SUCCESSION IN ECOSYSTEMS INTRO TO ENVIRO EXPO PART 4 DO YOU KNOW THESE WORDS??? To thrive, prosper, grow. To be accomplished - (a Succeed – success, to succeed at winning the game). To follow or replace another (like in an election) Thinking wild west – they were the first people Pioneer – to settle in the west. The early settlers. The peak of a story, the main event. Climax of a story – The conclusion. Primary – First Secondary - Second SUCCESSION - - a series of changes in a community in which new populations of organisms gradually replace existing ones http://www.dnr.state.mi.us/publications/pdfs/huntingwildlifehabitat/Landowners_Guide/images/vegetation/trees/forest_succession.gif SUCCESSION - Can take 100’s – 1,000’s of years to occur Each new community that arises makes it harder for the previous community to survive PRIMARY SUCCESSION- colonization of new sites by communities of organisms occurs on a surface where no ecosystem existed before (takes place on bare rock, cliffs, and sand dunes) PRIMARY SUCCESSION- New bare rock comes from 2 sources: Volcanic lava flow cools & forms rock Glaciers retreat & expose rock PIONEER ORGANISMS- - first organisms to colonize a new site and begin the process of ecological succession. ie: lichens are the first to colonize lava rocks . Look for moss and lichens – they will eventually break the rock down into soil, in which other plants Lichens are a fungus and usually an algae could grow. (symbiotic relationship) PRIMARY SUCCESSION - Rock CLIMAX COMMUNITY - -a stable, mature community that undergoes little or no succession Question(s): What other kinds of climax communities are there other than forests? Can there be such a thing? Yes. Marine communities, grasslands, etc. Whatever the final community is. CLIMAX COMMUNITY - FYI: In most of Virginia, the climax community would be a deciduous oak–hickory forest Question(s): Where in VA might it be something else? PRIMARY SUCCESSION - SECONDARY SUCCESSION - - sequence of community changes that takes place when a community is disrupted by natural disaster or human actions (takes place on existing soil) http://www.geo.arizona.edu/Antevs/nats104/00lect20sucn2.gif SECONDARY SUCCESSION - ie: A fire levels portions of a forest SECONDARY SUCCESSION - ie: A farmer plows his field Question(s): How many different kinds of secondary succession can you think of? List as many as you can. What about Mt. St. Helens? Is it primary or secondary succession? (Volcanic eruption in 1980) Maybe primary near the blast zone (where lava has flowed and harden into new rock/where there was no previous ecosystem) but Secondary further away (where some organisms survived the blast). http://www.olywa.net/radu/valerie/erupt.jpg SECONDARY SUCCESSION - POND SUCCESSION Ponds can become different ecosystems as times goes on (perhaps the climate changes and the pond dries out, therefore changing the ecosystem into more of a swampy/mucky area eventually changing into a non-aquatic environment, like a forest. POND SUCCESSION Question(s): Which would you classify this type of succession as: Primary or Secondary? Defend your answer..