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Ecology Week 1. Chapter 50: Introduction to Ecology and the Biosphere Chapter 54: Ecosystems J Liu September ___, 2008. Big to Small. Water Biomes. Lakes—oligotrophic, eutrophic; littoral/ limnetic zones Wetlands Streams and Rivers Estuaries Intertidal Zones Oceanic Pelagic Biome
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Ecology Week 1 Chapter 50: Introduction to Ecology and the Biosphere Chapter 54: Ecosystems J Liu September ___, 2008
Water Biomes • Lakes—oligotrophic, eutrophic; littoral/ limnetic zones • Wetlands • Streams and Rivers • Estuaries • Intertidal Zones • Oceanic Pelagic Biome • Coral Reefs • Marine Benthic Zone
Land Biomes • Tropical Forest • Desert • Savanna • Chaparral • Temperate Grassland • Coniferous Forest • Temperate Broadleaf Forest • Tundra—permafrost
Seasonal Turnover • Spring and fall • Switch oxygen rich and nutrient rich water • Thermocline
Ecosystems! Some Basics. • Are made up of all the biotic (alive things) and abiotic (immortal, not alive things) in a community • Nutrients are cycled; energy isn’t Abiotic Biotic
“Trophic Relationships” (a.k.a. Food Chains) • Autotrophs (primary producers) • Heterotrophs (primary, secondary, and tertiary consumers) • Detritivores (decomposers) • Yum! :D
Limiting Primary Productivity • Primary production—amount of light energy converted to chemical energy per time • Little energy from the sun is made use of • NPP = GPP – R • In water: photic zone, upwelling, and eutrophication • On land: actual evapotranspiration • In general: limiting nutrients, especially nitrogen and phosphorus
Production (In)efficiency • Secondary production—how much chemical energy becomes new biomass • Production efficiency = NSP / APP • Trophic efficiency—how much energy is transferred to the next trophic level • Pyramids (production, biomass, numbers)
The Green World Hypothesis • Herbivores don’t eat all the plants because other things kill them first • Plant defenses, limited nutrients, abiotic factors, competition (inter-/intra- specific)
Biogeochemical Cycles • So called because they involve biotic and abiotic components • Global versus local UnAvailable Available Organic Organisms Coal, oil, peat InOrganic ROCKS. Water, soil, etc.
The Water Cycle Wind Precipitation Evaporation Runoff
The Carbon Cycle Carbon dioxide Burning Fossil Fuels Photosynthesis Respiration Decomposition
The Nitrogen Cycle (It’s too hard to draw)
The Phosphorus Cycle AHHHH this one’s hard to draw too T.T Plant uptake Plant Eaten Weathering/ Runoff Geologic Uplift Leaching Decompose Sedimentation
Human Influences • Moving nutrients from one part of the biosphere to another • Critical load—the amount of a nutrient that can be absorbed by plants without damaging the ecosystem • Cultural eutrophication
Acid Rain • pH less than 5.6 • Lowers pH of water, changes soil composition
Toxins • Biological magnification—toxins become more concentrated in higher trophic levels • Stay in the environment for a long time
Carbon Dioxide in the Atmosphere • C4 plants replaced by C3 plants • Greenhouse effect—reflection of infrared back to Earth by carbon dioxide and dihydrogen monoxide ( ^^ )
The Ozone Layer • Protects the surface from UV • Depleted by CFCs • Chlorine is a catalyst • Skin cancer and cataracts