270 likes | 407 Views
Chapter 3 The Biosphere. 3.1 What is ecology? . Ecology : scientific study of interactions among & betwn org & env’t Ernst Haeckel (1866)-oikos: “house” Largest “house”: Biosphere: Life Layer: land, water, & atmo, supports life 8 Km atm to 11Km below ocean. Levels of Organization.
E N D
3.1 What is ecology? • Ecology: scientific study of interactions among & betwn org & env’t • Ernst Haeckel (1866)-oikos: “house” • Largest “house”: Biosphere: • Life Layer: land, water, & atmo, supports life • 8 Km atm to 11Km below ocean
Levels of Organization Biome: eco w/ same climate & dominate community All org in area w/ env’t Diff pop in same area Grp of same organism (species) in 1 area 1 organism
Ecological Research • Observation: 1st step in designing experiment/model • Experimentation: test hypo • artificial env’t in lab or natural env’t • Model: use computer/formula to study • for studies over time or large spacial scale • global warming • for ethical reasons Ex: use of mice
3.2 Energy Flow • Sunlight: main NRG source for life • Autotrophs: (producers) produce food using E from env’t • Photosynthesis: plants/algae convert sunlight E into food NRG (Carbs) • 6CO2 + 6H2OC6H12O6 + 6O2
Autotroph (cont) • Chemosynthesis: bacteria convert chemical NRG into carb NRG
Heterotroph-Consumer: eat food for NRG Herbivore: plant eaters Carnivore: animal eaters Omnivore: eat plants & animals
Heterotrophs (cont) Detrivore: feed on remains/dead matter Decomposer: breakdown organic matter
Food Chain • One-way stepwise flow of NRG
Food Web • More complex feeding relationships (many food chains)
Trophic Levels • NRG steps from sun, producers = 1st level l
Energy Pyramid • Rule of 10%-decrease amt of NRG at each trophic level
Biomass Pyramid • Amount of living organic tissue/level
Pyramid of Numbers • # of indiv org at each level
3.3 Cycles of Matter (within/betwn ecosystems) • Biogeochemical cycles: forms of matter • connects biology, geological and chemical aspects of the biosphere • Continuous Cycle Never stops
Water Cycle • Precipitation/condensation (dew) • Evaportation/transpiration (plant evap) Condensation Precip- rain Transpiration (evap from plants)
Carbon Cycle • CO2 to producer w/photosyn (sugar) • Consumer eats prod w/C (carbs) • Cellular respir breaks down food • C released back into eco as CO2
Nitrogen Cycle • Org require N for Amino Acid for proteins • N2 (gas) abundant in atmo • N-fixing-bacteria (on legume root) turn N2 into ammonia (useable by plants) • Decomposers return N2 to atmo
Limiting Nutrient • Scarce nutrient, cycles slowly thru sys • Ex: Algae Bloom: growth removes O2 causing other org to die
4.2 What shapes an Ecosystem? • Biotic Factors: living (plants/anmls) • Abiotic Factors: physical (temp, precip) • Both influence survival, growth, & productivity in habitat (area where org lives)
Niche • Role in community, “occupation” • Depends on abiotic & biotic factors • One species/niche (competitive exclusion principle) • Includes: food it eats, how it eats, when & how it reproduces
Community Interactions 1. Competition: Struggle btw org for limited resources (food, water)
Community Interaction 2. Predation: 1 org hunts/kills for food • Predator/Prey
Community Interaction 3. Symbiosis: 2 species close together • Mutualism: Both benefit (win-win) • Commensalism: 1 benefits/ other not helped/harmed
Parasitism: 1 (helped) lives in/on another (harmed) • Ex: Aphids & tapeworm
Ecological Succession • Predicatable changes in ecosystem • Primary Succession: w/no soil • Pioneer species (1st species): Lichens & mosses break rock to soil
Secondary Succession: disturbance w/o removing soil • Ex: Fire, tornado, hurricanes