7.3.2.2 Primary Production from Satellite Data
According to Spalding et al. (2007), the Alboran Sea is an ecoregion included in the
Mediterranean province, defined in general as a low productivity ecosystem
(<150 g CÁm
À2
Áyear
À1 ) (Aquarone et al. 2009). However, at smaller regional scales
within the Mediterranean, there is high spatial and temporal variability in PP. Thus,
Bosc et al. (2004), analyzed 4 year mean PP values derived from satellite images for
different Mediterranean Sea regions, and concluded that the Alboran Sea is the most
productive region of the Mediterranean, with an average annual PP of
230 g CÁm
À2
Áyear
À1 , being this value almost 100 g CÁm
À2
Áyear
À1 higher than the
overall mean for the Mediterranean basin. These values are in agreement with the
results obtained by Antoine et al. (1995), who estimated a mean PP of
156 g CÁm
À2
Áyear
À1 for the Mediterranean and 250 g CÁm
À2
Áyear
À1 for the Alboran
Sea. Based on a 3D-biogeochemical model (1999–2004) Lazzari et al. (2012),
estimated for the Alboran Sea a net PP (NPP) of 274 Æ 11 g CÁm
À2
Áyear
À1 and
classified this basin as mesotrophic (integrated NPP between 100 and
300 g CÁm
À2
Áyear
À1 ), showing the NPP a clear seasonal pattern with higher values
between January and June and the highest peaks between February and May (Lazzari
et al. 2012).
Figure 7.7 shows the spatial heterogeneity of PP in the upper 100 m in the
Mediterranean and the Alboran Sea in spring (May), which according to the results
of Lazzari et al. (2012) is one of the most productive months in the Alboran Sea. The
depth-integrated (0–100 m) PP of the whole Mediterranean Sea depicts the Alboran
Sea as the most productive region (Fig. 7.7a). In spite of being the region with the
highest integrated NPP of the Mediterranean Sea, it is noteworthy to mention the
existence of very strong spatial differences within the Alboran Sea, with zones where
PPint values are extremely low and others with extremely high values (Fig. 7.7b).
The areas with the highest PP (0.6 g CÁm
À2
Áday
À1 ) are located in the northern part of
the Alboran Sea (between Malaga and Motril) and the southern part of the eastern
basin (off the eastern Moroccan coasts) (Fig. 7.7b). These values extrapolated to the
whole year would result in a mean PP of 219 g CÁm
À2
Áyear
À1
, which is similar to the
value given by Lazzari et al. (2012). On overall, Fig. 7.7b illustrates the coexistence
in the Alboran Sea of oligotrophic, poor Chl-a, and low productive areas, together
with mesotrophic, rich Chl-a, and high productive areas.
232
T. Ramírez et al.
According to Spalding et al. (2007), the Alboran Sea is an ecoregion included in the
Mediterranean province, defined in general as a low productivity ecosystem
(<150 g CÁm
À2
Áyear
À1 ) (Aquarone et al. 2009). However, at smaller regional scales
within the Mediterranean, there is high spatial and temporal variability in PP. Thus,
Bosc et al. (2004), analyzed 4 year mean PP values derived from satellite images for
different Mediterranean Sea regions, and concluded that the Alboran Sea is the most
productive region of the Mediterranean, with an average annual PP of
230 g CÁm
À2
Áyear
À1 , being this value almost 100 g CÁm
À2
Áyear
À1 higher than the
overall mean for the Mediterranean basin. These values are in agreement with the
results obtained by Antoine et al. (1995), who estimated a mean PP of
156 g CÁm
À2
Áyear
À1 for the Mediterranean and 250 g CÁm
À2
Áyear
À1 for the Alboran
Sea. Based on a 3D-biogeochemical model (1999–2004) Lazzari et al. (2012),
estimated for the Alboran Sea a net PP (NPP) of 274 Æ 11 g CÁm
À2
Áyear
À1 and
classified this basin as mesotrophic (integrated NPP between 100 and
300 g CÁm
À2
Áyear
À1 ), showing the NPP a clear seasonal pattern with higher values
between January and June and the highest peaks between February and May (Lazzari
et al. 2012).
Figure 7.7 shows the spatial heterogeneity of PP in the upper 100 m in the
Mediterranean and the Alboran Sea in spring (May), which according to the results
of Lazzari et al. (2012) is one of the most productive months in the Alboran Sea. The
depth-integrated (0–100 m) PP of the whole Mediterranean Sea depicts the Alboran
Sea as the most productive region (Fig. 7.7a). In spite of being the region with the
highest integrated NPP of the Mediterranean Sea, it is noteworthy to mention the
existence of very strong spatial differences within the Alboran Sea, with zones where
PPint values are extremely low and others with extremely high values (Fig. 7.7b).
The areas with the highest PP (0.6 g CÁm
À2
Áday
À1 ) are located in the northern part of
the Alboran Sea (between Malaga and Motril) and the southern part of the eastern
basin (off the eastern Moroccan coasts) (Fig. 7.7b). These values extrapolated to the
whole year would result in a mean PP of 219 g CÁm
À2
Áyear
À1
, which is similar to the
value given by Lazzari et al. (2012). On overall, Fig. 7.7b illustrates the coexistence
in the Alboran Sea of oligotrophic, poor Chl-a, and low productive areas, together
with mesotrophic, rich Chl-a, and high productive areas.
232
T. Ramírez et al.