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The Science of the Total Environment Nov 2022Aquaculture is a globally expanding industry that contributes to feeding an increasing global population. Shellfish cultivation is one of the largest sectors of...
Aquaculture is a globally expanding industry that contributes to feeding an increasing global population. Shellfish cultivation is one of the largest sectors of aquaculture and one of the few food productions that have the potential capacity of acting as carbon sink. In fact, >90 % of bivalve shells are calcium carbonate (CaCO), synthetized during biocalcification process, which incorporates a molecule of CO. Manila clam (Venerupis philippinarum, Adams & Reeves, 1850) and Mediterranean mussel (Mytilus galloprovincialis, Lamarck, 1819) are two of the major groups of cultivated shellfish. Our aim was to assess the potential role of those two bivalve species in the overall marine carbon balance using an ecosystem approach, and to evaluate if they can be definitely regarded as carbon sink. The contribution to CO emissions (as CO eq./kg of fresh products) due to mollusk farming has been also calculated as carbon-source term by means of Life Cycle Assessment (LCA). LCA is nowadays the most shared and accepted tool for evaluating the environmental impacts of aquaculture productions. As a case study, the Sacca di Goro coastal lagoon (Northern Adriatic Sea, Italy) has been considered, because it is the premier site in Europe for clam farming, and one of the most important for mussels. Our study has shown that for each kilogram of harvested and packaged clams and mussels, shell formation throughout the mollusk growth allows to permanently capture 254 and 146 g of CO, in the face of 22 and 55 g CO eq. emitted for farming, respectively. As a result, clams and mussel aquaculture could be considered as a carbon sink, with a net carbon capture capacity of 233 and 91 g CO/kg of fresh product, respectively. In a wider context, bivalve aquaculture could be included in the carbon trading system and played a role towards the carbon-neutral economy.
Topics: Animals; Aquaculture; Bivalvia; Calcium Carbonate; Carbon; Carbon Dioxide; Carbon Sequestration; Ecosystem; Mytilus
PubMed: 35870589
DOI: 10.1016/j.scitotenv.2022.157508 -
Biology Letters Oct 2018Blue carbon did not originally include macroalgal ecosystems; however evidence is mounting that macroalgal ecosystems function in marine carbon sequestration. The great... (Review)
Review
Blue carbon did not originally include macroalgal ecosystems; however evidence is mounting that macroalgal ecosystems function in marine carbon sequestration. The great majority of present day marine macroalgal net primary productivity (NPP) involves haptophytic algae on eroding shores. For these organisms the long-term storage of particulate organic carbon involves export from the site of production of biomass that has evaded parasites and grazers, and that some of the exported biomass is sedimented and stored rather than being mineralized by detritivores (microbes and fauna). Export from eroding shores, and subsequent storage, of haptophytic marine macroalgal particulate organic carbon could have started by 1.6 Ga. Storage on depositing shores close to the site of NPP by rhizophytic macroalgae and then by rhizophytic coastal seagrasses, tidal marshes and mangroves began not less than 209 Ma ago. Future increases in surface ocean temperatures may bring tropical marine macroalgae to their upper temperature limit, while temperate marine macroalgae will migrate poleward, in both cases assuming that temperature increases faster than genetic adaptation to higher temperature. Increased CO in the surface ocean will generally favour uncalcified over calcified marine macroalgae. This results in decreased CO release from decreased calcification, as well as decreased ballasting by CaCO of exported particulate organic carbon resulting in decreasing sedimentation. While much more work is needed, the available information suggests that macroalgae play a significant role in marine organic carbon storage.
Topics: Calcium Carbonate; Carbon; Carbon Dioxide; Carbon Sequestration; Ecosystem; Geologic Sediments; Plants; Seawater; Seaweed; Temperature; Wetlands
PubMed: 30282745
DOI: 10.1098/rsbl.2018.0336 -
PloS One 2023Carbon sequestration as influenced by management practices such as soil amendments is not yet fully understood. Gypsum and crop residues can improve soil properties, but...
Carbon sequestration as influenced by management practices such as soil amendments is not yet fully understood. Gypsum and crop residues can improve soil properties, but few studies have focused on their combined effect on soil C fractions. The objective of this greenhouse study was to determine how treatments affected different forms of C, i.e., total C, permanganate oxidizable C (POXC), and inorganic C in 5 soil layers (0-2, 2-4, 4-10, 10-25, and 25-40 cm). Treatments were glucose (4.5 Mg ha-1), crop residues (13.4 Mg ha-1), gypsum (26.9 Mg ha-1) and an untreated control. Treatments were applied to two contrasting soil types in Ohio (USA)-Wooster silt loam and Hoytville clay loam. The C measurements were made one year after the treatment applications. Total C and POXC contents were significantly higher in Hoytville soil as compared to Wooster soil (P < 0.05). Across both Wooster and Hoytville soils, the addition of glucose increased total C significantly by 7.2% and 5.9% only in the top 2 cm and 4 cm layers of soil, respectively, compared to the control treatment, and residue additions increased total C from 6.3-9.0% in various soil layers to a depth of 25 cm. Gypsum addition did not affect total C concentrations significantly. Glucose addition resulted in a significant increase in calcium carbonate equivalent concentrations in the top 10 cm of Hoytville soil only, and gypsum addition significantly (P < 0.10) increased inorganic C, as calcium carbonate equivalent, in the lowest layer of the Hoytville soil by 32% compared to the control. The combination of glucose and gypsum increased inorganic C levels in Hoytville soils by creating sufficient amounts of CO2 that then reacted with Ca within the soil profile. This increase in inorganic C represents an additional way C can be sequestered in soil.
Topics: Soil; Carbon; Calcium Sulfate; Ohio; Calcium Carbonate
PubMed: 37014898
DOI: 10.1371/journal.pone.0283722 -
Scientific Reports May 2022The oxygen isotope compositions of carbonate and phosphatic fossils hold the key to understanding Earth-system evolution during the last 500 million years....
The oxygen isotope compositions of carbonate and phosphatic fossils hold the key to understanding Earth-system evolution during the last 500 million years. Unfortunately, the validity and interpretation of this record remain unsettled. Our comprehensive compilation of Phanerozoic δO data for carbonate and phosphate fossils and microfossils (totaling 22,332 and 4615 analyses, respectively) shows rapid shifts best explained by temperature change. In calculating paleotemperatures, we apply a constant hydrosphere δO, correct seawater δO for ice volume and paleolatitude, and correct belemnite δO values for O enrichment. Similar paleotemperature trends for carbonates and phosphates confirm retention of original isotopic signatures. Average low-latitude (30° S-30° N) paleotemperatures for shallow environments decline from 42.0 ± 3.1 °C in the Early-to-Middle Ordovician to 35.6 ± 2.4 °C for the Late Ordovician through the Devonian, then fluctuate around 25.1 ± 3.5 °C from the Mississippian to today. The Early Triassic and Middle Cretaceous stand out as hothouse intervals. Correlations between atmospheric CO forcing and paleotemperature support CO's role as a climate driver in the Paleozoic.
Topics: Carbon Dioxide; Carbonates; Oceans and Seas; Phosphates; Seawater; Temperature
PubMed: 35624298
DOI: 10.1038/s41598-022-11493-1 -
PloS One 2022In karst regions, the majority of studies have focused on ecosystem carbon sequestration in the same lithology, but no studies in different lithologies. In this study,...
In karst regions, the majority of studies have focused on ecosystem carbon sequestration in the same lithology, but no studies in different lithologies. In this study, actual measurements were used to reveal carbon sequestration characteristics of two plantation forest ecosystems (Bodinieri cinnamon and Cupressus funebris) with different lithologies of karst. The results showed that the tree layer showed the highest vegetation biomass, carbon content, carbon density, and ratio of aboveground biomass to belowground biomass. The carbon density of B. cinnamon plantation and C. funebris plantation was high in dolomite and in limestone respectively. The soil quality and carbon density of bare ground and plantation varied across different lithologies. The carbon density of various ecosystem components was in the order of vegetation>soil>litterfall. The carbon density and net carbon density of plantation varied across different lithologies. In B. cinnamon plantation, the carbon sequestration rate of vegetation and ecosystem was high in dolomite, moderate in limestone, and low in dolomitic sandstone. In Cupressus funebris plantation, the carbon sequestration rate was in the order of limestone>dolomite>dolomitic sandstone. These findings revealed that lithology is an important factor affecting ecosystem carbon pools, and plantation ecosystems have low biomass and low carbon density in karst areas.
Topics: Carbon Sequestration; Ecosystem; Forests; Calcium Carbonate; Carbon; Soil; Cupressaceae; Cinnamomum zeylanicum
PubMed: 36454917
DOI: 10.1371/journal.pone.0276537 -
Environmental Science & Technology Jun 2022The spectrophotometric methodology for carbonate ion determination in seawater was first published in 2008 and has been continuously evolving in terms of reagents and... (Review)
Review
The spectrophotometric methodology for carbonate ion determination in seawater was first published in 2008 and has been continuously evolving in terms of reagents and formulations. Although being fast, relatively simple, affordable, and potentially easy to implement in different platforms and facilities for discrete and autonomous observations, its use is not widespread in the ocean acidification community. This study uses a merged overdetermined CO system data set (carbonate ion, pH, and alkalinity) obtained from 2009 to 2020 to assess the differences among the five current approaches of the methodology through an internal consistency analysis and discussing the sources of uncertainty. Overall, the results show that none of the approaches meet the climate goal (± 1 % standard uncertainty) for ocean acidification studies for the whole carbonate ion content range in this study but usually fulfill the weather goal (± 10 % standard uncertainty). The inconsistencies observed among approaches compromise the consistency of data sets among regions and through time, highlighting the need for a validated standard operating procedure for spectrophotometric carbonate ion measurements as already available for the other measurable CO variables.
Topics: Calcium Carbonate; Carbon Dioxide; Carbonates; Hydrogen-Ion Concentration; Oceans and Seas; Seawater; Spectrophotometry
PubMed: 35670676
DOI: 10.1021/acs.est.1c06083 -
Journal of Applied Microbiology Feb 2018Growing industrialization and the desire for a better economy in countries has accelerated the emission of greenhouse gases (GHGs), by more than the buffering capacity... (Review)
Review
Growing industrialization and the desire for a better economy in countries has accelerated the emission of greenhouse gases (GHGs), by more than the buffering capacity of the earth's atmosphere. Among the various GHGs, carbon dioxide occupies the first position in the anthroposphere and has detrimental effects on the ecosystem. For decarbonization, several non-biological methods of carbon capture, utilization and storage (CCUS) have been in use for the past few decades, but they are suffering from narrow applicability. Recently, CO emission and its disposal related problems have encouraged the implementation of bioprocessing to achieve a zero waste economy for a sustainable environment. Microbial carbonic anhydrase (CA) catalyses reversible CO hydration and forms metal carbonates that mimic the natural phenomenon of weathering/carbonation and is gaining merit for CCUS. Thus, the diversity and specificity of CAs from different micro-organisms could be explored for CCUS. In the literature, more than 50 different microbial CAs have been explored for mineral carbonation. Further, microbial CAs can be engineered for the mineral carbonation process to develop new technology. CA driven carbonation is encouraging due to its large storage capacity and favourable chemistry, allowing site-specific sequestration and reusable product formation for other industries. Moreover, carbonation based CCUS holds five-fold more sequestration capacity over the next 100 years. Thus, it is an eco-friendly, feasible, viable option and believed to be the impending technology for CCUS. Here, we attempt to examine the distribution of various types of microbial CAs with their potential applications and future direction for carbon capture. Although there are few key challenges in bio-based technology, they need to be addressed in order to commercialize the technology.
Topics: Bacteria; Bacterial Proteins; Biotechnology; Carbon; Carbon Dioxide; Carbonic Anhydrases; Prospective Studies
PubMed: 28921830
DOI: 10.1111/jam.13589 -
Geobiology Sep 2022Marine and lacustrine carbonate minerals preserve carbon cycle information, and their stable carbon isotope values (δ C) are frequently used to infer and reconstruct...
Marine and lacustrine carbonate minerals preserve carbon cycle information, and their stable carbon isotope values (δ C) are frequently used to infer and reconstruct paleoenvironmental changes. However, multiple processes can influence the δ C values of bulk carbonates, confounding the interpretation of these values in terms of conditions at the time of mineral precipitation. Co-existing carbonate forms may represent different environmental conditions, yet few studies have analyzed δ C values of syndepositional carbonate grains of varying morphologies to investigate their origins. Here, we combine stable isotope analyses, metagenomics, and geochemical modeling to interpret δ C values of syndepositional carbonate spherules (>500 μm) and fine-grained micrite (<63 μm) from a ~1600-year-long sediment record of a hypersaline lake located on the coral atoll of Kiritimati, Republic of Kiribati (1.9°N, 157.4°W). Petrographic, mineralogic, and stable isotope results suggest that both carbonate fractions precipitate in situ with minor diagenetic alterations. The δ C values of spherules are high compared to the syndepositional micrite and cannot be explained by mineral differences or external perturbations, suggesting a role for local biological processes. We use geochemical modeling to test the hypothesis that the spherules form in the surface microbial mat during peak diurnal photosynthesis when the δ C value of dissolved inorganic carbon is elevated. In contrast, we hypothesize that the micrite may precipitate more continuously in the water as well as in sub-surface, heterotrophic layers of the microbial mat. Both metagenome and geochemical model results support a critical role for photosynthesis in influencing carbonate δ C values. The down-core spherule-micrite offset in δ C values also aligns with total organic carbon values, suggesting that the difference in the δ C values of spherules and micrite may be a more robust, inorganic indicator of variability in productivity and local biological processes through time than the δ C values of individual carbonate forms.
Topics: Carbon; Carbon Isotopes; Carbonates; Lakes; Photosynthesis
PubMed: 35851522
DOI: 10.1111/gbi.12509 -
BMC Plant Biology May 2022Karst habitats are uniquely characterized by high bicarbonate, high nitrate, and low ammonium, which are in-conducive to their growth and biodiversity. The occurrence of...
Karst habitats are uniquely characterized by high bicarbonate, high nitrate, and low ammonium, which are in-conducive to their growth and biodiversity. The occurrence of inorganic carbon and nitrogen in karst soil profoundly affects the carbon/nitrogen metabolism and adaptability of plants. However, there has been no final conclusion to the joint interactions of carbon and nitrogen metabolism in plants under karst habitats. In this study, we selected a karst-adaptable plant Orychophragmus violaceus (Ov), and a non-karst-adaptable plant Brassica napus (Bn) as experimental plants, and compared their joint effects of carbon and nitrogen metabolism under simulated karst habitats. It was found that the two species had different joint effects of carbon and nitrogen metabolisms. Bicarbonate and nitrate joint promoted photosynthetic activity and glucose metabolism, facilitating the carbon/nitrogen metabolism and growth of Ov, but their impacts on the carbon and nitrogen metabolism were insignificant in Bn. Bicarbonate and ammonium joint inhibited the photosynthesis and nitrogen metabolism, but promoted water use efficiency in Ov, leading to its enhance of growth reduction, ammonium toxicity alleviation, and drought resistance, while they inhibited the water use efficiency of Bn. In general, bicarbonate and nitrate/ammonium more significantly joint affected the carbon and nitrogen metabolism in Ov than Bn, which is vital for Ov to adapt to karst habitats.
Topics: Ammonium Compounds; Bicarbonates; Brassica napus; Carbon; Ecosystem; Nitrates; Nitrogen; Organic Chemicals; Water
PubMed: 35619072
DOI: 10.1186/s12870-022-03646-1 -
Geobiology Jan 2023The record of life during the Proterozoic is preserved by several different lithologies, but two in particular are linked both spatially and temporally: chert and... (Review)
Review
The record of life during the Proterozoic is preserved by several different lithologies, but two in particular are linked both spatially and temporally: chert and carbonate. These lithologies capture a snapshot of dominantly peritidal environments during the Proterozoic. Early diagenetic chert preserves some of the most exceptional Proterozoic biosignatures in the form of microbial body fossils and mat textures. This fossiliferous and kerogenous chert formed in shallow marine environments, where chert nodules, layers, and lenses are often surrounded by and encased within carbonate deposits that themselves often contain kerogen and evidence of former microbial mats. Here, we review the record of biosignatures preserved in peritidal Proterozoic chert and chert-hosting carbonate and discuss this record in the context of experimental and environmental studies that have begun to shed light on the roles that microbes and organic compounds may have played in the formation of these deposits. Insights gained from these studies suggest temporal trends in microbial-environmental interactions and place new constraints on past environmental conditions, such as the concentration of silica in Proterozoic seawater, interactions among organic compounds and cations in seawater, and the influence of microbial physiology and biochemistry on selective preservation by silicification.
Topics: Geologic Sediments; Fossils; Carbonates; Seawater; Silicon Dioxide
PubMed: 36268586
DOI: 10.1111/gbi.12527