As each individual plant species abides by its own physical and physiological constraints and interacts with other species in a search for suitable habitats, vegetation communities develop. Sometimes pairs of species and species groups take a liking to one another. The conditions they require may be the same, but perhaps they don’t necessarily have to compete. A larger shrub may provide too much shade for a sun-loving plant, but for one that prefers a moister, cooler environment, the shade may be just the environment it was looking for.
Plant communities are complex, and exist across the landscape on many different spatial scales. For the purposes of this project, where our focus is using repeat photos to investigate land cover change, we will talk about vegetation patterns only at a very large scale – ecoregions. However, while browsing photo pairs, be on the lookout for reference to smaller scale plant communities in the description. See if you can pick out relevant boundaries between plant communities and imagine how the physical conditions may change across that zone.
An ecoregion is an area of comparable geography and biota (or life forms). It may contain areas of similar elevation, aspect, weather patterns, and vegetation. There are five ecoregions present within the boundaries of Denali National Park and Preserve as classified by Mark Clark and Michael Duffy in their 2006 soil survey (download the report – 5.5 MB). Each ecoregion has dominant vegetation communities and patterns of distribution that create the vegetation mosaic which influences wildlife movements, species diversity, and response to global climate change. Explore the ecoregions of Denali and help orient yourself to the vegetation patterns you may see in the photo pairs.
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