ecological succession -- changes in the composition or structure of an ecological community

Ecological succession-- Changes in the composition or

structure of an ecological community

Types of ecological succession:

• Primary succession• Secondary succession• Seasonal (cyclic) succession

Successional modesPrimary succession

• Cataclysmic disturbance• Pioneer species are adapted to

extreme environments• Pioneer species make new soil

so that other plants can eventually live there too

Secondary succession• Ecological disturbance such as:

– Wildfire– Pollution– Storm

• Pioneer species colonize existing soil once inhabited by other species

Ecological succession

Minor ecological

disturbance

Period of gradual

ecosystem development

Period of gradual

ecosystem development

Primary succession

Secondary succession

Ecological equilibrium• Also called dynamic or climax equilibrium• Environment is in a relatively steady state• Biological invasion must occur through

competition alone

Example: Hawai’ian Islands

Ecological succession in Hawai’i• Chain of islands being

actively formed• Oldest and largest island is

the site of active volcanism

Ecological succession in Hawai’i• Chain of islands being

actively formed• Oldest and largest island is

the site of active volcanism (CATA_______ EVENT)

Ecological succession in Hawai’i• Chain of islands being

actively formed• Oldest and largest island is

the site of active volcanism (CATACLYSMIC EVENT)

Ecological succession in Hawai’i• Chain of islands being

actively formed• Oldest and largest island is

the site of active volcanism (CATACLYSMIC EVENT)

Ecological succession in Hawai’i• Chain of islands being

actively formed• Oldest and largest island

is the site of active volcanism (CATACLYSMIC EVENT)

• Species colonizing nearest the volcanoes are _______ SPECIES

Ecological succession in Hawai’i• Chain of islands being

actively formed• Oldest and largest island is

the site of active volcanism (CATACLYSMIC EVENT)

• Species colonizing nearest the volcanoes are PIONEER SPECIES– Algae, lichens, moss, fungi, grasses

Ecological succession in Hawai’i• Chain of islands being

actively formed• Oldest and largest island is

the site of active volcanism (CATACLYSMIC EVENT)

• Species colonizing nearest the volcanoes are PIONEER SPECIES– Algae, lichens, moss, fungi, grasses– Pioneer species make ____

• Chain of islands being actively formed

• Oldest and largest island is the site of active volcanism (CATACLYSMIC EVENT)

• Species colonizing nearest the volcanoes are PIONEER SPECIES– Algae, lichens, moss, fungi, grasses

– Pioneer species make SOIL

Ecological succession in Hawai’i

• Chain of islands being actively formed

• Oldest and largest island is the site of active volcanism (CATACLYSMIC EVENT)

• Species colonizing nearest the volcanoes are PIONEER SPECIES– Algae, lichens, moss, fungi, grasses

– Pioneer species make SOIL

Ecological succession in Hawai’i

PRIMARY SUCCESSION

• No cataclysmic events on older islands (Kauai, Oahu) in recent geologic history

Ecological succession in Hawai’i

• No cataclysmic events on older islands (Kauai, Oahu) in recent geologic history

• Species colonizing existing habitats are performing _________ SUCCESSION

Ecological succession in Hawai’i

• No cataclysmic events on older islands (Kauai, Oahu) in recent geologic history

• Species colonizing existing habitats are performing SECONDARY SUCCESSION

Ecological succession in Hawai’i

• No cataclysmic events on older islands (Kauai, Oahu) in recent geologic history

• Species colonizing existing habitats are performing SECONDARY SUCCESSION

Ecological succession in Hawai’i

Older islands are in a state of ECOLOGICAL ___________

• No cataclysmic events on older islands (Kauai, Oahu) in recent geologic history

• Species colonizing existing habitats are performing SECONDARY SUCCESSION

Ecological succession in Hawai’i

Older islands are in a state of ECOLOGICAL EQUILIBRIUM

Ecological succession in Hawai’i

________ SUCCESSION – Mauna Loa/Hualalai saddle, Big Island

Ecological succession in Hawai’i

PRIMARY SUCCESSION – Mauna Loa/Hualalai saddle, Big Island

Ecological succession in Hawai’i

___________ SUCCESSION – Kalaulau valley, Kauai

Ecological succession in Hawai’i

SECONDARY SUCCESSION – Kalaulau valley, Kauai