Features of Deciduous Woodlands (Edexcel GCSE Geography A)

Biotic & Abiotic Characteristics of Deciduous Woodlands

• Deciduous woodlands are found in the temperate climates of the northern and southern hemispheres

• They include Europe, eastern North America, parts of East Asia, southern Africa, Australia and New Zealand

• Deciduous woodlands thrive in mountainous areas and in regions with a range of soil types

• Deciduous trees shed their leaves in the cooler winters

Interdependence of Biotic & Abiotic Characteristics in Deciduous Woodland

• The deciduous woodland nutrient model shows that:

  • Biomass and soil stores are larger than the litter store

  • Deep tree roots break up the bedrock, and weathered rock adds those nutrients to the soil

  • Leaching is less significant in the soil store and soil fertility is higher due to mixing by earthworms 

  • The litter store is kept small due to rates of decomposition and lower levels of leaf litter

  • The rates of nutrient cycling is moderate

Deciduous woodland nutrient cycling

Energy flows

• The biotic and abiotic parts of the woodland are linked through nutrient cycle and food webs

• Producers include:

  • Tree species: elm, beech, oak and ash

  • Other plants: holly, fern, bluebells, and Wild Garlic

  • There are also lichens and mosses 

• Primary consumers include:

  • Insects

  • Rabbits

  • Deer

  • Squirrel (though they may eat larvae or caterpillars if conditions are harsh)

• Secondary consumers include:

  • Frogs

  • Voles

  • Fox

  • Badgers

• Tertiary consumers include:

  • Foxes

  • Birds of prey, such as sparrow hawks

Deciduous woodland food web

Interdependence 

• Trees, such as the rowan, rely on birds eating the berries to disperse their seeds

  • Some berries are dropped during flight to a new location

  • The seeds have an indigestible coating, which means that seeds which are eaten are deposited in droppings

• Oak trees rely on squirrels burying the acorns to store them for winter. Acorns, which are forgotten, germinate

• The trees in the woodland are mostly deciduous, which means that they lose their leaves, covering the ground with a thick layer, which then decomposes, adding nutrients to the soil

• A shrub layer of brambles, grass, bracken and other plants are the main producers

• Humans collect food and wood, which helps clear the forest floor

• In spring, before the trees come into leaf, more light reaches the woodland floor, allowing bluebells and daffodils to bloom

Deciduous Woodland Biodiversity & Adaptations

• Deciduous woodlands have lower biodiversity because

  • Summer has good levels of sunlight, but shorter days in the winter reduce nutrient cycling 

  • The ecosystem is smaller than the tropical rainforest

  • Lower temperatures and fewer sunlight hours in higher latitudes mean less photosynthesis

  • Growing season for 7 months of the year

  • Good nutrient levels in the autumn when leaves fall to supply the soil

  • No extreme temperatures (range: 4°C–17°C)

  • Rainfall (often frontal) is around 1000mm per year

  • Moderate humidity

Layers of a deciduous woodland

The distinctive feature of the deciduous woodland is the appearance and disappearance of the tree canopy during the season

• Deciduous woodlands have four layers

• The ground layer is often dark and damp, with brown earth soils around 30cm deep

• The herb layer consists of non-woody plants such as bluebells

• Under or sub-canopy with trees such as hazel and growing saplings

• The canopy layer has dominant trees around 20–35m high of oak, etc. 
  

• Deciduous trees also play a key role in water storage, provide habitats for animal hibernation, and are a source of food and a factor in bird migration

• Deciduous woodlands have four distinct seasons, forcing plants and animals to adapt

Plant and Animal Adaptation