What is Ecology? • Study of interactions betweenorganisms andbetween organisms and their environment. • Ernst Haeckel – coined term Ecology in 1866 • Greek word “oikos” means house • Natures “houses”come in many sizes
Levels of Organization • Ecologist study organisms ranging from the various levels of organization: • Species • Population • Community • Ecosystem • Biome • Biosphere
Organism Species • Group of similar organisms that can breed and produce fertile offspring
Population Population • group of organisms, all of the same species, which interbreed and live in the same area.
Community Community • an assemblage of different populations that live together
Ecosystem Ecosystem • Collection of organisms that live in a place with the nonliving environment
Temperate grassland Tropical rain forest Temperate forest Tundra Northwestern coniferous forest Mountains and ice caps Tropical dry forest Desert Temperate woodland and shrubland Tropical savanna Boreal forest (Taiga) Ecosystem Biome • Group of ecosystems with the same climate and dominant commuties
Ecosystem Biosphere • The part of the earth where life exists including land, water, air, and atmosphere
Three Ecological Methods of Study • Observing • What species live here? • How many individuals of species are there? • Experimenting • Used to test a hypothesis • Ex - making artificial environments in the lab • Modeling • Making models to gain insight into complex phenomena • Ex. - Global warming
Autotrophs – make their own foodso they are called PRODUCERS Heterotrophs – get their food from another source so they are called CONSUMERS Autotrophs vs. Heterotrophs
Two Main forms of Energy for Autotrophs • Sunlight • The main source of energy for life on earth • Photosynthesis • Chemical • Some organisms such as bacteria, rely on the energy stored in inorganic compounds • Chemosynthesis
Types of Consumers Omnivores Eat plants and meat Herbivores- only eat plants Carnivores - only eat meat Detritivores and Decomposers Feeds on plant and animal remains
How does Energy flow through an Ecosystem? • Energy flows through an ecosystem in ONE direction, • sun or chemicals • Autotrophs • heterotrophs
Food Chain – steps of organisms transferring energy by eating & being eaten Food Web – network of all the food chains in an ecosystem Feeding Relationships
Ecological Pyramids • Trophic Level – each step in a food chain or food web Biomass Pyramid Energy Pyramid Pyramid of Numbers
Pyramid of Biomass - amount of potential food available for each trophic level
Most of the energy is used by the organisms for life processes Some of the energy is lost as heat Pyramid of Energy - amount of energy available at each trophic level • Only 10% of the energy from each trophic level is passed on to the next level
Unlike the one way flow of energy, matter is recycled within & between ecosystems Nutrients are passed between organisms & the environment through biogeochemical cycles Biogeochemical Cycles: Bio –life Geo – Earth Chemo – chemical WATER CYCLE NUTRIENT CYCLES: CARBON CYCLE NITROGEN CYCLE PHOSPHORUS CYCLE How doesMatter move through an ecosystem?
95% of your body is made of… OXYGEN CARBON HYDROGEN NITROGEN Every living organism needs nutrients to build tissues and carry out essential life functions. Why are nutrients important ?
Availibility of nutrients • If a nutrient is in short supply, it will limit an organisms growth. It is called a limiting nutrient • When a limiting nutrient is dumped into a lake or pond, an algal bloom occurs and can disrupt the ecosystem
CARBON CYCLE (see fig.3-13) • 4 PROCESSES MOVE CARBON THROUGH ITS CYCLE: • Biological • Geochemical • Mixed biochemical • Human Activity CO2 CO2
NITROGEN CYCLE (see fig.3-14) N2 in Atmosphere • Nitrogen-containing nutrients in the biosphere include: • Ammonia (NH3) • Nitrate (NO3-) • Nitrite (NO2-) • ORGANISMS NEED NITROGEN TO MAKE AMINO ACIDS FOR BUILDING PROTEINS!!! N03- & N02- NH3
PHOSPHORUS CYCLE (see fig.3-15) PHOSPHORUS FORMS PART OF IMPORTANT LIFE-SUSTAINING MOLECULES (ex. DNA & RNA)