Chemical characterization of Punta de Fuencaliente CO<sub>2</sub> seeps system (La Palma Island, NE Atlantic Ocean): a new natural laboratory for ocean acidification studies

Abstract

Abstract. We present a new natural carbon dioxide (CO2) system located off the southern coast of La Palma Island (Canary Islands, Spain). Like others CO2 seeps, these seeps can be used as an analogue to study the effects of ocean acidification (OA) on the marine realm. With this aim, we present an accurate chemical characterization of the seeps system carbon emissions, describing the carbon system dynamics, by measuring pH, AT and CT, as well as, Ω aragonite and calcite. Our explorations on the area have found several emission points with similar chemical features. Here, the CO2 emission flux varies between 2.8 kg CO2 d−1 to 28 kg CO2 d−1, becoming a significant source of carbon. CO2 seeps are of volcanic origin and the alteration of local ocean chemistry is due to acid brackish water discharges. Although this kind of acidified system is not a perfect image of future oceans, this area of La Palma island is an exceptional spot to perform studies aimed to understand the effect of different levels of OA on the functioning of marine ecosystems. These studies can then be used to comprehend how life has persisted through past Eras, with higher atmospheric CO2, or to predict the consequences of present fossil fuel usage on the marine ecosystem of the future oceans.

Submarine Groundwater Discharge in the Northern Bohai Sea, China: Implications for Coastal Carbon Budgets and Buffering Capacity

“…In the South China shelf scale, the negative correlation between radium isotopes and pH became more pronounced (Figures 10c and 10d, Wang et al., 2021b), further supporting that SGD can acidify local seawater and affect seawater biogeochemistry. Similar observations were also found in coastal reef systems (Cyronak et al., 2014; Wang et al., 2014), volcanic islands (González‐Delgado et al., 2021; Lee & Kim, 2015) and sandy beaches (Liu et al., 2021).…”

Characterization of undocumented CO2hydrothermal vent’s system in the Mediterranean Sea: implications for ocean acidification forecasting

“…For this reason, hydrothermal ecosystems are increasingly used as natural laboratories to analyse biological and physiological responses at species and community levels to OA [16, 17]. In addition, the lowering of pH, typical of these areas, generates a complex set of environmental features, such as oxygen reduction, alteration of nutrients and of species interaction that are usually difficult to reproduce in mesocosms [18, 19].…”

“…A few other systems have been described recently [15, 26, 27]. There is a relatively large body of research on the species and communities inhabiting shallow hydrothermal vents characterized by OA conditions, and also a few reviews on the main structural changes showing a general reduction of taxonomic and functional diversity in the areas of major venting and critical low pH conditions [13, 16, 24].…”