Mitcham Girls High School
Year 9 Science Project
ISS experiment

1

2

What is Phytoplankton?

Phytoplankton is a group of plankton species which contain chlorophyll and use photosynthesis to produce nutrients that are consumed by various other organisms. They play the same role in the ocean as plants do on land, by forming the base of the ecosystem. When thinking of marine life, most people think of fish or larger animals like whales. But, according to population, these only make up 2% of marine life and the remaining 98% is plankton, of which phytoplankton is a large part.
Changes in phytoplankton productivity and population could have a significant effect on a large variety of things, including biodiversity, fisheries, human food supply, and the pace of global warming. Due to this, monitoring it is essential.

The word phytoplankton is derived from the Greek words phyto (plant) and plankton (made to wander or drift). They are microscopic organisms, and mostly live in aquatic environments. Most phytoplankton are single celled and have many similarities to plants.4

(Not to scale)3
Significant declines in phytoplankton population have already been measured, most significantly in the North Atlantic and Indian oceans, where a 1% decline in diatom population has been observed 11. Further declines will most likely occur because these environments are under extreme threat from human activities such as oil drilling, overfishing, and pollution as well as Global warming.

Phytoplankton and the Food Web:

Phytoplankton makes up the basis of the marine ecosystem, which is also connected to the land animals. Phytoplankton is a producer, like plants, which means that a multitude of organisms, whales, zooplankton and jellyfish, depend on it directly for food. Depletion in phytoplankton population can lead to a decrease in populations of fish, problems in the fishing industry, and other industries that rely on marine life. This would also cause most marine species to go extinct, which would be catastrophic for people who rely on seafood to survive. Ultimately, all organisms need the nutrients created by the phytoplankton, and the entire food web would collapse if there was a major disturbance in phytoplankton activity.

4

Of course, too much of an increase of the wrong types of phytoplankton can be detrimental to the environment. A common example of this is algal blooms, infamous for their destructive effects, including the production of powerful bio-toxins that can poison humans and animals either by direct consumption, or via biological magnification4. By studying phytoplankton behaviour, we might gain insight into the nature of algal blooms, and may be able to predict and prevent these. A filter fine tuned to the correct wavelength might detect these, and we can observe patterns in blooms.

Carbon-oxygen cycle:

Photosynthesising organisms ensure the continuation of the carbon cycle and hence are crucial to the environment. Phytoplankton themselves consume enough carbon dioxide to match the amounts absorbed by trees and forests,and produce subsequent amounts of oxygen that are used by all organisms that depend on aerobic respiration. This carbon dioxide would otherwise accumulate in the atmosphere and eventually, suffocate all life-forms that require oxygen. This carbon dioxide is also a greenhouse gas, which forms a layer trapping heat in the atmosphere.

The ocean is a major carbon sink. The phytoplankton absorbs carbon, which is then carried to the deep ocean as the plankton die and sink down. Carbon is also transferred into other organisms which, in turn, consume other animals, reproduce and die. This ‘biological carbon pump’ means that 10 gigatonnes of carbon is transferred from the air into the deep ocean per year.4

These factors combine to regulate the amount of carbon dioxide in the air, and mitigate the effects of human pollution in the atmosphere. It also plays a part in controlling global temperature. The importance of this is growing steadily as human activities create increasing pollution and greenhouse gases.

But, this absorption of heat and carbon dioxide does mean that the ocean is heating up rapidly, and this can be fatal to the delicate ecosystem that is adapted to colder temperatures. Also, this can lead to the ocean currents changing patterns, which can have many unforeseen effects on humans. One example of the adverse effects of changing currents is the Gulf Stream which caused dramatic changes in the ice coverage of the Northern Hemisphere.14

15

All sources of heat give out infrared rays in varying amounts, and this infrared can be measured to determine the surface temperature at the point where plankton is being measured. This data can be mapped out and compared to the distribution of phytoplankton to gain insight into the correlation between the two.

What is Chlorophyll a?

Chlorophyll is the green pigment in all plants, which absorbs light and carbon dioxide. There are different types of chlorophyll, of which Chlorophyll A is the most common type, mostly found in marine plants and phytoplankton. Substances containing Chlorophyll A reflects wavelengths between 430 nm-662 nm of light, and this can be measured to estimate the abundance of phytoplankton in the ocean16. If we can measure this, and map out the data over time, we can detect patterns in plankton behaviour in relation to the temperature of the ocean.

7

What skills will we develop from this experiment, and how will we solve problems?

During this experiment we will develop the skills to plan, collect and analyse data. We will also gain skills in teamwork, problem solving, resilience and cooperation. To solve problems we will use a process of trial and error and also using mathematics and modelling.

How will we organise this experiment?

Our setup will require the specialised equipment required to produce clear sets of data. This includes several cameras and filters fine tuned to the wavelengths they are to measure, with a control camera which can help us record cloud, ice, wave and other conditions that might affect the results. An infrared camera will be used to measure temperature. All this can be controlled by a microcontroller, and connected on an Arduino board. The control program can control the cameras to take a photo and record the time as well as controlling the delay between pictures.We can then use the position of the ISS to find out the exact position over the ocean where the picture is taken. The data can be mapped out in a visual form, and then compared.

The visual form will make the data easy to understand for a large variety of people, including young children or amateurs which can help generate interest in marine life, space or species conservation as well as providing a clear, scientific format that can be used by professionals and in school environments.

Difficulties with the setup:

With the exact setup, we will face a few challenges, which will have to be resolved. These include finding the numerical required to code the control program, and the coding for any simulations we might have to carry out. We will also need to find out how large of a distance one image can take while maintaining a reasonable resolution.

The equipment itself will need to be bought and its size and weight must be taken into consideration. It will have to be protected from radiation and other harsh conditions in space. We will need to find out if the lack of gravity will affect our data, and how we could counter that. Choosing the cameras will also be a challenge, since we don’t want it to be too expensive, but still want quality materials that can withstand the pressures of space. We have calculated that the cameras, the memory and microcontroller will cost around AUD 200, and the power supply and filters will probably cost around AUD 300.

Possibly try 14 MP, USB_Shield_5 header board now is available from ArduCAM, it iscolour camera based on a ON-Semi (former Aptina) 1/2.3″ MT9F002 RAW RGB sensor.This camera header board provides low noise images for outstanding value in a broad range of industrial applications. It features a 15 megapixel (4608 x 3288) resolution imager capable of 6.3fps at full resolution, 30fps@1080p and 60fps@VGA resolution. These cameras header boardoffersthe user choice of 8-bit or 12-bit digitization parallel interface and a dynamic range of 60.5dB. It can work with USB Camera Shield seamlessly for fast evaluation, which provides SDK, API and examples for both Windows and Linux.

Hypothesis:

On a graph of phytoplankton population against ocean temperature, we expect to see a regular pattern, generally. The population will be minimal in freezing or boiling waters, and will rise in warm temperatures between 25 C and 35 C.

Of course, this graph will differ according to what area we measure and the species of plankton that exists. For example, phytoplankton nearer to the poles that are adapted to the cold temperature and lack of nutrients will have a larger population at, say, 5 C than at 40 C. Similarly, phytoplankton in a tropical environment will function better in warmer temperatures and will be resistant to the heat.

However, most phytoplankton will be adapted according to their location on the planet. So, each species will react differently to changes in temperature. So, we can monitor how each species reacts to different changes in ocean currents and temperature.

8

References:

  1. Sciencebuzz.org. (2017). microbes | Science Buzz. [online] Available at: [Accessed 12 Sep. 2017].
  1. Minks, C n.d., It's A Plankton Eat Plankton World, Arizona State University, Arizona, accessed 13 September 2017, <Askabiologist.asu.edu. Available at:
  1. Collage adapted from drawings and micrographs from Sally Bensusen NASA EOS project Science Office
  2. Simmon, R 2010, What are Phytoplankton?, Earth Observatory, accessed 12 September 2017, <
  1. Deviche, S. (2017). Plankton | ASU - Ask A Biologist. [online] Askabiologist.asu.edu. Available at: [Accessed 6 Sep. 2017].

Hansen, An.d., Invisible Watery World, ASU, accessed 12 September 2017, <

  1. Gran, S. (2017). New mission to study ocean color, airborne particles and clouds. [online] Climate Change: Vital Signs of the Planet. Available at: [Accessed 12 Sep. 2017].
  1. Hasen, A. (2017). Plankton | ASU - Ask A Biologist. [online] Askabiologist.asu.edu. Available at: [Accessed 6 Sep. 2017].
  1. Hanson, A 2011, An Invisible Watery Wall, ASU- Ask a biologist, accessed 1 September 2017, <
  1. DeviantArt. (2017). Plankton. [online] Available at: [Accessed 6 Sep. 2017].
  1. Lindsey, R. and Scott, M. (2017). What are Phytoplankton? : Feature Articles. [online] Earthobservatory.nasa.gov. Available at: [Accessed 12 Sep. 2017].
  1. NASA 2015, NASA Study Shows Oceanic Phytoplankton Declines in Northern Hemisphere, accessed 19 September 2017, <
  1. Earthobservatory.nasa.gov. (2017). What are Phytoplankton? : Feature Articles. [online] Available at: [Accessed 12 Sep. 2017].

13. Lindsey, R 2017, What are Phytoplankton?, accessed 6 September 2017, <

14. NOAA National Centres For Environmental Information n.d., Heinrich and Dansgaard–Oeschger Events, USA.gov, accessed 8 September 2017, <

15. Kurzgesagt - in a nutshell 2013, The gulfstream explained, online video, 11 October, accessed 20 September 2017, <

16. Gross, Jeana (1991).Pigments in vegetables: chlorophylls and carotenoids. Van Nostrand Reinhold,ISBN0442006578.

9