Ecological Succession

Succession is the term used to describe changes over time in the species that occupy a particular area.

Barren land:

• Glacier retreating and depositing rock
• Sand being piled into dunes by wind or sea
• Volcanoes erupting and depositing lava
• lakes or ponds being created by land subsiding
• silt and mud being deposited at river estuaries

Good Pioneer species e.g Lichens can withstand hostile environments with little water or mineral ions, germinate quickly, produce a vast quantity of wind-dispersed seeds. be able to photosynthesise, be able to fix nitrogen and tolerate extreme conditions. Overtime the lichens die which add mineral ions to the soil.

This soil is more suited to other species e.g Mosses, Ferns (secondary colonisers). When these die they add their mineral ions to the soil and the layer of soil becomes thicker which is able to support small flowering plants such as grasses, daisies and dandelions (tertiary colonisers).

Scrubland is when the area becomes colonised by shrubs. The roots grow deep into the land which stabilises the soil. which mean soil is less likely to be washed away by rain and can retain more water and mineral ions. eventually scrubland will give way to trees and become woodland. This is a climax community.

During succession:

• A greater number and variety of habitats
• Increases biodiversity
• More complex food webs
• Increased biomass

Conservation is the management of the Earth's natural resources so that maximum use of them can be made in the future.

Main reasons for conservation:

• Ethical
• Economic
• Cultural and asthetic

Managing succession-(Prevent change in next stage of succession)