Biogeosciences最新文献

{"title":"Photochemistry of the sea-surface microlayer (SML) influenced by a phytoplankton bloom: a mesocosm study","authors":"Olenka Jibaja Valderrama, Daniele Scheres Firak, Thomas Schaefer, Manuela van Pinxteren, Khanneh Wadinga Fomba, Hartmut Herrmann","doi":"10.5194/bg-23-1965-2026","DOIUrl":"https://doi.org/10.5194/bg-23-1965-2026","url":null,"abstract":"Abstract. The sea-surface microlayer (SML) is the thin boundary interface between the ocean and the atmosphere, and it is expected to play a crucial role in atmospheric chemistry on a global scale. Being a biologically-enriched environment exposed to strong actinic radiation, the SML is potentially a hotspot for photochemical reactions that have relevance in the transformation and cycling of organic compounds. The present study explores the photochemical production and degradation of carbonyl compounds, as well as the photochemical oxidation capacity in both ambient SML and underlying water (ULW) samples. Natural seawater samples were collected during a mesocosm study where a phytoplankton bloom was induced through the controlled addition of inorganic nutrients. To assess the photochemistry of carbonyl compounds, collected SML and ULW samples were irradiated for 5 h. The photochemical formation and degradation of 17 carbonyl compounds were quantified by monitoring compound-specific changes in concentrations, which varied significantly across the samples. Before irradiation, values in the SML ranged from 201–762 nmol L−1 in the pre-bloom phase, 984–4591 nmol L−1 in the bloom phase, and 647–4894 nmol L−1 in the post-bloom phase; while in the ULW they were significantly lower (e.g., 136–366 nmol L−1 in the bloom phase). After 5 h of irradiation, the concentrations of carbonyl compounds increased further, reaching up to 6026 nmol L−1 in the SML during the bloom phase and 419 nmol L−1 in the ULW. Experimental evidence suggests an enhanced photochemical activity in the SML during the bloom phase for glyoxal, methylglyoxal, methyl vinyl ketone (MVK), methacrolein, acrolein, crotonaldehyde, heptanal, biacetyl, hexanal and trans-2-hexenal. The observed photooxidation capacity of the seawater samples indicate a dominant influence of redox active species like metal ions, rather than of the phytoplankton bloom phases. The overall photochemical oxidation capacity was similar for both SML and ULW samples, with average values of 34 µM s−1. Our findings show an influence of biological activity in the photochemistry of carbonyl compounds in the SML and its implications for the emission of volatile organic compounds (VOCs) to the marine atmosphere, pointing to the complex interaction of biotic and abiotic factors in the air–sea boundary and underscoring the relevance of marine photochemistry in biogeochemical processes.","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"23 5","pages":"1965-1985"},"PeriodicalIF":0.0,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://bg.copernicus.org/articles/23/1965/2026/bg-23-1965-2026.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147895234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of basalt, concrete fines, and steel slag on maize growth and toxic trace element accumulation in an enhanced weathering experiment","authors":"Jet Rijnders, Arthur Vienne, Sara Vicca","doi":"10.5194/bg-22-2803-2025","DOIUrl":"https://doi.org/10.5194/bg-22-2803-2025","url":null,"abstract":"Abstract. Terrestrial enhanced silicate weathering is a CO2 removal technology involving the application of ground silicate materials to agricultural soils. Next to its CO2 removal potential, it can improve soil fertility and crop growth, but silicate materials can also contain toxic trace elements. In a mesocosm experiment, we investigated the effect of basalt, concrete fines, and steel slag on biomass, nutrients, and the toxic trace element concentration of Zea mays, using a dose–response approach. Plant biomass increased with basalt but not with concrete fines or steel slag. Generally, plant Ca, Mg, and corn Si concentrations increased with an increasing silicate application amount as a result of increased availability to plants. In contrast, plant N, P, and K concentrations were hardly affected by silicate application. Besides increased leaf Pb concentrations with steel slag application, which did not exceed the maximum limit set by the World Health Organization (WHO) and Food and Agriculture Organization (FAO) (0.05 mg Pb kg−1 ww, where “ww” denotes wet weight), the toxic trace element concentrations in aerial plant tissues mostly decreased with increasing silicate application amount, presumably because of an increased soil pH and accumulation in plant roots. Thus, our study indicates mixed effects of silicate application on maize while also suggesting that the risk of toxic trace element contamination after a one-time application of the tested silicates is limited.","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"22 12","pages":"2803-2829"},"PeriodicalIF":0.0,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://bg.copernicus.org/articles/22/2803/2025/bg-22-2803-2025.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147880175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial and seasonal variability in volatile organic sulfur compounds in seawater and the overlying atmosphere of the Bohai and Yellow seas","authors":"Juan Yu, Lei Yu, Zhen He, Gui-Peng Yang, Jing‐Guang Lai, Qian Liu","doi":"10.5194/bg-21-161-2024","DOIUrl":"https://doi.org/10.5194/bg-21-161-2024","url":null,"abstract":"Abstract. Volatile organic sulfur compounds (VSCs), including carbon disulfide (CS2), dimethyl sulfide (DMS), and carbonyl sulfide (COS), were surveyed in the seawater of the Bohai and Yellow seas and the overlying atmosphere during spring and summer of 2018 to understand the production and loss of VSCs and their influence factors. The concentration ranges of COS, DMS, and CS2 in the surface seawater were 0.14–0.42, 0.41–7.74, and 0.01–0.18 nmol L−1 during spring and 0.32–0.61, 1.31–18.12, and 0.01–0.65 nmol L−1 during summer, respectively. The COS concentrations exhibited positive correlation with dissolved organic carbon (DOC) concentrations in seawater during summer, which verified the photochemical production of COS from chromophoric dissolved organic matter (CDOM). High DMS concentrations occurred near the Yellow River, Laizhou Bay, and Yangtze River estuary, coinciding with high nitrate and chlorophyll (Chl) a concentrations due to river discharge during summer. The COS, DMS, and CS2 concentrations were the highest in the surface seawater and decreased with the depth. The mixing ratios of COS, DMS, and CS2 in the atmosphere were 255.9–620.2, 1.3–191.2, and 5.2–698.8 pptv during spring and 394.6–850.1, 10.3–464.3, and 15.3–672.7 pptv in summer, respectively. The ratios of mean oceanic concentrations and atmospheric mixing ratios for summer to spring in COS, DMS, and CS2 were 1.8, 3.1, 3.7 and 1.6, 4.6, 1.5, respectively. The ratios of the mean sea-to-air fluxes for summer to spring in COS, DMS, and CS2 were 1.2, 2.1, and 4.3. The sea-to-air fluxes of VSCs indicated that the marginal seas are important sources of VSCs in the atmosphere. The results support a better understanding of the contribution of VSCs in marginal seas.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"35 48","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139442808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Root distributions predict shrub–steppe responses to precipitation intensity","authors":"A. Kulmatiski, Martin C. Holdrege, Cristina Chirvasă, Karen H. Beard","doi":"10.5194/bg-21-131-2024","DOIUrl":"https://doi.org/10.5194/bg-21-131-2024","url":null,"abstract":"Abstract. Precipitation events are becoming more intense around the world, changing the way water moves through soils and plants. Plant rooting strategies that sustain water uptake under these conditions are likely to become more abundant (e.g., shrub encroachment). Yet, it remains difficult to predict species responses to climate change because we typically do not know where active roots are located or how much water they absorb. Here, we applied a water tracer experiment to describe forb, grass, and shrub root distributions. These measurements were made in 8 m by 8 m field shelters with low or high precipitation intensity. We used tracer uptake data in a soil water flow model to estimate how much water respective plant root tissues absorb over time. In low-precipitation-intensity plots, deep shrub roots were estimated to absorb the most water (93 mm yr−1) and shrubs had the greatest aboveground cover (27 %). Grass root distributions were estimated to absorb an intermediate amount of water (80 mm yr−1) and grasses had intermediate aboveground cover (18 %). Forb root distributions were estimated to absorb the least water (79 mm yr−1) and had the least aboveground cover (12 %). In high-precipitation-intensity plots, shrub and forb root distributions changed in ways that increased their water uptake relative to grasses, predicting the increased aboveground growth of shrubs and forbs in these plots. In short, water uptake caused by different rooting distributions predicted plant aboveground cover. Our results suggest that detailed descriptions of active plant root distributions can predict plant growth responses to climate change in arid and semi-arid ecosystems.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"46 26","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139448233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geographically divergent trends in snow disappearance timing and fire ignitions across boreal North America","authors":"Thomas D. Hessilt, B. Rogers, R. Scholten, S. Potter, Thomas A. J. Janssen, S. Veraverbeke","doi":"10.5194/bg-21-109-2024","DOIUrl":"https://doi.org/10.5194/bg-21-109-2024","url":null,"abstract":"Abstract. The snow cover extent across the Northern Hemisphere has diminished, while the number of lightning ignitions and amount of burned area have increased over the last 5 decades with accelerated warming. However, the effects of earlier snow disappearance on fire are largely unknown. Here, we assessed the influence of snow disappearance timing on fire ignitions across 16 ecoregions of boreal North America. We found spatially divergent trends in earlier (later) snow disappearance, which led to an increasing (decreasing) number of ignitions for the northwestern (southeastern) ecoregions between 1980 and 2019. Similar northwest–southeast divergent trends were observed in the changing length of the snow-free season and correspondingly the fire season length. We observed increases (decreases) over northwestern (southeastern) boreal North America which coincided with a continental dipole in air temperature changes between 2001 and 2019. Earlier snow disappearance induced earlier ignitions of between 0.22 and 1.43 d earlier per day of earlier snow disappearance in all ecoregions between 2001 and 2019. Early-season ignitions (defined by the 20 % earliest fire ignitions per year) developed into significantly larger fires in 8 out of 16 ecoregions, being on average 77 % larger across the whole domain. Using a piecewise structural equation model, we found that earlier snow disappearance is a good direct proxy for earlier ignitions but may also result in a cascade of effects from earlier desiccation of fuels and favorable weather conditions that lead to earlier ignitions. This indicates that snow disappearance timing is an important trigger of land–atmosphere dynamics. Future warming and consequent changes in snow disappearance timing may contribute to further increases in western boreal fires, while it remains unclear how the number and timing of fire ignitions in eastern boreal North America may change with climate change.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"14 5","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Origin and role of non-skeletal carbonate in coralligenous build-ups: new geobiological perspectives in biomineralization processes","authors":"Mara Cipriani, C. Apollaro, Daniela Basso, Pietro Bazzicalupo, Marco Bertolino, V. Bracchi, Fabio Bruno, Gabriele Costa, R. Dominici, A. Gallo, M. Muzzupappa, A. Rosso, R. Sanfilippo, F. Sciuto, G. Vespasiano, Adriano Guido","doi":"10.5194/bg-21-49-2024","DOIUrl":"https://doi.org/10.5194/bg-21-49-2024","url":null,"abstract":"Abstract. The coralligenous build-ups located on the Mediterranean shelf in front of Marzamemi (SE Sicily, Italy) represent useful natural examples to use in studying the relationship between skeletal organisms and non-skeletal components in marine bioconstructions. Coralligenous build-ups are formed in open marine systems, and their comparison with coeval bioconstructions (biostalactites) of confined environments, like submarine caves, allows depicting the complex interactions between metazoans and microbial communities in the formations of recent bioconstructions in different Mediterranean settings. In this study, two coralligenous build-ups were characterized in terms of organisms and sediments involved in their formation. The framework mainly consists of coralline algae and subordinate bryozoans and serpulids. Sponges affect the general morphology of the bioconstructions both interacting with skeletonized organisms and through bioerosion activity. The micrite or microcrystalline calcite is present in minor amounts compared to other components that form the build-ups and consists of two types: autochthonous (in situ) and allochthonous (detrital). Fine autochthonous micrite mineralized directly inside the framework cavities and shows aphanitic or peloidal fabric, produced by organomineralization processes of soft sponge tissues and microbial metabolic activity, respectively. The detrital micrite occurring inside cavities derives from external sources or erosion processes of the bioconstructions themselves. This component has been classified as organic or inorganic based on the organic matter contents deduced by UV epifluorescence. A great quantity of sponges live in cavities of the coralligenous build-ups and compete with carbonatogenic bacteria for the same cryptic spaces, limiting the production of microbialites. The sharing of a similar relationship between sponges and microbial communities by coralligenous concretion and biotic crusts of particular submarine caves suggests that this competition is not habitat-specific. On the contrary, it may develop in a range of environmental settings, from open to cryptic systems, and could be used to clarify the role of metazoans vs. microbialites in palaeoecological reconstructions.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"12 4","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139451588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Driving and limiting factors of CH4 and CO2 emissions from coastal brackish-water wetlands in temperate regions","authors":"Emilia Chiapponi, S. Silvestri, Denis Zannoni, M. Antonellini, B. Giambastiani","doi":"10.5194/bg-21-73-2024","DOIUrl":"https://doi.org/10.5194/bg-21-73-2024","url":null,"abstract":"Abstract. Coastal wetlands play a fundamental role in mitigating climate change thanks to their ability to store large amounts of organic carbon in the soil. However, degraded freshwater wetlands are also known to be the first natural emitter of methane (CH4). Salinity is known to inhibit CH4 production, but its effect in brackish ecosystems is still poorly understood. This study provides a contribution to understanding how environmental variables may affect greenhouse gas (GHG) emissions in coastal temperate wetlands. We present the results of over 1 year of measurements performed in four wetlands located along a salinity gradient on the northeast Adriatic coast near Ravenna, Italy. Soil properties were determined by coring soil samples, while carbon dioxide (CO2) and CH4 fluxes from soils and standing waters were monitored monthly by a portable gas flux meter. Additionally, water levels and surface and groundwater physical–chemical parameters (temperature, pH, electrical conductivity, and sulfate concentrations of water) were monitored monthly by multiparametric probes. We observed a substantial reduction in CH4 emissions when water depth exceeded the critical threshold of 50 cm. Regardless of the water salinity value, the mean CH4 flux was 5.04 gm-2d-1 in freshwater systems and 12.27 gm-2d-1 in brackish ones. In contrast, when water depth was shallower than 50 cm, CH4 fluxes reached an average of 196.98 gm-2d-1 in freshwater systems, while non-significant results are available for brackish/saline waters. Results obtained for CO2 fluxes showed the same behavior described for CH4 fluxes, even though they were statistically non-significant. Temperature and irradiance strongly influenced CH4 emissions from water and soil, resulting in higher rates during summer and spring.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"106 25","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139387913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporary stratification promotes large greenhouse gas emissions in a shallow eutrophic lake","authors":"Thomas A. Davidson, Martin Søndergaard, J. Audet, E. Levi, Chiara Esposito, Tuba Bucak, Anders Nielsen","doi":"10.5194/bg-21-93-2024","DOIUrl":"https://doi.org/10.5194/bg-21-93-2024","url":null,"abstract":"Abstract. Shallow lakes and ponds undergo frequent temporary thermal stratification. How this affects greenhouse gas (GHG) emissions is moot, with both increased and reduced GHG emissions hypothesised. Here, weekly estimations of GHG emissions, over the growing season from May to September, were combined with temperature and oxygen profiles of an 11 ha temperate shallow lake to investigate how thermal stratification shapes GHG emissions. There were three main stratification periods with profound anoxia occurring in the bottom waters upon isolation from the atmosphere. Average diffusive emissions of methane (CH4) and nitrous oxide (N2O) were larger and more variable in the stratified phase, whereas carbon dioxide (CO2) was on average lower, though these differences were not statistically significant. In contrast, there was a significant order of magnitude increase in CH4 ebullition in the stratified phase. Furthermore, at the end of the period of stratification, there was a large efflux of CH4 and CO2 as the lake mixed. Two relatively isolated turnover events were estimated to have released the majority of the CH4 emitted between May and September. These results demonstrate how stratification patterns can shape GHG emissions and highlight the role of turnover emissions and the need for high-frequency measurements of GHG emissions, which are required to accurately characterise emissions, particularly from temporarily stratifying lakes.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"11 10","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139388959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil priming effects and involved microbial community along salt gradients","authors":"Haoli Zhang, Doudou Chang, Zhifeng Zhu, Chunmei Meng, Kaiyong Wang","doi":"10.5194/bg-21-1-2024","DOIUrl":"https://doi.org/10.5194/bg-21-1-2024","url":null,"abstract":"Abstract. Soil salinity mediates microorganisms and soil processes, like soil organic carbon (SOC) cycling. Yet, how soil salinity affects SOC mineralization via shaping bacterial community diversity and composition remains elusive. Therefore, soils were sampled along a salt gradient (salinity at 0.25 %, 0.58 %, 0.75 %, 1.00 %, and 2.64 %) and incubated for 90 d to investigate (i) SOC mineralization (i.e., soil priming effects induced by cottonseed meal, as substrate) and (ii) the responsible bacteria community by using high-throughput sequencing and natural abundance of 13C isotopes (to partition cottonseed-meal-derived CO2 and soil-derived CO2). We observed a negative priming effect during the first 28 d of incubation that turned to a positive priming effect after day 56. Negative priming at the early stage might be due to the preferential utilization of cottonseed meal. The followed positive priming decreased with the increase in salinity, which might be caused by the decreased α diversity of microbial communities in soil with high salinity. Specifically, soil pH and electrical conductivity (EC) along the salinity gradient were the dominant variables modulating the structure of the microbial community and consequently SOC priming (estimated by distance-based multivariate analysis and path analysis). By adopting two-way orthogonal projections to latent structures (O2PLS), priming effects were linked with specific microbial taxa; e.g., Proteobacteria (Luteimonas, Hoeflea, and Stenotrophomonas) were the core microbial genera that were attributed to the substrate-induced priming effects. Here, we highlight that the increase in salinity reduced the diversity of the microbial community and shifted dominant microorganisms (Actinobacteria and Proteobacteria: Luteimonas, Hoeflea, and Stenotrophomonas) that determined SOC priming effects, which provides a theoretical basis for understanding SOC dynamics and microbial drivers under the salinity gradient.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"123 3","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139390769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reviews and syntheses: expanding the global coverage of gross primary production and net community production measurements using Biogeochemical-Argo floats","authors":"Robert W. Izett, K. Fennel, A. Stoer, D. Nicholson","doi":"10.5194/bg-21-13-2024","DOIUrl":"https://doi.org/10.5194/bg-21-13-2024","url":null,"abstract":"Abstract. This paper provides an overview and demonstration of emerging float-based methods for quantifying gross primary production (GPP) and net community production (NCP) using Biogeochemical-Argo (BGC-Argo) float data. Recent publications have described GPP methods that are based on the detection of diurnal oscillations in upper-ocean oxygen or particulate organic carbon concentrations using single profilers or a composite of BGC-Argo floats. NCP methods rely on budget calculations to partition observed tracer variations into physical or biological processes occurring over timescales greater than 1 d. Presently, multi-year NCP time series are feasible at near-weekly resolution, using consecutive or simultaneous float deployments at local scales. Results, however, are sensitive to the choice of tracer used in the budget calculations and uncertainties in the budget parameterizations employed across different NCP approaches. Decadal, basin-wide GPP calculations are currently achievable using data compiled from the entire BGC-Argo array, but finer spatial and temporal resolution requires more float deployments to construct diurnal tracer curves. A projected, global BGC-Argo array of 1000 floats should be sufficient to attain annual GPP estimates at 10∘ latitudinal resolution if floats profile at off-integer intervals (e.g., 5.2 or 10.2 d). Addressing the current limitations of float-based methods should enable enhanced spatial and temporal coverage of marine GPP and NCP measurements, facilitating global-scale determinations of the carbon export potential, training of satellite primary production algorithms, and evaluations of biogeochemical numerical models. This paper aims to facilitate broader uptake of float GPP and NCP methods, as singular or combined tools, by the oceanographic community and to promote their continued development.\u0000","PeriodicalId":8899,"journal":{"name":"Biogeosciences","volume":"14 7","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139452237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}