Abstract:

Diatoms are an important phytoplankton group in this region as they can dominate both the standing stock of phytoplankton and the rate of primary production at times. Unlike other phytoplankton groups, diatoms have an obligate requirement for silicon. Because diatoms can be important to regional primary production, there can be a strong coupling between the regional C and Si cycles. Because of this coupling, measurement of biogenic silica (bSi) production is a useful proxy to deduce the diatom-specific contribution to community rates, as silicoflagellates and radiolarians (which both use Si to build shells) are comparatively minor in biomass and grow slower than diatoms. Data were collected during cruises PTS02 and PTS03 on the Mississippi-Alabama shelf from March-July, 2016. This dataset supports the publication: Dzwonkowski, B., Greer, A.T., Briseño-Avena, C., Krause, J.W., Soto, I.M., Hernandez, F.J., Deary, A.L., Wiggert, J.D., Joung, D., Fitzpatrick, P.J., O'Brien, S.J., Dykstra, S.L., Lau, Y., Cambazoglu, M.K., Lockridge, G., Howden, S.D., Shiller, A.M., and Graham, W.M. (2017). Estuarine influence on biogeochemical properties of the Alabama shelf during the fall season. Continental Shelf Research, 140: 96-109 doi: 10.1016/j.csr.2017.05.001. Related size-fractionated nitrate uptake and primary productivity data can be found in GRIIDC dataset R4.x260.000:0092.

Suggested Citation:

Krause, Jeffrey W.; Acton, Sydney. 2018. Biogenic silica standing stock and productivity on the Mississippi-Alabama Shelf, March to July, 2016. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N70K2738

Publications:

Dzwonkowski, B., Greer, A. T., Briseño-Avena, C., Krause, J. W., Soto, I. M., Hernandez, F. J., … Graham, W. M. (2017). Estuarine influence on biogeochemical properties of the Alabama shelf during the fall season. Continental Shelf Research, 140, 96–109. doi:10.1016/j.csr.2017.05.001

Purpose:

Rates of biological productivity were determined through a consortia partnership with the Alabama Center for Ecological Resilience (ACER) and Consortium for Oil Spill Exposure Pathways in Coastal River-Dominated Ecosystems (CONCORDE). The shared goal for each consortium was to understand the spatial and temporal variability in biological productivity rates. This information is critical for providing baseline information to understanding the potential effects of anthropogenic (e.g. oil spill) or natural (e.g. hurricane) disturbances on biological productivity in the Mississippi-Alabama shelf in the northern Gulf of Mexico.

Data Parameters and Units:

Cruise (PTS=Point Sur R/V), Event number (yyyymmddhhhh), Local time (hhhh), Type (Activity), Station, Latitude (degrees N), Latitude (decimal minutes), Longitude (degrees W), Longitude (decimal minutes), Bottom depth (m), Target depth (m), Biogenic silica (bSi, umol Si/L), Lithogenic silica (LSi, umol Si/L), Gross rate of biogenic silica production (32Si rho, umol Si/L/d), Biomass-normalized silica production rates (32Si Vb (per day) No data is denoted as -999 Analytical zero values are denoted as 0 Naming conventions are as in: Brzezinski, M.A. and Phillips, D.R. (1997). Evaluation of 32Si as a tracer for measuring silica production rates in marine waters. Limnology and Oceanography, 42(5): 856-865 doi: 10.4319/lo.1997.42.5.0856 Krause, J.W., Brzezinski, M.A., and Jones, J.L. (2011). Application of low-level beta counting of 32Si for the measurement of silica production rates in aquatic environments. Marine Chemistry, 127(1-4): 40-47 doi: 10.1016/j.marchem.2011.07.001

Methods:

Methods are published in Dzwonkowski, B., Greer, A.T., Briseño-Avena, C., Krause, J.W., Soto, I.M., Hernandez, F.J., Deary, A.L., Wiggert, J.D., Joung, D., Fitzpatrick, P.J., O'Brien, S.J., Dykstra, S.L., Lau, Y., Cambazoglu, M.K., Lockridge, G., Howden, S.D., Shiller, A.M., and Graham, W.M. (2017). Estuarine influence on biogeochemical properties of the Alabama shelf during the fall season. Continental Shelf Research, 140: 96-109 doi: 10.1016/j.csr.2017.05.001

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