Succession ends when a stable community is reached that does not change further as long as conditions stay the same. This is the climax community.Features of a climax community:
• It is in equilibrium with the climate and soil, and its species composition stays roughly constant over long periods.
• It is usually dominated by a few large species, the dominant species, which have most influence on the conditions. In a woodland these are the trees, which control how much light reaches the ground.
• It has a high biomass and complex food webs.
• Its type depends mainly on the climate. In most of the lowland UK it is deciduous woodland, dominated by oak (or beech on chalk). In the tundra it is low shrubs, mosses and lichens, because it is too cold for trees.Biodiversity often peaks in the stages just before the climax. At the climax, the dominant species may outcompete some other species, so the number of species can fall slightly.Plagioclimax. Human activity can stop succession before the natural climax is reached. This is deflected succession, and the community produced is a plagioclimax. Examples:
• Grazing by sheep or rabbits, or regular mowing, kills tree seedlings, so grassland remains.
• Burning heather moorland every few years prevents trees growing, keeping it as moorland.Conservationists sometimes manage plagioclimax habitats deliberately, because they support species, such as chalk grassland orchids, that would be lost if succession continued to woodland.
• It is in equilibrium with the climate and soil, and its species composition stays roughly constant over long periods.
• It is usually dominated by a few large species, the dominant species, which have most influence on the conditions. In a woodland these are the trees, which control how much light reaches the ground.
• It has a high biomass and complex food webs.
• Its type depends mainly on the climate. In most of the lowland UK it is deciduous woodland, dominated by oak (or beech on chalk). In the tundra it is low shrubs, mosses and lichens, because it is too cold for trees.Biodiversity often peaks in the stages just before the climax. At the climax, the dominant species may outcompete some other species, so the number of species can fall slightly.Plagioclimax. Human activity can stop succession before the natural climax is reached. This is deflected succession, and the community produced is a plagioclimax. Examples:
• Grazing by sheep or rabbits, or regular mowing, kills tree seedlings, so grassland remains.
• Burning heather moorland every few years prevents trees growing, keeping it as moorland.Conservationists sometimes manage plagioclimax habitats deliberately, because they support species, such as chalk grassland orchids, that would be lost if succession continued to woodland.