Secondary succession is succession on land where a community has been removed or destroyed but the soil remains. Examples include land cleared by a forest fire, a flood, tree felling, or farmland that has been abandoned.Because soil is already present, secondary succession does not need the slow pioneer stage of lichens and mosses weathering rock. The soil already contains:• nutrients and humus
• seeds, spores and roots or rhizomes that survived
• decomposers and soil organismsThis means succession starts at a later seral stage, usually with fast-growing, opportunistic species such as grasses and annual weeds (for example on abandoned farmland). These are followed by perennial plants and shrubs, then fast-growing trees such as birch, and finally the climax community, which in much of the UK is deciduous woodland.As a result, secondary succession is much faster than primary succession. Abandoned arable land in the UK can develop into woodland within about a century, whereas primary succession on bare rock can take many hundreds or thousands of years.
As in primary succession, each seral stage changes the abiotic conditions, making the environment more suitable for the next group of species, and biodiversity and biomass increase over time.Key difference: primary succession starts with no soil; secondary succession starts with soil already present.
• seeds, spores and roots or rhizomes that survived
• decomposers and soil organismsThis means succession starts at a later seral stage, usually with fast-growing, opportunistic species such as grasses and annual weeds (for example on abandoned farmland). These are followed by perennial plants and shrubs, then fast-growing trees such as birch, and finally the climax community, which in much of the UK is deciduous woodland.As a result, secondary succession is much faster than primary succession. Abandoned arable land in the UK can develop into woodland within about a century, whereas primary succession on bare rock can take many hundreds or thousands of years.
As in primary succession, each seral stage changes the abiotic conditions, making the environment more suitable for the next group of species, and biodiversity and biomass increase over time.Key difference: primary succession starts with no soil; secondary succession starts with soil already present.