Cumulative climatic stressors strangles marine aquaculture: Ancillary effects of COVID 19 on Spanish mariculture

Marine aquaculture takes advantage of marine ecosystem services to produce goods that can be relevant from a food security point of view. However, this activity is subject to multiple stressors as the ones exerted by global climate change. Local stressed conditions due to environmental drivers may be exacerbated by the COVID19 pandemic crisis. In this paper we analyze the pre-COVID-19 situation in two Spanish regions with the highest aquaculture production, Galicia and the Valencian Community. The incidence of storms, heat waves and mussel farming closure were analyzed, and surveys were used to define the perception of producers in terms of economic problems derived from COVID-19 and synergistic environmental concerns. Also the temporal trend of mussel production was analyzed. Spanish marine aquaculture has been intensively subjected to climatic stressors that made it more vulnerable to COVID-19, showing some weakness in terms of production as can be seen in mussel production and fresh consumption. Anyway, extensive aquaculture and aquaculture developed by Integrated Multi-Trophic Aquaculture (IMTA) was reported as somewhat more resilient to the impact of COVID-19. In order to ensure the environmental and economic sustainability of marine aquaculture - under a future uncertain pandemic scenario – our outcomes underline the need for more resilient adaptation programs and recovery plans taking into account the climate change effects.M.C.M.’s research activity was supported by the European Union’s Horizon 2020 Research and Innovation programme under the Marie Skłodowska-Curie Action (Grant agreement no. 835589, MIRROR Project)

Surface CO₂ measurements in the English Channel and Southern Bight of North Sea using voluntary observing ships

Ships of opportunity have been used to investigate ocean–atmosphere CO2 fluxes in the English Channel and Southern Bight of the North Sea. Continuous underway measurements of the fugacity of seawater carbon dioxide (fCO2sw), chlorophyll, temperature and salinity have been performed along 26 transects during the spring and autumn periods. The spatial fCO2sw distribution along the Channel and Southern Bight is modulated by the photosynthetic activity, temperature changes and water mixing between inputs from the North Atlantic Ocean and riverine discharges. The seasonal variability of fCO2sw is assessed and discussed in terms of the biology and temperature effects, these having similar impacts. The variation of fCO2sw shows similar interannual patterns, with lower values in spring. The annual average of air–sea CO2 fluxes places the English Channel as neutral area of CO2 uptake. The spring and autumn data allow differentiating between distal and proximal continental areas. The Southern Bight shows a tendency towards net CO2 uptake on the distal continental shelf, whereas the Scheldt and Thames Plumes show a CO2 source behaviour on the proximal continental shelves