1. North America Cold Biomes David LeBlanc Ed White

2. Arctic Tundra David LeBlanc

3. Gates of the Arctic National Park, Brooks Range, Alaska. Dominant plants are low-lying shrubs, grasses, and forbs with scattered stunted trees. www.bsu.edu/biology/leblanc Anuktuvuk Pass, Brooks Range, Alaska. Further north no trees at all, just low- lying shrubs, grasses and forbs. 68o 03 42.98 N, 151o 58 12.81 W Note: This is an example of an image that displays characteristics of dominant plant species. Note: This is an example of an image that displays landscape scale characteristics.

4. Arctic Tundra: Climate Short, cool frost-free growing season limits Pnet and growth of trees. Short, cool frost-free growing season limits Pnet and growth of trees. Extreme, cold winters. Extreme, cold winters. Low-lying shrubs, grasses, forbs dominate b/c they are protected under snow during winter. Low-lying shrubs, grasses, forbs dominate b/c they are protected under snow during winter. Trees not present b/c little or no growing season to produce wood and they cannot survive harsh winter conditions. Trees not present b/c little or no growing season to produce wood and they cannot survive harsh winter conditions.

5. Climate Change: Warmer Only Increased Temperature but w/ same Precipitation Increased Temperature but w/ same Precipitation Winters would be less severe, BUT entire growing season would be too dry to support plant growth Winters would be less severe, BUT entire growing season would be too dry to support plant growth Vegetation becomes Cold Desert. Vegetation becomes Cold Desert.

6. Climate Change: Warmer & Wetter Increased Temperature AND Precipitation Increased Temperature AND Precipitation Winters less severe Winters less severe Growing season warmer & longer but precipitation adequate only at beginning and end, droughts in some years. Growing season warmer & longer but precipitation adequate only at beginning and end, droughts in some years. w/ short growing season vegetation remains tundra or becomes sparse, stunted boreal forest. w/ short growing season vegetation remains tundra or becomes sparse, stunted boreal forest.

7. Boreal Forest Ed White

8. Banff National Park, Alberta, Canada. Dominant plants are evergreen trees. www.bsu.edu/biology/leblanc Chutes-des-Passes, Lac St. John, Quebec. Boreal forest dominated by evergreen trees (spruce and fir). 49o 50 49.70 N, 71o 11 42.39 W

9. Boreal Forest Climate Short, cool frost-free growing season limits Pnet Short, cool frost-free growing season limits Pnet Long, cold winters. Long, cold winters. No dry months; fire unlikely. No dry months; fire unlikely. Evergreen conifer trees able to extend growing season by photosynthesizing on warm days in Spring and Fall. Evergreen conifer trees able to extend growing season by photosynthesizing on warm days in Spring and Fall. Evergreen conifer foliage better able to retain heat during cool growing season, increasing Pnet.. Evergreen conifer foliage better able to retain heat during cool growing season, increasing Pnet..

10. Climate Change: Warmer Only Increased Temperature but w/ same Precipitation Increased Temperature but w/ same Precipitation Winters would be less severe and frost-free growing season longer. Winters would be less severe and frost-free growing season longer. Precipitation probably adequate to support growth during growing season, but droughts and fire may become more frequent Precipitation probably adequate to support growth during growing season, but droughts and fire may become more frequent Vegetation may shift to Temperate Deciduous Forest Vegetation may shift to Temperate Deciduous Forest

11. Climate Change: Warmer & Wetter Increased Temperature AND Precipitation Increased Temperature AND Precipitation Winters less severe Winters less severe Growing season warmer and longer with much precipitation and no droughts. Growing season warmer and longer with much precipitation and no droughts. Vegetation becomes Temperate Deciduous Forest. Vegetation becomes Temperate Deciduous Forest.

12. Climate Change Summary In tundra, cold temperature becomes less limiting, but drought stress increases; vegetation shifts from cold-limited to drought-limited cold desert. In tundra, cold temperature becomes less limiting, but drought stress increases; vegetation shifts from cold-limited to drought-limited cold desert. In boreal forest, cold temperature becomes less limiting and growing season expands. W/ adequate water availability vegetation will shift from evergreen trees to temperate deciduous trees. In boreal forest, cold temperature becomes less limiting and growing season expands. W/ adequate water availability vegetation will shift from evergreen trees to temperate deciduous trees.