Temperate Grasslands: Ecology, Adaptations, and Floristics, Summaries of Climatology

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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

§ 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

§ 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

§ American prairie gradients: west to east Shortgrass prairie, Nebraska Konza Prairie - mixed grass, Kansas Curtis Prairie

• tall grass, Wisconsin

§ soils are rich 'chernozens' or 'udolls’ § thick organic layer of very dark humus; active earthworm and soil fauna activity making this soil one of the most productive of terrestrial systems § light rainfall and high evaporation makes mild leaching; therefore soil is neutral or only slightly acidic A horizon

§ Changes : fire supression - once frequent and kept out woody species § fire for agriculture still prevalent in South African veldt and South American pampas

§ 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) 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 )

§ Floristics of American prairies: § Prairie peninsula of tall grasses may have extended to East Coast - floristic (and faunistic) linkages

§ 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) Amorpha canadense Leadplant (Fabaceae)