Climate Change Impacts on the Marine Cycling of Biogenic Sulfur: A Review

Abstract

A key component of the marine sulfur cycle is the climate-active gas dimethylsulfide (DMS), which is synthesized by a range of organisms from phytoplankton to corals, and accounts for up to 80% of global biogenic sulfur emissions. The DMS cycle starts with the intracellular synthesis of the non-gaseous precursor dimethylsulfoniopropionate (DMSP), which is released to the water column by various food web processes such as zooplankton grazing. This dissolved DMSP pool is rapidly turned over by microbially mediated conversion using two known pathways: demethylation (releasing methanethiol) and cleavage (producing DMS). Some of the formed DMS is ventilated to the atmosphere, where it undergoes rapid oxidation and contributes to the formation of sulfate aerosols, with the potential to affect cloud microphysics, and thus the regional climate. The marine phase cycling of DMS is complex, however, as heterotrophs also contribute to the consumption of the newly formed dissolved DMS. Interestingly, due to microbial consumption and other water column sinks such as photolysis, the amount of DMS that enters the atmosphere is currently thought to be a relatively minor fraction of the total amount cycled through the marine food web—less than 10%. These microbial processes are mediated by water column temperature, but the response of marine microbial assemblages to ocean warming is poorly characterized, although bacterial degradation appears to increase with an increase in temperature. This review will focus on the potential impact of climate change on the key microbially mediated processes in the marine cycling of DMS. It is likely that the impact will vary across different biogeographical regions from polar to tropical. For example, in the rapidly warming polar oceans, microbial communities associated with the DMS cycle will likely change dramatically during the 21st century with the decline in sea ice. At lower latitudes, where corals form an important source of DMS (P), shifts in the microbiome composition have been observed during thermal stress with the potential to alter the DMS cycle.

Retrospective Isotopic Analysis of Summertime Urban Atmospheric Sulfate in South Asia Using Improved Source Constraints

“…However, given the order(s) of magnitude difference between the anthropogenic sulfur compound reservoirs and biogenic emissions (from landfills, swamps, and so on) in megacity environments, such contributions are expectedly negligible. Here, as in studies from similar polluted environments, , and based on the weak soil microbial activity − and the low biogenic flux estimates of sulfur compounds in inland soils, , the contribution of biogenic sulfur is considered insignificant (i.e., f Bio = 0 in eq ). Secondly, it has been reported that K + accounts for a maximum of 5%, while SO 4 2– accounts for ∼1% in fresh biomass burning-derived particles from various biomes .…”

Time to establish an international vaccine candidate pool for potential highly infectious respiratory disease: a community’s view

“…Evidence suggests that the occurrence of such pandemics may become more frequent in the near future. 15 , 16 Thus, according to the WHO and the US CDC there are several pathogens that could cause future pandemics including Crimean-Cong haemorrhagic fever, Ebola virus disease and Marburgh virus disease, Lassa fever, Middle East respiratory syndrome (MERS), Nipah and henipaviral disease, Rift Valley fever, Zika virus, Disease X, Cholera, Polio, Enterovirus-71, high drug-resistant Tuberculosis and avian influenza H5N1. 17 , 18 For example, as this manuscript is written the avian influenza H5N1 is subject of close surveillance by the WHO and the Institute of Public Health of Chile where last March 2023 was reported a human infection of avian influenza H5N1.…”

The Effect of Zooplankton on the Distributions of Dimethyl Sulfide and Dimethylsulfoniopropionate in the Bohai and Yellow Seas

“…Many studies have focused on the temporal and spatial distributions and transformation of DMS and DMSP in the surface seawater and the sea‐to‐air exchange, as well as the effects of some environmental factors on these sulfur compounds (Jackson & Gabric, 2022; Kiene, 1992; O'Brien et al., 2022; Owen et al., 2021; Shemi et al., 2021; Yang et al., 2011; Yu et al., 2021). The Bohai Sea (BS) and Yellow Sea (YS) are marginal seas located in the western Pacific Ocean that comprise a total area of 460,000 km 2 (Chen et al., 2022).…”