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Cold Regime interannual variability of primary and secondary producer community composition in the southeastern Bering Sea.

Stauffer BA, Miksis-Olds J, Goes JI - PLoS ONE (2015)

Bottom Line: Phytoplankton blooms stimulated different populations of secondary producers in each year, and summer consumer populations appeared to determine dominant populations in the subsequent spring.Overall, primary producers and secondary producers were more tightly coupled to each other and to hydrographic conditions in the coldest year compared to the warmer years.The highly variable nature of the interactions between the atmospherically-driven hydrographic environment, primary and secondary producers, and within food webs underscores the need to revisit how climatic regimes within the Bering Sea are defined and predicted to function given changing climate scenarios.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Paleo Environment, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, 10964, United States of America.

ABSTRACT
Variability of hydrographic conditions and primary and secondary productivity between cold and warm climatic regimes in the Bering Sea has been the subject of much study in recent years, while interannual variability within a single regime and across multiple trophic levels has been less well-documented. Measurements from an instrumented mooring on the southeastern shelf of the Bering Sea were analyzed for the spring-to-summer transitions within the cold regime years of 2009-2012 to investigate the interannual variability of hydrographic conditions, primary producer biomass, and acoustically-derived secondary producer and consumer abundance and community structure. Hydrographic conditions in 2012 were significantly different than in 2009, 2010, and 2011, driven largely by increased ice extent and thickness, later ice retreat, and earlier stratification of the water column. Primary producer biomass was more tightly coupled to hydrographic conditions in 2012 than in 2009 or 2011, and shallow and mid-column phytoplankton blooms tended to occur independent of one another. There was a high degree of variability in the relationships between different classes of secondary producers and hydrographic conditions, evidence of significant intra-consumer interactions, and trade-offs between different consumer size classes in each year. Phytoplankton blooms stimulated different populations of secondary producers in each year, and summer consumer populations appeared to determine dominant populations in the subsequent spring. Overall, primary producers and secondary producers were more tightly coupled to each other and to hydrographic conditions in the coldest year compared to the warmer years. The highly variable nature of the interactions between the atmospherically-driven hydrographic environment, primary and secondary producers, and within food webs underscores the need to revisit how climatic regimes within the Bering Sea are defined and predicted to function given changing climate scenarios.

No MeSH data available.


Related in: MedlinePlus

Map of the study area.Eastern Bering Sea and Gulf of Alaska, noting the location of the M2 mooring (circle), relevant seas and land areas.
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pone.0131246.g001: Map of the study area.Eastern Bering Sea and Gulf of Alaska, noting the location of the M2 mooring (circle), relevant seas and land areas.

Mentions: Mooring Site M2 is located at 56.86° N 164.06° W along the 70 m isobath of the continental shelf in the southeastern Bering Sea (Fig 1). The M2 moorings have been maintained since 1995 as part of the Eco-FOCI project (http://www.ecofoci.noaa.gov), which has also maintained mooring sites to the south and north of M2 [13,17]. The M2 mooring is composed of two subsurface moorings (oceanographic and acoustic) separated by approximately a kilometer to minimize noise from the oceanographic mooring chain and sensors in the acoustic recordings. The moorings were deployed sub-surface, allowing them to persist through ice-covered winters, and were typically recovered and re-deployed in early spring (April/May) and fall (September/October) of each year. The oceanographic mooring was equipped with CTDs (Sea-Bird Electronics, SBE-37), temperature (Sea-Bird Electronics, SBE-39), and nitrate (Satlantic, MBAI-ISUS VI) sensors at shallow (< 20 m), mid-column (20–40 m) and deep (> 40 m) depths. Shallow and mid-column chlorophyll a (Chl a) fluorometers (WET Labs, ECO Fluorometer) were located at depths of 11 m and 32 m. The factory calibration was used to convert chlorophyll fluorescence to Chl a. These are only estimates based on fluorescence of Chl a, as direct chlorophyll samples were only taken at the site during deployments and recoveries. Data were collected at least hourly, and all instruments were calibrated prior to deployment. The data were processed according to manufacturers’ specifications. A low pass filter (35-hour Lanczos squared) was applied to each of the oceanographic series [18], and the series were averaged over 6 hour intervals.


Cold Regime interannual variability of primary and secondary producer community composition in the southeastern Bering Sea.

Stauffer BA, Miksis-Olds J, Goes JI - PLoS ONE (2015)

Map of the study area.Eastern Bering Sea and Gulf of Alaska, noting the location of the M2 mooring (circle), relevant seas and land areas.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4482406&req=5

pone.0131246.g001: Map of the study area.Eastern Bering Sea and Gulf of Alaska, noting the location of the M2 mooring (circle), relevant seas and land areas.
Mentions: Mooring Site M2 is located at 56.86° N 164.06° W along the 70 m isobath of the continental shelf in the southeastern Bering Sea (Fig 1). The M2 moorings have been maintained since 1995 as part of the Eco-FOCI project (http://www.ecofoci.noaa.gov), which has also maintained mooring sites to the south and north of M2 [13,17]. The M2 mooring is composed of two subsurface moorings (oceanographic and acoustic) separated by approximately a kilometer to minimize noise from the oceanographic mooring chain and sensors in the acoustic recordings. The moorings were deployed sub-surface, allowing them to persist through ice-covered winters, and were typically recovered and re-deployed in early spring (April/May) and fall (September/October) of each year. The oceanographic mooring was equipped with CTDs (Sea-Bird Electronics, SBE-37), temperature (Sea-Bird Electronics, SBE-39), and nitrate (Satlantic, MBAI-ISUS VI) sensors at shallow (< 20 m), mid-column (20–40 m) and deep (> 40 m) depths. Shallow and mid-column chlorophyll a (Chl a) fluorometers (WET Labs, ECO Fluorometer) were located at depths of 11 m and 32 m. The factory calibration was used to convert chlorophyll fluorescence to Chl a. These are only estimates based on fluorescence of Chl a, as direct chlorophyll samples were only taken at the site during deployments and recoveries. Data were collected at least hourly, and all instruments were calibrated prior to deployment. The data were processed according to manufacturers’ specifications. A low pass filter (35-hour Lanczos squared) was applied to each of the oceanographic series [18], and the series were averaged over 6 hour intervals.

Bottom Line: Phytoplankton blooms stimulated different populations of secondary producers in each year, and summer consumer populations appeared to determine dominant populations in the subsequent spring.Overall, primary producers and secondary producers were more tightly coupled to each other and to hydrographic conditions in the coldest year compared to the warmer years.The highly variable nature of the interactions between the atmospherically-driven hydrographic environment, primary and secondary producers, and within food webs underscores the need to revisit how climatic regimes within the Bering Sea are defined and predicted to function given changing climate scenarios.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Paleo Environment, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, 10964, United States of America.

ABSTRACT
Variability of hydrographic conditions and primary and secondary productivity between cold and warm climatic regimes in the Bering Sea has been the subject of much study in recent years, while interannual variability within a single regime and across multiple trophic levels has been less well-documented. Measurements from an instrumented mooring on the southeastern shelf of the Bering Sea were analyzed for the spring-to-summer transitions within the cold regime years of 2009-2012 to investigate the interannual variability of hydrographic conditions, primary producer biomass, and acoustically-derived secondary producer and consumer abundance and community structure. Hydrographic conditions in 2012 were significantly different than in 2009, 2010, and 2011, driven largely by increased ice extent and thickness, later ice retreat, and earlier stratification of the water column. Primary producer biomass was more tightly coupled to hydrographic conditions in 2012 than in 2009 or 2011, and shallow and mid-column phytoplankton blooms tended to occur independent of one another. There was a high degree of variability in the relationships between different classes of secondary producers and hydrographic conditions, evidence of significant intra-consumer interactions, and trade-offs between different consumer size classes in each year. Phytoplankton blooms stimulated different populations of secondary producers in each year, and summer consumer populations appeared to determine dominant populations in the subsequent spring. Overall, primary producers and secondary producers were more tightly coupled to each other and to hydrographic conditions in the coldest year compared to the warmer years. The highly variable nature of the interactions between the atmospherically-driven hydrographic environment, primary and secondary producers, and within food webs underscores the need to revisit how climatic regimes within the Bering Sea are defined and predicted to function given changing climate scenarios.

No MeSH data available.


Related in: MedlinePlus