1	ECOSYSTEM Energy Flow Ecosystem studies measure the flow (movement) of Materials and Energy in Communities. Trophic, about or relating to nourishment
2	READING ASSIGNMENT Chapter 54 in Freeman Focus is on p.1243-1252. This lecture focuses on the flow of energy. The following lecture focuses on cycling of materials.
3	ENERGY versus MATERIALS The energy source of life on earth (the sun) is external to the earth. The amount of energy utilized by life is a small fraction of the available energy. The materials necessary for life are limited to what is on the earth. Materials must be recycled through various forms in the living and non-living world.
4	BASIC ENERGY FLOW SUN PRODUCERS (Autotrophs) CONSUMERS (Heterotrophs) Flow (flux) from one compartment to another
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6	Doing the SUMS of energy & material In studying energy flow we expect the inputs of a compartment to equal the outputs because energy is conserved. Matter is also conserved. In biological compartments inputs of material will equal the amount stored by the compartment plus the output into other systems/compartments.
7	Energy Flow Diagram
8	Measuring Energy E = m•c² units are g•m²•sec^-2 1 Joule = 1 kg•m²•sec^-2 1 calorie = heat necessary to raise 1 g of water 1° C = 0.239 Joule 1000 calories = 1 kcal = 1 Calorie Net Primary Productivity (capture of energy and materials) is often measured in grams of biomass per m² per year.
9	Productivity Gross primary productivity GPP is the amount of energy captured in photosynthesis (including that which is respired by the plant). Net primary productivity NPP is the amount of energy captured by the plant that remains in the plant (is available to consumers). Commonly measured in grams (dry) weight per square meter per year
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11	Productivity by Biome Though the productivity per unit area of the ocean is low, open ocean is so much more abundant than other communities that it is a big contributor to the earth’s total. Tropical forests and wetlands have the highest productivity per unit area of terrestrial communities.
12	CONSUMERS Consumers are heterotrophs dependent on reduced carbon compounds produced by autotrophs Consumers can be divided into three basic levels Herbivores organisms that eat plants Carnivores organisms that eat animals Decomposers organisms that utilize non-living reduced carbon compounds
13	Use of energy by consumers Efficiency of use into growth and reproduction varies greatly among species. OUTPUT Categories Growth and Reproduction Excretion (includes egestion) Respiration (used to generate motion) Measures of available energy based on living in oxygen atmosphere.
14	Use of Energy by a mammal
15	Carnivores Carnivores can be divided into Primary carnivores, animals that eat herbivores Secondary carnivores, animals that eat primary carnivores Tertiary carnivores are those that primarily get energy from secondary carnivores Carnivores that eat decomposers have no special name
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17	FOOD chains
18	Omnivore An animal that gains significant energy from more than one trophic level. Crayfish are omnivores. Many carnivores depend on plant products, especially fruit, for energy Bear Raccoon
19	A Detritus Food Web
20	Decomposer Food Web
21	Problem Use Figure 54.11 to calculate the NNP at Hubbard Brook Forest in kcal•m^-2•yr^-1. Convert the energy units to the conventional g•m^-2•yr^-1using the estimate of 4 kcal = 1g. Compare your value to the Figure 54.3 value for temperate deciduous forest.
22	Vocabulary Autotroph/producer Consumer/heterotroph Productivity Decomposer Herbivore Carnivore Omnivore Food web Respiration net primary production =NPP gross primary production =GPP Trophic level Joules