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Thirsty Land
Can you imagine a place without water that
can still sustain life? A place where temperatures can reach
120F, where the sun beats down relentlessly and it only
rains 1-3 years? There is such a place where both animals,
plants survive and even humans survive.
These are the large dessert areas of the world. How do
living things survive under such adverse conditions and how
do they adapt to make sure they keep enough water within
themselves to live? Desserts vary in the amount of rainfall
they receive some will only have rainfall every 1-3 years
and others every 3-6 months.
3 forms of life survive in the dessert.
· Plants
· Animals
· People
Today we will discuss desert plants. There are several ways
that plants have adapted to the desert.
· Cacti are the best-known dessert plants. They are
adaptations of the rose family, and are among the most
drought-resistant plants on the planet due to their absence
of leaves, shallow root systems, ability to store water in
their stems, spines for shade and waxy skin to seal in
moisture. Extensive shallow root systems are usually radial,
allowing for the quick acquisition of large quantities of
water when it rains. Because they store water in the core of
stems and roots, cacti are well suited to dry climates and
can survive years of drought on the water collected from a
single rainfall.
· By growing extremely long roots, allowing them to acquire
moisture at or near the water table. Phreatophytes, like the
mesquite tree, have adapted to desert conditions by
developing extremely long root systems to draw water from
deep underground near the water table. The mesquite's roots
are considered the longest of any desert plant and have been
recorded as long as 80 feet.
· Many desert plants adapt to the seasons of greatest
moisture and/or coolest temperatures. They remain dormant
during dry periods of the year, then spring to life when
water becomes available. They germinate only after heavy
seasonal rain. They complete their reproductive cycle very
quickly. They bloom prodigiously for a few weeks in the
spring, accounting for most of the annual wildflower
explosions of the deserts. Their heat and drought-resistant
seeds remain dormant in the soil until the next year's
annual rains.
· Many other desert trees and shrubs have also adapted by
eliminating leaves replacing them with thorns, not spines or
by greatly reducing leaf size to eliminate transpiration
(loss of water to the air). Such plants also usually have
smooth, green bark on stems and trunks serving to both
produce food and seal in moisture.
· Desert plants must act quickly when heat, moisture and
light inform them it's time to bloom. Ephemerals are the
sprinters of the plant world, sending flower stalks jetting
out in a few days. The peak of this bloom may last for just
days or many weeks, depending on the weather and difference
in elevation. The higher one goes, the later blooms come.
Different varieties of plants will be in bloom from day to
day, and even hour to hour, since some open early and others
later in the day.
· If you examine desert soils closely, you will dispel
forever any notion you might have of the desert as a barren
environment, for you will likely find dozens of both annual
and perennial seeds in every handful of desert soil.
As we marvel at the hidden life in desert soil and the
ingenious ways plants survive we may do well to reflect on
how important our water supplies are. Our planet’s whole
existence revolves around water. Let us learn to value this
simple commodity and look after our water sources.
Article written by Richard Deddy
Ric has had a full time business on the internet for over
six years. He is the owner and webmaster of
www.A1-Water-Distiller.com and http://www.HotGiftsandGags.com
He is the author of "The Changing Face of Civilization-Water
Quality and Your Life" and other articles. He is the
publisher of the A-W-D health newsletter.
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