Total alkalinity: The explicit conservative expression and its application to biogeochemical processes

Wolf-Gladrow, Dieter; Zeebe, Richard E.; Klaas, Christine; Körtzinger, Arne; Dickson, Andrew G.

doi:10.1016/j.marchem.2007.01.006

Cited by 527 publications

(494 citation statements)

References 19 publications

Supporting

Mentioning

478

Contrasting

Unclassified

Order By: Relevance

“…colonies was 10-to 100-fold lower than that of the potential DIC flux, although these colonies belong to the most productive microenvironments reported in aquatic systems (Ploug et al, 2010). Bicarbonate uptake in cyanobacterial cells must be accompanied either by uptake of H þ or by excretion of OH À to keep balance of charges (Wolf-Gladrow et al, 2007). High uptake rates of H þ are problematic at alkaline pH as shown using a kinetic model of the marine carbonate system (Wolf-Gladrow and Riebesell, 1997;WolfGladrow et al, 1999).…”

Section: Discussionmentioning

confidence: 93%

Carbon, nitrogen and O2 fluxes associated with the cyanobacterium Nodularia spumigena in the Baltic Sea

et al. 2011

View full text Add to dashboard Cite

Photosynthesis, respiration, N 2 fixation and ammonium release were studied directly in Nodularia spumigena during a bloom in the Baltic Sea using a combination of microsensors, stable isotope tracer experiments combined with nanoscale secondary ion mass spectrometry (nanoSIMS) and fluorometry. Cell-specific net C-and N 2 -fixation rates by N. spumigena were 81.6±6.7 and 11.4 ± 0.9 fmol N per cell per h, respectively. During light, the net C:N fixation ratio was 8.0 ± 0.8. During darkness, carbon fixation was not detectable, but N 2 fixation was 5.4 ± 0.4 fmol N per cell per h. Net photosynthesis varied between 0.34 and 250 nmol O 2 h À1 in colonies with diameters ranging between 0.13 and 5.0 mm, and it reached the theoretical upper limit set by diffusion of dissolved inorganic carbon to colonies (41 mm). Dark respiration of the same colonies varied between 0.038 and 87 nmol O 2 h À1 , and it reached the limit set by O 2 diffusion from the surrounding water to colonies (41 mm). N 2 fixation associated with N. spumigena colonies (41 mm) comprised on average 18% of the total N 2 fixation in the bulk water. Net NH 4 þ release in colonies equaled 8-33% of the estimated gross N 2 fixation during photosynthesis. NH 4 þ concentrations within light-exposed colonies, modeled from measured net NH 4 þ release rates, were 60-fold higher than that of the bulk. Hence, N. spumigena colonies comprise highly productive microenvironments and an attractive NH 4 þ microenvironment to be utilized by other (micro)organisms in the Baltic Sea where dissolved inorganic nitrogen is limiting growth.

show abstract

Section: Discussionmentioning

confidence: 93%

Carbon, nitrogen and O2 fluxes associated with the cyanobacterium Nodularia spumigena in the Baltic Sea

et al. 2011

View full text Add to dashboard Cite

show abstract

“…10a). It is well known 38 that in neutral and basic conditions, HCO 3 À and CO 3 2 À are the dominant species, respectively. However, our quantum molecular dynamics simulations reveal that in acidic environment, similar to our experimental conditions (pHo4), the [EMIM-CO 2 ] þ complex remains stable (Supplementary Fig.…”

Section: Discussionmentioning

confidence: 99%

Robust carbon dioxide reduction on molybdenum disulphide edges

et al. 2014

View full text Add to dashboard Cite

“…The pH electrode was calibrated on the total scale using Tris/HCl and 2-aminopyridine/HCl buffer solutions with a salinity of 38 (Dickson and co-workers [35]). Measurements were carried out in triplicate at 258C with pre-weighed samples of ca 25 g and 0.1 N HCl (TitriPAC, Merck) was used for titration.…”

Section: Methodsmentioning

confidence: 99%

“…Measurements were carried out in triplicate at 258C with pre-weighed samples of ca 25 g and 0.1 N HCl (TitriPAC, Merck) was used for titration. A T was calculated as described by Dickson and co-workers [35]. Standards provided by Dickson (batch 99 and 102) were run regularly.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Calcification rates and the effect of ocean acidification on Mediterranean cold-water corals

et al. 2011

View full text Add to dashboard Cite

Global environmental changes, including ocean acidification, have been identified as a major threat to scleractinian corals. General predictions are that ocean acidification will be detrimental to reef growth and that 40 to more than 80 per cent of present-day reefs will decline during the next 50 years. Coldwater corals (CWCs) are thought to be strongly affected by changes in ocean acidification owing to their distribution in deep and/or cold waters, which naturally exhibit a CaCO 3 saturation state lower than in shallow/warm waters. Calcification was measured in three species of Mediterranean cold-water scleractinian corals (Lophelia pertusa, Madrepora oculata and Desmophyllum dianthus) on-board research vessels and soon after collection. Incubations were performed in ambient sea water. The species M. oculata was additionally incubated in sea water reduced or enriched in CO 2. At ambient conditions, calcification rates ranged between 20.01 and 0.23% d 21 . Calcification rates of M. oculata under variable partial pressure of CO 2 (pCO 2 ) were the same for ambient and elevated pCO 2 (404 and 867 matm) with 0.06 + 0.06% d 21 , while calcification was 0.12 + 0.06% d 21 when pCO 2 was reduced to its pre-industrial level (285 matm). This suggests that present-day CWC calcification in the Mediterranean Sea has already drastically declined (by 50%) as a consequence of anthropogenic-induced ocean acidification.

show abstract

Total alkalinity: The explicit conservative expression and its application to biogeochemical processes

Cited by 527 publications

References 19 publications

Carbon, nitrogen and O2 fluxes associated with the cyanobacterium Nodularia spumigena in the Baltic Sea

Carbon, nitrogen and O2 fluxes associated with the cyanobacterium Nodularia spumigena in the Baltic Sea

Robust carbon dioxide reduction on molybdenum disulphide edges

Calcification rates and the effect of ocean acidification on Mediterranean cold-water corals

Contact Info

Product

Resources

About