2CommunityCollection of several interacting populations that inhabiting a common environment.
3Abiotic factors and biotic factors determine an organisms ability to survive
4(food availability, temperature, and predators) Limiting FactorsEnvironmental factors that affect the organism’s ability to survive in its environment.(food availability, temperature, and predators)
5Limiting Factors Biotic or abiotic Restrict existence, numbers, reproduction or distribution of an organism.Factors that limit one population in a community, may indirectly effect anotherE.g. Lack of water limits grass growth—reducing seed growth, mice need seeds for food, no food, populations reduce.
6Ranges of ToleranceOrganisms ability to withstand fluctuations in biotic and abiotic environmental factorsPopulations varies according to its tolerance for environmental changes.
8SuccessionOrderly, natural changes and species replacements that take place in communities over time.
9SuccessionOccur in stages; different species at different stages create conditions that are suitable for some organisms and not suitable for others.Difficult to observe; happen over long periods of time.
10Primary Succession Initial colonization of new sites Lava from volcano; AvalanchePioneer species—First species in the area (e.g. Lichen)Climax Community—A stable, mature community that undergoes little or no change in species.Over time as a community or organisms change and develop (additional habitats emerge, new species move in, and old species disappear) Areas become forest of vines, trees, and shrubs, inhabited by birds and other forest-dwelling animals.Gradual changes over time.
12Pioneer species colonize Growth continues untilcommunity becomesfairly stable.Pioneering organism dies,decaying into soil.Presence of soil makesit possible for weedy plants,small ferns, and insects tobecome establishedSoil builds up,seeds borne by wind blow into soil,and begin to growArea becomes forest of vines,trees, and shrubs.Birds and other animals.
13Secondary SuccessionSequence of changes that take place after a community is disrupted by natural disaster or human actions.
14Secondary Succession Gradual changes over time Area previously contained lifeLand that contains SOILDifferent pioneer speciesMay have same climax community, with similar climate.Faster to develop because soil exist.
21Marine BiomesOceansPhotic Zone—Portion of marine biome that is shallow enough to penetrate sunlight (coastlines-Shore, beaches, mudflats)Aphotic Zone—Deeper waters that do not receive sunlight. (Deep, least explored oceans)Phos—Light (Greek)A—without (Greek)
26Estuary Bay, sound, fjord, salt marshes, wetlands Freshwater mixes with salt water (some land)Brackish Water ( more salt than freshwater; but less than marine)Salinity rangesAmount of freshwater vs.. SaltwaterTidesBiodiversity
27Estuary Life Eelgrass, smooth cordgrass, sea lavender Shiner Perch, Starry Flounder Orange Striped Jellyfish, Purple Shore Crab, ScallopPredators—cranes and other birdsDecay of dead organisms is quick, nutrients recycled through food web.
29Tides: Gravitational pull of sun and moon cause the rise and fall of ocean tides.
30Intertidal zone—Portion of the shoreline that lies between the high and low tide lines Size depends on slope of the land and tide height.High levels of sunlight, nutrients and oxygen (But productivity may be limited by waves/tides)Differ in rockiness and wave actionsSnails, sea stars, mussels, barnacles, clams, worms, crabs
31Tide Pools: Pools of water left when the water recedes at low tide, can land lock organisms until next tide. Vary greatly in nutrient and oxygen levels
33Ocean Bottom/Photic Zone Less affected by waves and tidesNutrients washed from the land by rainfall contribute to abundant life and high productivity.Plankton—Small organisms that live in waters of photic zone.**removal great impactAutotrophs—diatomsHeterotrophes—juvenile stages of many marine animals.
34Ocean Bottom/Aphotic Zone Almost 90 % of ocean is > than a km deep.Animals living there far and few, depend on photic zone where plankton live for food (directly or indirectly)Fish adapted to darkness and scarcity of food
36Freshwater Biomes Major abiotic factors: temperature and light Not enough sunlight penetrates to bottom to support photosynthesisfew aquatic plants or algae growPopulation density lowerBacteria break down dead organisms and recycle nutrients.
37Freshwater Life Concentric bands of species Cattails, sedges Tadpoles, aquatic insects, turtles, worms, crayfish, beetles, dragonflies, minnows, bluegill, carp.
45Taiga/Boreal Forest South of tundra Warmer and wetter than tundra Climatic conditions—long, severe winters, short, mild summers.Canada, Northern Europe, Asia.Permafrost absentTopsoil—decaying coniferous needles Pines/evergreens (acidic and poor in minerals)
46Taiga Organisms PLANTS Northern coniferous (cone bearing) forest Larch, fir, hemlock, spruce treesFire/Logging disrupts taiga-first trees to re-colonize are birch, aspen, or other deciduous species.ANIMALSRaccoons, bears, lynxes, wolves, ruff-legged buzzards, caribou, ox, artic fox
51Grasslands/Prairies/ Steppes/Pampas/Savannas Large communities covered by grasses and similar small plantsYellowstone National ParkFewer than 10 to 15 trees per HECTARE!(a unit of surface, or land, measure equal to 100 areas, or 10,000 square meters: equivalent to acres-www.dictionary.com)Most terrestrial areaHigher biological diversity than desert—more than 100 species per acre.
54Temperate Forests Many types Precipitation: 70 to 150 cm annually Dominated by broad-leaved Hardwood tress that lose their foliage annually.Soil—top layer rich in humus and deep layer of clay.Animals—Black bears, deer, squirrels, salamanders, mice, blue jaysPlants—birch, hickory, oak, beech and maple.
55Tropical Rain Forest More species of organisms anywhere Warm temperatures (25C), high humidity, and abundant rain fall, lush plant growthBiodiversity makes important protectNear equatorPrecipitation: 200 cm annually (some 600 cm)
56Why so many species in rain forest?: Hypothesis Location near equator—not covered with ice during last ice age—more time to evolveWarm weather, do not drop leaves, year round growing conditions for plants, creates greater food supply, therefore supports more organisms.Provide a multitude of possible habitats for diverse organisms.More layers allowing more for organisms to exist. (Many organisms find their niche)
57Tropical Rain Forest Continued Nutrients are tied up in living materials (few soil)Decomposers do their workRainforest trees have roots and mycorrhizae that enable them to absorb nutrients.Trees are cut for their hardwoods (mahogany), for farming, and to produce grasslands for cattle.
62CANOPYTrees : metersOnly a few taller trees push to make the emergent layerTreetops stop a lot of the light from entering the forest.Protects the soil from erosion from rains.Birds, monkeys, frogs, and sloth, as well as lizards, snakes and many insects
66SHRUB LAYERGrows between the smaller trees of the understory and the forest floor.ferns and small shrubs
67FOREST FLOORVery dark (Estimated that only 2% of the sunlight actually reaches the floor)Layer of leaves, twigs and dead plants, which rot down quickly to provide nutrients for the plants (Home to invertebrates and microorganisms, which quickly rot down this surface layer)The soil is very sandy with only a thin layer of rotting vegetation. Without the trees, the soil quickly loses its ability to support plants and turns to desert-like conditions.
68Rainforest floor Organisms Plants—Ferns and MossesAnimals—tigers and elephants in Asia, gorillas and leopards in Africa and tapirs and jaguars in South America.