INTRODUCTION
Apart from in situ and laboratory methods, the assessment of Posidonia oceanica
meadows also involves data census and satellite imagery. These methods allow for large-scale
monitoring, simple and cost-effective assessment of human-induced pressures on these
ecosystems (Lopez et al., 2009).
In this context, the present study aims to define a straightforward and cost-efficient
method for evaluating the impact of human activities on the Posidonia oceanica meadows at 9
sites along the central Algerian coast. Two complementary approaches are proposed: the first
approach is a visual assessment which uses satellite images, this approach was implemented in
two distinct methods. The second approach is quantitative, utilizing governmental census data
in conjunction with mapping, this approach was implemented in three distinct methods to
quantify the exposure of seagrass habitats to anthropogenic pressures. A total of five methods
were applied. Finally, the robustness of these methods will be verified by studying their
relationship with a ground truth data set represented by an Ecological Quality Ratio (EQR),
previously calculated for the same study sites and based on five parameters of vitality of
Posidonia oceanica meadows. The results of this step will serve to validate the approach that
better reflect the ecological status of these meadows.
Apart from in situ and laboratory methods, the assessment of Posidonia oceanica
meadows also involves data census and satellite imagery. These methods allow for large-scale
monitoring, simple and cost-effective assessment of human-induced pressures on these
ecosystems (Lopez et al., 2009).
In this context, the present study aims to define a straightforward and cost-efficient
method for evaluating the impact of human activities on the Posidonia oceanica meadows at 9
sites along the central Algerian coast. Two complementary approaches are proposed: the first
approach is a visual assessment which uses satellite images, this approach was implemented in
two distinct methods. The second approach is quantitative, utilizing governmental census data
in conjunction with mapping, this approach was implemented in three distinct methods to
quantify the exposure of seagrass habitats to anthropogenic pressures. A total of five methods
were applied. Finally, the robustness of these methods will be verified by studying their
relationship with a ground truth data set represented by an Ecological Quality Ratio (EQR),
previously calculated for the same study sites and based on five parameters of vitality of
Posidonia oceanica meadows. The results of this step will serve to validate the approach that
better reflect the ecological status of these meadows.