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ABSTRACT
In this study, we examined the Posidonia oceanica (L.) Delile herbarium at Stareso, a privileged
reference site due to its protection against pollution. Samples of bundles were taken in front
of the station at a depth of 10 meters and then following a bathymetric profile, parallel
to recordings of environmental parameters. Different parameters and biometric indices were
measured and calculated. Measurements of trace element content were planned in these same leaf
bundles but could not be carried out for technical reasons. Therefore, we analyzed an existing
dataset on trace element content in the rhizomes of Posidonia oceanica (L.) Delile. We examined
the seasonal and multi-year cycle as well as small-scale spatial variations in trace element content
in these rhizomes. To do so, the rhizomes were sampled at six stations in Calvi Bay in June 2010,
as well as at a depth of 10 meters in front of Stareso and on the Plateau des Chèvres, seasonally
in 2008, 2009 and 2010.
Our results show that some elements have an affinity to accumulate in rhizomes, so that trace
element concentrations vary depending on the location of sampling stations and the sampling
period. In addition, the relatively high concentration levels of these elements are mainly due
to anthropogenic activities rather than natural processes, and low or decreasing/stabilizing levels
over time are likely due to the reduction of their anthropogenic use.
Sediment is a primary factor in determining bioaccumulated concentrations in rhizomes,
as it conditions its own enrichment in trace elements and then contamination of the rhizomes
by absorption through the roots. As for the biometric parameters of Posidonia oceanica (L.) Delile
bundles, they follow known seasonal and bathymetric trends, widely discussed in scientific
literature. Finally, this experiment confirms the reliability of using Posidonia oceanica (L.) Delile
as a bio-indicator of chemical contamination in sediments.
Keywords: Trace elements, seasonal and multi-annual cycle, spatial variation, sediment,
Posidonia oceanica (L.) Delile, rhizomes, biometry.
ABSTRACT
In this study, we examined the Posidonia oceanica (L.) Delile herbarium at Stareso, a privileged
reference site due to its protection against pollution. Samples of bundles were taken in front
of the station at a depth of 10 meters and then following a bathymetric profile, parallel
to recordings of environmental parameters. Different parameters and biometric indices were
measured and calculated. Measurements of trace element content were planned in these same leaf
bundles but could not be carried out for technical reasons. Therefore, we analyzed an existing
dataset on trace element content in the rhizomes of Posidonia oceanica (L.) Delile. We examined
the seasonal and multi-year cycle as well as small-scale spatial variations in trace element content
in these rhizomes. To do so, the rhizomes were sampled at six stations in Calvi Bay in June 2010,
as well as at a depth of 10 meters in front of Stareso and on the Plateau des Chèvres, seasonally
in 2008, 2009 and 2010.
Our results show that some elements have an affinity to accumulate in rhizomes, so that trace
element concentrations vary depending on the location of sampling stations and the sampling
period. In addition, the relatively high concentration levels of these elements are mainly due
to anthropogenic activities rather than natural processes, and low or decreasing/stabilizing levels
over time are likely due to the reduction of their anthropogenic use.
Sediment is a primary factor in determining bioaccumulated concentrations in rhizomes,
as it conditions its own enrichment in trace elements and then contamination of the rhizomes
by absorption through the roots. As for the biometric parameters of Posidonia oceanica (L.) Delile
bundles, they follow known seasonal and bathymetric trends, widely discussed in scientific
literature. Finally, this experiment confirms the reliability of using Posidonia oceanica (L.) Delile
as a bio-indicator of chemical contamination in sediments.
Keywords: Trace elements, seasonal and multi-annual cycle, spatial variation, sediment,
Posidonia oceanica (L.) Delile, rhizomes, biometry.