Jasna Možina - Academia.edu (original) (raw)

Papers by Jasna Možina

Research paper thumbnail of Global distribution of pteropods representing carbonate functional type biomass

Earth System Science Data Discussions, 2012

Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns... more Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns remain poorly resolved. The aim of this study was to collect and synthesize existing pteropod (Gymnosomata, Thecosomata and Pseudothecosomata) abundance and biomass data, in order to evaluate the global distribution of pteropod carbon biomass, with a particular emphasis on its seasonal, temporal and vertical patterns. We collected 25 902 data points from several online databases and a number of scientific articles. The biomass data has been gridded onto a 360 × 180 • grid, with a vertical resolution of 33 WOA depth levels. Data has been converted to NetCDF format which can be downloaded from PANGAEA, http://doi.pangaea.de/10.1594/PANGAEA.777387. Data were collected between 1951-2010, with sampling depths ranging from 0-1000 m. Pteropod biomass data was either extracted directly or derived through converting abundance to biomass with pteropod specific length to weight conversions. In the Northern Hemisphere (NH) the data were distributed evenly throughout the year, whereas sampling in the Southern Hemisphere was biased towards the austral summer months. 86 % of all biomass values were located in the NH, most (42 %) within the latitudinal band of 30-50 • N. The range of global biomass values spanned over three orders of magnitude, with a mean and median biomass concentration of 8.2 mg C l −1 (SD = 61.4) and 0.25 mg C l −1 , respectively for all data points, and with a mean of 9.1 mg C l −1 (SD = 64.8) and a median of 0.25 mg C l −1 for non-zero biomass values. The highest mean and median biomass concentrations were located in the NH between 40-50 • S (mean biomass: 68.8 mg C l −1 (SD × 213.4) median biomass: 2.5 mg C l −1) while, in the SH, they were within the 70-80 • S latitudinal band (mean: 10.5 mg C l −1 (SD × 38.8) and median: 0.2 mg C l −1). Biomass values were lowest in the equatorial regions. A broad range of biomass concentrations was observed at all depths, with the biomass peak located in the surface layer (0-25 m) and values generally decreasing with depth. However, biomass peaks were located at different depths in different ocean basins: 0-25 m depth in the N Atlantic, 50-100 m in the Pacific, 100-200 m in the Arctic,

Research paper thumbnail of Pteropods on the edge: Cumulative effects of ocean acidification, warming, and deoxygenation

Progress in Oceanography, 2016

Abstract We review the state of knowledge of the individual and community responses of euthecosom... more Abstract We review the state of knowledge of the individual and community responses of euthecosome (shelled) pteropods in the context of global environmental change. In particular, we focus on their responses to ocean acidification, in combination with ocean warming and ocean deoxygenation, as inferred from a growing body of empirical literature, and their relatively nascent place in ecosystem-scale models. Our objectives are: (1) to summarize the threats that these stressors pose to pteropod populations; (2) to demonstrate that pteropods are strong candidate indicators for cumulative effects of OA, warming, and deoxygenation in marine ecosystems; and (3) to provide insight on incorporating pteropods into population and ecosystem models, which will help inform ecosystem-based management of marine resources under future environmental regimes.

Research paper thumbnail of The global distribution of pteropods and their contribution to carbonate and carbon biomass in the modern ocean

Earth System Science Data, 2012

Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns... more Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns remain poorly described. The aim of this study was to collect and synthesise existing pteropod (Gymnosomata, Thecosomata and Pseudothecosomata) abundance and biomass data, in order to evaluate the global distribution of pteropod carbon biomass, with a particular emphasis on temporal and spatial patterns. We collected 25 939 data points from several online databases and 41 scientific articles. These data points corresponded to observations from 15 134 stations, where 93 % of observations were of shelled pteropods (Thecosomata) and 7 % of non-shelled pteropods (Gymnosomata). The biomass data has been gridded onto a 360 × 180 • grid, with a vertical resolution of 33 depth levels. Both the raw data file and the gridded data in NetCDF format can be downloaded from PANGAEA, doi:10.1594/PANGAEA.777387. Data were collected between 1950-2010, with sampling depths ranging from 0-2000 m. Pteropod biomass data was either extracted directly or derived through converting abundance to biomass with pteropod-specific length to carbon biomass conversion algorithms. In the Northern Hemisphere (NH), the data were distributed quite evenly throughout the year, whereas sampling in the Southern Hemisphere (SH) was biased towards winter and summer values. 86 % of all biomass values were located in the NH, most (37 %) within the latitudinal band of 30-60 • N. The range of global biomass values spanned over four orders of magnitude, with mean and median (non-zero) biomass values of 4.6 mg C m −3 (SD = 62.5) and 0.015 mg C m −3 , respectively. The highest mean biomass was located in the SH within the 70-80 • S latitudinal band (39.71 mg C m −3 , SD = 93.00), while the highest median biomass was in the NH, between 40-50 • S (0.06 mg C m −3 , SD = 79.94). Shelled pteropods constituted a mean global carbonate biomass of 23.17 mg CaCO 3 m −3 (based on non-zero records). Total biomass values were lowest in the equatorial regions and equally high at both poles. Pteropods were found at least to depths of 1000 m, with the highest biomass values located in the surface layer (0-10 m) and gradually decreasing with depth, with values in excess of 100 mg C m −3 only found above 200 m depth. Tropical species tended to concentrate at greater depths than temperate or high-latitude species. Global biomass levels in the NH were relatively invariant over the seasonal cycle, but more seasonally variable in the SH. The collected database provides a valuable tool for modellers for the study of marine ecosystem processes and global biogeochemical cycles. By extrapolating regional biomass to a global scale, we established global pteropod biomass to add up to 500 Tg C.

Research paper thumbnail of Global distribution of pteropods representing carbonate functional type biomass

Earth System Science Data Discussions, 2012

Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns... more Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns remain poorly resolved. The aim of this study was to collect and synthesize existing pteropod (Gymnosomata, Thecosomata and Pseudothecosomata) abundance and biomass data, in order to evaluate the global distribution of pteropod carbon biomass, with a particular emphasis on its seasonal, temporal and vertical patterns. We collected 25 902 data points from several online databases and a number of scientific articles. The biomass data has been gridded onto a 360 × 180 • grid, with a vertical resolution of 33 WOA depth levels. Data has been converted to NetCDF format which can be downloaded from PANGAEA, http://doi.pangaea.de/10.1594/PANGAEA.777387. Data were collected between 1951-2010, with sampling depths ranging from 0-1000 m. Pteropod biomass data was either extracted directly or derived through converting abundance to biomass with pteropod specific length to weight conversions. In the Northern Hemisphere (NH) the data were distributed evenly throughout the year, whereas sampling in the Southern Hemisphere was biased towards the austral summer months. 86 % of all biomass values were located in the NH, most (42 %) within the latitudinal band of 30-50 • N. The range of global biomass values spanned over three orders of magnitude, with a mean and median biomass concentration of 8.2 mg C l −1 (SD = 61.4) and 0.25 mg C l −1 , respectively for all data points, and with a mean of 9.1 mg C l −1 (SD = 64.8) and a median of 0.25 mg C l −1 for non-zero biomass values. The highest mean and median biomass concentrations were located in the NH between 40-50 • S (mean biomass: 68.8 mg C l −1 (SD × 213.4) median biomass: 2.5 mg C l −1) while, in the SH, they were within the 70-80 • S latitudinal band (mean: 10.5 mg C l −1 (SD × 38.8) and median: 0.2 mg C l −1). Biomass values were lowest in the equatorial regions. A broad range of biomass concentrations was observed at all depths, with the biomass peak located in the surface layer (0-25 m) and values generally decreasing with depth. However, biomass peaks were located at different depths in different ocean basins: 0-25 m depth in the N Atlantic, 50-100 m in the Pacific, 100-200 m in the Arctic,

Research paper thumbnail of Pteropods on the edge: Cumulative effects of ocean acidification, warming, and deoxygenation

Progress in Oceanography, 2016

Abstract We review the state of knowledge of the individual and community responses of euthecosom... more Abstract We review the state of knowledge of the individual and community responses of euthecosome (shelled) pteropods in the context of global environmental change. In particular, we focus on their responses to ocean acidification, in combination with ocean warming and ocean deoxygenation, as inferred from a growing body of empirical literature, and their relatively nascent place in ecosystem-scale models. Our objectives are: (1) to summarize the threats that these stressors pose to pteropod populations; (2) to demonstrate that pteropods are strong candidate indicators for cumulative effects of OA, warming, and deoxygenation in marine ecosystems; and (3) to provide insight on incorporating pteropods into population and ecosystem models, which will help inform ecosystem-based management of marine resources under future environmental regimes.

Research paper thumbnail of The global distribution of pteropods and their contribution to carbonate and carbon biomass in the modern ocean

Earth System Science Data, 2012

Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns... more Pteropods are a group of holoplanktonic gastropods for which global biomass distribution patterns remain poorly described. The aim of this study was to collect and synthesise existing pteropod (Gymnosomata, Thecosomata and Pseudothecosomata) abundance and biomass data, in order to evaluate the global distribution of pteropod carbon biomass, with a particular emphasis on temporal and spatial patterns. We collected 25 939 data points from several online databases and 41 scientific articles. These data points corresponded to observations from 15 134 stations, where 93 % of observations were of shelled pteropods (Thecosomata) and 7 % of non-shelled pteropods (Gymnosomata). The biomass data has been gridded onto a 360 × 180 • grid, with a vertical resolution of 33 depth levels. Both the raw data file and the gridded data in NetCDF format can be downloaded from PANGAEA, doi:10.1594/PANGAEA.777387. Data were collected between 1950-2010, with sampling depths ranging from 0-2000 m. Pteropod biomass data was either extracted directly or derived through converting abundance to biomass with pteropod-specific length to carbon biomass conversion algorithms. In the Northern Hemisphere (NH), the data were distributed quite evenly throughout the year, whereas sampling in the Southern Hemisphere (SH) was biased towards winter and summer values. 86 % of all biomass values were located in the NH, most (37 %) within the latitudinal band of 30-60 • N. The range of global biomass values spanned over four orders of magnitude, with mean and median (non-zero) biomass values of 4.6 mg C m −3 (SD = 62.5) and 0.015 mg C m −3 , respectively. The highest mean biomass was located in the SH within the 70-80 • S latitudinal band (39.71 mg C m −3 , SD = 93.00), while the highest median biomass was in the NH, between 40-50 • S (0.06 mg C m −3 , SD = 79.94). Shelled pteropods constituted a mean global carbonate biomass of 23.17 mg CaCO 3 m −3 (based on non-zero records). Total biomass values were lowest in the equatorial regions and equally high at both poles. Pteropods were found at least to depths of 1000 m, with the highest biomass values located in the surface layer (0-10 m) and gradually decreasing with depth, with values in excess of 100 mg C m −3 only found above 200 m depth. Tropical species tended to concentrate at greater depths than temperate or high-latitude species. Global biomass levels in the NH were relatively invariant over the seasonal cycle, but more seasonally variable in the SH. The collected database provides a valuable tool for modellers for the study of marine ecosystem processes and global biogeochemical cycles. By extrapolating regional biomass to a global scale, we established global pteropod biomass to add up to 500 Tg C.