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31 Cards in this Set
- Front
- Back
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Ecosystems |
Interacting system made up of all living and nonliving objects in a specified volume of space |
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Wetlands as Kidneys of Landscape |
Filter out sediment, nutrients, and pollutants |
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Distinguishing features of wetlands |
1) water at the surface or root zone 2) hydric soils 3)hydrophytes or lack of flood intolerant biota |
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Ecotone |
region of transition between terrestial and deep water ecosystems that have edge effect with increased biodiversity |
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hydrogeomorpholgy |
determined by climate and geomorphology |
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Biotic Control of wetlands |
1) microbes catalyze chemical changes in soils and control nutrient availibility 2) vegetation interupts water flows, trap sediments, build peat, and affect water levels 3) sediments and organic matter interrupt water flows and peat affects duration and frequency of flooding |
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Slight changes in hydrologic conditions |
can result in large changes in species composition and richness and ecosystem productivity |
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hydroperiod |
seasonal pattern of water level in seasonal or intermittently, permanently or temporarily flooded, or riparian or tidal wetlands: measured
flood duration and frequency |
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water budget |
change in water volume storage over time in terms of depth and volume. 3 factors: 1) inflows and outflows 2)surface contours of landscape 3) soil, geology, groundwater |
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surface water |
overland flow; land use and soil type are more important than slope or vegetation
channelized streamflow |
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hydrograph of storm flow |
rising limb, peak flow that lags behind precipitation, and receding limb |
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groundwater |
depends on position in hydrologic flow path- base of slope, floodplain, depression, perched, or tidal |
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Bogs |
Groundwater discharge areas, water is acidic, low in nutrients and have accumulated peat |
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Fens |
recharge areas, neutral to alkaline, dissolved minerals and nutrients |
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net percipitation |
precipitation - interception |
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Hydrology affects wetland functions |
1) vegetation composition 2)primary production 3) accumulation of organic material 4) nutrient cycling and availability |
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pulsing hydroperiods |
increase primary production |
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Element cycling |
transport and transformation of chemicals within and among ecosystems |
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Nitrogen cycling |
1) most limiting nutrient in flooded soils 2) microbial denitrification to N2 from N makes N less available 3) anthropogenic N deposited atmospherically can be a significant source 4)N is important for oxidation/decomp of organic matter |
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Carbon cycle |
1) reduction of CO2 by light or chemical energy is the source of most organic matter 2) C is involved in nearly all energy creating or consuming process in biology 3) inorganic C > organic 4) pathways consist of photosynthesis, respiration, fermentation, methanogenesis, and methane oxidation - linked reactions to sulfate and nitrate reduction |
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Evidence of anthropogenic activites |
1) Keeling curve; Mona Loa: 30% increase since 1958 2) Ice Cores show steep increase starting in industrial age 3) global increase of mass balance of CO2 4) isotopes indicate new C in atmosphere has fossil fuel origins |
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Phosphorous cycle |
1) limiting nutrient in bogs, marshes, and swamps 2)clay bound, inorganic P into riparian wetlands supports vegetation 3) organic P stored in peat or exported |
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sulfur cycle |
1) rarely limiting 2) transforming by microbial mediated pathways when sulfate is electron acceptor |
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Mercury cycle |
1) combustion introduced Hg to air, wet and dry deposition, microbial transformation to MeHg, bioaccumulates and biomagnifies in food chains; toxic especially at top of food chains |
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Storage of elements |
Leaves, stems, roots, water, litter, detritus, sediment |
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flows of elements |
surface water, n fixation, denitrification, groundwater, atmospheric, throughfall, litterfall, decomp, volatilization |
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morphological adaptations |
1) arenchyma (honeycomb structure; diffused oxygen) 2) adventitious root development above soil in anaerobic times 3) pneumataphores 4) prop roots |
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physiological adaptations |
pressurized gas flow and rhizosphere oxygenation |
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whole plant strategies |
timing of seed production: bouyant seeds: vivipary; germination while still attached, seed bank: tubers, roots, and seeds that survive long submergence |
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autogenic succession |
vegetation occurs in a recognizable sequence, change brought about by biota, change is linear towards climax ecosystem |
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allogenic succesion |
distribution of species is governed by response to environment, species overlap, no two species share same zone, no communities, no climax |
