Ecological Succession Primary and Secondary

changes that occur in the types of species that live in an area. What is it? The normal GRADUAL (takes a long time) changes that occur in the types of species that live in an area.

Ecological Succession There are two main types of succession, primary and secondary. Primary succession is the series of changes that take place when there is no soil present. For example, after a volcano or destroyed coral reef. Secondary succession is the series of changes that take place when there is soil present. For example, after a fire, hurricane, flood, destruction by man, or tornado.  

Which one do you think takes longer? Answer Primary Succession Why? The rocks need to break down to make the soil before new species will grow

What Species Comes first? Pioneer Species These are the FIRST species to grow They can be different depending upon the area. Example: is it a forest, a pond, a wetlands….? AND- is it primary or secondary succession?

What makes the difference between primary and secondary succession? The key is whether there is soil already present or does the soil need to be made from broken down rock

Examples of Pioneer Species Pioneer- FIRST species to grow Mosses

Pioneer Species- FIRST Lichens-do not need soil to survive They can survive drought, extreme heat and cold, and other harsh conditions and start the soil building process.

Lichens produce a weak acid that eats away at the rock and breaks it down into soil

Pioneer Species- FIRST Algae- many types

Second Stage Second plants to become established after the disturbance (taller grasses, small shrubs). Shrubs

Third Stage- bushes Third species to become established

Fourth Stage- usually small trees; depends on ecosystem Fourth species to become established

Final Stage-Climax Community Last species to appear; some say it isn’t really finished growing.

Barren patch of land- just to see what can happen to a bare space!

Same patch of land two years later

Pond Succession- Primary or secondary? Put the pictures in order B, C, A, then D.

Disturbance- Forest Fire

Within 2 weeks, small grasses and other plants will grow- soil is already present

Second stage

Third stage

Full succession takes a VERY long time- could be 100’s of years. Still second stage/some small trees appearing

Succession in Action RestoringEarth - Educating People

When will the animal species return to the ecosystem? You must consider what is needed for them to be able to live in the environment. Animal species will not return until their needs can be met. What do they need? A habitat that will provide them with sufficient food, water, a hiding place, etc.

Choose your favorite disaster – how will succession occur? A disturbance: a forest fire a volcano a flood, dried up pond hurricane tornado abandoned ball field or tennis court coral dying for lack of water