BIOMES An Introduction to the Biomes of the World Definition of a Biome Terrestrial referring to land Climatically controlled sets of ecosystems Characterized by distinct vegetation 1
In a Biome There is an exchange of: Air, Water, Nutrients & Biological components, And yes... This includes people Definition of an Ecosystem Major systems within a biome - interacting communities of organisms Involves interaction of living organisms and physical environment The Biomes: Tundra Taiga Temperate Mixed & Coniferous Forests Temperate Deciduous Forests Grasslands Chaparral / Mediterranean Scrub / Mediterranean Chaparral Desert / Desert Scrub Savanna & Deciduous Tropical Forests Rainforests Alpine 2
Distribution of Biomes Results from 3 major factors 1) Global patterns of air circulation Distribution of Biomes Results from 3 major factors 2) Distribution of heat from sun The relative seasonality of different portions of earth 3
Distribution of Biomes Results from 3 major factors 3) Geological factors inc. mountains both heights and orientation 4
Tundra and Its Climate Fragile, cold environment 20% of Earth s surface Winters long, cold dark to 90 F (-70 C) Summers land of the midnight sun to 50 F The Tundra A Northern Hemisphere Phenomenon Permafrost ground permanently frozen Shallow soils poor drainage Tundra Soils Soils low in nutrients Soils are acidic to neutral ph Tundra - Finnish word for barren or treeless 5
Tundra Habitat Upper permafrost thaws in summer soggy environment Marshy, bogs, lakes and streams Multitudes of insects makes habitat for migratory birds Vegetation lichens, mosses, heaths Low annual precipitation - <10 Most moisture held close to ground Taiga A.K.A Northern Coniferous Forest or Boreal Forest or Needle-Leaf Forest Largest biome on planet Across Europe, Asia & North America Taiga and Its Climate Located below Tundra Winters: -65 F to 30 F (-54 C to 1 C) Summers: to 70 F (21 C) Warm, rainy and humid Average precipitation 12 to 33 per year as rain, dew and snow Taiga The Boreal Forest 6
Taiga Habitat Precipitation mostly as summer rainfall Permafrost in higher latitudes Less than 3 of soil Soils highly acidic, low in nutrients Vegetation mostly coniferous (conifers cone bearing plants) Taiga Habitat (cont.) Coniferous plants Spruce (Picea), Larch (Larix), Fir (Abies), Pine (Pinus) Deciduous trees & shrubs Poplars (Populus), Willows, (Salix), Alders (Alnus), Birch (Betula) Various perennials, mosses and lichens No annual plants Taiga Pond in Ontario, Canada 7
Zones between Temperate Deciduous Forests and Deserts Generally occurs over large portions of continental interiors Grasslands Grasslands and Its Climate Precipitation as much as 40 per year Precipitation types and amounts governed by adjacent Biomes Temperatures range from 40 F to over 80 F Grasslands of China Grasslands Habitat Tall Grass Prairies most productive temperate farming lands Lacks trees except in riparian areas Disturbed grasslands can evolve into Deserts or Forests 8
Grasslands Habitat (cont.) Native vegetation bunch grasses, sod-forming grasses perennials and no annuals Where Biomes converge a wide variety of plant communities are sustained Integration occurs with Temperate Deciduous Forests, Savannas and Rainforests where adjacent Temperate Deciduous Forests Almost entirely in northern hemisphere Regions of warm summers and cold winters North America 38 to 45 N. latitudes Europe & Asia 45 to 60 N. latitudes 9
Temperate Deciduous Forest Climate Precipitation mostly as rainfall 30 to 60 per year Four distinct seasons Low available moisture in winter Deciduous nature of plants a function of water conservation Fall Color Temperate Deciduous Forest Habitat Shallow soils, acidic, low in nutrients Vegetation broadleaf deciduous trees, shrubs & perennials Virtually no annuals due to limited light Annuals cannot store enough nutrients in seed to survive from germination to reproduction 10
Temperate Mixed Deciduous & Coniferous Forests Narrow band between Temperate Deciduous Forests and Taiga Conifers mixed with deciduous plants Winters colder than Temperate Deciduous Forests Precipitation winter rainfall, fog and some snow Temperate Mixed Deciduous & Coniferous Forest Habitat Considered harvestable timber regions Notable species inc.: Coast Redwood Giant Sequoia or Big Tree Douglass Fir Sugar Pine Chaparrals A.K.A Mediterranean or Chaparral or Mediterranean Scrub Characterized by regions along the Mediterranean Sea Chaparral Associated with cool ocean currents 11
Chaparral Locations 30 and 40 north and south latitudes Chaparrals occur in: Central Coastal Chile Southwestern Coastal Africa Southern and Southwestern Australia and Southern California Coastal Sage Scrub Chaparral Climate & Habitat Average annual rainfall: 10 to 20 Winters rarely below 30 F Summers to 100 F Evergreen or summer deciduous plants Short growing season Fire plays an important part Chaparral Climate & Habitat Plant adaptations include: Small foliage Gray foliage Summer- or drought-deciduous Furry foliage Green trunks/branches Thick, resinous or leathery foliage 12
Covers 20% of planet Atmospheric high pressure areas Continental interiors Flanks tropics 30 north and south latitudes towards poles Deserts Desert Climate < 7 rainfall per year Some deserts < 1 Rainfall determined by adjacent Biomes Equatorial sides summer precipitation Polar sides winter precipitation Temperatures from range below freezing to 120 F+ No predictable annual rainfall!!! Desert Habitat Specialized vegetation with various adaptations Plants able to store water or reduce water loss Leathery foliage reduces water loss Plants go deciduous when dry Photosynthesis can occur without leaves 13
Desert Habitat Plant adaptations include: Small foliage Gray or fuzzy foliage Summer- or drought-deciduous Green trunks/branches Thick, resinous or leathery foliage Swollen/expandable trunks Spines Savanna / Deciduous Tropical Forests Grasslands and scattered deciduous and evergreen trees Large variation in temperatures Temperature swings account for seasonal droughts and sparse vegetation 35 to 60 annual rainfall Savanna / Deciduous Tropical Forests Locations Acts as transitional zones Between Tropical Rainforests and Deserts Between Prairies and Temperate Deciduous Forests Between Prairies and Taiga A large Savanna runs along the southern Sahara Desert 14
Savanna / Deciduous Tropical Forests Habitat Mostly perennials Nearly all plants are deciduous Most have small leaves Periodic burning revitalizes Baobab Trees on the Savanna of Madagascar Savanna / Deciduous Tropical Forests Habitat Plant adaptations include: Small foliage Gray foliage / furry foliage Summer- or drought-deciduous Green trunks/branches Thick, resinous or leathery foliage Swollen trunks Spines Tropical Rainforests Region roughly parallels equator Occupies regions 15 to 25 north and south of the equator 15
Tropical Rainforests Climate Excess of 250 annual rainfall Hi relative humidity Distinct monsoon season in some regions Average temperatures 73 F Temperatures range from 64 F to 93 F Monsoon seasonal wind and rain associated with southern Asia Tropical Rainforests Habitat More plant species per acre than other Biomes Trees can exceed 150 Low light on forest floor Tropical Rainforests Habitat Forest Floor Forest divided into stories or horizontal sections Understory lowest levels, forest floor Plants adapted to low light Large, dark green foliage 16
Tropical Rainforests Habitat Lower canopy more light than forest floor filtered light Limited biodiversity Upper canopy higher levels of light Tops of the upper canopy in full sun Highly diverse plant and animal population Upper canopy rich with epiphytes Tropical Rainforests Habitat Epiphytes Epiphytes air plants grow on surfaces of other plants Don t require soil to survive Live attached to rocks or other plants Don t harm host plants Includes ferns, orchids and bromeliads Epiphytes Alpine Regions Mountainous regions world wide Similar to Tundra but drier Above tree line and below permanent snow line Gritty, fast-draining soils low in nutrients 17
Alpine Regions Climate Long winters October to May Short summers June to September Temperatures well below freezing to above 60 F Cold and dry slows decomposition Gritty Alpine Soils Alpine Regions Habitat Few, very specialized plant species Able to withstand cold, dry winds, snow pack, little available water Plants tend to hug the ground Alpine Flora Biome Websites A few websites for Biome research http://www.blueplanetbiomes.org/world_biomes.htm http://www.blueplanetbiomes.org/climate.htm http://www.geo.arizona.edu/antevs/biomes/ 18