This chapter explain how the first and second laws of thermodynamics apply to ecosystems; define and compare gross primary production, net primary production, and standing crop; explain why energy flows but nutrients cycle within an ecosystem; explain what factors may limit primary production in aquatic ecosystems. | Ch. 55 Warm-Up Draw an energy pyramid and label the following trophic levels: Primary producer Primary consumer Secondary consumer Tertiary consumer What is an example of an organism at each level of the pyramid in #1? If 5000 J of energy is available in producers, how much of that energy would be available to tertiary consumers? Define Ch. 55 Terms: Autotroph Heterotroph Detritivore Gross primary production (GPP) Net primary production (NPP) Biogeochemical cycle Nitrogen fixation Chapter 55: Ecosystems You Must Know: How energy flows through the ecosystem (food chains and food webs) The difference between gross primary productivity and net primary productivity. The carbon and nitrogen biogeochemical cycles. Ecosystems Ecosystem = sum of all the organisms living within its boundaries (biotic community) + abiotic factors with which they interact Involves two unique processes: Energy flow Chemical cycling Overview of energy & nutrient dynamics Energy Flow in an Ecosystem Energy cannot be recycled must be constantly supplied to an ecosystem (mostly by SUN) The autotrophs (“self feeders”) are the primary producers, and are usually photosynthetic (plants or algae). They use light energy to synthesize sugars and other organic compounds. Heterotrophs (“other feeders”) – can’t make own food Heterotrophs are at trophic levels above the primary producers and depend on their photosynthetic output. Herbivores that eat primary producers are called primary consumers. Carnivores that eat herbivores are called secondary consumers. Carnivores that eat secondary consumers are called tertiary consumers. Another important group of heterotrophs is the detritivores, or decomposers. They get energy from detritus, nonliving organic material, and play an important role in material cycling. Main decomposers: fungi & prokaryotes Primary Production Primary production = amt. of light energy that is converted to chemical energy Gross primary production (GPP): total primary production in an . | Ch. 55 Warm-Up Draw an energy pyramid and label the following trophic levels: Primary producer Primary consumer Secondary consumer Tertiary consumer What is an example of an organism at each level of the pyramid in #1? If 5000 J of energy is available in producers, how much of that energy would be available to tertiary consumers? Define Ch. 55 Terms: Autotroph Heterotroph Detritivore Gross primary production (GPP) Net primary production (NPP) Biogeochemical cycle Nitrogen fixation Chapter 55: Ecosystems You Must Know: How energy flows through the ecosystem (food chains and food webs) The difference between gross primary productivity and net primary productivity. The carbon and nitrogen biogeochemical cycles. Ecosystems Ecosystem = sum of all the organisms living within its boundaries (biotic community) + abiotic factors with which they interact Involves two unique processes: Energy flow Chemical cycling Overview of energy & nutrient dynamics Energy Flow in an Ecosystem Energy cannot .