Ecology Unit Review Ecology the study of interactions between – organisms and organisms – organisms and their environment.
Download ReportTranscript Ecology Unit Review Ecology the study of interactions between – organisms and organisms – organisms and their environment.
Ecology Unit Review Ecology the study of interactions between – organisms and organisms – organisms and their environment Factors that effect us: 1. Abiotic Factors Moisture Wind/Air currents Light Temperature Soil ABio- stands for non stands for living Abiotic Factors- nonliving factors 2. Biotic Factors: living things What is the organization of Ecological Study? Organism Population Community Ecosystem Biosphere Levels of Organization Individual- one organism (living) Ex a moose Levels of Organization Population- groups of individuals that belong to the species and live in the same area. (living-living same species) Ex many moose Levels of Organization Community- groups of different populations (more than one population or different groups of species) Ex many groups of moose beavers, trees, grass (all living) Levels of Organization Ecosystem- all organisms in a particular area along with the nonliving. (living and nonliving) Ex many groups of moose beavers, trees, grass, rocks, water, mountains Levels of Organization Biome- group of ecosystems that have the same climate and similar dominant communities Biomes: tropical rain forest, tropical dry forest, tropical savannah, temperate grassland, desert, temperate woodland and shrubland, temperate forest, northwestern coniferous forest, boreal forest (taiga), tundra, mountains and ice caps Levels of Organization Biosphere- all of the planet where life exhists, includes land, water, and, air Life extends 8 km up and 11 km below the surface Habitat vs. Niche Habitat- an area where an organism lives Niche- an organisms role in its environment – The Long Version full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions. Includes where in the food chain it is, where an organism feeds Habitat is like an address in an ecosystem and a niche is like an occupation in an ecosystem. What is Succession & what causes it? Changes to a community Biotic Factor Abiotic Factors 2 Types of succession Primary – From nothing – Even the soil must be “created” Secondary – From soil – Disaster can strike and make it start over Primary Succession Secondary Succession Pioneer Species Species that colonize barren habitats Lichens, small plants with brief life cycles Improve conditions for other species who then replace them Climax Community Stable array of species that persists relatively unchanged over time Succession does not always move predictably toward a specific climax community; other stable communities may persist The trend of Succession Pioneer stage Climax Community Energy Flow (Trophic Levels) Producers- make their own food Consumers- get energy from consuming producers Producers Producers- capture energy from sunlight or chemicals and use the energy to produce food. Producers are autotrophs- they make food from their environment 2 main types of autotrophs One type gets energy from the sun-by photosynthesis Another type gets energy without light- by chemosynthesis Consumers Consumers are heterotrophs- get energy from other organisms Types of Consumers Herbivores- eat only plants Carnivores- eat animals Omnivores- eat both plants and animals Detritivores- eat dead matter (plants and animals) Feeding Relationships Energy flows through an ecosystem in one direction from: – – – – 1. the sun or inorganic compounds 2. To autotrophs (producers) 3. To heterotrophs (consumers) Decomposers get energy from decomposing dead organisms Food Chain- a series of steps in which organisms transfer energy by eating or being eaten. Food Web- A network of feeding relationships. (More realistic that a food chain) Food Web They can become very complex! Trophic levels Each step in a food chain or a food web is called a trophic level. – Producers are the first trophic level – Consumers are the second, third, or higher trophic level Each trophic level depends on the one below for energy Energy Pyramid Only part of the energy stored in one level can be passed to the nextmost energy is consumed for life processes (respiration, movement, etc., and heat is given off) Only 10% of the energy available within one trophic level is transferred to organisms in the next trophic level Biomass Pyramid Biomass- the total amount of living tissue within a given trophic level. A biomass pyramid represents the amount of potential food available for each trophic level in an ecosystem. Energy Losses Energy transfers are never 100 percent efficient Some energy is lost at each step Limits the number of trophic levels in an ecosystem Energy flow is a one way path! (not a cycle) G 1-3:List at least three things that will happen to the energy an animal consumes. 3 1 2 Energy Transfer 4. What percentage the consumed energy can be used for growth? All Heat in the End At each trophic level, the bulk of the energy received from the previous level is used in metabolism This energy is released as heat energy and lost to the ecosystem Eventually, all energy is released as heat Biogeochemical Cycles (Matter moving through the environment) All living organisms need certain elements/compounds for life processes – Ex: your cells need C,H,O,P,N & S in order to live and reproduce (make more cells) Cycles in nature keep these elements “moving” from organisms to organism (and sometimes into the atmosphere) Biogeochemical Cycles (Matter moving through the environment) The flow of a nutrient from the environment to living organisms and back to the environment Main reservoir for the nutrient is in the environment Transfer rates to and from reservoir are usually lower than the rates of exchange between and among organisms. Matter is recycled through an ecosystem – not one way flow Three Categories Hydrologic cycle – Water Atmospheric cycles – Nitrogen and carbon Sedimentary cycles – Phosphorus and sulfur CYCLES IN NATURE Carbon Cycle Carbon moves through the atmosphere and food webs on its way to and from the ocean, sediments, and rocks Sediments and rocks are the main reservoir Carbon Cycle diffusion Atmosphere Bicarbonate, volcanic action carbonate Marine food TERRESTRIAL webs ROCKS Terrestrial Rocks photosynthesis Land Food Webs Soil Water Marine Sediments weathering Peat, Fossil Fuels Carbon in the Oceans Most carbon in the ocean is dissolved carbonate and bicarbonate Ocean currents carry dissolved carbon Carbon in Atmosphere Atmospheric carbon is mainly carbon dioxide Carbon dioxide is added to atmosphere – Aerobic respiration, volcanic action, burning fossil fuels, decomposition of organic materials Removed by photosynthesis Nitrogen Cycle Nitrogen is used in amino acids and nucleic acids (all living organism need nitrogen to make proteins) Main reservoir is nitrogen gas in the atmosphere Decomposers are vital to convert ammonia into: 1. usable nitrites & nitrates for plants (nitrogen fixation) 2. nitrogen gas (denitrification = puts it back into the atmosphere) Phosphorus Cycle Phosphorus is part of phospholipids and all nucleotides – What are these? It is the most prevalent limiting factor in ecosystems Main reservoir is Earth’s crust; no gaseous phase (it never enters the atmosphere – like carbon and nitrogen) Phosphorus Cycle mining excretion FERTILIZER GUANO agriculture uptake by autotrophs MARINE FOOD WEBS weathering DISSOLVED IN OCEAN WATER uptake by autotrophs weathering DISSOLVED IN SOILWATER, LAKES, RIVERS death, decomposition sedimentation death, decomposition leaching, runoff setting out uplifting over geolgic time MARINE SEDIMENTS ROCKS LAND FOOD WEBS Community All the populations that live together in a habitat Habitat is the type of place where individuals of a species typically live Type of habitat shapes a community’s structure Biogeography The study of the distribution of organisms and the processes that underlie distribution patterns Factors that Affect Distribution Geologic history Topography Climate Species interactions Climate Average weather condition in a region Affected by: – amount of incoming solar radiation – prevailing winds – elevation Rotation and Wind Direction Earth rotates faster under the air at the equator than it does at the poles Deflects patterns at right into rotating currents Seasonal Variation Northern end of Earth’s axis tilts toward sun in June and away in December Difference in tilt causes differences in sunlight intensity and day length The greater the distance from the equator, the more pronounced the seasonal changes Ocean Currents Upper waters move in currents that distribute nutrients and affect regional climates Rain Shadow Air rises on the windward side, loses moisture before passing over the mountain Soil Characteristics Amount of humus pH Degree of aeration Ability to hold or drain water Mineral content Biogeographic Realms Six areas in which plants and animals are somewhat similar Maintain their identity because of climate and physical barriers that tend to maintain isolation between species Biomes Regions of land characterized by habitat conditions and community structure Distinctive biomes prevail at certain latitudes and elevations Biomes Biome Chart (to fill in during presentations) Create a Biome Table with the Following Columns: 1. Name of Biome 2. Major Location(s) 3. Avg. Temperature/climate 4. Avg. Rainfall – convert to inches 5. Major plant life 6. Major animals 7.Other – include things such as other major identifying factors of the biome, alternate names of the biome, limiting factors of the biome for plants/animals, etc. Note: To convert rainfall from cm to in = 1cm X .39 = in Biome Coral Reef Savannah Location Temp. Rainfall Plants Animals Other Chapter 4: Population Biology What is a population? What is exponential population growth? What happens to a population when it reaches its carrying capacity? How many mice are in the following population? Estimate! Ready SET Go! How many did you count? What is the best way to count them? SAMPLING Population Sampling Sometimes, the entire population to be studied is small enough for the researcher to include the entire population in the study. – This type of research is called a census study because data is gathered on every member of the population. Usually, the population is too large for the researcher to attempt to survey all of its members. – A small, but carefully chosen sample can be used to represent the population. – The sample reflects the characteristics of the population from which it is drawn Sampling Methods There are LOTS ways to sample a population including: – Biased sampling, Systematic sampling, Stratified sampling, Judgment sampling, Quota sampling, Snowball sampling, Counting method, Hit-ormiss method, etc… HOWEVER, the most common methods are: – Random and non-random sampling – Each gives you a “best estimate” of the population size Population Size Factors that affect: – Natality – Mortality/Fatality – Immigration – Emigration Population Growth Curves Explain what is happening to the populations below: Population Growth Curves Explain what is happening to the populations below: Biotic Potential = Reproductive Potential Rate at which a population could grow if it had unlimited resources If a population reached its biotic potential it would have exponential growth Exponential Growth Logistic Growth This graph shows a typical population growth curve. Under ideal conditions a population would have a growth with a slow start, then a very fast rate of increase and finally the growth slows down and stops. Predator-Prey Relationships: 1. 2. 3. 4. What happens if a population “booms” above carrying capacity? Who booms first during each cycle? Why?? Does a prey boom have to be followed by a predator boom? Population Density D Limiting Factors 1. Tend to reduce ________ rate or increase ________ rate. 2. Density-Dependent Factors, depend on population size: List • Competition for space, food, water, etc… • Predation: Gazelle-Cheetah, Deer-Wolf, Bison-Grass? • Parasitism and Disease • Waste accumulation 3. Density-Independent Factors: List • weather, seasons • natural disasters • human habitat disruptions Density Dependent Here is a dramatic example of how competition among members of one species for a finite resource — in this case, food — caused a sharp drop in population. The graph shows a population crash; in this case of reindeer on two islands in the Bering Sea. Inter or Intra? Density Dependent This graph shows the effect of interspecific competition on the population size of two species of paramecia, Paramecium aurelia and Paramecium caudatum. When either species was cultured alone — with fresh food added regularly — the population grew exponentially at first and then leveled off. However, when the two species were cultured together, P. caudatum proved to be the weaker competitor. After a brief phase of exponential growth, its population began to decline and ultimately it became extinct. The population of P. aurelia reached a plateau, but so long as P. caudatum remained, this was below the population density it achieved when grown alone. Density Independent This graph shows the decline in the population of one of Darwin's finches on Daphne Major, a tiny (100acre) member of the Galapagos Islands. The decline (from 1400 to 200 individuals) occurred because of a severe drought that reduced the quantity of seeds on which this species feeds. The drought ended in 1978, but even with ample food once again available the finch population recovered only slowly. Organism Interactions Limit Populations Predation Competition – Both types Parasitism Crowding/stress The Human Population Figure 4.10 pg 104 Demography Vocabulary Age Structure Immigration Emigration Birth/Death Rate Age Structure Pyramids These pyramids compare the age structure of the populations of France and India in 1984. The relative number (%) of males and females is shown in 5-year cohorts. Almost 20% of India's population were children — 15 years or less in age — who had yet to begin reproduction. When the members of a large cohort like this begin reproducing, they add greatly to birth rates. In France, in contrast, each cohort is about the size of the next until close to the top when old age begins to take its toll. Age Structure Pyramids These population pyramids show the baby-boom generation in 1970 and again in 1985 (green ovals). Profound changes (e.g. enrollments in schools and colleges) have occurred — and continue to occur — in U.S. society as this bulge passes into ever-older age brackets. Chapter 5: Diversity & Conservation Importance to nature Importance to people – Oxygen – Diet – Medicines Loss of Diversity Threatened Species Endangered Species Extinction of Species Endangered Species/State •Pennsylvania -- 17 listings •Rhode Island -- 17 listings •South Carolina -- 42 listings 2004 Data •South Dakota -- 12 listings •Maine -- 15 listings •Alabama -- 115 listings •Tennessee -- 96 listings •Maryland -- 26 listings •Alaska -- 11 listings •Massachusetts -- 24 listings •Texas -- 91 listings •Arizona -- 60 listings •Utah -- 47 listings •Michigan -- 21 listings •Arkansas -- 29 listings •Vermont -- 8 listings •Minnesota -- 13 listings •California -- 300 listings •Virginia -- 71 listings •Mississippi -- 38 listings •Colorado -- 33 listings •Washington -- 41 listings •Missouri -- 25 listings •Connecticut -- 19 listings •West Virginia -- 21 listings •Montana -- 17 listings •Delaware -- 20 listings •Wisconsin -- 16 listings •Nebraska -- 13 listings •District of Columbia -- 3 listings •Wyoming -- 18 listings •Nevada -- 38 listings •Florida -- 111 listings •New Hampshire -- 12 listings •American Samoa -- 4 listings •Georgia -- 66 listings •Guam -- 12 listings •New Jersey -- 23 listings •Hawaii -- 317 listings •New Mexico -- 42 listings •Northern Mariana Islands -- 13 •Idaho -- 25 listings listings •New York -- 26 listings •Illinois -- 28 listings •North Carolina -- 63 listings •Puerto Rico -- 75 listings •Indiana -- 29 listings •Virgin Islands -- 13 listings •North Dakota -- 8 listings •Iowa -- 14 listings •Outlying Caribbean Islands -- 0 •Ohio -- 26 listings •Kansas -- 15 listings listings •Oklahoma -- 20 listings •Kentucky -- 47 listings •Outlying Pacific Islands -- 0 •Oregon -- 54 listings •Louisiana -- 26 listings listings Threats to Biodiversity Habitat Loss Habitat Fragmentation – Biotic Issues – Abiotic Issues Habitat Degradation – Air Pollution – Water Pollution – Land Pollution Exotic Species Non-native organisms that “move-in” to a particular area There can be a lack of competitors = exponential growth Can take over the niches of native species Example: Page 124 Conservation Sustainable use: – Use what you need, but don’t damage the ecosystem Is this a good example of sustainable use? Conservation Habitat Corridors Conservation Reintroduction Programs Captive Breeding Example: The Ginkgo Tree would probably be extinct if it were not for Chinese monks keeping it in captivity around temples Humans & The Environment Pest Control – Benefits vs. Problems – EX: DDT Humans & The Environment Ozone (O3) Depletion – O3 forms a “good layer” around the Earth – CFC release is breaking down the protective ozone layer – UV rays increase skin cancers & other cell mutations to plants & animals! Humans & The Environment Acid Precipitation – In the form of rain, snow, dew or fog – Created when gases such as nitrogen oxide (NOx) and sulfur oxide (SOx), generated in the burning of fossil fuels such as coal and oil, react in the atmosphere with sunlight to produce acids such as nitric and sulfuric acid. These acids dissolve in rain to become acid rain. How is Acidity Measured? When we observe acid rain, acidity is measured in units called pH. The pH scale is from 0 to 14 – pH 7 indicates neutral – higher pH numbers = alkalinity (base) – smaller numbers = acid We’ll do more on pH in the “Biochemistry” chapter Natural Acid Precipitation CO2 combines with water to form a weak acid H2CO3 (carbonic acid) But we are adding to the problem… – by adding nitric and sulfuric acids Look at the “clean rain” – it’s already slightly acidic??? Effects of Acid Precipitation • In Japan, rain which registers pH 5.6 or less is considered acid rain; some 80-90% of the rain that falls in Japan in a year is acid rain. • In Japan, acid rain with acidity equal to lemon juice has been observed at Mount Tsukuba in 1984 (pH 2.5) and at Kagoshima in 1987 (pH 2.45). The problem is even more serious in North America and Europe. In those regions, forests are withering and lakes becoming uninhabitable to fish, and stone structures such as buildings and bronze statues are being damaged by corrosion. 1970 1985 Humans & The Environment Global Warming – “The Greenhouse Effect” – Fossil fuels give off lots of CO2 – This builds a blanket around the earth – It is predicted that the Earth temp. will increase ~50C before 2050 = Ice age???? Carbon Dioxide Increase Carbon dioxide levels fluctuate seasonally The average level is steadily increasing Burning of fossil fuels & deforestation are contributing to the increase Greenhouse Effect Greenhouse gases impede the escape of heat from Earth’s surface Global Warming Long-term increase in the temperature of Earth’s lower atmosphere Other Greenhouse Gases CFCs - synthetic gases used in plastics and in refrigeration Methane - produced by termites and bacteria Nitrous oxide - released by bacteria, fertilizers, and animal wastes