Presentation on theme: "Modified by Beth Roland Jacobs Fork Middle School"— Presentation transcript:
1Modified by Beth Roland Jacobs Fork Middle School Ecology Unit- part 2Modified by Beth RolandJacobs Fork Middle School
2Biogeochemical Cycles (Matter moving through the environment) All living organisms need certain elements/compounds for life processesEx: your cells need Carbon,Hydrogen,Oxygen,Phosphorus,Nitrogen & Sulfur 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)
3Biogeochemical Cycles (Matter moving through the environment) The flow of a nutrient from the environment to living organisms and back to the environmentMain reservoir for the nutrient is in the environmentTransfer 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
4Three Categories Hydrologic cycle Atmospheric cycles WaterAtmospheric cyclesNitrogen and carbonSedimentary cyclesPhosphorus and sulfur
10Carbon in the OceansMost carbon in the ocean is dissolved carbonate and bicarbonateOcean currents carry dissolved carbon
11Carbon in Atmosphere Atmospheric carbon is mainly carbon dioxide Carbon dioxide is added to atmosphereAerobic respiration, volcanic action, burning fossil fuels, decomposition of organic materialsRemoved by photosynthesis
12Nitrogen CycleNitrogen is used in amino acids and nucleic acids (all living organism need nitrogen to make proteins)Main reservoir is nitrogen gas in the atmosphereDecomposers are vital to convert ammonia into:usable nitrites & nitrates for plants (nitrogen fixation)nitrogen gas (denitrification = puts it back into the atmosphere)
15Phosphorus CyclePhosphorus is part of phospholipids and all nucleotidesWhat are these? The basis of all DNA and cell membranesIt is the most prevalent limiting factor in ecosystemsMain reservoir is Earth’s crust; no gaseous phase (it never enters the atmosphere – like carbon and nitrogen)
16Phosphorus Cycle mining FERTILIZER excretion GUANO agriculture weatheringuptake by autotrophsuptake by autotrophsMARINE FOOD WEBSDISSOLVED IN OCEAN WATERweatheringDISSOLVED IN SOILWATER, LAKES, RIVERSLAND FOOD WEBSdeath, decompositiondeath, decompositionsedimentationsetting outleaching, runoffuplifting over geolgic timeMARINE SEDIMENTSROCKS
18Chapter 3 – Communities & Biomes Vocabulary to Know:Limiting FactorSuccessionPrimarySecondaryClimax Community
19Community All the populations that live together in a habitat Habitat is the type of place where individuals of a species typically liveType of habitat shapes a community’s structure
20BiogeographyThe study of the distribution of organisms and the processes that underlie distribution patterns
21Factors that Affect Distribution Geologic historyTopographyClimateSpecies interactions
22Climate Average weather condition in a region Affected by: amount of incoming solar radiationprevailing windselevation
23Rotation and Wind Direction Earth rotates faster under the air at the equator than it does at the polesDeflection east and west
24Seasonal VariationNorthern end of Earth’s axis tilts toward sun in June and away in DecemberDifference in tilt causes differences in sunlight intensity and day lengthThe greater the distance from the equator, the more pronounced the seasonal changes
25Ocean CurrentsUpper waters move in currents that distribute nutrients and affect regional climates
26Rain ShadowAir rises on the windward side, loses moisture before passing over the mountain
27BiomesRegions of land characterized by habitat conditions and community structureDistinctive biomes prevail at certain latitudes and elevations
36Exotic Species Example: Page 124 Non-native organisms that “move-in” to a particular areaThere can be a lack of competitors = exponential growthCan take over the niches of native species
37Conservation Sustainable use: Use what you need, but don’t damage the ecosystemIs this a good example of sustainable use?
38Humans & The Environment Ozone (O3) DepletionO3 forms a “good layer” around the EarthCFC release is breaking down the protective ozone layerUV rays increase skin cancers & other cell mutations to plants & animals!
39How is Acidity Measured? When we observe acid rain, acidity is measured in units called pH.The pH scale is from 0 to 14pH 7 indicates neutralhigher pH numbers = alkalinity (base)smaller numbers = acidWe’ll do more on pH in the “Biochemistry” chapter
40Natural 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 acidsLook at the “clean rain” – it’s already slightly acidic???
41Effects 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
43Humans & The Environment Global Warming“The Greenhouse Effect”Fossil fuels give off lots of CO2This builds a blanket around the earthIt is predicted that the Earth temp. will increase ~50C before 2050 = Ice age????
44Carbon Dioxide Increase Carbon dioxide levels fluctuate seasonallyThe average level is steadily increasingBurning of fossil fuels & deforestation are contributing to the increase
45Greenhouse EffectGreenhouse gases impede the escape of heat from Earth’s surface