Carbonate chemistry in the microenvironment within cyanobacterial aggregates under present?day and future p CO 2 levels

Photosynthesis and respiration cause distinct chemical microenvironments within cyanobacterial aggregates. Here, we used microsensors a diffusion–reaction model to characterize gradients in carbonate chemistry investigate how these are affected by ocean acidification Baltic vs. Pacific aggregates (Nodularia Dolichospermum Trichodesmium). Microsensor measurements of O2 pH were performed under situ expected future pCO2 levels on Nodularia collected the Sea. Under conditions, covered ranges 80–175% air saturation 7.7–9.4 dark light, respectively. Carbon uptake light was predicted reduce HCO3? 100–150 ?mol L?1 CO2 3–6 aggregate center compared outside, inducing strong depletion (down 0.5 remaining center) even when assuming that 80–90% carbon uptake. enhanced availability allowed for significantly lower activity concentrating mechanisms, including reduction contribution up factor 10. The magnification proton elevated based buffer capacity observed despite concurrent decrease photosynthetic activity. In summary, provide quantitative image inorganic environment present-day considering both individual combined effects biological processes shape environments.