INTRODUCTION
6.1.1 Ecolog y of the Ocean
The world’s oceans cover about 71% of the surface of the
Earth and contain 97% of the planet’s water. The largest
portion of the ocean consists of the pelagic zone and
can reach depths of over 10 km (Figure 6.1). Most oceanic
research however is focused on the upper 200 meters of
the water column, known as the euphotic or epipelagic
zone, where enough light penetrates the water to enable
photosynthesis. The mesopelagic zone stretches from
200 to 1,000 meters below the surface. Together these
zones are home to the ocean’s primary producers, phytoplankton,
which are estimated to fix 40% of the atmospheric
carbon through photosynthesis (Falkowski, 1994).
They are the foundation of the oceanic food web and play
an important role in the structure of the pelagic system
(Adjou, Bendtsen, & Richardson, 2012). Therefore, phytoplankton
bycatch by The Ocean Cleanup Array, which will
interact with the surface part of the epipelagic zone, has
a potential effect on other marine organisms. Additionally,
removal of larger animals would also impact their
populations and local ecology in a more direct way.
Figure 6.1 Overview of oceanic divisions. The Ocean Cleanup Array will float on the surface, affecting the photic zone (0 - 200 m) directly.
Image from Wikipedia.
Plastic pollution has a profound impact on
ocean life (Chapter 1). There are benefits to
ocean life from removing some of this plastic,
however it is necessary to look holistically
at the impact of the cleanup operation on the
environment as well. The solution to the plastic
problem should not be worse than the problem
itself and therefore, in this chapter, an analysis
of the impact of The Ocean Cleanup Array on
the oceanic ecosystem has been included. It
is estimated that although The Ocean Cleanup
Array can have a significant influence on local
ecologic properties, precautions have been
taken to ensure that biomass removal is limited.