Sometimes Even Algae Gets Sunburned

The pale color and white tips of this red algae is the result of too much ultraviolet radiation. (Photo Credit: Max Schwanitz, Alfred Wegener Institute)

The pale color and white tips of this red algae is the result of too much ultraviolet radiation. (Photo Credit: Max Schwanitz, Alfred Wegener Institute)

Plants and photosynthetic algae rely on the Sun as a source of energy to power photosynthesis. Without the Sun, these organisms would not be able to make the energy needed to perform the functions necessary for survive. However, there is such a thing as too much Sun. Similar to the sunburn you may get after sitting in the Sun too long, plants are also susceptible to overdoses of ultraviolet radiation.

When plants receive more light than they can use, light sensitive pigments used to absorb light for photosynthesis may become damaged. Overexposure to light may result in black spots, pale leaves, or rotten parts on the affected plant. Many plants and photosynthetic algae have developed strategies to deal with an excess of ultraviolet radiation.

For example, when a certain species of red algae receives too much ultraviolet radiation, the algae produces fewer red light-collecting proteins so that less radiation is absorbed. Outwardly, the algae turns a paler shade of red and forms white tips. In addition, the algae also produces mycosporin amino acids, a substance similar to melanin in humans. In humans, melanin absorbs ultraviolet radiation, protecting the skin from harm and forming a natural suntan.

However, due to the depletion of the ozone layer, more dangerous short-wavelength ultraviolet radiation is able to penetrate the Earth’s surface and seawater. The mechanisms that plants and photosynthetic algae have to protect themselves from ultraviolet radiation do not work well against these more harmful ultraviolet rays. In algae, the more dangerous ultraviolet radiation harms the organism’s ability to photosynthesize and negatively impacts the organism’s DNA. This damage leads to a much slower rate of growth and reduced reproductive success for the algae. Particularly sensitive are spores and algal gametes, for which even tiny doses of ultraviolet radiation are deleterious.

Researchers associated with the German French Research Base AWIPEV on Spitsbergen (a Norwegian island in the Arctic) have found that the distribution of certain species of algae are inhibited by ultraviolet radiation. They also found that as ultraviolet radiation increases, the algae are displaced into even deeper waters. According to the researchers, continued study of underwater algae is important as it illustrates how marine coastal ecosystems are being impacted by global climate change.

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  1. This article was very intresting.

  2. This was a very interesting article. I didn’t know that it was possible for algae to get sunburned.

  3. This was very interesting. I did not know that plants could get a sunburn. That explains why they are a light color sometimes.

  4. I found the article intriguing. I would never have thought the effect ultraviolet rays have on marine biology would be so drastic.
    (Ha. I didn’t use the word ‘interesting’ once.)

  5. Sarah [MVHS] says

    i knew a lot about photosynthesis before i read this article… when i think of photosynthesis i automatically think of the sun because it is key in this process…. but i didnt know there was such thing as “too much sun” for plants… this opened up new doors of information for me

  6. i thought that this was really interesting!!
    And i never knew that plants could get sunburned. Like the black spots and the rotten areas was just when you didnt water your plant!!!![=

  7. Shayna Ridley(MVHS) says

    it is crazy to think that life revolves around the sun! Without it we would not have plants and plants give us oxygen to breathe..But this article was very interesting and enjoyed reading it alot!

  8. trystanm cox !!!!! (mmhs)) says

    When I read this article I learned more about the sun and what it can do to plants.
    I knew that the sun could harm us but I had know idea that it could harm plants.
    I thought that it was interesting how plants can protect themselves, because they cant just walk into the shade like we can.

  9. Kiana (mmhs) says

    i never knew that algae could get sunburned

  10. Weston (MMHS) says

    it is very intresting how plants can be sunburnt and how they can protect themself they cant just move into a shaded area

    • plants actually can protect demselves, Weston. When a plant feelz lyke itz gettin too much sun 4 1 day it puts on a special type offf plant sunscreen callecd SunGoAway Plant Block.

      U should read da article on Here bout Sea Slugz. It real cool. I tink u would enjoy it very muchly.


  11. Breana Shockley [MMHS] says

    Mr. Chitraoff,
    This article really opened my eyes to plants. I always thought that they were the lucky ones because they never got sunburned. They can’t just move over to the shady spot like we can!

  12. WOW! This is amazing!

  13. I found this article weird.

  14. this article made me cry… 🙁

  15. this was cool :O

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