- Slides: 44
Warm-up �What is ecology?
What is Ecology? • Ecology is the study of interactions between organisms and their environment
Ernst Haeckel • Coined term “Ecology” in 1866 – Greek word “oikos” means house – Why does this make sense?
Ecology Examples: • What kinds of studies could you do in Ecology? • How deer populations affect the undergrowth of forests • Oxygen content in lakes and ponds and how this affects fish and plants • How much will species diversity be reduced by the building of a new road in a forested area?
How do we study Ecology? 1) Observing • What species live here? How many are there? How do they interact? 2) Experimenting • Testing hypotheses to answer questions 3) Modeling • • Making models to investigate complex phenomena How will global warming progress in the next ten years? Twenty years?
Where do we study Ecology? • The Biosphere is the part of earth that supports life. This includes land, water, air, and the atmosphere • What on earth is NOT part of the biosphere?
Remember the 6 Characteristics of Life? ? ? • Can you name them? 1. Cells 2. Organization 3. Energy use 4. Homeostasis 5. Growth 6. Reproduction
Parts of the Environment Biotic: Living parts of the environment (animals, plants, fungi, etc. ) Abiotic: Non-living parts of the environment (air, water, sunlight, rocks, etc. )
How do we study such a large place? • Ecologists study many different levels of organization: • Species • Populations • Communities • Ecosystems • Biomes • Biosphere
Species § Group of similar organisms that can breed and produce fertile offspring
Population • A Population is a group of organisms in the same species that interbreed and live in the same area • Part of a population of bullfrogs:
Community • A Community is a mix of different populations that live together
Ecosystem • An Ecosystem includes the community and the non-living (abiotic)environment (soil, air, water, sunlight, etc. ) • The bullfrogs’ ecosystem is a pond:
Biome • A Biome is a group of ecosystems with the same climate and dominant communities • The Bullfrogs’ Biome is a temperate forest:
• The Bullfrog is a Species • They live in a Population with Bullfrogs • Their Community includes Bullfrogs and their biotic friends (birds, trout, trees) • Their Ecosystem is a pond, which includes abiotic factors (soil, air, water) • The Biome that they live in is the Temperate Forest • The Temperate Forest is part of the Biosphere In your notes, write your own level of organization (like we did for the Bullfrog). Start at the Species level and move up to an Ecosystem. You can use real or make believe organisms.
How do organisms interact with their environment? • Each organism has a habitat--where it lives out its life. There are many habitats in each ecosystem. • In habitats there are many niches, each occupied by one species. A niche is a species’ role, sort of like it’s JOB. • Why can there only be one species in each niche?
How do organisms interact with their environment? • Think of Finding Nemo and its examples of organism’s niches and habitats! – What is the Habitat? – What types of organisms do you see? – What are their niches? (what do they do? )
Autotrophs vs. Heterotrophs � Autotrophs – make their own food so they are called PRODUCERS � Heterotrophs – get their food from another source so they are called CONSUMERS
Warm-up �What is an autotroph? How do they get their energy? �What is a heterotroph? How do they get their energy?
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 Herbivores- only eat plants Carnivores - only eat animals Detritivores and Decomposers Feeds on plant and animal remains Omnivores- eat plants AND animals
How does Energy flow through an Ecosystem? � Energy flows through an ecosystem in ONE direction �sun or chemicals �autotrophs � heterotrophs
Energy Flow in Ecosystems:
Feeding Relationships � Food Chain – steps of organisms transferring energy by eating & being eaten � Food Web – network of all the food chains in an ecosystem
Food Web Trophic levels 3 rd/ top consumers 2 nd consumers 1 st consumers producers (notice the direction of the arrows!!)
Warm-up � Finish your American Shad Food Web. � On your warm-up sheet list the following from your American Shad Food Web: 1. 2. 3. 4. 5. Ultimate source of energy Producers Primary consumers (herbivores) Secondary consumers Tertiary consumers
Ecological Pyramids § Trophic Level – each step in a food chain or food web Biomass Pyramid Energy Pyramid of Numbers
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 � Most of the energy is used by the organisms for life processes � Some of the energy is lost as heat
Pyramid of Numbers – the number of individuals at each trophic level
Pyramid of Biomass - amount of living organic matter for each trophic level
How does Matter move through an ecosystem? � 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
Why are nutrients important ? � Every living organism needs nutrients to build tissues and carry out essential life functions. 95% of your body is made of… 1) 2) 3) 4) 5) OXYGEN CARBON HYDROGEN NITROGEN PHOSPHOROUS
Water Processes Precipitation: rain, snow, sleet, or hail (any water subject to gravity) � Evaporation: change of water from liquid to gaseous phase � Transpiration: evaporation of water from the leaves of plants � Run-off: water flow when the ground is saturated; causes flooding � Condensation: change of water from gaseous to liquid phase � Infiltration: process in which water on the ground enters the soil (opposite of run-off) �
THE HYDROLOGIC CYCLE
Carbon Cycle � Sources (release carbon �Breathing �Burning fossil fuels �Decomposition �Deforestation �Volcanoes � Sinks (take carbon �Photosynthesis �Oceans �Permafrost into the atmosphere) from the atmosphere)
Unusable form of nitrogen is in the atmosphere (N 2) Usable forms of nitrogen: 1) Ammonia (NH 3) 2) Nitrate (NO 3 -) 3) Nitrite (NO 2 -) ORGANISMS NEED NITROGEN TO MAKE PROTEINS!!! Video! NITROGEN CYCLE
Nitrogen Cycle 1. Bacteria and lightning “fix” nitrogen (take it in from atmosphere and make it usable) � Nitrogen fixation (nitrification) Bacteria and other organisms use the nitrogen 3. Plants absorb nitrogen through their roots 2. � Plants and animals use nitrogen to build proteins 4. Decomposers consume usable nitrogen and release unusable form (N 2) of nitrogen back into the atmosphere
PHOSPHORUS CYCLE PHOSPHORUS FORMS PART OF IMPORTANT LIFE-SUSTAINING MOLECULES (ex. DNA & RNA)
Availability of nutrients � If a nutrient is in short supply, it will limit an organism’s 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