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Temperate Grasslands
Temperate Grasslands
Temperate Grasslands
§ One of the most extensive of the biomes § North America: prairies 350 million ha running from eastern deciduous forest border to western cordilleras Konza Prairie, Kansas
Temperate Grasslands
§ One of the most extensive of the biomes § Eurasia: steppes 250 million ha running from Hungary to Manchuria Mongolian steppe Russian Steppe
Temperate Grasslands
§ One of the most extensive of the biomes § Argentina, Uruguay: pampas
§ One of the most extensive of the biomes § Argentina, Uruguay: pampas Cortaderia - pampas grass § One of the most extensive of the biomes § South Africa: grassveldt
Temperate Grasslands
§ Temperate grasslands are adapted to recurring drought (50 - 120 cm rain) § Temperate grasslands appear homogenous but important structural and floristic differences have developed in response to regional and local conditions (e.g. in prairie province) § increasing latitude & east to west: warm to cold and moist to dry
Temperate Grasslands
§ American prairie gradients: west to east Shortgrass prairie, Nebraska Konza Prairie - mixed grass, Kansas Curtis Prairie
§ Changes : large areas converted to agriculture (wheat, maize, legumes) loss of Canadian grasslands by 1990 § Changes : large areas converted to agriculture (wheat, maize, legumes) % grasslands & wetlands converted from 2008- § Changes : loss of characteristic cursorial fauna of ungulates (bison, antelope, gazelle, wild horse) or equivalent flightless birds in South America (rhea)
Temperate Grasslands
Pronghorns on short grass prairie, Nebraska Buffalo, South Dakota § Changes : loss of characteristic cursorial fauna of ungulates (bison, antelope, gazelle, wild horse) or equivalent flightless birds in South America (rhea)
Temperate Grasslands
Antelope, Asian steppes Rhea, Argentinan pampas
§ grasses and sedges have high silica content in leaves § ungulates acquired early on high-crowned teeth in which growth continually replaces the worn surfaces as adaptation § grasses and sedges have ability to resprout after grazing (good example is the prairie ungulate replacer: the lawn mower ) § Changes : major extinction of megafauna in North America from the Pleistocene - Holocene Missouri in Pliocene 5-6mya “Overkill” hypothesis? § Floristics of American prairies: § Prairie peninsula of tall grasses may have extended to East Coast - floristic (and faunistic) linkages
Temperate Grasslands
§ Floristics of American prairies: § few endemic species suggesting that prairies developed comparatively recently and attained present distribution only in post- glaciation or Holocene (Axelrod, 1985)
Temperate Grasslands
Amorpha canadense Leadplant (Fabaceae)
§ Floristics of American prairies: 3 major families § Asteraceae - composites Silphium terebinthinaceum / laciniatum - prairie dock, compass plant Echinacea - purple coneflower § Floristics of American prairies: 3 major families § Asteraceae - composites Liatris aspera - blazing star Solidago rigida - stiff goldenrod § Floristics of American prairies:
Temperate Grasslands
Anemone patens - pasque flower (Ranunculaceae) Extra Credit! Take digital image of this “harbinger of spring” for prairies we will revisit some of these biomes after first examining the twin issues of evolution of earth and life Close the book on biomes for now
