Exploring Synergistic Inter Linkages Among Three Ecological …
267
3 Results
3.1 Species Invasion in the Aquatic Environment
3.1.1 Invasion as a Problem
Invasive species are often functionally different from the components of the recipient
community and give rise to ecological impacts that propagate through the food web
(Gallardo et al. 2016). Aquatic ecosystems are at a great risk to the introductions
of such species, which trigger major disruption in their functioning (An -
delkovi´ c
et al. 2016). Aquatic habitats often consist of interconnected waterways in which
vectors easily enable artificial transport of species and their propagules. Thus, the
characteristics that commonly facilitate biological invasions in terrestrial habitats are
not necessary in aquatic environments. Therefore, features that enhance consumption
and growth substantially increase the probability of establishing and spreading when
a particular species enters a new ecosystem (McKnight et al. 2017).
The negative impacts of invasive species include habitat damage, community
change, incidence agricultural and aquaculture pests, loss of biodiversity and genetic
pollution/extinction. Such species also threaten marine industries like fishing and
tourism as well as human health and marine infrastructure (Bax et al. 2003; Chen
et al. 2017). Exotic species not only lead to biodiversity loss by elevating extinction
levels, but also by depressing speciation in ecosystems (Stigall 2011).
Economic globalization has accelerated the expansion of exotic species and their
impacts of ecosystems have become global issues (Gurevitch and Padilla 2004).
Anthropogenic activities such as aquaculture, biocontrol, shipping, stocking, canals
and aquarium trade play a crucial role in spreading aquatic invasive species (Molnar
et al. 2008; Xiong et al. 2018). Recreational boating is also a major vector that
facilitates primary introduction and secondary spread of marine alien species (Murray
et al. 2011). The role of human activities in this context is evident from the fact that
human vessels, aquaculture, wild fisheries and live food trade serve as important
pathways for the introduction of alien species in the Arctic (Chan et al. 2019). Another
relevant instance is The Suez Canal, which has played an important role in the
introduction of invasive species (e.g. Lessepsian fish species) to the Mediterranean
(Otero et al. 2013).
3.1.2 Freshwater Invasion
Alien plant invasion is a formidable threat in this context, but its impacts have been
studied less in freshwater ecosystems compared with terrestrial habitats (Stiers et al.
2011). However, freshwater ecosystems are more vulnerable to invasions by alien
species than terrestrial ecosystems (Sala et al. 2000; Coetzee et al. 2009). In such
ecosystems, invasive plants lead to the losses of species diversity and contribute to
water quality deterioration (Wang et al. 2016). In fact, invasive aquatic plants have
267
3 Results
3.1 Species Invasion in the Aquatic Environment
3.1.1 Invasion as a Problem
Invasive species are often functionally different from the components of the recipient
community and give rise to ecological impacts that propagate through the food web
(Gallardo et al. 2016). Aquatic ecosystems are at a great risk to the introductions
of such species, which trigger major disruption in their functioning (An -
delkovi´ c
et al. 2016). Aquatic habitats often consist of interconnected waterways in which
vectors easily enable artificial transport of species and their propagules. Thus, the
characteristics that commonly facilitate biological invasions in terrestrial habitats are
not necessary in aquatic environments. Therefore, features that enhance consumption
and growth substantially increase the probability of establishing and spreading when
a particular species enters a new ecosystem (McKnight et al. 2017).
The negative impacts of invasive species include habitat damage, community
change, incidence agricultural and aquaculture pests, loss of biodiversity and genetic
pollution/extinction. Such species also threaten marine industries like fishing and
tourism as well as human health and marine infrastructure (Bax et al. 2003; Chen
et al. 2017). Exotic species not only lead to biodiversity loss by elevating extinction
levels, but also by depressing speciation in ecosystems (Stigall 2011).
Economic globalization has accelerated the expansion of exotic species and their
impacts of ecosystems have become global issues (Gurevitch and Padilla 2004).
Anthropogenic activities such as aquaculture, biocontrol, shipping, stocking, canals
and aquarium trade play a crucial role in spreading aquatic invasive species (Molnar
et al. 2008; Xiong et al. 2018). Recreational boating is also a major vector that
facilitates primary introduction and secondary spread of marine alien species (Murray
et al. 2011). The role of human activities in this context is evident from the fact that
human vessels, aquaculture, wild fisheries and live food trade serve as important
pathways for the introduction of alien species in the Arctic (Chan et al. 2019). Another
relevant instance is The Suez Canal, which has played an important role in the
introduction of invasive species (e.g. Lessepsian fish species) to the Mediterranean
(Otero et al. 2013).
3.1.2 Freshwater Invasion
Alien plant invasion is a formidable threat in this context, but its impacts have been
studied less in freshwater ecosystems compared with terrestrial habitats (Stiers et al.
2011). However, freshwater ecosystems are more vulnerable to invasions by alien
species than terrestrial ecosystems (Sala et al. 2000; Coetzee et al. 2009). In such
ecosystems, invasive plants lead to the losses of species diversity and contribute to
water quality deterioration (Wang et al. 2016). In fact, invasive aquatic plants have