Freeing the Elwha (Aspect Treeline Climate)
OverviewTrees play an important role in salmon habitat. How can an understanding of climate, aspect, soil moisture, and treeline add to our understanding of healthy river restoration?
This lesson focuses on the factors that determine the location of the treeline in different locations in the world. The elevation of treeline is affected by the combined effects of snowpack depth, minimum winter temperatures, aspect, and soil moisture conditions. Treeline varies by latitude, but is also affected by whether it is an arid, temperate, or tropical climate. In addition, in arid regions, aspect and elevation affects soil moisture conditions and determines where the transition from desert to forest occurs on sky islands. In addition, human impacts such as grazing and fires can impact the elevation of treeline.
- Treeline- The elevation in a mountainous region above which trees do not grow. The northern or southern latitude beyond which trees do not grow.
- Sky Island- Mountains in ranges isolated by valleys in which other ecosystems are located. As a result, the mountain ecosystems are isolated from each other, and species can develop in parallel, as on island groups such as the Galápagos Islands.
- Aspect - position facing or commanding a given direction; exposure
- Snowpack- The seasonal accumulation of snow in the winter that is available for melting in the spring and summer.
- Lesson 8- Aspect, Treeline, and Climate.pptx
- Predicting Treeline student edition.pdf
- Predicting Treeline teacher key.pdf
- Reflection Journal pages (Printable handout)
- Vocabulary Notes (Printable Handout)
Review the Essential Question. Introduce the guiding Question.
Students should take a few minutes to respond to the first reflection prompts. Discuss their answers and any questions they've generated.
Hand out the second Reflection Journal Page. Give students time for a final reflection on the lesson.