The 70% of the earth’s surface is covered by the ocean and the life inhabiting the
oceans play an important role in shaping the earth’s climate. Phytoplankton, also known as
microalgae, are the single celled, autotrophic components of the plankton community and
a key part of oceans, seas and freshwater basin ecosystems. They are significant factor in
the ocean carbon cycle and, hence, important in all pathways of carbon in the ocean.
Phytoplankton contain chlorophyll pigments for photosynthesis, similar to terrestrial plants
and require sunlight in order to live and grow. Most of them are buoyant and float in the
upper part of the ocean, where plenty of sunlight is available. They also require inorganic
nutrients such as nitrates, phosphates, and sulphur which they convert into proteins, fats,
and carbohydrates. In a balanced ecosystem, phytoplankton are the base of the food web
and provide food for a wide range of sea creatures (NOAA). The measurement of
phytoplankton can be indexed as chlorophyll concentration and is important as they are
fundamental to understanding how the marine ecosystem responds to climate variability
and climate change
