Succession in Ecosystems

What is primary succession?

• The process of soil formation from bare rock

• The gradual replacement of one community by another in an ecosystem

• The development of a community in an area that has never supported life before

• The reestablishment of a damaged ecosystem where soil is already present

Which of the following is a characteristic of a climax community?

• It is the first stage of succession

• It is a stable and mature community with little change in species composition

• It is dominated by pioneer species

• It occurs only in areas with bare rock

What is the role of pioneer species in succession?

• They are the last species to colonize an area

• They modify the environment, making it more suitable for other species

• They prevent other species from colonizing the area

• They are only found in climax communities

Which of the following best describes secondary succession?

• It occurs in an area where no soil exists

• It begins in an area where a disturbance has destroyed a community but left the soil intact

• It is the initial colonization of bare rock

• It only occurs in aquatic environments

Tags

NGSS.MS-LS2-4

What is the first stage of soil formation?

• The accumulation of organic matter

• The weathering of rock into smaller particles (erosion)

• The establishment of a climax community

• The growth of large trees

Explain how pioneer species contribute to soil formation.

• They decompose and add nutrients to the soil

• They prevent erosion by covering the soil

• They consume nutrients from the soil

• They remove water from the soil

Tags

NGSS.MS-LS2-3

Compare primary and secondary succession in terms of soil presence.

• Both start with no soil present

• Primary succession starts with no soil, while secondary succession starts with soil present

• Both start with soil present

• Primary succession starts with soil, while secondary succession starts with no soil

Identify the sequence of stages in secondary succession.

• Bare rock, pioneer species, climax community

• Climax community, Disturbance, pioneer species, intermediate species, climax community

• Climax community, bare rock, soil formation, pioneer species

• Intermediate species, climax community, pioneer species

Why is the presence of soil important in secondary succession?

• It provides a surface for pioneer species to grow

• It contains nutrients necessary for plant growth

• It prevents water from accumulating

• It is not important; secondary succession can occur without soil

Analyze the impact of pioneer species on the environment during primary succession.

• They increase biodiversity immediately

• They create conditions that allow other species to establish

• They decrease the amount of sunlight reaching the ground

• They prevent other species from growing

Tags

NGSS.MS-LS2-3

NGSS.MS-LS2-4