Climatic Climax in the British Isles: Temperate Deciduous Woodland
The climatic climax in the UK is known as Temperate Deciduous Woodland, which is a biome and an ecosystem. There are several recognised uses of temperate deciduous woodland: research area, provides habitats, open to conservation, help maintain the CO2 - O2 balance, help control temperature through albedo, recycle nutrients, maintain rainfall and humidity, anchor ground, regulate water flow, generate soil, and maintain groundwater level.
Climate:
Largely frontal rainfall, which is variable, averaging 500-1500mm per year. Precipitation reaches a maximum in the winter. Surplus of available moisture is derived from precipitation being greater than evapotranspiration. In the UK, milder winters are caused by the Gulf Stream (in comparison to similar latitudes elsewhere). There are also cool summers: around 15-20 degrees.
Soils:
Generally fertile due to leaf litter decomposition after annual leaf shedding. Nutrients are stored in the soil, which are mixed through the layers by earthworms. The soil type is known as Brown Earths.
Largely frontal rainfall, which is variable, averaging 500-1500mm per year. Precipitation reaches a maximum in the winter. Surplus of available moisture is derived from precipitation being greater than evapotranspiration. In the UK, milder winters are caused by the Gulf Stream (in comparison to similar latitudes elsewhere). There are also cool summers: around 15-20 degrees.
Soils:
Generally fertile due to leaf litter decomposition after annual leaf shedding. Nutrients are stored in the soil, which are mixed through the layers by earthworms. The soil type is known as Brown Earths.
Vegetation:
Dominated by 45-50m tall trees, of which the species depends on the soil characteristics:
· Acid soils: Birch and Rowan
· Alkaline soils: Box and Maple
· Both: Oak
· Clay: Lime and Elm
· Gleyed or Wet: Willow and Alder
Common for 1 or 2 species to dominate, however often around 40 species per hectare in North America. Deciduous trees shed leaves in winter to retain moisture (preventing desiccation), conserve nutrients and avoid damage by ice and snow. Net Primary Productivity (the amount of energy stored in plants after respiration) is high (around 1200g/m2/year) due to high summer temps and long daylight hours. As a result, biomass is also high; around 35kg/m2.
Light penetration can be limiting factor on lower surfaces:
· Heliophytes: plants that require light
· Sciophytes: plants that tolerate dark e.g. Dogs Mercury and Ivy
· Sycamore trees have large leaves and let little light penetrate
· Oak and Ash; less so – therefore allow a richer shrub layer and ground vegetation
· Layers closet to the ground have the greatest growth in Spring and early Summer e.g. Bracken, Grasses and spring flowering plants e.g. Bluebells
Nutrients:
Leaching can be high due to high precipitation, but balanced by fast weathering rates. Large store of nutrients in soil due to slow growth in winter, low density of vegetation in comparison to tropical rainforest and slow uptake of nutrients: about 25% as efficient as tropical rainforests.
Dominated by 45-50m tall trees, of which the species depends on the soil characteristics:
· Acid soils: Birch and Rowan
· Alkaline soils: Box and Maple
· Both: Oak
· Clay: Lime and Elm
· Gleyed or Wet: Willow and Alder
Common for 1 or 2 species to dominate, however often around 40 species per hectare in North America. Deciduous trees shed leaves in winter to retain moisture (preventing desiccation), conserve nutrients and avoid damage by ice and snow. Net Primary Productivity (the amount of energy stored in plants after respiration) is high (around 1200g/m2/year) due to high summer temps and long daylight hours. As a result, biomass is also high; around 35kg/m2.
Light penetration can be limiting factor on lower surfaces:
· Heliophytes: plants that require light
· Sciophytes: plants that tolerate dark e.g. Dogs Mercury and Ivy
· Sycamore trees have large leaves and let little light penetrate
· Oak and Ash; less so – therefore allow a richer shrub layer and ground vegetation
· Layers closet to the ground have the greatest growth in Spring and early Summer e.g. Bracken, Grasses and spring flowering plants e.g. Bluebells
Nutrients:
Leaching can be high due to high precipitation, but balanced by fast weathering rates. Large store of nutrients in soil due to slow growth in winter, low density of vegetation in comparison to tropical rainforest and slow uptake of nutrients: about 25% as efficient as tropical rainforests.
Animals:
Adapts to lack of food in winter: animals migrate, hibernate (e.g. bears), store food for winter (e.g. squirrels) and pigmentation (changes colour, e.g. stoats and weasels).
Humans Impacts:
Relatively widespread clearing of woodland and use of clearings for agriculture, where leaf fall is replaced by chemical or other organic fertilisers. Remaining forests are often heavily managed for recreation, conservation and economic exploitation, meaning few areas of natural forest remain
Adapts to lack of food in winter: animals migrate, hibernate (e.g. bears), store food for winter (e.g. squirrels) and pigmentation (changes colour, e.g. stoats and weasels).
Humans Impacts:
Relatively widespread clearing of woodland and use of clearings for agriculture, where leaf fall is replaced by chemical or other organic fertilisers. Remaining forests are often heavily managed for recreation, conservation and economic exploitation, meaning few areas of natural forest remain