LITERATURE REVIEW
1.3. Economic and ecological roles of Posidonia oceanica meadows
Posidonia oceanica meadows play an essential role in marine ecosystems, both
ecologically and economically. These essential marine habitats are home to a diversity of
animal species ,they serve as both feeding grounds and breeding grounds (spawning and nursery
areas), ( Templado, 1984; Boudouresque et al., 2006;).
Posidonia oceanica meadows generate significant primary production, comparable to that
of tropical forests (Pergent-Martini et al., 2006). This abundance of plant matter is consumed
within the meadow, but a substantial proportion (30 to 35%) is exported to other ecosystems,
where it serves as the foundation of numerous food webs (Rico-Raimondino, 1995). The
meadows are essential for the production of oxygen and organic matter. The associated leaves
and epiphytic algae make a major contribution to this production, making them an important
factor in the oxygenation of water and sediments in the infralittoral zone (Boudouresque et al.,
2006). They also contribute to 12% of the carbon stored in ocean sediments and play a crucial
role in regulating the global carbon cycle, (Marbà et al., 2014) estimates, Posidonia oceanica
meadows in the Mediterranean basin sequester approximately 20 to 27Tg of CO2 annually.
Consequently, these meadows serve as natural carbon sinks, contributing to the mitigation of
climate change (Pergent et al., 2014). If the ongoing decline of Posidonia oceanica meadows
is not halted, their crucial role could be significantly undermined (Marbà et al., 2014).
Posidonia oceanica meadows serve as a barrier against hydrodynamics, contributing for the
retention of suspended particles. and enhancing water clarity. They also provide coastal defense
against erosion (Jeudy de Grissac and Boudouresque, 1985; Terrados and Duarte, 2000).
Underground matte serves to stabilize soft bottoms by functioning as a sediment trap (Molinier
and Picard, 1952).
Taking into account all these details, Posidonia oceanica meadows have a significant
economic value, with prices ranging from €1,965 to €2,960 per ton. Nevertheless, their
deterioration can result in significant economic losses (an estimation of €58,854,676 based on
the quantities harvested from 1990 to 2014 in Gabes Gulf (SE Tunisia) (El Zrelli et al., 2020).
In addition, Posidonia oceanica serves as a 'Biological Quality Element' in different
monitoring programs as those mandated by the EU Water Framework Directive, offering
insights into the status of coastal ecosystems (Rigo et al., 2021).
1.3. Economic and ecological roles of Posidonia oceanica meadows
Posidonia oceanica meadows play an essential role in marine ecosystems, both
ecologically and economically. These essential marine habitats are home to a diversity of
animal species ,they serve as both feeding grounds and breeding grounds (spawning and nursery
areas), ( Templado, 1984; Boudouresque et al., 2006;).
Posidonia oceanica meadows generate significant primary production, comparable to that
of tropical forests (Pergent-Martini et al., 2006). This abundance of plant matter is consumed
within the meadow, but a substantial proportion (30 to 35%) is exported to other ecosystems,
where it serves as the foundation of numerous food webs (Rico-Raimondino, 1995). The
meadows are essential for the production of oxygen and organic matter. The associated leaves
and epiphytic algae make a major contribution to this production, making them an important
factor in the oxygenation of water and sediments in the infralittoral zone (Boudouresque et al.,
2006). They also contribute to 12% of the carbon stored in ocean sediments and play a crucial
role in regulating the global carbon cycle, (Marbà et al., 2014) estimates, Posidonia oceanica
meadows in the Mediterranean basin sequester approximately 20 to 27Tg of CO2 annually.
Consequently, these meadows serve as natural carbon sinks, contributing to the mitigation of
climate change (Pergent et al., 2014). If the ongoing decline of Posidonia oceanica meadows
is not halted, their crucial role could be significantly undermined (Marbà et al., 2014).
Posidonia oceanica meadows serve as a barrier against hydrodynamics, contributing for the
retention of suspended particles. and enhancing water clarity. They also provide coastal defense
against erosion (Jeudy de Grissac and Boudouresque, 1985; Terrados and Duarte, 2000).
Underground matte serves to stabilize soft bottoms by functioning as a sediment trap (Molinier
and Picard, 1952).
Taking into account all these details, Posidonia oceanica meadows have a significant
economic value, with prices ranging from €1,965 to €2,960 per ton. Nevertheless, their
deterioration can result in significant economic losses (an estimation of €58,854,676 based on
the quantities harvested from 1990 to 2014 in Gabes Gulf (SE Tunisia) (El Zrelli et al., 2020).
In addition, Posidonia oceanica serves as a 'Biological Quality Element' in different
monitoring programs as those mandated by the EU Water Framework Directive, offering
insights into the status of coastal ecosystems (Rigo et al., 2021).