Episode 03

OBJECTIVE :OBJECTIVE : After completing this After completing this unit, we will be able to compare, unit, we will be able to compare,

contrast and describe the contrast and describe the differences between primary and differences between primary and

secondary successionsecondary succession

CHANGES IN COMMUNITIESCHANGES IN COMMUNITIES

S U C C E S S I O N

The predictable changes that occur (happen) in a place over time . . . .

Primary Succession . -

The changes in an area where NO SOIL or ORGANISMS “ EXIST “

a new land comes out of the ocean

There is no soil at all – just lava rocks

NO PLANTS – NO LIFE

Then pioneer species comes from nothing

A new soil appears

Secondary Succession . -

• The series of changes that occur (happen) in a place or area where the Ecosystem has been disturbed by a disaster or human activities like :

• Fires – hurricanes – tornadoes – farming – mining – floods – volcanoes – earthquakes

• But where SOIL and ORGANISMS “ still ” EXISTS <<<<

DESTROYED ECOSYSTEM

SOIL AND ORGANISMS

STILL EXISTS

Secondary Succession may also happen arround your local area

• Just take a look on a vacant lot or an untendent place over time. Probably : first small grassy weeds grew, then larger weeds and some shrubs and finally small trees. Nature always finds a way to come charging back, like on that movie called “ I am Legend ” Do you remember how odd little plants push up through the pavement around New York city streets.

Secondary Succession

Observe how an untended city looks over the time

This movie is about a real succession possibility

Nature

Will always prevail

Let’s play with

volcanoeshttp://dsc.discovery.com/convergence/

pompeii/interactive/interactive.html