Chapter 5 – How Ecosystems Work Section 1 – Energy Flow in Ecosystems 1 – Life Depends on the Sun a – photosynthesis – plants use sunlight to produce sugar molecules – carbohydrates 6CO2 + 6H2O + SUNLIGHT C6H12O6 + 6O2 b – autotrophs – producers – makes its own food c – heterotrophs – comsumers – must consume autotrophs/producers

Chapter 5 – How Ecosystems Work EXCEPTION – deep ocean organisms that live off of bacteria that get their energy from hydrogen sulfide thermal vents 2 – What Eats What a – types of consumers - herbivores – eat only producers - plants - carnivores – eat only consumers – animals - omnivores – eat producers and consumers – plants and animals - decomposers – break down dead organisms

Chapter 5 – How Ecosystems Work 3 – Cellular Respiration: Burning the Fuel a – cellular respiration defined– breaking down food to produce energy C6H12O6 + 6O2 6CO2 + 6H2O + ENERGY 4 – Energy Transfer a – food chain – energy transferred from organism to organism b – food web – feeding relationships in an ecosystem c – trophic level – each step in a food chain or web

Chapter 5 – How Ecosystems Work b – energy pyramids – shows the loss of energy from one trophic level to the next - loss is equivalent to a factor of 10 - limits populations in each trophic level - producers, primary, secondary, tertiary consumers

Chapter 5 – How Ecosystems Work Section 2 – The Cycling of Materials 1 – The Carbon Cycle – carbon cycled between atmosphere, land, water, and organisms a – long term cycle - carbonates – shells, bones - limestone – rocks in the Earth – largest reservoir on Earth - burning of fossil fuels – releases CO2 that has been stored for millions of years

Chapter 5 – How Ecosystems Work 2 – Nitrogen Cycle – nitrogen cycled between the atmosphere, bacteria, other organisms a – nitrogen-fixing bacteria – take atmospheric nitrogen and convert it to a usable form for plants b – decomposers – break down dead matter a release that nitrogen back into the atmosphere

Chapter 5 – How Ecosystems Work 3 – Phosphorus Cycle – movement of phosphorus from the environment to organisms and back to the environment a – also long term b – erosion c – decomposition d - accumulation

Chapter 5 – How Ecosystems Work e - man made fertilizers affect the nitrogen and phosphorus cycles - overuse causes runoff - algal blooms f – burning affect the nitrogen and phosphorus cycles - increase if nitrous oxides in the atmosphere a – acid precipitation

Chapter 5 – How Ecosystems Work Section 3 – How Ecosystems Change 1 – Ecological Succession – gradual process of change and replacement of types of species in a community a – primary – occurs where no ecosystem existed before (example; new volcanic islands) b – secondary - occurs where an ecosystem previously existed - pioneer species – first in to a newly available area (example; old field succession) c – climax community – final and stable

Chapter 6 – Biomes Section 1 – What is a Biome? 1 – biome defined – a large region characterized by a specific type of climate and certain types of plant and animal communities – many individual ecosystems a – described by their vegetation - determines what animals live there

Chapter 6 – Biomes 2 – Biomes and Climate a – temperature – determines what plants live there b – precipitation – determines what plants live there c – latitude – distance from the equator - determines what plants live there d – altitude – distance above sea level – determines what plants live there

Chapter 6 – Biomes Section 2 – Forest Biomes 1 – Tropical Rain Forest – belt around the Earth near the equator a – warm, wet conditions b – rapid growth c- nutrients tied up in plants not soil therefore soil is not fertile d – layers - emergent layer – topmost - canopy – primary layer – tree tops

Chapter 6 – Biomes d – layers (cont) - understory – little light, very shady, shrubs & trees adapted to low light e – greatest species diversity f – highly threatened - wood - farm land - oil and mineral exploitation

Chapter 6 – Biomes 2 – Temperate Forests - North America, Australia, New Zealand a – high precipitation b – high humidity c – moderate temperatures 3 – Temperate Deciduous Forest – degrees north latitude a – broad leaf trees – birch, beech, oak, maple b – deep, rich, fertile soil

Chapter 6 – Biomes c – bears, deer, squirrels, migratory birds 4 – Taiga – northern coniferous forest, northern hemisphere just south of the Arctic Circle a – slow growing conifers b – short growing season c – wet during summer d – ideal for migratory bird breeding grounds, predators, large herbivores - bears, moose, elk, caribou

Chapter 6 – Biomes Section 3 – Grassland, Desert, and Tundra Biomes 1 – Savannas – tropical and subtropical – Africa, India, Australia, South America a – grasses, scattered trees, shrubs b – wet season and dry season c – grazing herbivores and their predators

Chapter 6 – Biomes 2 – Temperate Grasslands – grasses with few trees a – great plains of North American, steppes of Russia, pampas of South America b – prairie grasses, wildflowers c- grazing herbivores - bison, pronghorn sheet, antelope, prairie dogs, and their predators d – threats-farming and overgrazing

Chapter 6 – Biomes 3 – Chapparal – western North and South America, Mediterranean a – low evergreen shrubs – adapted to fire b – mule deer, coyotes c – threats - human development

Chapter 6 – Biomes 4 – Deserts – all continents with areas that receive less than 25cm of rainfall per year a – plants adapted to low rainfall - cacti - succulents b – animals tend to be nocturnal c – hot and cold

Chapter 6 – Biomes 5 – Tundra – north of Arctic Circle a – grasses, lichens, herbs, shrubs b – migratory birds, wolves, foxes, bears, caribou, deer c – threats - natural resource explorations - human intervention