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The Biosphere. Wakefield 2010-2011. What is Ecology?. What is Ecology?. The scientific study of interactions among organisms and between organisms and their environment or surroundings Comes from the Greek word “ oikos ” Means house. What is Ecology?.
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The Biosphere Wakefield 2010-2011
What is Ecology? • The scientific study of interactions among organisms and between organisms and their environment or surroundings • Comes from the Greek word “oikos” • Means house
What is Ecology? • Nature’s Houses / Ecological Levels of Organization Biosphere Biome Ecosystem Community Population Individual
What is Ecology? Levels of Ecological Organization
What is Ecology? • Species • A group of organisms so similar to one another that they can breed
What is Ecology? • Population • Groups of individuals that belong to the same species and live in the same area
What is Ecology? • Community • Assemblages of different populations that live together in a defined area
What is Ecology? • Ecosystem • A collection of all the organisms that live in a particular place Wetland Biome
What is Ecology? • Biome • A group of ecosystems that have the same climate and similar dominant communities Rain Forest Biome
What is Ecology? Biomes of the World
What is Ecology? Freshwater Biome
What is Ecology? Desert Biome
What is Ecology? Marine Biome
What is Ecology? Grassland Biome
What is Ecology? Savannah Biome
Field site Experimental plots, field sites, laboratory Many sites for data collecting Tapes, compass, Global Positioning System, thermometer, sensors Tapes, compass, Global Positioning System, thermometer, sensors Aerial views, Global Positioning System, weather balloons Binoculars, microscope, telescope Satellite images Binoculars, microscope, telescope Notes, automated data storage Notes, automated data storage Automated data storage Test kits Test kits Large database, multiple sensors Mathematical analysis and graphics, statistics Mathematical analysis and graphics, statistics Mathematical analysis and graphics, statistics, simulations Section 3-1 Compare/Contrast Table Ecological Methods Observation Experiment Model Building Sites Measuring Tools Magnifying Tools Written Record Chemical Testing Computer/ Calculators
Energy Flow - • Every organism must have energy • Earth’s energy source is the sun • Less than 1% of the earth’s energy is used by living things • Sun’s energy is transferred into organic energy through photosynthesis
Energy Flow - • Autotrophs – organisms that use energy from the environment to fuel the assembly of simple inorganic compounds into complex organic molecules • Producers – organisms that can make their own food • Capture energy from sunlight or chemical energy to produce their own food
Energy Flow - • Photosynthesis – process of using light energy to power chemical reactions that convert CO2 and H2O into O2 and energy rich carbohydrates such as sugars and starches
Energy Flow - • Chemosynthesis – process of using chemical energy to produce carbohydrates • Used by some bacteria • Volcanic vents • Tidal marshes • Extreme environments
Energy Flow - • Consumers / Heterotrophs – • Cannot harness energy directly from the physical environment • Must rely on other organisms for their energy and food supply • Consume the energy produced by the producers / autotrophs
Energy Flow - • Consumers / Heterotrophs • Herbivores – plant eaters • Carnivores – meat eaters • Omnivores – plant & meat eater • Detritovore – feed on the remains of plant and animals • Mites, earthworms, snails, crabs • Decomposer – breaks down organic matter • Fungi & bacteria
Energy Flow - • Feeding Relationships – • Energy flows through an ecosystem in one direction Sun / Inorganic matter Autotrophs Heterotrophs
Energy Flow - • Food Chains – the process by which energy is passed through the ecosystem
Energy Flow - • Food Webs – • Occurs when feeding relationships among the various organisms in an ecosystem form a network of complex interactions
Energy Flow – • Trophic Level – a step in the food chain or food web • Each level depends on the level below it for its energy • The first level of consumer depends on the producer • The producer depends on the inorganic environment • Secondary & tertiary consumers depend on the levels below them
Energy Flow – • Energy Pyramids – • A diagram that shows the relative amounts of energy or matter contained within each level of a food chain or food web • Energy Pyramid • Biomass Pyramid
Energy Flow – • Energy Pyramid • No limit to the # of levels that a food chain can support • Only part of the energy that is stored in one trophic level is passed on to the next level • Organisms use much of the energy they consume for their own life processes • Only about 10% of the energy of any level is available to be passed on to the next level
Energy Flow – • Biomass Pyramid • No limit to the # of levels that a food chain can support • Is based on the mass of the organisms at each level as well as the number of individuals at each level • There is always more mass at the lower levels that at the higher levels but not always more organisms
Cycles of Matter • Nutrient Cycles – (aka Biogeochemical cycles) • Recycles nutrients necessary for live • Water Cycle • All living things must have water to live • Carbon Cycle • Contained in all living things and in all nutrients • Nitrogen Cycle • Necessary for the building of proteins / and amino acids • Phosphorus Cycle • Necessary for the production of DNA & RNA • Hereditary materials
Water Cycle • All living things must have water to survive • Water is recycled between the ocean, atmosphere & land • Evaporation – Liquid to gas • Transpiration – Evaporating from leaves of plants • Condensation – Gas to liquid
Carbon Cycle • Carbon is the key ingredient of living tissue • CaCO3 in skeletons • Carbon is the key reactant in photosynthesis
Carbon Cycle • 4 Sources for Carbon in the environment • Biological processes • Photosynthesis • Respiration • Decomposition • Geochemical processes • Erosion • Volcanic Activity • Human Activities • Mining, cutting , burning of forests • Burning fossil fuels • Mixed biogeochemical processes • Burial, decomposition, conversion under pressure into coal & petroleum products (fossil fuels)
Carbon Cycle • Carbon is found in several large resevoirs: • Atmosphere as CO2 • Oceans as dissolved CO2 • Land in organisms, rocks & soil • Underground as coal, petroleum & calcium carbonate rock
Nitrogen Cycle N2 in Atmosphere NO3- and NO2- NH3
Nitrogen Cycle • All organisms require Nitrogen to make amino acids which in turn are used to build proteins • Nitrogen occurs in the biosphere in many different forms: • Nitrogen gas (N2) • Makes up 78% of our atmosphere • Also found in ocean water & other large bodies of water • Ammonia (NH3), Nitrates (NO3-), Nitrites (NO2-), • Found in dead and decaying organic matter • Also found in commercial fertilizers
Nitrogen Cycle • Nitrogen Fixing Bacteria – Only certain types of bacteria can effectively use nitrogen – They live in the soil and attach themselves to the roots of some plants where they convert ammonia to NO2 & NO3 • Consumers then eat the plants & use the nitrogen in the plant to make their own proteins Nitrogen Fixation
Nitrogen Cycle Denitrification
Phosphorus Cycle • Phosphorus is essential to living organisms • Forms part of the DNA & RNA molecules • Essential in the formation of genetic materials which carry the hereditary materials to offspring • Not common in the environment • Does not enter the atmosphere as do the other nutrients • Found in: • Rock and soil minerals • Ocean sediments • River sediments • Soil sediments
Nutrient Limitation • Nutrient – chemical substance that a living organism requires to live • H2O – Carbohydrates – Lipids – Proteins – Vitamins – Minerals • Limiting Nutrient – occurs when an ecosystem is limited by a single nutrient that is scarce or cycles very slowly • Nitrogen – Phosphorus – Potassium – Water • Algal Bloom – occurs when an aquatic ecosystem receives a large input of a limiting nutrient