Limits...
The biodiversity of the Mediterranean Sea: estimates, patterns, and threats.

Coll M, Piroddi C, Steenbeek J, Kaschner K, Ben Rais Lasram F, Aguzzi J, Ballesteros E, Bianchi CN, Corbera J, Dailianis T, Danovaro R, Estrada M, Froglia C, Galil BS, Gasol JM, Gertwagen R, Gil J, Guilhaumon F, Kesner-Reyes K, Kitsos MS, Koukouras A, Lampadariou N, Laxamana E, López-Fé de la Cuadra CM, Lotze HK, Martin D, Mouillot D, Oro D, Raicevich S, Rius-Barile J, Saiz-Salinas JI, San Vicente C, Somot S, Templado J, Turon X, Vafidis D, Villanueva R, Voultsiadou E - PLoS ONE (2010)

Bottom Line: Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea.Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth.This abstract has been translated to other languages (File S1).

View Article: PubMed Central - PubMed

Affiliation: Institut de Ciències del Mar, Scientific Spanish Council (ICM-CSIC), Barcelona, Spain. mcoll@icm.csic.es

ABSTRACT
The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet-undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well. This abstract has been translated to other languages (File S1).

Show MeSH

Related in: MedlinePlus

Historical changes and threats of species in the Mediterranean Sea.(A) Historical trends in the proportion of species being depleted (>50% decline), rare (>90% decline), or extirpated (100% decline) in the North Adriatic Sea, based on data for 64 economically and ecologically important species for which long-term records are available. Temporal trends for alien species refer to recorded exotic mollusks in the whole Mediterranean Sea [272]. (B) Shifts in species diversity of the North Adriatic Sea over historical time scales. Species depletions and extirpations occurred mostly in larger species groups, while invasions occurred in smaller and lower trophic-level species [data from 271]. (C) Threats to diversity in the North Adriatic Sea over historical time scales. Shown is the percent of recorded species depletions and extinctions caused by, or attributed to, different human impacts. Also shown is whether human impacts acted as single or multiple causes. Data were adapted from Lotze et al. [113].
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2914016&req=5

pone-0011842-g008: Historical changes and threats of species in the Mediterranean Sea.(A) Historical trends in the proportion of species being depleted (>50% decline), rare (>90% decline), or extirpated (100% decline) in the North Adriatic Sea, based on data for 64 economically and ecologically important species for which long-term records are available. Temporal trends for alien species refer to recorded exotic mollusks in the whole Mediterranean Sea [272]. (B) Shifts in species diversity of the North Adriatic Sea over historical time scales. Species depletions and extirpations occurred mostly in larger species groups, while invasions occurred in smaller and lower trophic-level species [data from 271]. (C) Threats to diversity in the North Adriatic Sea over historical time scales. Shown is the percent of recorded species depletions and extinctions caused by, or attributed to, different human impacts. Also shown is whether human impacts acted as single or multiple causes. Data were adapted from Lotze et al. [113].

Mentions: The pattern of a generally decreasing diversity with increasing depth was also documented here for invertebrate and fish species (Figures 3, 4, 7, and 8) and is consistent with previous studies [e.g., [31],[228]]. Diversity was concentrated in coastal areas and continental shelves, mainly above 200 m depth. However, patterns did not necessarily show a monotonic decrease with depth. For example, more polychaete species inhabited shallow waters than deep waters, particularly below 1,000 m deep, but this pattern was less clear when looking at maximum ranges of depth (Figure 7a, File S2). It is not clear whether this is a real pattern of lower deep-sea diversity or a result of the lack of proper faunistic studies in the Mediterranean at those depths. Larger numbers of cumacean species were found in shallow waters of 0–99 m depth (48 species) and between 200 m and 1,400 m depth, but species richness decreased below this depth (Figure 7b, references in File S2). The highest endemism (43.8%) was found between 0 and 99 m depth. The largest number of mysidaceans (54 species) was also found in shallow waters less than100 m deep. At depths between 100 m and 1,000 m, 27 species were found, and below 1,000 m, 21 species. The level of endemism was also higher in the 0–100 m depth interval (29 species, 78.4% of total endemism) than in the 100–1,000 m interval (3 species, 8.1%) or below 1,000 m (5 species, 13.5%), in line with results obtained for cumaceans. The circalittoral zone was the region with highest anthozoan species richness (61.8% by numbers of species) followed by the infralittoral (57.6%) and bathyal (40%) zones (File S2). Half of the total number of species were restricted to one of the infra-, circa-, or bathyal zones, and 9.7% were eurybathic, while the remaining species (40%) were intermediate in depth distribution. We also found exceptions to the pattern of decreasing diversity with depth. The bathymetric range of Mediterranean sipunculans was generally quite wide [229]. Most of the Mediterranean records were bathyal, whereas there were few sublittoral records (File S2).


The biodiversity of the Mediterranean Sea: estimates, patterns, and threats.

Coll M, Piroddi C, Steenbeek J, Kaschner K, Ben Rais Lasram F, Aguzzi J, Ballesteros E, Bianchi CN, Corbera J, Dailianis T, Danovaro R, Estrada M, Froglia C, Galil BS, Gasol JM, Gertwagen R, Gil J, Guilhaumon F, Kesner-Reyes K, Kitsos MS, Koukouras A, Lampadariou N, Laxamana E, López-Fé de la Cuadra CM, Lotze HK, Martin D, Mouillot D, Oro D, Raicevich S, Rius-Barile J, Saiz-Salinas JI, San Vicente C, Somot S, Templado J, Turon X, Vafidis D, Villanueva R, Voultsiadou E - PLoS ONE (2010)

Historical changes and threats of species in the Mediterranean Sea.(A) Historical trends in the proportion of species being depleted (>50% decline), rare (>90% decline), or extirpated (100% decline) in the North Adriatic Sea, based on data for 64 economically and ecologically important species for which long-term records are available. Temporal trends for alien species refer to recorded exotic mollusks in the whole Mediterranean Sea [272]. (B) Shifts in species diversity of the North Adriatic Sea over historical time scales. Species depletions and extirpations occurred mostly in larger species groups, while invasions occurred in smaller and lower trophic-level species [data from 271]. (C) Threats to diversity in the North Adriatic Sea over historical time scales. Shown is the percent of recorded species depletions and extinctions caused by, or attributed to, different human impacts. Also shown is whether human impacts acted as single or multiple causes. Data were adapted from Lotze et al. [113].
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2914016&req=5

pone-0011842-g008: Historical changes and threats of species in the Mediterranean Sea.(A) Historical trends in the proportion of species being depleted (>50% decline), rare (>90% decline), or extirpated (100% decline) in the North Adriatic Sea, based on data for 64 economically and ecologically important species for which long-term records are available. Temporal trends for alien species refer to recorded exotic mollusks in the whole Mediterranean Sea [272]. (B) Shifts in species diversity of the North Adriatic Sea over historical time scales. Species depletions and extirpations occurred mostly in larger species groups, while invasions occurred in smaller and lower trophic-level species [data from 271]. (C) Threats to diversity in the North Adriatic Sea over historical time scales. Shown is the percent of recorded species depletions and extinctions caused by, or attributed to, different human impacts. Also shown is whether human impacts acted as single or multiple causes. Data were adapted from Lotze et al. [113].
Mentions: The pattern of a generally decreasing diversity with increasing depth was also documented here for invertebrate and fish species (Figures 3, 4, 7, and 8) and is consistent with previous studies [e.g., [31],[228]]. Diversity was concentrated in coastal areas and continental shelves, mainly above 200 m depth. However, patterns did not necessarily show a monotonic decrease with depth. For example, more polychaete species inhabited shallow waters than deep waters, particularly below 1,000 m deep, but this pattern was less clear when looking at maximum ranges of depth (Figure 7a, File S2). It is not clear whether this is a real pattern of lower deep-sea diversity or a result of the lack of proper faunistic studies in the Mediterranean at those depths. Larger numbers of cumacean species were found in shallow waters of 0–99 m depth (48 species) and between 200 m and 1,400 m depth, but species richness decreased below this depth (Figure 7b, references in File S2). The highest endemism (43.8%) was found between 0 and 99 m depth. The largest number of mysidaceans (54 species) was also found in shallow waters less than100 m deep. At depths between 100 m and 1,000 m, 27 species were found, and below 1,000 m, 21 species. The level of endemism was also higher in the 0–100 m depth interval (29 species, 78.4% of total endemism) than in the 100–1,000 m interval (3 species, 8.1%) or below 1,000 m (5 species, 13.5%), in line with results obtained for cumaceans. The circalittoral zone was the region with highest anthozoan species richness (61.8% by numbers of species) followed by the infralittoral (57.6%) and bathyal (40%) zones (File S2). Half of the total number of species were restricted to one of the infra-, circa-, or bathyal zones, and 9.7% were eurybathic, while the remaining species (40%) were intermediate in depth distribution. We also found exceptions to the pattern of decreasing diversity with depth. The bathymetric range of Mediterranean sipunculans was generally quite wide [229]. Most of the Mediterranean records were bathyal, whereas there were few sublittoral records (File S2).

Bottom Line: Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea.Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth.This abstract has been translated to other languages (File S1).

View Article: PubMed Central - PubMed

Affiliation: Institut de Ciències del Mar, Scientific Spanish Council (ICM-CSIC), Barcelona, Spain. mcoll@icm.csic.es

ABSTRACT
The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet-undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well. This abstract has been translated to other languages (File S1).

Show MeSH
Related in: MedlinePlus