278
H. Dutta
(Elvira and Almodóvar 2001). Thus, it is evident that species invasion is a complex process that involves several different determinants that influence its expansion.
Accordingly, different initiatives might be needed for management. Human activity is an important determinant that spreads alien species in multiple ways. Under
several situations, human activity cannot be prevented. However, proper awareness
would definitely encourage the public to carry out such activity in ways that do not
accelerate negative effects on the aquatic environment.
From the literature survey, it can be summarized that climate change aids in the
propagation of invasive species by facilitating their introduction, modifying habitats
and increasing their vulnerability to invasion and favouring the growth and dominance of the invading species. These effects are not confined to any specific aquatic
ecosystem or organism. The present review highlighted some important species that
derive benefits from climate change. However, there are several other examples that
can be cited from both fresh and marine waters. The review also brought to light the
synergistic effects of climate change on eutrophication, which in turn can also intensify species invasion. This precisely demonstrates a situation in which the negative
impact of one issue is magnified by another. In fact, there is a vicious cycle among
the problems in which a positive feedback exists among anthropogenic impacts and
the three problems.
Climate change results in greater water temperatures, decreased ice cover duration,
alterations in the patterns of stream flow, greater salinization, and increased demand
for water storage and conveyance structures. Consequently, fish culture facilities and
water gardens are expanded to new areas. As a whole, such changes modify the
pathways through which non native species enter aquatic systems (Rahel and Olden
2008). Changes triggered by global warming affect current patterns in oceans and in
this way local dispersal mechanisms are altered. In addition, competitive interactions
between non native and native species are changed due to the onset of new thermal
optima and/or different carbonate chemistry (Occhipinti-Ambrogi 2007). Besides,
several species are also shifting their distribution ranges towards higher latitudes due
to climate change (CIESM 2008). The Mediterranean coastal areas could suffer from
such impacts because their temperatures are expected to increase by at least 1–2.5 °C
by the end of the 21st century (Di Carlo and Otero 2012). In order to mitigate the
effects of climate change the establishment of marine protected areas and no-take
reserves has been suggested because climatic disturbances are likely to cause lower
negative impacts on populations and intact communities (Harley et al. 2006).
Algal blooms are natural phenomena (Anderson et al. 2002). The occurrence
of such blooms has increased in marine and freshwater ecosystems due to physical,
chemical and biological factors including climate changes and anthropogenic impacts
(Sanseverino et al. 2016). In fact, climate change has been intensifying the symptoms of eutrophication in freshwaters (Jeppesen et al. 2010) and it is projected that
global warming would increase cyanobacterial blooms in lakes (Wagner and Adrian
2009). As a whole, eutrophication and global warming enhance their proliferation
and expansion (O’Neil et al. 2012). Vice versa, eutrophication is likely to promote
climate change (Moss et al. 2011). This exemplifies the situation when a natural event
becomes harmful after crossing a particular threshold under the influence of climate
H. Dutta
(Elvira and Almodóvar 2001). Thus, it is evident that species invasion is a complex process that involves several different determinants that influence its expansion.
Accordingly, different initiatives might be needed for management. Human activity is an important determinant that spreads alien species in multiple ways. Under
several situations, human activity cannot be prevented. However, proper awareness
would definitely encourage the public to carry out such activity in ways that do not
accelerate negative effects on the aquatic environment.
From the literature survey, it can be summarized that climate change aids in the
propagation of invasive species by facilitating their introduction, modifying habitats
and increasing their vulnerability to invasion and favouring the growth and dominance of the invading species. These effects are not confined to any specific aquatic
ecosystem or organism. The present review highlighted some important species that
derive benefits from climate change. However, there are several other examples that
can be cited from both fresh and marine waters. The review also brought to light the
synergistic effects of climate change on eutrophication, which in turn can also intensify species invasion. This precisely demonstrates a situation in which the negative
impact of one issue is magnified by another. In fact, there is a vicious cycle among
the problems in which a positive feedback exists among anthropogenic impacts and
the three problems.
Climate change results in greater water temperatures, decreased ice cover duration,
alterations in the patterns of stream flow, greater salinization, and increased demand
for water storage and conveyance structures. Consequently, fish culture facilities and
water gardens are expanded to new areas. As a whole, such changes modify the
pathways through which non native species enter aquatic systems (Rahel and Olden
2008). Changes triggered by global warming affect current patterns in oceans and in
this way local dispersal mechanisms are altered. In addition, competitive interactions
between non native and native species are changed due to the onset of new thermal
optima and/or different carbonate chemistry (Occhipinti-Ambrogi 2007). Besides,
several species are also shifting their distribution ranges towards higher latitudes due
to climate change (CIESM 2008). The Mediterranean coastal areas could suffer from
such impacts because their temperatures are expected to increase by at least 1–2.5 °C
by the end of the 21st century (Di Carlo and Otero 2012). In order to mitigate the
effects of climate change the establishment of marine protected areas and no-take
reserves has been suggested because climatic disturbances are likely to cause lower
negative impacts on populations and intact communities (Harley et al. 2006).
Algal blooms are natural phenomena (Anderson et al. 2002). The occurrence
of such blooms has increased in marine and freshwater ecosystems due to physical,
chemical and biological factors including climate changes and anthropogenic impacts
(Sanseverino et al. 2016). In fact, climate change has been intensifying the symptoms of eutrophication in freshwaters (Jeppesen et al. 2010) and it is projected that
global warming would increase cyanobacterial blooms in lakes (Wagner and Adrian
2009). As a whole, eutrophication and global warming enhance their proliferation
and expansion (O’Neil et al. 2012). Vice versa, eutrophication is likely to promote
climate change (Moss et al. 2011). This exemplifies the situation when a natural event
becomes harmful after crossing a particular threshold under the influence of climate