world biomes temperate deciduous forest. climate well-defined seasons with a distinct winter...

World Biomes

Temperate deciduous forest

Climate

• Well-defined seasons with a distinct winter characterize this forest biome. Moderate climate and a growing season of 140-200 days during 4-6 frost-free months distinguish temperate forests.

• Temperature varies from -30° C to 30° C.• Precipitation (750-1500 mm) is distributed evenly

throughout the year.

Distribution of biome

• Temperate deciduous forests occur in eastern North America, north-eastern Asia, and western and central Europe.

• Most temperate deciduous forests are found in Eastern North America somewhere around 35-48° N, and Europe and Asia around 45-60° N.

• There are some temperate deciduous regions in the southern hemisphere but their plants and animals are different from those of the northern deciduous forests.

Distribution

Soil• Brown forest soils develop

under the trees. Broadleaf trees tend to be nutrient-demanding and their leaves bind the major nutrient bases. The autumn leaf fall provides for an abundant and rich humus which begins to decay rapidly in spring just as the growing season begins. The humus content gives soil horizons a brown colour.

Plants I

• Summer is a busy time for deciduous trees.  Their broad leaves capture energy from the sun and convert it to food by photosynthesis.  Some of the food is used for growth and some is stored in the roots for next spring.  

• During the shorter days and cooler weather of autumn, green chlorophyll in the leaves begins to decompose, revealing brilliant oranges, yellows, and reds.  Actually, these colours were present in the leaves all year long, but had been hidden by the green pigment of the chlorophyll.  

Plants II

• To prepare for winter, deciduous trees and plants become dormant.  They loose their leaves and seal the places where leaves were attached with a protective covering called a leaf scar.  If they kept their leaves, the water in the leaves would freeze into ice, damaging the leaves and leaving the plant vulnerable to bacteria or fungi.  Plants also make a concentrated sugar solution to stop water from freezing in their stems.  

• The longer days and warmer weather of spring signal to the trees to grow new leaves and begin photosynthesis again. 

Oak

Sugar maple

Chestnut

Beech

Heather

Animals

• Precipitation in the temperate deciduous forest falls throughout the year. However, during the winter months it is usually frozen and less is available for animals to drink. Animals living within this biome must adjust to cold winters and hot summers by hibernating, migrating, or keeping active all winter. Leaves fall off trees here in the fall, leaving animals with less cover to hide themselves from predators. 

Racoon

Boar

Deer Marten

Golden oriole

Adder

People

• Human populations are quite high in this zone (which includes many of world's largest cities), fairly pleasant climatically and very productive of harvestable plant and animal life. Because the soil is excellent for agriculture, much of it has been cleared for a very long time all over the world for this purpose. In addition, hardwood trees are valuable for timber, so these forests were severely altered for thousands of years even before extensive farming.