2.3 Aquatic Organisms
23
particular interests which are further discussed in other chapters are the frogs whose
skin serves as a source of some bioactive polymers and other aquatic animals with
special features which aid them in surviving in the deepest part of the ocean.
The decline or surge in the population of fish in aquatic environment has long been
used as an indication of the presence or absence of contaminants within such aquatic
environment. In industrial quality checks, the product safety for human consumption
is confirmed by testing on fish in controlled aquatic systems such as aquarium or
ponds (Christophe et al. 2015). The aquatic animals serve as a source of food and
livelihood for various life-forms including humans. There is need to maintain a balance between the population of different aquatic animals in order to ensure constant
supply of aquatic resources.
One of the aquatic invertebrates which recently pose a nuisance to the fisheries
industry is the jellyfish. In recent years, giant jellyfish population explosion in the
ocean has been reported (ref). The cause of this bloom has been attributed to the
decline in the population of the larger aquatic organisms which prey on these jellyfish
due to overfishing, eutrophication of coastal waters, global warming, changes to the
aquatic habitat and translocation (Dong 2019). The jellyfish bloom has resulted in a
decline in the population of smaller finfish as they are poisoned by these jellyfish. This
results in devastating loss to fishermen, aqua tourism industry and also destruction
of cooling systems of power plants located on the coast. Measures taken to address
this include the development of jellyfish bloom detection tools (Azmar et al. 2017),
consuming the jellyfish for food and use as feedstock in biopolymer industry as
reviewed in the subsequent chapter in this book.
2.3.4 Carnivorous Aquatic Plants
Whether on land or in the water, carnivorous plants are very rare. Globally, there are
over 700 species of carnivorous plants from over 5 orders and 10 genera (Lima et al.
2018). Examples of species of aquatic carnivorous plants are Aldrovanda vesiculosa,
Utricularia vulgaris, U. reflexa Oliver, U. stygia Thor and U. intermedia Hayne
(Adamec 2010). Two common aquatic carnivorous plants are the water wheels and
the pitcher plants. The evolution of plants to feed on insects is thought to originate
from the natural defense which plants have against fungi and bacteria (Schulze et al.
2012). Since fungi and insects have the chitin-based structure in common, similar
chitin degrading mechanism is involved in breaking down the chitinous shells of
insects. Carnivory in plants is thought to be an adaptation to the limitation of nutrients
in the growth medium. While to other plants, the roots serve as the main organ for
the uptake of nutrients. In carnivorous plants, the leaves have adapted a feature for
taking up nutrients from the trapped animal (mostly insects and larvae).
Some carnivorous plants adopt passive techniques for attracting prey, while others adopt active techniques for attracting prey (Forterre et al. 2005). The passive
technique involves insect being lured toward a sticky surface where they feed on the
plant nectar; however, by the architecture of the plants they are unable to leave due
23
particular interests which are further discussed in other chapters are the frogs whose
skin serves as a source of some bioactive polymers and other aquatic animals with
special features which aid them in surviving in the deepest part of the ocean.
The decline or surge in the population of fish in aquatic environment has long been
used as an indication of the presence or absence of contaminants within such aquatic
environment. In industrial quality checks, the product safety for human consumption
is confirmed by testing on fish in controlled aquatic systems such as aquarium or
ponds (Christophe et al. 2015). The aquatic animals serve as a source of food and
livelihood for various life-forms including humans. There is need to maintain a balance between the population of different aquatic animals in order to ensure constant
supply of aquatic resources.
One of the aquatic invertebrates which recently pose a nuisance to the fisheries
industry is the jellyfish. In recent years, giant jellyfish population explosion in the
ocean has been reported (ref). The cause of this bloom has been attributed to the
decline in the population of the larger aquatic organisms which prey on these jellyfish
due to overfishing, eutrophication of coastal waters, global warming, changes to the
aquatic habitat and translocation (Dong 2019). The jellyfish bloom has resulted in a
decline in the population of smaller finfish as they are poisoned by these jellyfish. This
results in devastating loss to fishermen, aqua tourism industry and also destruction
of cooling systems of power plants located on the coast. Measures taken to address
this include the development of jellyfish bloom detection tools (Azmar et al. 2017),
consuming the jellyfish for food and use as feedstock in biopolymer industry as
reviewed in the subsequent chapter in this book.
2.3.4 Carnivorous Aquatic Plants
Whether on land or in the water, carnivorous plants are very rare. Globally, there are
over 700 species of carnivorous plants from over 5 orders and 10 genera (Lima et al.
2018). Examples of species of aquatic carnivorous plants are Aldrovanda vesiculosa,
Utricularia vulgaris, U. reflexa Oliver, U. stygia Thor and U. intermedia Hayne
(Adamec 2010). Two common aquatic carnivorous plants are the water wheels and
the pitcher plants. The evolution of plants to feed on insects is thought to originate
from the natural defense which plants have against fungi and bacteria (Schulze et al.
2012). Since fungi and insects have the chitin-based structure in common, similar
chitin degrading mechanism is involved in breaking down the chitinous shells of
insects. Carnivory in plants is thought to be an adaptation to the limitation of nutrients
in the growth medium. While to other plants, the roots serve as the main organ for
the uptake of nutrients. In carnivorous plants, the leaves have adapted a feature for
taking up nutrients from the trapped animal (mostly insects and larvae).
Some carnivorous plants adopt passive techniques for attracting prey, while others adopt active techniques for attracting prey (Forterre et al. 2005). The passive
technique involves insect being lured toward a sticky surface where they feed on the
plant nectar; however, by the architecture of the plants they are unable to leave due