Rising concentrations of atmospheric CO₂ results in higher equilibrium concentrations of dissolved CO₂ in natural waters, with corresponding increases in hydrogen ion and bicarbonate concentrations and decreases in hydroxyl ion and carbonate concentrations. Superimposed on these climate change effects is the dynamic nature of carbon cycling in coastal zones, which can lead to seasonal and diel changes in pH and CO₂ concentrations that can exceed changes expected for open ocean ecosystems by the end of the century. Among harmful algae, i.e. some species and/or strains of Cyanobacteria, Dinophyceae, Prymnesiophyceae, Bacillariophyceae, and Ulvophyceae, the occurrence of a CO₂ concentrating mechanisms (CCMs) is the most frequent mechanism of inorganic carbon acquisition in natural waters in equilibrium with the present atmosphere (400 μmol CO₂ mol⁻¹ total gas), with varying phenotypic modification of the CCM. No data on CCMs are available for Raphidophyceae or the brown tide Pelagophyceae. Several HAB species and/or strains respond to increased CO₂ concentrations with increases in growth rate and/or cellular toxin content, however, others are unaffected. Beyond the effects of altered C concentrations and speciation on HABs, changes in pH in natural waters are likely to have profound effects on algal physiology. This review outlines the implications of changes in inorganic cycling for HABs in coastal zones, and reviews the knowns and unknowns with regard to how HABs can be expected to ocean acidification. We further point to the large regions of uncertainty with regard to this evolving field.

大气中CO ₂浓度的升高会导致天然水中溶解的CO _2的平衡浓度更高，相应地，氢离子和碳酸氢根的浓度会相应增加，而氢氧根和碳酸盐的浓度会相应降低。在这些气候变化影响上叠加的是沿海地区碳循环的动态性质，这可能导致pH和CO ₂浓度的季节性变化和狄尔变化，到本世纪末可能超过开放海洋生态系统的预期变化。在有害藻类中，即蓝藻属，藻科，白藻科，芽孢杆菌科和藻科的某些物种和/或菌株中，CO ₂的发生浓缩机制（CCMs）是在自然水中在与当前大气（400μmolCO ₂ mol ^-1总气体）平衡的情况下最常见的无机碳获取机制，并且CCM的表型发生了变化。没有关于蝶藻科或褐潮蝶科的CCM的数据。几种HAB物种和/或菌株对增加的CO ₂作出响应浓度随生长速率和/或细胞毒素含量的增加而增加，但是其他浓度不受影响。除了改变碳浓度和形态对HABs的影响外，天然水中pH值的变化还可能对藻类生理产生深远的影响。这篇综述概述了无机循环变化对沿海地区HABs的影响，并回顾了如何预期HABs会导致海洋酸化的已知和未知。我们进一步指出，在这个不断发展的领域中，存在很大的不确定性区域。