What is the organization of Ecological Study? Population Community Ecosystem Biosphere Organism
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
IN AN ECOSYSTEM: Organisms live in a Habitat Organisms fit into a Niche of the environment
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.
Community Interactions when organisms live together in an ecological community they interact constantly. Three types of interactions –Competition –Predation –Symbiosis
Competition- competing for resources occurs due to a limited number of resources Resource- any necessity of life. water, nutrients, light, food. Competitive exclusion principle- no two species can occupy the same niche in the same habitat at the same time
Predation Predation- when an organism captures and feeds on another organism. Predator- hunter Prey- hunted
Symbiosis Symbiosis- any relationship where two species live closely together. (3 types) –Mutualism –Commensalism –Parasitism
Symbiosis Mutualism- both species benefit from a relationship. Lichens (fungus and Algae) One example is the lichens, little non-descript patches of stuff you see growing on rocks and tree bark. This is a symbiosis, consisting of a fungus and an alga. The fungus provides a protective home for the algae, and gathers mineral nutrients from rainwater and from dissolving the rock underneath. The alga gathers energy from the sun. There are thousands of species of lichen in the world; actually thousands of species of fungi with just a few species of algae which can form a partnership with almost any of them.
Symbiosis Commensalism – One member of a symbiotic relationship benefits and the other is neither helped or harmed Ex. Holes used by bluebirds in a tree were chiseled out by woodpeckers after it has been abandoned.
Symbiosis Parasitism- One creature benefits and one creature is harmed Ex tapeworm. Feeds in a humans intestines absorbing his/her nutrients.
Relationships: Symbiosis = Living Together a) commensalism b) mutualism c) parasitism
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 Web- A network of feeding relationships. (More realistic that a food chain) Food Chain- a series of steps in which organisms transfer energy by eating or being eaten.
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 next- most 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)
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
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 cell) 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
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 GUANO FERTILIZER ROCKS LAND FOOD WEBS DISSOLVED IN OCEAN WATER MARINE FOOD WEBS MARINE SEDIMENTS excretion weathering mining agriculture uptake by autotrophs death, decomposition sedimentationsetting out leaching, runoff weathering uplifting over geolgic time DISSOLVED IN SOILWATER, LAKES, RIVERS uptake by autotrophs death, decomposition
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
Pioneer stage Climax Community The trend of Succession
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 Deflection east and west
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
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
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-or- miss 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:
Rate at which a population could grow if it had unlimited resources If a population reached its biotic potential it would have exponential growth Biotic Potential = Reproductive Potential
The “S” Curve 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.
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 (100- acre) 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.
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.
Diversity & Conservation Importance to nature Importance to people –Oxygen –Diet –Medicines
Loss of Diversity Threatened Species Endangered Species Extinction of Species
Alabama -- 115 listingsAlabama Alaska -- 11 listingsAlaska Arizona -- 60 listingsArizona Arkansas -- 29 listingsArkansas California -- 300 listingsCalifornia Colorado -- 33 listingsColorado Connecticut -- 19 listingsConnecticut Delaware -- 20 listingsDelaware District of Columbia -- 3 listingsDistrict of Columbia Florida -- 111 listingsFlorida Georgia -- 66 listingsGeorgia Hawaii -- 317 listingsHawaii Idaho -- 25 listingsIdaho Illinois -- 28 listingsIllinois Indiana -- 29 listingsIndiana Iowa -- 14 listingsIowa Kansas -- 15 listingsKansas Kentucky -- 47 listingsKentucky Louisiana -- 26 listingsLouisiana Maine -- 15 listingsMaine Maryland -- 26 listingsMaryland Massachusetts -- 24 listingsMassachusetts Michigan -- 21 listingsMichigan Minnesota -- 13 listingsMinnesota Mississippi -- 38 listingsMississippi Missouri -- 25 listingsMissouri Montana -- 17 listingsMontana Nebraska -- 13 listingsNebraska Nevada -- 38 listingsNevada New Hampshire -- 12 listingsNew Hampshire New Jersey -- 23 listingsNew Jersey New Mexico -- 42 listingsNew Mexico New York -- 26 listingsNew York North Carolina -- 63 listingsNorth Carolina North Dakota -- 8 listingsNorth Dakota Ohio -- 26 listingsOhio Oklahoma -- 20 listingsOklahoma Oregon -- 54 listingsOregon Pennsylvania -- 17 listingsPennsylvania Rhode Island -- 17 listingsRhode Island South Carolina -- 42 listingsSouth Carolina South Dakota -- 12 listingsSouth Dakota Tennessee -- 96 listingsTennessee Texas -- 91 listingsTexas Utah -- 47 listingsUtah Vermont -- 8 listingsVermont Virginia -- 71 listingsVirginia Washington -- 41 listingsWashington West Virginia -- 21 listingsWest Virginia Wisconsin -- 16 listingsWisconsin Wyoming -- 18 listingsWyoming American Samoa -- 4 listingsAmerican Samoa Guam -- 12 listingsGuam Northern Mariana Islands -- 13 listingsNorthern Mariana Islands Puerto Rico -- 75 listingsPuerto Rico Virgin Islands -- 13 listingsVirgin Islands Outlying Caribbean Islands -- 0 listingsOutlying Caribbean Islands Outlying Pacific Islands -- 0 listingsOutlying Pacific Islands Endangered Species/State 2004 Data
Conservation Reintroduction Programs Captivity 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 (O 3 ) Depletion –O 3 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 CO 2 combines with water to form a weak acid H 2 CO 3 (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. 19701985
Humans & The Environment Global Warming –“The Greenhouse Effect” –Fossil fuels give off lots of CO 2 –This builds a blanket around the earth –It is predicted that the Earth temp. will increase ~5 0 C 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
Your consent to our cookies if you continue to use this website.