We have studied how matter cycles through the 4 spheres, but how does energy cycle? Ecosystems

ECOLOGY- the study of organisms in their environment biosphere ecosystem community population organism

Essential question How does energy move through the ecosystem?

Ecosystem All the organisms in a community plus all the abiotic factors ecosystems are transformers of energy & processors of matter Ecosystems are self-sustaining, but what is needed? capture energy transfer energy cycle nutrients

Ecosystem inputs nutrients cycle inputs energy nutrients biosphere energy flows through constant input of energy nutrients cycle Matter cannot be created or destroyed Don’t forget the laws of Physics! nutrients can only cycle inputs energy nutrients

Generalized Nutrient cycling consumers consumers consumers producers decomposers decomposers nutrients ENTER FOOD CHAIN = made available to producers nutrients made available to producers return to abiotic reservoir Decomposition connects all trophic levels abiotic reservoir abiotic reservoir geologic processes geologic processes

Energy flows through ecosystems sun secondary consumers (carnivores) loss of energy loss of energy primary consumers (herbivores) producers (plants)

Food chains Trophic levels sun feeding relationships Tertiary consumer Trophic levels feeding relationships start with energy from the sun captured by plants 1st level of all food chains food chains usually go up only 4 or 5 levels inefficiency of energy transfer all levels connect to decomposers top carnivore Level 3 Secondary consumer carnivore Level 2 Primary consumer heterotrophs herbivore Level 1 Producer autotrophs Fungi Decomposers Bacteria

Inefficiency of energy transfer sun Inefficiency of energy transfer Loss of energy between levels of food chain To where is the energy lost? The cost of living! 17% growth energy lost to daily living only this energy moves on to the next level in the food chain 33% cellular respiration 50% waste (feces)

Ecological pyramid sun Loss of energy between levels of food chain can feed fewer animals in each level 1 100 100,000 1,000,000,000

Food webs Show in a more complicated way how energy flows A species may weave into web at more than one level