GLOBAL BIOME PATTERNS

Mediterranean Woodland & Scrub (Chaparral)

• Cs (Mediterranean or dry summer subtropical) climate

• hot, dry summer

• high PE & low AE in summer

• seasonal deficit

• primary limiting factor: dry summer

• alfisols

• vegetation

• drought resistant trees and shrubs

• small, thick waxy leaves

• adapted to fire

Image credit: US Department of the Interior, Burea of Land Management, Medford District, Oregon. Chaparral. http://www.blm.gov/or/resources/recreation/tablerock/table-rock-plants-chaparral.php

Midlatitude Dedicuous & Mixed Forest

• Cfa (humid subtropical), Cfb (marine west coast), Dfa & Dfb (humid continental) climates

• moderate to moderately high AE & PE

• seasonal surplus; little deficit

• moderate to moderately high NPP

• primary limiting factor: cold winter

• ultisols & alfisols

• vegetation

• deciduous broadleaf trees dominate

• oak, maple, beech, hickory, elm

• also evergreen needleleaf trees

• understory generally well-developed

• moderate species diversity

Northern Coniferous (Boreal) Forest (Taiga)

• Dfc & Dfd (humid continental with cool to cold summers)

• moderately low precipitation; primarily in summer

• moderately low AE and PE

• seasonal surplus; no deficit

• moderately low NPP

• primary limiting factor: cold temperatures

• spodosols; thick litter layer

• vegetation: coniferous forests

• needleleaf evergreen trees (spruce, pine, fir, larch)

• broadleaf deciduous trees in early successional sites

• sparse understory

• fire

Image credit: K.A. Lemke
Image credit: Tom Detwyler, World Biomes CD-ROM, Environmental Views series. Used with permission from Optilearn Inc. Stevens Point, WI.

Image credit: U.S. Fish & Wildlife Service, Digital Library System http://images.fws.gov/

C. SAVANNA BIOME

• Aw (tropical wet and dry or savanna) and drier margins of Af (tropical rainforest)

• high PE

• seasonally high AE

• seasonal drought

• moderate NPP

• primary limiting factor: dry winter

• alfisols, some ultisols

• vegetation

• continuous grass cover

• scattered drought resistant trees

• trees have deciduous habit or deep tap roots

• moderately high diversity

First image credit: B. Wolff, United Nations. World Biomes CD-ROM, Environmental Views series. Used with permission from Optilearn Inc. Stevens Point, WI.
Second image credit: M. Boulton, F.A.O. World Biomes CD-ROM, Environmental Views series. Used with permission from Optilearn Inc. Stevens Point, WI.

Tanzania

Zambia

D. GRASSLAND BIOME

• BSh & BS (subtropical and midlatitude steppe) and drier margins of Cf and Df (humid subtropical and humid continental)

• variable PE

• moderate to moderately low AE

• seasonal drought

• moderate NPP

• primary limiting factor: lack of moisture

• primarily mollisols; some aridisols

• vegetation

• prairie grassland (tallgrasses; up to 6 ft)

• steppe grassland (shortgrasses)

• extensive root systems

• fire tolerant

• animal adaptation strategies: herding; burrowing

Image credit: Bureau of Land Management (BLM), Wyoming http://www.wy.blm.gov/botany/habitats.htm

Image credit: Lynn Betts, , USDA Natural Resources Conservation Service http://photogallery.nrcs.usda.gov/Detail.asp

E. DESERT BIOME

• BWh (tropical desert) & BWk (midlatitude desert)

• high PE in tropical deserts; seasonally high PE in midlatitude deserts

• low AE

• chronic drought

• low NPP

• primary limiting factor: lack of moisture

• aridisols, entisols

• vegetation

• drought resistant shrubs, succulents, annuals

• water storage

• reduced leaf area

• tap roots

• raingreen habit

• animal adaptation strategies: burrowing, nocturnal

Australia

Image credit: K.A. Lemke
Arizona

Image credit: K.A. Lemke

F. TUNDRA BIOME

• ET (tundra), Dw & Dfd (subarctic) climates

• low PE and low AE

• low precipitation

• low NPP

• primary limiting factor: cold temperatures year-round

• slow photosynthesis, frozen water

• gelisols

• vegetation

• shrubs, mosses, lichens; no trees

• low lying vegetation gains protection from cold winter temperatures by snow cover

• low species diversity

• animal adaptation strateties: hibernation, fat protection, migration

First image credit: U.S. Fish & Wildlife Service, Digital Library System http://images.fws.gov/
Second image credit: U.S. Fish & Wildlife Service, Digital Library System http://images.fws.gov/

Alpine tundra

Image credit: K.A. Lemke