|Could we send species of plants to Mars, that
could survive on the Carbon Dioxide atmosphere?
|Question Date: 2018-01-06|
The carbon dioxide in Mars' atmosphere isn't
the problem: it's the fact that the atmosphere
is about 1% the thickness of the Earth's
atmosphere. With such a thin atmosphere, the
boiling point of water is below the freezing
point, which means that you can't have anything
living on the surface of Mars that requires liquid
water like a plant (or anything else).
We can take plants to Mars that would be able to
survive in the carbon dioxide, as long as the
plants are somewhat isolated such that they can
become self-sustaining by the oxygen they produce
as well. However, Martian soil, while having
all the nutrients that Earth plants need, are high
in perchlorates that are toxic to many organisms
from Earth. Without the perchlorates, the
soil from Mars would be able to support some
plants from Earth.
Provided you are not too restrictive with your
definition of plants, yes. Lichen (a sort of
composite plant/animal of algae and bacteria) was
survive for over a month in a simulated
Martian environment. These lichens were
particularly hardy though, and there are many
other issues which would complicate large-scale
vegetation growth, such as the dearth of water.
Although the atmosphere is predominantly
CO2, which plants might like, there
isn't much of it; the pressure of the Mars
atmosphere is only around 0.6% that of Earth's sea
level pressure. In addition, Mars is cold. While
the warmest days at the equator might reach 70°F,
the nights there can still be -100°F. Part of this
is due to the lack of an atmosphere to trap in
heat energy. Low light levels (depending on
latitude), various types of damaging radiation,
and potentially unsuitable soil conditions would
also impede progress.
Plants need really specific conditions to grow
beyond atmospheric requirements. They need
light, proper ratio of nutrients in the soil, and
stable environmental conditions. Mars is -80F
on average and even though it can get up to 70F
during the day near Mars’ equator, it can plummet
to -200F that night. A lot of plants would not be
able to withstand those temperature fluctuations.
Some of the nutrients in Mars’ soil would be
enough to support plant growth, but that really
depends on the region you design to plant on Mars.
Check this article out for more information:
The idea of transforming a planet to make it
more earth-like and thus more habitable to humans
is called “terraforming,” and was suggested
by Carl Sagan as early as 1961 for Venus. Venus
has an atmosphere that is rich in carbon dioxide
and so Sagan speculated about introducing
photosynthetic algae as a way to transform the
atmosphere. Unfortunately, Mars does not have much
carbon dioxide in its atmosphere. Mars is very
cold (no greenhouse gases), very dry (no liquid
water), and is constantly being bombarded by solar
UV radiation. Currently, no organism, not even
plants or algae or bacteria could survive the
harsh conditions on Mars. Mars today is very
different than the early earth, which had lots of
carbon dioxide, nitrogen, and water, and was warm
because of the greenhouse effect. All those
conditions are required for plants. Mars does have
a lot of frozen carbon dioxide and water in its
polar icecaps, so there is speculation that if
this could be melted and released, then this could
create an atmosphere around Mars that could
support plant life. One idea is to use giant
mirrors to reflect the sun’s rays into the Martian
icecaps to release the frozen carbon dioxide.
Once the temperature on Mars is warm enough
and there is enough carbon dioxide and water in
the atmosphere, then plants could do
photosynthesis and produce oxygen eventually
transforming the atmosphere to be similar to
earth. It is estimated that the overall process to
convert Mars to be habitable to humans would take
more than 100,000 years, and so most people are
not willing to wait that long.
Click Here to return to the search form.
Copyright © 2020 The Regents of the University of California,
All Rights Reserved.