3 G.2.1 Definegross productionTotal amount of energy trapped in organic matter produced by plants per area per time (kJ)net productionGross production – energy lost through respirationBiomassDry weight of an organism (g m-2 yr -1)
4 gross production – respiration = net production GP – R = NP G.2.2 Calculate values for gross production and net production using the equation:gross production – respiration = net productionGP – R = NPSample question!!Calculate % of energy moving up to herbivores
9 Food webs give more realistic image of ecosystem G.2.3 Discuss the difficulties of classifying organisms into trophic levels.Food webs give more realistic image of ecosystemOmnivores especially difficult--Depending on what eating, can be 1/2/3 consumer at different times
11 Higher trophic levels: low total biomass per unit area of ecosystem G.2.4 Explain the small biomass and low numbers of organisms in higher trophic levels.Top predators must be large enough to overwhelm their prey, so can only be relatively few of themHigher trophic levels: low total biomass per unit area of ecosystemBiomass lost during each TLevelCell respiration: biomass of glucose is lost, CO2, Water excretedEach successive level loses more and more biomass
14 Trophic Level Energy Flow (kJ m–2 yr–1) producers 20,810 G.2.5 Construct a pyramid of energy, given appropriate information. (Xref- pyramid of energy )Trophic Level Energy Flow (kJ m–2 yr–1)producers 20,810primary consumers 3,368secondary constertiary consumers
18 G.2.6 Distinguish between primary & secondary succession, using an example of each. CHANGE in abiotic and biotic factors in ecosystem over time...some species gradually replace others in a particular areaPrimary:Previously barren, lifeless areaNewly created volcanic islandPioneer species usually lichens—tolerant to extreme temp changes and little/no soil; they decompose rock...soil formsmoss can survive seeds germinate coconuts wash ashore, germinate; animals may swim/fly/carried on floats from other islands
19 Secondary: follows natural or artificial “upheaval” of the primary succession MUCH faster b/c soil already present, may be existing seeds & rootsEx. Forest firePrimarySecondaryBegins with no lifeFollows a disturbance of primary successionNo soilSoil presentNew area (volcanic island)Old area (following forest fire)Lichen & mosses pioneersSeeds & roots already presentBiomass lowBiomass higherProduction low (few plants)Production higher
22 Pioneer species to those that compete with others for nutrients G.2.7 Outline the changes in species diversity and production during primary succession.OVERALL TRENDS:Few species to manyPioneer species to those that compete with others for nutrientsLittle to high diversity (mature forest is home to 100s species)Simple relationships to more complex (mutualism, competition, predation)More & more biomass at each stage of succ.
23 G.2.7 Outline the changes in species diversity and production during primary succession. Foredune: no soil, only sand, p.succ. Starts here—lyme grass very salt tolerant, fast growing, roots stabilize dune; marram grass too, wide roots. LITTLE PLANT DIVERSITYYellow dune: developing thin layer of soil b/c yrs of m.grass; more plants invade (sedge, etc); rabbits here, nutrients from poop ; summer dandelions/thistle. Humus builds as pioneers decay. MORE COMPLICATED, MORE SPECIES, SOIL BEING FORMED
24 Mature dune: final stage of succession. Can support a forest G.2.7 Outline the changes in species diversity and production during primary succession.Grey dune: yrs of plants dying/decomposing, so layer of humus; it holds water; dune farther inland, less salt; thick shrubs eventually grow hereMature dune: final stage of succession.Can support a forestWild flowers, trees, mosses/ferns in shadeThick humus b/c 200 yrs of plants; high moisture contentMany insects, birds, mammalsCooler temp than foredune; less wind/blowing sand
25 Death/decay of plants/animals humus G.2.8 Explain the effects of living organisms on the abiotic environment with reference to the changes occurring during primary succession.soil developmentDeath/decay of plants/animals humusQuickly absorbs and releases water, good for plantsLeaf litter creates more org matter, mixes with sand, creates deep, well-draining soil; can support tall treesaccumulation of mineralsSand doesn’t hold moisture but humus & soil do, takes time to get structure to hold moisture and minerals to allow aeration of roots (structure IMPROVES)Bacteria, fungus (decomposers) active in recycling nutrients in soil w/humus (recycling INCREASES)reduced erosionRoots stabilize dune/soil, reduces erosion
27 G.2.9 Distinguish between biome & biosphere. Biosphere: living part of earth (where organisms live)Crust, atmosphereBiomes: divisions of biosphereEach is part of biosphereDefined by community structure and vegetation
28 PLOTS temp and rainfall in a region G Explain how rainfall and temperature affect the distribution of biomes.A climograph showing the biomes in G.2.11 can be used to illustrate the interaction between these two factors.PLOTS temp and rainfall in a regionTundra: organisms adapted to cold, dryConif forest: plants conserve water when ground frozen, animals heavy coats in winter (summer-shed)Temp forest: wide range of conditions (many deciduous to reduce water loss in winter)Desert: specific adaptations for extreme heat and dryness (kangaroo rat’s specialized kidney; cacti’s spines)Trop forest: high temp, high rainfall
29 G.2.11 Outline the characteristics of six major biomes. TempMoistureVegetationDesertMostly very hot. Soil temps >60C (140F) daytimeLow precip, <30cm/yrCacti, shrubs w/water storage tissues, thick cuticles & other water-loss adaptationsGrasslandCold winter temps;hot summersSeasonal drought; occasional fires; medium moisturePrairie grasses hold soil w/long roots; occasional fires prevent trees/shrubs from invading...and don’t forget the dead zebras. ShrublandMild winter temps;Long, hot summersRainy winters, dry summersDry woody shrubs killed by periodic fires; shrubs store food in fire-resistant roots; regrow quickly, produce seed that germinates only after fire!
30 G.2.11 Outline the characteristics of six major biomes. TempMoistureVegetationTemp Decid ForestVery hot summer, very cold winterHigh rainfall evenly throughout yr. Winter: water may freeze for short timeDeciduous trees (oak, hickory, maple) dominate. Warmer seasons—wide range of herbaceous plants on forest floorTropical rainforestVery warmVery high precip (>250cm/yr)Plant diversity very high. Canopy of top layer, next layer is shrubs; ground layer is herb.plants and ferns. Vines, orchids, bromeliads on trees.TundraVery cold;Summer-upper layer of soil thaws, but lower frozen (permafrost)Little precipitationLow-growing plants (lichen, mosses) and few grasses, shrubs. Permafrost prevents roots from growing deeply. Continuous daylight in summer allows plant growth & reproduction.
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