1. Chapter 6 Communities, Formations, and Biomes

2. Mediterranean Biome Winter wet, summer dry Warm summers, mild winters Found in conjunction with cold ocean currents Valley forest, open woodlands, shrublands, grasslands California – chaparral – oak (Quercus spp) Chile – matorral – Northfagus obliqua and Acacia South Africa – fynbos Australia - eucalyptus Europe – maquis – Pines (Pinus spp), Cedars (Cedrus spp), Fir (Abies spp)

3. Vegetation dependent on long summer drought, fire, and low soil nutrients Annuals more common than perennials Drought strategies (avoiders) –Black sage (Salvia mellifera) loses all but outer leaves in summer –Shrubs – dimorphism –California valley oak (Quercus lobata) – deep tap roots –Low soil nutrients makes deciduousness impractical Mediterranean Biome

4. Fire-tolerant species Scarification, serotinous cones, thick bark, resprouting Invasives from Australia: melaleuca, eucalyptus Mediterranean Biome

6. Temperate Grassland North America – prairie South America – pampas Eurasia – steppe South Africa – grassveld Variable temperature and rainfall Fertile soils 20% herbs, 80% grasses on grasslands Trees along waterways

7. Shortgrass – arid regions –Shallow, extensive root system –1 foot tall Tallgrass – wetter regions –Deep roots to access water table –6 feet tall –1% remains Fires common Invasive annual grasses Temperate Grassland

8. Shortgrass prairie (below) Tallgrass prairie (right)

9. Temperate Forest Variable temperatures and rainfall In the Southern Hemisphere, evergreens In the Northern Hemisphere, deciduous General structure: canopy, subcanopy, herb layer Biodiversity dependent upon glacial history Deciduous forest increasing as farms abandoned – second-growth forest

10. Temperate Rainforest High rainfall, mild temperatures, close to oceans Moisture from fog and orographic lifting Large, long-lived, evergreen trees Redwoods, Douglas fir Lower diversity than temperate deciduous forest and tropical rainforest

12. Coniferous Boreal and Montane Forest Northern Hemisphere Pine, Spruce (Picea spp.), and Fir in North America and Europe Bristlecone pine (Pinus aristata) Larch (Larix spp) in Asia Krummholtz – high elevation shrublands Little understory growth Fire-tolerant plants

13. Bristlecone pine krummholtz (above) Boreal forest - Spruce (below)

14. Geography of Biomes

15. Tundra Biome Found beyond treeline in the Arctic (Arctic Tundra) and in high mountians (alpine tundra) Variable temperatures and rainfall Lower elevations and latitudes: willow (Salix spp.), shrub birch (Betula nana), alder (Alnus spp.), sedges, grasses, herbs, and mosses – low arctic tundra

16. Tundra Biome High arctic tundra (polar desert) – higher elevations and latitudes – arctic willow (Salix arctica) and heliotropic flowering plants Perennials Low biodiversity and biomass With the exception of crowberry (Empetrum nigrum), arctic and southern hemisphere alpine tundra have no similar species

17. Tundra Biome Threats: –Resource extraction –Mining –Snowmobiles –Global warming Arctic willow crowberry