Ecological SuccessionEcological Succession

Ecological SuccessionEcological Succession

• Definition of succession: The regular progression of species replacement in a changing ecosystem (= stages/steps of an ecosystem changing as different species replace others)

• http://www.blueplanetbiomes.org/climate.htm

Types of SuccessionTypes of Succession

• Primary Succession

• Takes place in areas that have not supported communities before or no life exists anymore

• Secondary Succession

• Takes place in an area that had once supported communities

Primary SuccessionPrimary Succession

• Starts with:– Bare Rock

– Lava Flows

– Sand Dunes

– Clear/cold Lakes

• http://www.hawaiipictures.com/pictures/volcano_lava.html

Primary SuccessionPrimary Succession

• First species to show up in the community is called the Pioneer Species

Lichens and Moss

Native Prairie Grass

SuccessionSuccession

• Each intermediate community that appears after the pioneer species is called a Seral Community.

• Each seral community alters the physical factors of the area

• May have small shrubs, start to have trees such as Jack Pine and Aspen

• May have small animals such as rabbits, squirrels, deer

SuccessionSuccession

• The last community to show up in an area is called the Climax Community.

• This community is stable and permanent. A state of homeostasis has been met.

• May have large trees such as Balsam Fir and White Spruce

• May have animals such as elk, bear, wolves, owls. http://www.blueplanetbiomes.org/deciduous_forest.htm

Secondary SuccessionSecondary Succession

• Usually occurs after a disturbance or natural disaster

• EX: fire, landslides, floods, wind, farming

• http://www.sover.net/~kenandeb/fire/hotshot.html

Primary Vs. Secondary Primary Vs. Secondary SuccessionSuccession

• Secondary Succession tend to develop faster because typically there is already a soil or nutrient base present – there may even be some seeds or other dormant life.

• Both types of succession go through similar phases of pioneer, seral, and climax communities.

Primary SuccessionPrimary Succession

Time

Small herbsand shrubs

Heath mat

Jack pine,black spruce,

and aspen

Balsam fir,paper birch, and

white spruceclimax community

Exposedrocks

Lichensand mosses

Fig. 8.15, p. 188

Secondary SuccessionSecondary Succession

Time

Annualweeds

Perennialweeds and

grasses

ShrubsYoung pine forest

Mature oak-hickory forest

Fig. 8.16, p. 189

Oligotrophic LakeOligotrophic Lake

• Succession of lake starts with a lake that does not have a lot of nutrients in it.

• Characteristics:– Cold, Clear water

– Support few Species

– Not much biomass• http://www.satirewire.com/news/july02/viagra.shtml

Eutrophic lakeEutrophic lake

• Process of adding nutrients to a water ecosystem is called Eutrophication. This results in a lake that

• has a lot of nutrients • Is Warm• Looks “Dirty” or “Cloudy”• Supports many species• Lots of Biomass

© 2003 John Wiley and Sons Publishers

Fig 10.7 Diagram of bog Fig 10.7 Diagram of bog succession.succession.