removals of greenhouse gas emissions from cattle ranching. Enteric methane emissions were empirically measured at two elevation gradients in the spring and fall of 2010. Cattle emitted on average 370 L CH4 per day; these measurements on native grasslands are comparable to work on tame pastures. A life cycle analysis was conducted with a validated HOLOS model based on empirical measurements. The following grassland improvement strategies were evaluated: reducing stocking density; and reseeding/interseeding grass and legumes with and without synthetic fertilizer additions. Reseeding was the most effective at reducing the carbon footprint of cattle ranching on the Lac du Bois grasslands. Reseeding initiatives could theoretically result in soil carbon sequestration rates of 2.12 Mg CO2 equivalent per hectare. A combination of reductions and removals should be implemented in the future to reduce the overall carbon footprint of cattle ranching in British Columbia.
Conservation of species at risk requires an understanding of resource-selection patterns and habitat distribution. We used 1,795 radio-telemetry locations from 55 study animals to model resource selection for an endangered population of American badger (Taxidea taxus jeffersonii, eastern population) in the Rocky Mountain Trench of British Columbia. The badgers were associated with low elevations, shallow slopes, high solar radiation, and low crown closure. They selected higher elevations only on sites with shallow slopes or high solar radiation. Compared to mesic low-elevation forests, badgers selected locations where the climax ecoclass was riparian forest or very open low-elevation forest. In comparison to Douglas-fir stands, badgers selected clearings, moist forest, and open range. They avoided lodgepole pine stands, western larch stands, and wet areas. Relative to the Brunisol soil order, they avoided Podzolic – Luvisolic and Regosolic-Gleysolic orders. Compared to Morainal soil parent material, the badgers avoided colluvial, rock, aeolian, and anthropogenic and selected for glaciolacustrine parent material. Results were consistent both with expectations from other provincial studies and with cover types used by Columbian ground squirrels (Spermophilus columbianus), which are their main prey. Our model provides a spatially explicit tool to prioritize areas for restoration or critical habitat designation. Reduction of crown closure would benefit badgers, and would probably be the most advantageous on Brunisolic or Chernozemic soils and glaciolacustrine parent material.
Bioenergy is a viable solution to BC's Wildland-Urban Interface fuels problem; however, a number of policy changes are needed first
We have an increasing wildfire risk to communities of the province that is not being effectively addressed by the current hazard reduction program. Existing planning and remediation efforts are a small fraction of what is required given the march of climate change, the steady accumulation of forest fuels in the WUI and the large number of affected communities. The greatest barrier to an adequate response is the high cost of initial and recurring treatments, dependent primarily on tax funds from senior governments, and the lack of a policy framework that makes it possible to earn offsetting revenues from remedial work. Continuing on this trajectory will bring the predictable results of increasingly frequent and increasingly severe interface fires. A solution to this impasse is a major departure from current policy and practice; it is an attempt to turn an economic barrier into an economic advantage by converting a fuel surplus from a costly burden to a commercially valuable energy source. Because the proposal affects the legislated jurisdictions of communities, the tenure rights of existing industry, the encouragement of a new energy industry, the revision of silvicultural requirements, the linked use of merchantable timber and lower value biomass, expanding the carbon offset regime and sensitivity to international timber pricing agreements it is a formidable challenge to our current forest administration. Such a bold transformation likely cannot be approached piecemeal nor can it be applied province-wide without practical trial.
An Evaluation of the Main Factors Affecting Yield Differences Between Single- and Mixed-Species Stands
The native grasslands and associated dry woodland ecosystems of the BC Interior are an important economic, biodiversity, and recreational resource. They also form an integral part of our cultural fabric, contributing to a sense of place-identity for many British Columbians. All the ecosystems of the Province will experience fundamental shifts as a result of climate change, but given the unique and complex nature of the Bunchgrass (BG), Ponderosa Pine (PP) and the dry phases of the Interior Douglas-fir (IDF) Biogeoclimatic (BGC) zones, they are deserving of a separate treatment. This discussion paper is not intended as a definitive review, but rather to initiate dialogue on an issue that is significant to both the livestock and conservation sectors.
this analysis used a large data set, our inability to correlate disturbance with site characteristics and the differences between monitoring methods points to the need for common terms and comparable guidelines for soil disturbance monitoring.
Crown land is unique to the Commonwealth and better represented in British Columbia than anywhere else in the Commonwealth (95% of the land base). Through tradition and common law, British Columbians have come to define Crown lands as publicly owned lands that belong to all residents and to expect governments to shepherd them for the benefit of all. Social licence to operate on this land requires approval from the local community and other stakeholders. The concept of Crown land makes every British Columbian a potential stakeholder and has led to more drama and noise around social licence than occurs elsewhere. The four main reasons for failure in past applications for social licence have been a lack of respect, assuming economics is a sufficient framework, appearing to bully, and hiding or obscuring information deemed relevant. Recent events in the province suggest the provincial and federal governments, and some companies, have learned little from past failures. Energy development faces particular challenges because location counts and impacts are both intrusive and extensive, but the errors described here are avoidable. W. Edwards Deming reputedly observed, “Learning is not compulsory… neither is survival.” Some companies have learned.
The topic is addressed under six headings: (1) Whose land is it?; (2) What the public has said; (3) Defining social licence; (4) Lessons from exploring social licence; (5) Lessons and energy development; and (6) What’s next?
Understanding Occupational Health and Safety Culture for BC Aboriginal Fire Crews and Emergency Service Personnel: Research Update
Use of airborne gamma radiometrics to infer soil properties for a forested area in British Columbia, Canada
We obtained radiometric data from a public-domain archive maintained by Natural Resources Canada and processed them to produce a ternary image for a portion of the Cariboo region. A field program was used to evaluate what information could be reliably inferred from the available data. This initial investigation confirmed that the radiometrics for this area exhibited consistent and useful patterns to interpret the lithology, mineralogy, depth, and moisture status of the surficial materials. Different colour patterns in the ternary image correlated well with different compositions of the various tills. We noted a clear association between higher values of radioactive emission and more recently deposited aeolian, alluvial, and glaciofluvial sediments that contained higher concentrations of relatively unweathered minerals. We observed a clear pattern of lower emission from wetlands and areas of wet soil. Airborne radiometrics, even at 500-m line spacing, provided invaluable and precise information—not otherwise obtainable—for mapping or modelling spatial variation in properties of the surficial material within the forested study area in British Columbia. We recommend further investigations to develop operational procedures for the use of such data in mapping surficial materials.
Rapid climate change is predicted for British Columbia’s Inland Temperate Rainforest (ITR), a globally unique ecosystem. Lichens, which may serve as effective biomonitors of ecosystem health, have been proposed for use as climate change indicators for a variety of ecosystems globally. This research presents a climate biomonitoring protocol using arboreal macrolichen communities in the inland rainforest in British Columbia. We report our initial findings of 39 lichen taxa, including a number of rare species and cyanolichens, which may be especially sensitive to climate. Comparisons of these data with future measurements will provide an indication of how the inland rainforest may be responding to climate change.