Biogeochemical processes in Amazon shelf waters: chemical distributions and uptake rates of silicon, carbon and nitrogen

A Synoptic Assessment of the Amazon River-Ocean Continuum during Boreal Autumn: From Physics to Plankton Communities and Carbon Flux

“…As the change in TA due to carbonate mineral production is twice as large as the change in DIC (Skirrow, 1975 ) and by neglecting the small changes in TA due to the production and decay of organic matter (Brewer and Goldman, 1976 ), the organic carbon production corrected for calcification is 82-71/2 = 46 μmol kg −1 . Thus, and inorganic uptake exhibit a molar ratio of /DIC = 0.9, which is beyond the range (0.15–0.4) of molar silicon/carbon production ratios reported by DeMaster et al ( 1996 ) and Ternon et al ( 2000 ) in waters of the Amazon shelf. This high value (0.9), in comparison to the mean value of 0.13 for low-latitude diatoms (Brzezinski, 1985 ), highlights the dominant role of diatoms (mainly Fragillaria sp .…”

“…The oxygen supersaturation in the river plume (negative AOU) is evidence of high photosynthetic activity. Other authors (DeMaster et al, 1996 ; DeMaster and Aller, 2001 ; Garcia et al, 2006 ) also reported negative AOU values.…”

A Synoptic Assessment of the Amazon River-Ocean Continuum during Boreal Autumn: From Physics to Plankton Communities and Carbon Flux

“…As the change in TA due to carbonate mineral production is twice as large as the change in DIC (Skirrow, 1975 ) and by neglecting the small changes in TA due to the production and decay of organic matter (Brewer and Goldman, 1976 ), the organic carbon production corrected for calcification is 82-71/2 = 46 μmol kg −1 . Thus, and inorganic uptake exhibit a molar ratio of /DIC = 0.9, which is beyond the range (0.15–0.4) of molar silicon/carbon production ratios reported by DeMaster et al ( 1996 ) and Ternon et al ( 2000 ) in waters of the Amazon shelf. This high value (0.9), in comparison to the mean value of 0.13 for low-latitude diatoms (Brzezinski, 1985 ), highlights the dominant role of diatoms (mainly Fragillaria sp .…”

“…The oxygen supersaturation in the river plume (negative AOU) is evidence of high photosynthetic activity. Other authors (DeMaster et al, 1996 ; DeMaster and Aller, 2001 ; Garcia et al, 2006 ) also reported negative AOU values.…”

Measuring production—dissolution rates of marine biogenic silica by 30Si‐isotope dilution using a high‐resolution sector field inductively coupled plasma mass spectrometer

“…These standard deviations are satisfactory given the usual temporal and/or spatial range of the production and dissolution rates measured in coastal and/or open ocean ecosystems (Nelson and Goering 1977a, b;Nelson et al 1981;Nelson and Gordon 1982;Brzezinski and Nelson 1989;Nelson et al 1995;Brzezinski et al 2001Brzezinski et al , 2003DeMaster et al 1996;Beucher et al 2004a, b). The two different models described above give similar precision, as described in Elskens et al (2007), independently if we use 30 Si or 28 Si (Table 6).…”

A Shift in the Biogenic Silica of Sediment in the Larsen B Continental Shelf, Off the Eastern Antarctic Peninsula, Resulting from Climate Change

“…2 ) for the Antarctic context (including the Weddell and Ross Seas and the Bransfield and Gerlache Straits), where dry weight percentages varied between 1% and 49% in surface sediments [31], [32], [33], [34]. Based on the frustule and spicule volumes and the biogenic silica density, less than ∼14% (LBC station, from 0 to 0.5 cm depth) of the total biogenic silica in our samples was from diatoms or sponge spicules ( Fig.…”

A Synoptic Assessment of the Amazon River-Ocean Continuum during Boreal Autumn: From Physics to Plankton Communities and Carbon Flux

“…As the change in TA due to carbonate mineral production is twice as large as the change in DIC (Skirrow, 1975 ) and by neglecting the small changes in TA due to the production and decay of organic matter (Brewer and Goldman, 1976 ), the organic carbon production corrected for calcification is 82-71/2 = 46 μmol kg −1 . Thus, and inorganic uptake exhibit a molar ratio of /DIC = 0.9, which is beyond the range (0.15–0.4) of molar silicon/carbon production ratios reported by DeMaster et al ( 1996 ) and Ternon et al ( 2000 ) in waters of the Amazon shelf. This high value (0.9), in comparison to the mean value of 0.13 for low-latitude diatoms (Brzezinski, 1985 ), highlights the dominant role of diatoms (mainly Fragillaria sp .…”

“…The oxygen supersaturation in the river plume (negative AOU) is evidence of high photosynthetic activity. Other authors (DeMaster et al, 1996 ; DeMaster and Aller, 2001 ; Garcia et al, 2006 ) also reported negative AOU values.…”

Measuring production—dissolution rates of marine biogenic silica by 30Si‐isotope dilution using a high‐resolution sector field inductively coupled plasma mass spectrometer

“…These standard deviations are satisfactory given the usual temporal and/or spatial range of the production and dissolution rates measured in coastal and/or open ocean ecosystems (Nelson and Goering 1977a, b;Nelson et al 1981;Nelson and Gordon 1982;Brzezinski and Nelson 1989;Nelson et al 1995;Brzezinski et al 2001Brzezinski et al , 2003DeMaster et al 1996;Beucher et al 2004a, b). The two different models described above give similar precision, as described in Elskens et al (2007), independently if we use 30 Si or 28 Si (Table 6).…”

A Shift in the Biogenic Silica of Sediment in the Larsen B Continental Shelf, Off the Eastern Antarctic Peninsula, Resulting from Climate Change

“…2 ) for the Antarctic context (including the Weddell and Ross Seas and the Bransfield and Gerlache Straits), where dry weight percentages varied between 1% and 49% in surface sediments [31], [32], [33], [34]. Based on the frustule and spicule volumes and the biogenic silica density, less than ∼14% (LBC station, from 0 to 0.5 cm depth) of the total biogenic silica in our samples was from diatoms or sponge spicules ( Fig.…”

A Synoptic Assessment of the Amazon River-Ocean Continuum during Boreal Autumn: From Physics to Plankton Communities and Carbon Flux

“…As the change in TA due to carbonate mineral production is twice as large as the change in DIC (Skirrow, 1975 ) and by neglecting the small changes in TA due to the production and decay of organic matter (Brewer and Goldman, 1976 ), the organic carbon production corrected for calcification is 82-71/2 = 46 μmol kg −1 . Thus, and inorganic uptake exhibit a molar ratio of /DIC = 0.9, which is beyond the range (0.15–0.4) of molar silicon/carbon production ratios reported by DeMaster et al ( 1996 ) and Ternon et al ( 2000 ) in waters of the Amazon shelf. This high value (0.9), in comparison to the mean value of 0.13 for low-latitude diatoms (Brzezinski, 1985 ), highlights the dominant role of diatoms (mainly Fragillaria sp .…”

“…The oxygen supersaturation in the river plume (negative AOU) is evidence of high photosynthetic activity. Other authors (DeMaster et al, 1996 ; DeMaster and Aller, 2001 ; Garcia et al, 2006 ) also reported negative AOU values.…”

Measuring production—dissolution rates of marine biogenic silica by 30Si‐isotope dilution using a high‐resolution sector field inductively coupled plasma mass spectrometer

“…These standard deviations are satisfactory given the usual temporal and/or spatial range of the production and dissolution rates measured in coastal and/or open ocean ecosystems (Nelson and Goering 1977a, b;Nelson et al 1981;Nelson and Gordon 1982;Brzezinski and Nelson 1989;Nelson et al 1995;Brzezinski et al 2001Brzezinski et al , 2003DeMaster et al 1996;Beucher et al 2004a, b). The two different models described above give similar precision, as described in Elskens et al (2007), independently if we use 30 Si or 28 Si (Table 6).…”

A Shift in the Biogenic Silica of Sediment in the Larsen B Continental Shelf, Off the Eastern Antarctic Peninsula, Resulting from Climate Change

“…2 ) for the Antarctic context (including the Weddell and Ross Seas and the Bransfield and Gerlache Straits), where dry weight percentages varied between 1% and 49% in surface sediments [31], [32], [33], [34]. Based on the frustule and spicule volumes and the biogenic silica density, less than ∼14% (LBC station, from 0 to 0.5 cm depth) of the total biogenic silica in our samples was from diatoms or sponge spicules ( Fig.…”