Producers Make their own food Photosynthesis Examples? Lii L gh gh tt e enne errg gyy 6CO2 + 6H2O + ------> C6H12O6 + 6O2
Consumers Feed on other things Herbivores Carnivores Omnivores Detrivores
Decomposers Break down dead organisms and waste products Examples?
Energy Flow Energy passes from one organism to the next Trophic level: each step in this flow of energy Food chain: straight path Food web Interconnected food chains More realistic than food chain; why?
Biogeochemical Cycles Matter cycles through ecosystems Five cycles Carbon Hydrologic (water) Nitrogen Sulfur Phosphorus
Carbon Cycle Essential component for life Gas (CO2) in atmosphere Several forms in ocean Can take a long time—think fossil fuels Photosynthesis Cellular respirationCO2 Sugar CO2
Nitrogen Fixation Specialized bacteria Split atmospheric nitrogen and combine it with hydrogen
Sulfur Cycle Underground sedimentary rocks and minerals Erosion releases compounds to ocean Volcanoes Essential component of proteins
Phosphorus Cycle No atmospheric component Phosphates used in DNA and ATP (chemical energy) Phosphates move through the food chainLand Organism Organism Land
Ecological Niche Everything about an organism Adaptations Use of resources Lifestyle Habitat
Ecological Niche Two species cannot occupy the same niche: why? Resource partitioning Reduces niche overlap Reduces competition
Resource Partitioning At Work!
Species Interactions No species lives in complete isolation Symbiosis Intimate relationship between members of at least 2 species Mutualism, commensalism, parasitism Result of coevolution Other interactions Predation, competition
Mutualism Both species benefit
Commensalism One species benefits, other not affected
Parasitism Parasite benefits, host is “harmed” Ectoparasites & endoparasites
Species Interactions Predation: consumption of one species by another Coevolution: “arms race”
Avoiding Predators Mechanical defenses Social groups Camouflage Protective chemicals
Species Interactions Competition: two or more organisms attempting to use the same resource Intraspecific vs. interspecific
Keystone Species Crucial to maintenance of an ecosystem Loss affects many other species Examples? This idea is being challenged; why?
Case Study: Global Climate Change Atmospheric CO2 increased dramatically. Why? 10 warmest years have occurred since 1990 2005 warmest 1998 second warmest 2002 third warmest Earth’s temperatures may rise 1.8o – 4.0o C (3.2o – 7.2o F) by end of 21st century What could occur?
Case Study: Global Climate Change Kyoto Protocol – International climate change conference – Kyoto, Japan 1997 Highly developed countries to cut CO2 emissions ~ 5.2% by 2012 US Department of Energy Automotive vehicles designed for better gas mileage High efficiency wind turbines