HOW HAVE PLANTS ADAPTED TO DIFFERENT
BIOMES ACROSS THE WORLD?
Temperate deciduous woodlands
Tropical rainforests
Hot desert
How have plants adapted to different biomes across
the world?
Plants are everywhere and in every country. There are
millions of plant species and they are all essential to the
earth. Even though no plant is the same they all have one
thing in common- water, sun light and space are crucial for
survival. However, when these essentials are increased or
decreased, plants are forced to adapt to new surroundings.
There are three main types of biomes that they need to adapt
to. They are the tropical rainforest, deciduous forest and the
hot desert.
The tropical rainforests have the most diverse
population of plant species. Over 70% of plants in the
rainforest are trees. Many of the trees have straight trunks
that do not branch out for 100 feet or more; there is no point
in growing branches below the canopy because there is very
little light. A vast majority of the trees have smooth, thin
bark, as there is no need to protect them from water loss and
freezing temperatures. It also makes it difficult
for epiphytes and plant parasites to get a hold on the trunks.
With over 80 inches of rain per year, plants have made
adaptations that help them shed water off their leaves
quickly so the branches are not weighed down and break.
Some leaves have oily coatings to shed water. Some trees
have leaf stalks that turn with the movement of the sun so
they always absorb the maximum amount of light. Leaves in
the upper canopy are dark green, small and leathery to
reduce water loss in the strong sunlight.
Lianas are thick vines that climb trees, trekking
3000 feet up the sides of trees, trying to avoid being
hunted by dreaded loggers. They have thick woody
stems and vary in length and shape. They begin life on
the leafy floor, relying on the surrounding trees for
support as they begin their journey; they do this by
attaching themselves with sucker roots and growing with
other young sapling. Once the journey is complete, they
spread themselves onto other trees or join other Lianas who
have succeeded in the journey to find light.
Epiphytes forget about putting their roots into the
soil, instead they sink their roots into branches much
higher up. They grow everywhere, on tree trunks and
even leaves, mainly on branches. Epiphytes begin their
life in the canopy of the rainforest. They rely on being
transported by wind or birds.
Bromeliads are in the same family as the
pineapple. They have a thick waxy layer of leaves
that form a bowl shape, used for catching
rainwater; some can hold up to several gallons of
water at a time. They can be mini eco systems in
them selves. Bromeliads are home to frogs,
salamanders, snails, beetles and larvae. When the
animals die, they are decomposed and supply the
plants with nutrients.
Strangler figs send their long roots to
the ground; they choose their victim and start to
suffocate the poor tree within. Once the tree
inside has died and decomposed, an enormous
upright strangler fig is left in its place. By using
an adult tree as its host, the strangler tree
cleverly avoids competition for light and nutrients
on the ground level.
The rainforest is home to hundreds of different types of
adaptations. Here are a few more of them.
Rainforests have a shallow layer of fertile soil, so trees only
need shallow roots to reach the nutrients. However, shallow
roots cannot support huge rainforest trees; so many trees
have developed huge buttress roots. These stretch from the
ground to two metres or more up the trunk and help to
anchor the tree to the ground.
Another type of biome is a deciduous forest. Deciduous
forests 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. Deciduous trees usually have broad leaves e.g.
ash, beech, birch, maple and oak. In summers their broad
green leaves help capture sunlight needed to make food
through photosynthesis. They do not have a problem with
sunlight like the rainforest, because the leaves are much
smaller, more light can get to them.
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 photosynthesise causing leaves to
change to the beautiful red, yellow and orange leaf colours of
autumn. When the leaves fall from the tree, they are
decomposed into the soil by earthworms and other
decomposers. This makes the soil more fertile and gives it
nutrients.
In the winter, it is too cold for the trees to protect their
leaves from freezing, so they simply loose them. Before the
leaves die, some of the food material they contain is
absorbed 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. Some examples of trees and
plants in a deciduous woodland forest are:
Trees include Maple, many Oaks, Elm, Aspen,
and Birch. These are very common in typical deciduous
woodlands.
The hot desert is arguably one of the hottest and driest
places on earth. It is hard to imagine anything surviving there.
With the location very close to the equator, the daytime can
reach temperatures over 40 degrees, and at night can fall to
freezing. Therefore, plants must have a unique way of
surviving these massive drops in temperature.
Deserts have a limited range of plants that are able to
survive in their conditions, unlike other biomes, which have
unlimited numbers of plants.
The plants such as the cactus in the hot desert are
succulents. This means that they are able to store water in
their leaves, roots and stem. Plants have long roots that are
able to tap into water that is deep underground. They have
short life cycles; the plant will stop growing until there are
better conditions for them to continue their growth. They
have fewer leaves and more spines, not only do they offer
protection, they have a smaller surface area and this helps
reduce the amount of water lost. In addition, plants are
coated to keep the water on this inside instead of the out.
Plants are almost all ground-hugging shrubs and short woody
trees. All of the leaves are packed with nutrients. Some
examples of these kinds of plant are Turpentine Bush,
Prickly Pears, and Brittle Bush.
Therefore, biomes across the world are completely
different to one another. From the Amazon rainforest, the
Sahara desert and the deciduous woodlands of Europe there
is no doubt that each plant has cleverly adapted to their
surroundings. Avoiding the obstacles that Mother Nature
made has tested their skills to the limit. Some more than
others but nevertheless all of them are unique.