Scientists Identify Conditions Necessary for Plant Growth on Mars
In a recent study presented by the United States Research Association (USRA) at the Astrobiology and the Future of Life conference on October 18, scientists outlined the atmospheric conditions required for planting trees on Mars.
Illustration of the terraforming process on Mars. (Image: Daein Ballard).
The research indicates that increasing the concentration of carbon dioxide (CO2) in the Martian atmosphere is a key factor in raising the planet’s temperature, thereby creating favorable conditions for plant growth.
The hypothesis of planting trees on Mars was proposed by Robert Olszewski, a professor at the Warsaw University of Technology in Poland. He and his colleagues examined the surface energy balance on Mars, specifically focusing on the heat exchange between the condensation and evaporation of CO2.
Interestingly, the conditions suitable for plant growth on the Red Planet are concentrated in areas other than the “tropical zone” as researchers typically expect.
“Surprisingly, the conditions that allow for plant growth do not first appear in the tropical zone (around 25°C) but rather in the Hellas basin. Increasing the greenhouse effect will expand the areas suitable for plant development,” the study explains.
Temperature map of the tropical region (±25°C) on Mars. The Hellas basin (marked) will be the first area to support plant growth. (Image: Olszewski/MOLA).
Using temperature and pressure data collected by the Viking Mars lander in the 1970s, Olszewski and his team simulated various processes occurring on Mars, both in the past and in future scenarios.
Olszewski and his colleagues assessed the total pressure required on Mars, acceptable percentages of CO2, necessary amounts of O2, available water, and the temperature range needed for plant growth to terraform the planet.
Among these factors, temperature is the most crucial when attempting to transform a planet. Temperature directly affects the amount of CO2 and the possibility of water formation.
“The temperature on Mars needs to be elevated by several degrees Celsius, while the temperature fluctuations between day and night must be significantly lower. For plant growth, the growing season must last at least 110 days on this planet,” the research indicates.
Furthermore, Olszewski and his colleagues note that on Earth, the highest density of vegetation is primarily found in tropical regions but is modulated by the position of the thermal equator.
“Thus, it can be predicted that the equatorial regions of Mars will be the first places to see the emergence of plants,” the scientist remarks.
However, due to the significant eccentricity of its orbit, the southern hemisphere of Mars experiences warmer summers when the planet is near the Sun. Additionally, one year on the Red Planet is equivalent to about 1.9 Earth years.
“Therefore, the long summers in the southern hemisphere provide the first suitable growing season for plants. Specifically, we found that the Hellas basin has the most favorable initial conditions,” the researchers conclude.
