TITLE:
Does Dust from Arctic Mines Affect Caribou Forage?
AUTHORS:
Wenjun Chen, Sylvain G. Leblanc, H. Peter White, Christian Prevost, Brian Milakovic, Christine Rock, Greg Sharam, Harry O’Keefe, Laura Corey, Bruno Croft, Anne Gunn, Sjoerd van der Wielen, Adeline Football, Boyan Tracz, Jody Snortland Pellissey, John Boulanger
KEYWORDS:
Mining, Arctic, Caribou Habitat, Road Dust, PM2.5, Vegetation Cover, Lichen, Soil pH, Dust Deposition
JOURNAL NAME:
Journal of Environmental Protection,
Vol.8 No.3,
March
16,
2017
ABSTRACT: This study explores how dust
from the Ekati Diamond Mine potentially affects the availability and quality of
forage on the seasonal range of the Bathurst caribou herd. Understanding the
effects of dust as a source of disturbance is important because the Bathurst
caribou population has declined by 93% since the middle 1980s and there are
reports that caribou in general may avoid mining projects. There are several
challenges for quantifying dust impacts: 1) Natural variations (e.g.,
topography, natural disturbance, and soil pH) may also impact forage
availability and quality for caribou. To minimize their masking effect, we
stratified survey sites into seven land cover classes and selected the most
populous class (i.e., the dwarf
shrub) for assessing the impact. 2) Within class variation (e.g., the
proportion of area covered by rocks where vascular plants and lichen do not
grow) can further skew the analysis. We eliminated this problem by examining
only the area not covered by rocks. 3) Coarse and fine suspended particulates
have different spatial coverages, chemical compositions, and pH values.
Consequently, their impacts on caribou forage can be different. To distinguish their
impacts, we sampled two areas: transects from the Misery Haul Road that has
been in active use vs. those from a rarely used spur road outside the Misery
Camp. We sampled percent vegetation cover, soil pH, and dust on leaves along
these transects during the summers of 2015 and 2016. Our results indicated that
the amount of dust on
leaves in a zone of ~1000 m from the Misery Haul Road was 3 - 9 times than that
of background sites. The zone of reduced lichen
percent cover was also about 1000 m. In contrast, these road dust-induced
changes in caribou forage were not observed for the dust-free transect from the
spur road.