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B. Yan et al.
3.1 Impacts on Marine Phytoplankton and Zooplankton
Phytoplankton are the main producers in the ocean, whose primary productivity
accounts for about 80% of the planet’s total oxygen production. The change of
phytoplankton is closely related to the marine geochemical cycle, among which
microalgae are the most widespread ones. Microalgae belong to autotrophic phytoplankton which is ubiquitous in the marine ecosystem, rich in nutrients, and highly
photosynthetic. Microalgae are the basic components of aquatic food webs and the
most essential plants in aquatic ecosystems [68]. A number of studies had confirmed
the fact that microplastics do interact with microalgae, and this affects their fates.
According to the existing studies, the influence of microalgae on microplastics
is mainly divided into two aspects, one is the change in the properties of plastic
polymers/or biodegradation; the other is the change in polymer density and sinking
behavior (Nava and Leoni). Some studies had also suggested that the biological adhesion process of microplastics may affect its properties, with its adsorption capacity
seems to be accelerated [69, 70]. One study showed that phytoplankton attached to PE
microplastics led to changes in the physicochemical properties of the microplastics,
and ultimately gave rise to changes in the adsorption performance of the microplastics on copper and Tetracycline. When the growth of phytoplankton is restricted, a
variety of algae can secrete viscous substances to polymerize with microplastics and
form algal clusters [71], which can not only change the density and distribution of
microplastics in the ocean, but also promote the low-density plastic particles to sink
into the sediment.
Similarly, microplastics can pose harmful effects on phytoplankton. Microplastics
may have toxic effects on marine phytoplankton due to their hydrophobic property
which can serve as carriers of organic pollutants and heavy metals [72]. Microalgae
are essential primary producers of the aquatic ecosystems [73] and the toxicity of
microplastics exposed to them may affect the entire marine food web.
There are many kinds of microplastics entering the ocean. Low microplastic
concentration has little influence on the growth of phytoplankton, especially algae. So
its impacts are almost negligible [74]. However, a high concentration of microplastics
would pose serious adverse effects on the growth and development of phytoplankton.
It has been reported that under the circumstance of high polystyrene concentration, the production of reactive oxygen species (ROS) in chlorella cells would be
accelerated, thus increasing the degree of cell apoptosis and adversely affecting the
production of chlorella [75].
In addition to various polymer types and additives within different doses of
microplastics, other characteristics such as the size of microplastics may also be
critical to marine phytoplankton. A growing number of studies has shown a link
between the particle size of microplastics and toxicity, and it is generally considered
that the toxicity of microplastics to microalgae increases as the size of microplastics decreases [76]. Tiny particles may inhibit the growth of microalgae more easily
by attaching to the surface of algal cells. For example, inducing shading, blocking
algal pores or gas exchange, and embedding in microalgal cells [77]. The ingestion,
B. Yan et al.
3.1 Impacts on Marine Phytoplankton and Zooplankton
Phytoplankton are the main producers in the ocean, whose primary productivity
accounts for about 80% of the planet’s total oxygen production. The change of
phytoplankton is closely related to the marine geochemical cycle, among which
microalgae are the most widespread ones. Microalgae belong to autotrophic phytoplankton which is ubiquitous in the marine ecosystem, rich in nutrients, and highly
photosynthetic. Microalgae are the basic components of aquatic food webs and the
most essential plants in aquatic ecosystems [68]. A number of studies had confirmed
the fact that microplastics do interact with microalgae, and this affects their fates.
According to the existing studies, the influence of microalgae on microplastics
is mainly divided into two aspects, one is the change in the properties of plastic
polymers/or biodegradation; the other is the change in polymer density and sinking
behavior (Nava and Leoni). Some studies had also suggested that the biological adhesion process of microplastics may affect its properties, with its adsorption capacity
seems to be accelerated [69, 70]. One study showed that phytoplankton attached to PE
microplastics led to changes in the physicochemical properties of the microplastics,
and ultimately gave rise to changes in the adsorption performance of the microplastics on copper and Tetracycline. When the growth of phytoplankton is restricted, a
variety of algae can secrete viscous substances to polymerize with microplastics and
form algal clusters [71], which can not only change the density and distribution of
microplastics in the ocean, but also promote the low-density plastic particles to sink
into the sediment.
Similarly, microplastics can pose harmful effects on phytoplankton. Microplastics
may have toxic effects on marine phytoplankton due to their hydrophobic property
which can serve as carriers of organic pollutants and heavy metals [72]. Microalgae
are essential primary producers of the aquatic ecosystems [73] and the toxicity of
microplastics exposed to them may affect the entire marine food web.
There are many kinds of microplastics entering the ocean. Low microplastic
concentration has little influence on the growth of phytoplankton, especially algae. So
its impacts are almost negligible [74]. However, a high concentration of microplastics
would pose serious adverse effects on the growth and development of phytoplankton.
It has been reported that under the circumstance of high polystyrene concentration, the production of reactive oxygen species (ROS) in chlorella cells would be
accelerated, thus increasing the degree of cell apoptosis and adversely affecting the
production of chlorella [75].
In addition to various polymer types and additives within different doses of
microplastics, other characteristics such as the size of microplastics may also be
critical to marine phytoplankton. A growing number of studies has shown a link
between the particle size of microplastics and toxicity, and it is generally considered
that the toxicity of microplastics to microalgae increases as the size of microplastics decreases [76]. Tiny particles may inhibit the growth of microalgae more easily
by attaching to the surface of algal cells. For example, inducing shading, blocking
algal pores or gas exchange, and embedding in microalgal cells [77]. The ingestion,