Where is Here Lecture 2
The Urban Savannah Frontiers of the Prairie - Frank Lloyd Wright’s
- Prairie Skyscraper, Price Tower Arts center
Chicago is as it was on the Ecotone - coined from a combination of eco(logy) plus –tone
- from the Greek tonos or tension – in other words,
- a place where ecologies are in tension
oikos-olgie, Ecology Study of the household, Total relationship .. of organic and inorganic environment Ecology is the scientific study of the distribution and abundance of living organisms and how the distribution and abundance are affected by interactions between the organisms and their environment 1866 Ernst Haeckel “ontogeny recapitulates phylogeny” Father of Evo-Devo, but also faked some data, like Mendel and Darwin?
Ecosystem 1935, Tansley studying math and systems theory, quantifying relationships and community at various interlocking scales A biome is a homogeneous ecological formation that exists over a large region as tundra or steppes. The biosphere comprises all of the Earth's biomes -- the entirety of places where life is possible -- from the highest mountains to the depths of the oceans.
EcoZones/ Biomes/ Realms Australasia | Antarctic | Afrotropic | Indo-Malayan Nearctic | Neotropic | Oceania | Palearctic
EcoRegions An ecoregion (ecological region), sometimes called a bioregion, is the next smallest ecologically and geographically defined area beneath "realm" or "ecozone". The WWF has identified 825 terrestrial ecoregions, and approximately 450 freshwater ecoregions across the Earth. "recurring pattern of ecosystems associated with characteristic combinations of soil and landform that characterise that region" (Brunckhorst, 2000). Others have defined ecoregions as areas of ecological potential based on combinations of biophysical parameters such as climate and topography. Biodiversity is also an important aspect of the study of ecoregions. The biodiversity of flora, fauna and ecosystems that characterise an ecoregion tend to be distinct from that of other ecoregions Great Plains has 15 EcoRegions, Chicago, “Central Tall Grasslands -> Prairie Oak Transition”
Upper Midwest forest-savanna transition (NA0415) One of the three ecotonal units separating the vast Great Plains grasslands from the forests of the eastern U.S. is the Upper Midwest Forest/Savanna Transition Zone The predominance of trees in a mosaic of forests, savannas, and woodlands, and by differences in dominance of major tree species. oak, maple, basswood woodland, forest, and savanna ecosystem (Küchler 1985). The boundaries of this ecoregion were heavily influenced by fire and drought
Central forest-grasslands transition extends from northern Illinois, across much of Missouri, and into eastern Kansas, Oklahoma, and Texas. Is one of the larger savanna-type ecoregions, covering more than 380,000 km2 separates the Eastern Deciduous Forests from the tallgrass and mixed grass prairies. higher tree and shrub densities. Annual precipitation ranges from 600-1040 mm, with wetter areas supporting a more closed tree canopy. The uniform soil type (mollisols) unites this wide-ranging ecoregion. Unfortunately, virtually no intact habitat remains because this ecoregion is one of the most converted of U.S. ecoregions. Almost all of this unit is intensively farmed for corn and soybeans.
Danger Danger Tall Grass Prairies. 99.9% plowed under 464 species declined “long term survival is in danger 328 (71%) are endemic 13 amphibians, 18 reptiles, 72 mammals, 160 butterflies, 222 birds, 1595 species of grasses, sedges and wildflowers Species Richness index 2095, - vs California Redwood forest 1710, Everglades 1855
Prairie global distribution 1/3 or earths land surface Other world prairie ecosystems? - Could we survive today without prairie grasslands? What are our major food stuffs?
For example, a Temperate grassland or shrubland biome is known commonly as steppe in central Asia, savanna or veld in southern Africa, prairie in North America, pampa in South America and outback or scrub in Australia. Sometimes an entire biome may be targeted for protection, especially under an individual nation's Biodiversity Action Plan. Independent evolutionary origins, similarities on species compositions, species dependencies? Original site of Crop domestication Could we survive today without prairie grasslands? What are our major food stuffs?
Glaciers give way Chicago Encyclopedia - 11,000 years ago
- Mastodons and woolly mammoths
- Evergreen Forest (still remnant evergreens)
- Before settlement map (browse)
- Humans? Large animals? giant beaver (Castoroides ohioensis), Harlan's musk ox (Bootherium bombifrons), and stag-moose (Cervalces scotti ) all occurred in the Chicago region
World Grasslands
Bison First Europeans observation Coronado in 1540 “hunters following endless herds.. Impossible to number.” precontact population estimated 25-125Million
Badlands Badlands are a type of arid terrain with clay-rich soil that has been extensively eroded by wind and water. Canyons, ravines, gullies, hoodoos and other such geological forms are common in badlands. They are often difficult to walk upon. Badlands usually have a spectacular color display that alternates from dark black/blue coal stria to bright clays to red scoria. The term "badlands" has dual origins: the Lakota called the topography "mako sica", literally "bad lands",
Loess Hills The Loess Hills are generally located between 1 and 15 miles east of the Missouri River channel. These hills are the first rise in land beyond the flood plain, forming something of a "front range" for Iowa, and parts of Missouri and Nebraska adjacent to the Missouri River. During the Ice Age, glaciers advanced into the middle of North America, grinding underlying rock into dust-like "glacial flour".
Making of Lake Michigan Whenever a glacier stabilizes for a time at the same position, the transported material accumulates into hilly moraines, several of which occur in the Chicago region
Sandy springboard Lake floor depressed because the heavy weight of the ice above the land surface The land depressed by the glacial ice gradually uplifted, a process called isostatic rebound . Good for skyscrapers!? 150’ topsoil
Terra forming -17,000 -- -11,000.. Evergreen Spruces (white and black) and Deciduous Popular, Ash, Ironwook. - Unique on the globe, warm winters cool summers
-11,000 end of Pleistocene, beginning of Holocene warming to deciduous forest dominated by black ash, elm (Ulmus), and oak prevailed , better than today (few evergreens left) About 6,000 years ago, the climate again became drier, and the modern mosaic of prairie and woodland began to develop. Elm and other fire-sensitive trees decreased in abundance, and oak became the predominate tree on the landscape.
Open Savannah Oak architecture Open Savannah Oak architecture Lots of light near a grassland Native Americans provided a constant source of ignition
Thicker forests were less subject to fire, and generally were on the protected east sides of the rivers. Eg Aurora Why do grasses withstand fire and trees/shrubs don’t?
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