1. Biomes

2. Outline Tundra Taiga Temperate Deciduous Forest Grassland Desert Mountain and Coastal Forest Tropical Rain Forest

4. Tundra Primarily above the arctic circle. Appears treeless. Precipitation averages < 25 cm annually.  Permafrost holds water at or near the surface.  Short growing season of 2-3 months.  High temperatures range to about 27 o C.  Very fragile.

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6. Taiga Northern Conifer (Boreal) Forest Adjacent and south of arctic tundra. Dominated by Spruce, Fir, and Pine. Few Annuals. Temperate Range -50 o C to 30 o C. Annual precipitation ranges from 25-100 cm.  Most occurs in the summer.

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8. Temperate Deciduous Forest Composed of mostly broad-leaved species that shed their leaves during the fall, and remain dormant during short winter days. Most occur in large continental masses in Northern Hemisphere. Temperatures range from 4 o C to 20 o C. Annual precipitation ranges from 50-165 cm.  Mostly occurs in summer During summer, solid canopy keeps direct sunlight from reaching the forest floor.

9. Grassland Found in interior of continental masses. Annual precipitation ranges from 25-100 cm. Temperatures range from -45 o C to 45 o C. North American grasslands (prairies) grew on fertile soils supporting large herds of migratory grazing buffalo.  Mediterranean climate receives most precipitation in the winter, thus grasses do not grow as tall as those of Midwestern prairies.

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11. Desert Many of the world’s major deserts are located at 30 o N and 30 o S latitude. Most receive < 12.5 cm annual precipitation. Low humidity. Wide daily temperature fluctuations.  15 o C - 35 o C on a hot summer day. Some plants exhibit CAM photosynthesis. Other plant adaptations include thick cuticles, water-storage tissues in stems and leaves, and thick leaves and / or reduced in size.

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13. Mountain and Coastal Forest Coniferous forests occupy vast areas of the Pacific Northwest as well as portions of the Rocky Mountains and the Sierra Nevada. Conspicuous altitudinal zonation of species. Relatively dry summers.  Frequent forest fire regime. - Fire-adaptations.  Bark  Cones

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15. Tropical Rain Forest Annual precipitation ranges from 200-400 cm. Temperatures range between 25 o C and 35 o C. No dry season. Humidity usually > 80%. Dominated by broad-leaved evergreen trees. Shallow root systems. Dense multi-layered canopy. Poor soils  Nutrients either uptaken by plants or leached by heavy rainfall.

16. Review Tundra Taiga Temperate Deciduous Forest Grassland Desert Mountain and Coastal Forest Tropical Rain Forest

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