Energy and Flow

Energy Energy runs ecosystems It can typically be though of as food, or as materials used to make food. Nearly all energy related to ecosystems ultimately comes from our sun Energy Flow: transfer of energy between the organisms of a community

Capturing Energy Energy enters ecosystems when organisms capture it. What type of organism captures energy? Autotrophs (producers)- 2 types: Photoautotrophs- capture sunlight to construct simple carbohydrates Photosynthesis Chemoautotrophs- harvest energy from chemical bonds of inorganic moleucles chemosynthesis

Obtaining Energy After the energy is captured by the producers, it can be transferred/acquired by other organisms called…. Heterotrophs or Consumers Obtain their energy by eating other organisms- either producers or other consumers Energy flows from the sun to producers, the to various consumers The steps in which organisms transfer energy through a community is called a Food Chain

Food chains Feeding relationships Level 4 Tertiary consumer Sun Feeding relationships all food chains start with energy from the sun first level of all food chains is plants- producers Then herbivores/ omnivores Followed by omnivores/ carnivores most food chains go up only 4 - 5 levels all levels connect to decomposers Top carnivore Level 3 Secondary consumer Carnivore Level 2 Primary consumer Herbivore Level 1 Producer Fungi Decomposers Bacteria

Flow of Matter and Energy in Ecosystems Each feeding step in a food chain, or web is referred to as a trophic level Producers make up the first trophic level (base)- primary producers Consumers make up the higher levels. Primary consumers secondary consumers tertiary consumers quaternary consumers Each level relies on the one before it berries → mice → black bear

Trophic levels represent links in the chain

Food webs In most ecosystems, there are networks of complex, interconnecting food chains It is a more realistic view of the trophic structure of an ecosystem than a food chain

Energy Flow- not perfect When a zebra eats the grass, it does not obtain all of the energy the grass has (much of it is not eaten) When a lion eats a zebra, it does not get all of the energy from the zebra (much of it is lost as heat) The two (2) previous examples of energy transfer show that no organism EVER receives all of the energy from the organism they just ate Only 10% of the energy from one trophic level is transferred to the next – this is called the 10% law

Energy and trophic levels= Ecological pyramids show how energy flows through an ecosystem. Pyramids illustrate that the amount of available energy decreases at each succeeding trophic level. The total energy transfer from one trophic level to the next is only about 10% because organisms fail to capture and/or eat all the food energy available at the trophic level below them. Biomass is the total weight of living matter at each trophic level

Loss of energy Loss of energy between levels of food chain To where is the energy lost? The cost of living! 10-20% growth energy lost to daily living only this energy moves on to the next level in the food chain 30% cellular respiration 50% waste (feces)

Energy pyramid Loss of energy between levels of food chain fewer animals can live in each higher level There are always fewer animals in a level than the one previous Numbers 1 100 100,000 1,000,000,000

Biomass Pyramids Biomass= total amount of living tissue within a given trophic level Represent the amount of potential food in a particular level Resemble energy pyramids

Biomass Pyramid

But what about matter? n u t r i e s Energy flows through but nutrients and matter cycle nutrients must be recycled to be available for the next generation decomposers return nutrients to the soil after creatures die fungi bacteria decomposers

Nutrients cycle around… through decomposers consumers decomposers producers phosphorus potassium iron carbon nitrogen soil magnesium calcium

Biogeochemical Cycles Hydrologic Cycle Phosphorus Cycle Nitrogen Cycle Carbon Cycle

Hydrologic (Water) Cycle

Nitrogen Cycle

Nitrogen Cycme

Nitrogen Cycle

Phosphorous Cycle