2. What is a Deciduous Forest?
The term deciduous forest is used to describe a type of forest in which the dominant
species of trees and other woody vegetation that make up the forest are those species
that shed their leaves during the cold months of the year and re-grows new leaves the
next spring in time for the growing season. Deciduous forests occur in several regions
throughout the world including eastern North America, the British Isles, eastern
Europe, New Zealand, eastern Australia, and northeast Asia. These regions though
diverse, share some characteristics. They all experience seasonal changes in temperature
and precipitation. As a consequence, the trees found in deciduous forests are specially
adapted to withstand these environmental changes throughout the year.
5. Plant adaptations
Deciduous trees are trees that shed their leaves once a year at the approach of a
cold or dry season and later grow new leaves. (Plants that keep their foliage
throughout the year are called evergreens.) Deciduous trees usually have broad
leaves e.g., ash, beech, birch, maple and oak.
In SUMMER, their broad green leaves help capture sunlight needed to make food
through photosynthesis.
As temperatures drop, the tree cuts off the supply of water to the leaves and seals
off the area between the leaf stem and the tree trunk. With limited sunlight and
water, the leaves are unable to continue producing chlorophyll (green pigment in
leaves) causing them to change into the beautiful red, yellow and orange leaf
colours of FALL.
6. In WINTER, it is too cold for the trees to protect their leaves from
freezing, so they simply loose them and seal up the places where the
leaves attach to the branch. Losing their leaves helps trees to conserve
water loss through transpiration. (Dried leaves continue to hang on the
branches of some deciduous trees until the new leaves come out.)
Before the leaves die, some of the food material they contain is drawn
back into the twigs and branches where it is stored and used the following
spring.
The warmer temperatures of SPRING signal to the trees that they can
grow new leaves again, and restart the cycle.
7. In the deciduous forest there are many flowers like the passion berry and the
blue lily. There are many other flowers but those are some of the main ones.
The Deciduous forest does not have much vegetation but there are many trees
that contain outrageous amounts of flowers. Animals need these trees because
they provide shelter and some use them for food and even water from the leaves.
The trees adapt to this forest by having thick bark barriers on the trees to keep the
animals out and the trees from dying.
9. Deciduous forests are closer to the equator than the coniferous forests of the tiaga, and so they have
a longer growing season. This gives the plants more time to produce food, and the forest yields about
6000 Kilocalories per square meter per year for animals to eat. These primary producers form the first
trophic level.
The trees in the deciduous forest shed their leaves in winter. This prevents their branches from being
broken by the weight of the snow, but also means that they have to grow leaves anew each spring. The
trees and shrubs produce flowers, seeds, and fruits, such as wild cherries and persimmons. Many of the
shrubs beneath the trees also produce fruit, such as huckleberries, blackberries, and thimbleberries.
below the shrubs there are wild flowers, clumps of grasses, and ferns.
Herbivores eat the leaves and fruits of the forest. Some of the animals that live in coniferous
forests also live here. Squirrels, small rodents, and deer find food in the deciduous forest, and other
plant eaters, including many birds and insects, are also members of the community of primary
consumers. These animals are on the second trophic level. These animals can use the 6000
Kilocalories per square meters per year produced by the plants, but the most of this energy is used up
in the processes of living, such as breathing, circulating the blood, growth, and reproduction. Only about
one tenth of the energy is stored in the bodies of the herbivores, so animals eating these herbivores can
only get 600 Kilocalories per square meters per year from
10. The small carnivores, the secondary consumers, form the third trophic level.
Many of these animals, such as woodpeckers and skunks, eat insects, while
others, such as racoons, foxes, and snakes, eat the small rodents and frogs. The
small carnivores have 600 kilocalories per square kilometer per year to
eat, but, again, nine tenths of these Kilocalories are used up in keeping the
animals alive. The bodies of the secondary consumers contain only 60 Kilocalories
per square meter per year.
This biome can support a fourth trophic level. Large carnivores, such as
bears and cougars, form a layer of tertiary consumers. These animals can eat
the larger herbivores, such as deer, as well as anything else in the biome.
However, only 60 Kilocalories per square meter are passed up to them from the
lower levels, so they have to be able to cover a lot of ground to be able to find
enough food to stay alive. Because these animals are at the top of the food
chain, they are called top predators.
ENDS..
