Ecosystem Ecology

• Three types of ecosystems: ocean, freshwater, and terrestrial
• Ocean is most common ecosystem, 70% of Earth's surface, phytoplankton( 40% of all photosynthesis)
• Freshwater is the rarest ecosystem (2%) and are lakes, rivers, streams and spring
• Terrestrial are grouped into biomes like deserts, tundras and rainforests
• Energy flow is linear
• Matter is recycled
• 1st law of thermo dynamics: energy cannot be created or destroyed, only transferred
• energy must cycle to be available for other organisms
• Biogeochemical cycle: processes by which matter cycles between living and non-living
• Ecosystems must have producers and decomposers
• Primary produces > primary consumers > secondary consumers > tertiary consumers > decomposers
• primary producers ultimately supports all others
• Decompsers recycle organic matter from remains of all members of the food chain. Producers can use inorganic molecules produced.
• sunlight is the main energy source for majority of ecosystems
• Gross primary production( GPP): the amount of energy taken from the sun and turned into matter
• Net Primary Production (NPP): amount of energy left after cell respiration
• Secondary production : amount of chemical energy in food that is converted into consumer biomass
• Assimilation: organism uses and incorporated energy taken for growth and reproduction
• usually only 10% of productivity transfer from tropic levels
• Only 1% of solar radiation striking plants is converted into chemical E
• Four factors of Biogeochemical cycles: biological importance, form available to organisms, major reservoirs, and key processes
• Water Cycle: essential to all organisms, most found in liquid form, ocean: 97%
• Carbon Cycle: Carbon based molecules essential to all organisms, most found in the atmosphere, fossil fuels, soils, biomass, and rocks.
• Phosphorus cycle: Phosphorus is a nutrient that is essential for plant growth and is found in the soil. Weathering of rocks and minerals, returned by decomposers
• Nitrogen cycle: The process by which nitrogen is recycled through the atmosphere, soil, and living organisms. The main resivor of nitrogen is the atmosphere.