2.7 Ecological Succession

• Ecological succession is the process of change in the species structure of an ecological community over time
• Primary succession begins in areas where soil has already formed.

  False
• Match the type of succession with its starting environment:

  Primary Succession ↔️ Barren environments without soil

  Secondary Succession ↔️ Areas with existing soil but disturbed vegetation
• What type of species are common pioneer species in primary succession?

  Lichens and mosses
• Secondary succession occurs in areas where soil already exists but vegetation has been disturbed
• Steps in primary succession:

  1️⃣ Pioneer species colonize barren rock

  2️⃣ Soil formation begins through decomposition

  3️⃣ Intermediate communities develop

  4️⃣ Climax communities emerge
• What role do lichens play in primary succession?

  They break down rocks
• What are pioneer species in ecological succession?

  First organisms to colonize
• In primary succession, pioneer species such as lichens and mosses colonize newly exposed rock
• Lichens colonizing bare rock after a volcanic eruption is an example of primary succession.
• What is the role of lichens in primary succession?

  Break down rocks
• In secondary succession, pioneer species like grasses, shrubs, and fast-growing trees colonize areas where soil already exists
• Grasses sprouting after a forest fire is an example of secondary succession.
• Match the pioneer species with their type of succession:

  Lichens ↔️ Primary Succession

  Grasses ↔️ Secondary Succession
• What is ecological succession?

  Change in species structure
• Steps in primary succession

  1️⃣ Lichens colonize bare rock

  2️⃣ Lichens break down rock to form soil

  3️⃣ Mosses retain moisture and organic matter

  4️⃣ Foundation for future plant growth
• Secondary succession is faster than primary succession because soil is already present
• Grasses are pioneer species in secondary succession.
• What is a climax community in secondary succession?

  Stable forest or grassland
• What is the role of pioneer species in ecological succession?

  Stabilize soil and add nutrients
• Match the pioneer species with their role:

  Lichens ↔️ Break down rock

  Grasses ↔️ Cover bare soil
• What are intermediate communities in ecological succession?

  Transitional stages between pioneer and climax
• Intermediate communities stabilize soil and add nutrients to ecosystems.
• Shrublands in forests evolving from grasslands are an example of an intermediate community
• How does species diversity change from pioneer to intermediate to climax communities?

  Low to moderate to high
• What is a climax community?

  Stable, self-sustaining ecosystem
• Climax communities are characterized by high biodiversity and complex food webs.
• What is an example of a climax community?

  Old-growth forest
• Match the succession type with its characteristics:

  Primary Succession ↔️ Barren environment, slow process

  Secondary Succession ↔️ Existing soil, faster process