Ecological Ecological SuccessionSuccession

SuccessionSuccession

Primary succession:Primary succession:development of a new community with development of a new community with

no previous life.no previous life.No No soilsoil is initially present. is initially present.Very slow!Very slow!

Examples:Examples:Bare rock, volcanic islandBare rock, volcanic island

Primary successionPrimary succession

1.1. LichensLichens colonize the bare rock. Lichens colonize the bare rock. Lichens are a mutualistic relationship between are a mutualistic relationship between fungi and algae.fungi and algae.

2.2. Dead and decaying lichen forms a layer Dead and decaying lichen forms a layer of of soil soil for grasslike plants to grow.for grasslike plants to grow.

3.3. Dead plants add to Dead plants add to organicorganic soil, so soil, so mossesmosses and larger plants can grow. and larger plants can grow.

Secondary successionSecondary succession

Existing community is cleared Existing community is cleared by a by a disturbancedisturbance, but soil is , but soil is present. present.

1.1. WeedsWeeds, like annual grasses, , like annual grasses, dandelions, colonize first. Seeds are dandelions, colonize first. Seeds are carried by wind or animals. Grow carried by wind or animals. Grow quicklyquickly, but , but diedie each year. each year.

2.2. PerennialPerennial grasses and shrubs colonize grasses and shrubs colonize later. Grow later. Grow slowerslower, but last longer., but last longer.

3.3. Large treesLarge trees, like oak, eventually , like oak, eventually colonizecolonize

Pioneer species: Pioneer species: firstfirst species species to predominate in succession. to predominate in succession. Tend to be Tend to be smallsmall, and grow , and grow quicklyquickly..

Climax community: Climax community: stablestable point that remains constant point that remains constant until a disturbance occurs. until a disturbance occurs.

SummarizeSummarize1.1. How are populations related to How are populations related to

communities?communities?

2.2. Describe the difference Describe the difference between a habitat and a niche.between a habitat and a niche.

3.3. An abandoned farm would be An abandoned farm would be an example of primary or an example of primary or secondary succession?secondary succession?