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Primary, heavily disturbed. Secondary, tree stabilized dunes. Wetland/Freshwater. Forest, Canopy/Understory. Naturalizing the Built Environment Justin Borevitz Ecology & Evolution University of Chicago http://naturalvariation.org/.
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Primary, heavily disturbed Secondary, tree stabilized dunes Wetland/Freshwater Forest, Canopy/Understory Naturalizing the Built EnvironmentJustin BorevitzEcology & EvolutionUniversity of Chicagohttp://naturalvariation.org/ Naturalizing the Built EnvironmentJustin BorevitzEcology & EvolutionUniversity of Chicagohttp://naturalvariation.org/ Indiana Dunes National Lakeshore
Talk Outline Talk Outline • Prairie Ecosystems • Succession (Ecosystem Evolution/Maturation) • Henry Chandler Cowels • EcoFootprint • Working with the Nature • Ecological Design • Seasonal Variation • Passive Solar • Optimizing Systems • Food, water, energy • Center for Ecological Conservation Genomics
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 Greektonos or tension – in other words, • a place where ecologies are in tension Chicago Architecture Foundation
EcoZones/ Biomes/ Realms • Australasia | Antarctic | Afrotropic | Indo-MalayanNearctic | Neotropic | Oceania | Palearctic
Short, mixed, and Tall grass prairie http://climate.konza.ksu.edu/
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. • 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
Protecting Meristems • Plants need active shoot apices and other meristems to provide new growth or re-growth after harvest. • Critical management period for grasses occurs during reproductive growth (after transition) when internode elongation elevates the shoot apex to a vulnerable height. • Timothy, smooth bromegrass, and prairie grass are examples of grasses susceptible to mismanagement (untimely defoliation). • Defer grazing or clipping until crown buds are ready for growth (boot stage or later).
Sodhouses To overcome the lack of timber to build their houses the Homesteaders used sods of earth cut from the Plains as bricks. They built their houses out of this earth and called them sod houses. Many sod houses were huge affairs, with many rooms, but they all suffered from the same problems. They were dirty, drafty and leaked whenever it rained. The walls and floor were infested with lice, which crawled over the Homesteaders as they slept. Mud fell off the ceiling into the Homesteaders’ cooking pots, and germs were rife. Despite this, many Homesteaders were proud of their first ‘soddy’ and often lived in them for decades.
Soil is more than dirt • We covered the biotic part • food web of a healthy soil • But what about the abiotic part? • Mineral, rock, clay, sand, loam, loess, humus “mollisols” prairie soil • C deep grass roots • Black and rich • in warm moist • tall grass prairies
Benefits of prairie grazing • Promotes species diversity • Increases light availability to plants, promoting photosynthesis and growth • Can change species composition • Decreases woody plant growth while promoting grazing-tolerant plants.
American bison European bison http://www.ultimateungulate.com/Cetartiodactyla/Bovinae.html
Fires The dry Plains were provided the perfect conditions for fires to start. The long hot summers left the Prairie Grass and the homesteaders’ crops bone dry. Accidental fires started by a spark or a bit of broken glass lying on the ground and reflecting the sun were a disaster for the homesteaders. Unless the fire could be stopped quickly by beating, it soon spread. Without any water to put out the fire, the homesteaders were forced to hide in their sod houses until their crops were destroyed and the fire died.
Healthy burns in the arboretum • Burns over large areas • Rotation of a 4-year burn schedule • Adjacent to areas not burned in the last 2 years • Seasonal rotation of burns
Ecological Relations of the vegetation on the sand dunes of Lake Michigan (1899) • Plant Formations should be found that are rapidly changing to another type by means of changing environment. • Can be seen in no better place than Sand Dunes due to instability.. • Plant Society – product of past and present environmental conditions • Plant Formations are investigated • species composition • The progressive changes that take place and the factors in the environment which caused these changes.
Ecological Factors • Light and Heat • Open exposed to extremes • Wind • From the North west, Michigan City dunes most affected • Soil • Quartz sand, deplete of organic material • Water • Holding capacity of sand • Other factors • Fire, topography, other animals and plants
Plant Societies • Beach • Lower, middle, upper • Embroyonic or Stationary Beach Dunes • Rapid growth, slow growth • Active or Wandering Dune Complex • Transformation • Physical and Biological features • Encroachment • Capture (by vegetation)
Plant Succession: An analysis of the development of Vegetation (1916) • “Treats the formation as an organism with structures and functions like an individual plant…. The formation is defined as the climax community of a natural area where the essential climatic [habitat] relations are similar or identical” • “sere” - term used to describe the entire successional series, eg developmental process • [Thus succession is development of a formation with infant, child, juvenile, and adult phases. But that can revert to earlier phases and start again.] • Clements 1919 comprehensive review
Footprint Reducing Risks by Setting Measurable Targets Dr. Mathis Wackernagel www.FootprintNetwork.org
House Are we getting to big for our house?
Global equity Who is getting what?
People vs. nature What about land for other species? ?
67% Low-Productivity Ocean Bioproductive Segments Bioproductive segments 22% 4% Biologically Productive Ocean 11% Deserts, Ice Caps and Barren Land 18% Biologically Productive Land
Footprint components Fossil Fuel Built-up Waste Food Fibres absorption
Global Footprint Global Footprint Accounts (in global hectares/person, 1999 data) Ecological Demand (Ecological Footprint) Ecological Supply (Biocapacity) Footprint Areas for: Biocapacity Areas: Growing Crops 0.53 Crop land 0.53 Grazing Animals 0.12 Grazing land 0.27 Settlements & infrastructure 0.10 Built-up area 0.10 Producing timber & fuelwood 0.33 Forest 0.86 Absorbing excess CO2 1.07 Harvesting Fish 0.14 Fishing Grounds 0.14 Total Global Demand 2.29 Total Global Supply 1.90 Demand Exceeds Supply By 20% >
Footprint data for 8 countries Footprint data for 8 countries
The Energy Problem • How will society meet growing energy demands in a sustainable manner? • Fossil-fuels currently supply ~80% of world energy demand.
Biofuels as an Alternative • Biofuels are not THE answer to sustainable energy, but biofuels may be part of the answer • Biofuels may offer advantages over fossil fuels, but the magnitude of these advantages depends on how a biofuel crop is grown and converted into a usable fuel
Analysis of Alternative Biofuels • “First generation” biofuels: food-based biofuels that are currently commercially available: • Corn-grain ethanol • Soy Biodiesel • “Second generation” biofuels: cellulosic biofuels of the future • Diverse prairie biomass
Biofuels.. Renewable/sustainable? • Fossil fuel subsidy? • Soil fertility subsidy? • Water subsidy? • Land use subsidy? • Biodiversity/ecological subsidy? • Farmer subsidy? • Civil/ social subsidy?
How Much Do They Supply? • Corn grain ethanol (2005): • 14.3% of the US corn harvest was used to produce 1.48x1010 L of ethanol annually • Energetically equivalent to 1.72% of US gasoline use • Soy biodiesel (2005) • 1.5% of the US soybean harvest produced 2.56x108 L of biodiesel annually • 0.09% of US diesel use
But How Much Could They Supply? • Devoting all US corn and soybean production to biodiesel and ethanol would generate: • 12% of US gasoline consumption • 6% of US diesel consumption • In terms of net energy gain: • 2.4% of US gasoline consumption • 2.9% of US diesel consumption
Second Generation Biofuels: Cellulosic Feedstock… Switchgrass Wheat Straw Hybrid Poplar Corn Stalks