Vegetation Succession and Environmental Conditions following Catastrophic Lake Drainage in Old Crow Flats, Yukon
Increases in the frequency and magnitude of disturbances associated with the thawing of ice-rich permafrost highlight the need to understand long-term vegetation succession in permafrost environments. This study uses field sampling and remote sensing to explore vegetation development and soil condit...
| Published in: | ARCTIC |
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| Main Author: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
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Arctic
2017
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| Online Access: | https://doi.org/10.14430/arctic4646 https://dspace.library.uvic.ca//handle/1828/9940 |
| Summary: | Increases in the frequency and magnitude of disturbances associated with the thawing of ice-rich permafrost highlight the need to understand long-term vegetation succession in permafrost environments. This study uses field sampling and remote sensing to explore vegetation development and soil conditions following catastrophic lake drainage in Old Crow Flats (OCF). The data presented show that vegetation on drained lake basins in OCF is characterized by two distinct assemblages: tall willow stands and sedge swards. Field sampling indicates that these alternative successional trajectories result from variation in soil moisture following drainage. Increased willow mortality on older drained basins suggests that intraspecific competition drives self-thinning in shrub thickets. This finding, combined with data from paleoecological studies and contemporary vegetation in OCF, suggests that willow stands on drained lake basins are seral communities. These results also indicate that the increase in number of catastrophic drainages that occurred between 1972 and 2010 will alter regional vegetation in ways that affect wildlife habitat, permafrost conditions, and local hydrology. This research was supported by the Government of Canada International Polar Year Program, the Natural Sciences and Engineering Research Council of Canada, and the Canada Foundation for Innovation. Erika Tizya provided excellent assistance in the field in the summers of 2008 and 2009. Tracy Bruce, Sonja Foss, Sarah Gergel, Shel Graupe, Jim Hawkings, Kendra Holt, Pascale Roy-Leveillee, and Stan Njootli Sr. provided valuable assistance with planning and logistics. I would also like to thank the Vuntut Gwitch'in land users who contributed to the Yeendoo Nanh Nakhweenjit K'at r'ahanaht yaa project and the Vuntut Gwitchin First Nation for supporting this initiative. Faculty Reviewed |
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