Presentation on theme: "Succession Ecosystems are NOT static, they are constantly changing"— Presentation transcript:
1Succession Ecosystems are NOT static, they are constantly changing Natural forces and human activity disturb themEcological succession - series of changes that occur over time in an ecosystemOrganisms occupy a site & change the environment so that other organisms can come inTwo Types:Primary successionSecondary succession
2Primary SuccessionPrimary succession - happens on surfaces where no soil exists (lifeless ground).Examplesafter a volcanic eruptionafter a glacier melts
3Primary Succession Steps 1. Pioneer species arrive (lichens): don’t need soil to survive2. Lichens die & decompose organic matter mixes with rock to start making soil3. Mosses & ferns can grow in new soil die & add more nutrients to soil4. Grasses & wildflowers can move in die & add more nutrients to soil5. Shrubs & trees can survive6. End in Climax community
4Pioneer speciesClimax CommunityFirst set of species to establish themselvesGrow rapidlyShort livedDo well in bright sunlight where nutrients are abundantSeeds are widely and rapidly disbursedlots of hardwoodshade-loving trees
6Secondary SuccessionSecondary succession – ecosystem is disturbed but soil is not removed (previous ecosystem remains)Examplescleared farming fieldsforest firesfloodtornadoSoil & seeds still present, so takes shorter amount of timeStart with grasses herbs, shrubs, small trees hardwood trees (climax community)
8Succession Time Line ***Be sure to label each picture Primary SuccessionSecondary SuccessionStart with a picture that represents a natural occurrence that would wipe out top soil. Ex: fire, mudslide, deforestationStart with weedsShrubs/ bushespinemature hardwoodsStart with a picture that represents a natural occurrence that would wipe out top soil. EX: erosion, glacier movement, volcanic eruption.Rocks or Earth’s crust with no top soil.Pioneer SpeciesSmall shrubs/bushesPinesMature hard woods***Be sure to label each picture
9When finished, write 2 paragraphs on your construction paper to describe the following: Paragraph # 1: Primary SuccessionExplain the steps of succession.What traumatic events would cause this re-growth to occur?What are pioneering plants? What are some examples of these?Explain why this type of succession takes longer than secondary.Paragraph #2: Secondary SuccessionExplain the steps of secondary succession.Why would pioneer plants not be needed?What do secondary successions have that primary successions do not?