Progress in Oceanography最新文献

{"title":"Drivers of microbial carbon biomass variability in two oceanic regions of the Gulf of Mexico","authors":"","doi":"10.1016/j.pocean.2024.103348","DOIUrl":"10.1016/j.pocean.2024.103348","url":null,"abstract":"<div><p>The microbial plankton community is an integral part of the pelagic ecosystem. It hosts essential functional groups that play a vital role in organic carbon production, release, uptake, and degradation within open-ocean ecosystems. Given its significance, carbon biomass estimates are urgently needed, especially in oligotrophic regions, to provide and enhance our knowledge of biogenic carbon pools. They also aid in validating biogeochemical models that characterize the functioning of these extensive marine ecosystems within the global carbon cycle. This study addresses the temporal variability of microbial community biomass in two oceanic zones: the west-central (Perdido) and southern (Coatzacoalcos) areas of the Gulf of Mexico. During three seasonally contrasting periods (<em>nortes</em>, <em>rainy</em>, and <em>dry</em> seasons), seawater samples were collected from the euphotic zone in both regions to estimate the carbon biomass of different pico- (&lt;2–3 µm), nano-, and microplankton groups (&gt;3–200 µm). Carbon biomass assessments for the microbial groups were based on their abundance and carbon conversion factors. Overall, we found a significant contribution of pico-prokaryotic components (heterotrophic bacteria, <em>Prochloroccocus</em>, and <em>Synechoccocus</em>) to the total microbial carbon stock of the euphotic zone (84–89 % global estimates). The finding suggests these microorganisms are key functional groups that drive carbon production and fate in the Gulf of Mexico ecosystem. Pico-cyanobacteria, especially <em>Prochloroccocus</em>, were the dominant primary producers (68–82 % total autotrophic carbon), mainly in the upper layer of the oligotrophic euphotic zone. This vertical pattern implies that the deep chlorophyll-<em>a</em> maximum (DCM) depth level was unrelated to a net increase in phytoplankton biomass in the three study periods. The distribution of microbial carbon biomass exhibited striking differences associated with winter mixing (the <em>nortes</em> season), high river discharge accompanied by cross-shelf transport (the <em>rainy</em> season), and the dynamics of mesoscale structures. Ecological aspects, such as the habitat preference of the organisms and the seasonal complementary development of mixotrophic and heterotrophic grazers and their prey, were also essential drivers in regulating the microbial carbon pool of both oceanic regions. The microbial carbon assessments conducted in this study contribute to identifying and quantifying key planktonic functional groups involved in the biogeochemical carbon cycle in the Gulf of Mexico open-ocean ecosystem.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142274555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nutrient stoichiometry drives the phytoplankton populations during the progression of upwelling along the eastern Arabian Sea","authors":"","doi":"10.1016/j.pocean.2024.103347","DOIUrl":"10.1016/j.pocean.2024.103347","url":null,"abstract":"<div><p>The basin-wide phytoplankton succession and community behaviour in response to varying nutrient patterns during various upwelling phases are detailed, for the first time, in the eastern Arabian Sea (EAS, ∼6^◦ to 22^◦N) during the summer monsoon (SM) of 2018. Three consecutive observations were carried out during early SM (June-July), peak SM (August), and late SM (September-October), representing different phases of upwelling. During the early phase of upwelling, high phytoplankton biomass was observed in the south (column-integrated chlorophyll <em>a</em>: 74.09 ± 60.05 mg m⁻²) and moderate levels in the central (25.75 ± 6.51 mg m⁻²) and north (30.31 ± 12.32 mg m⁻²) EAS coastal waters. Diatoms were the dominant group (60–90 %) in the coastal stations throughout the upwelling period. Offshore regions characterised by deeper nutriclines (&gt;50 m) had pico-phytoplankton dominance, including cyanobacteria (14–30 %), chlorophytes (19–24 %) and prochlorophytes (12–15 %); however, due to low nitrogen to phosphorous ratio (N/P: 2.6 ± 1.31) during this period, the contribution of diatoms decreased to less than 20 % in the offshore waters compared to the coastal EAS. During peak SM, upwelling induced shoaling of nutriclines and high N/P conditions (8.4 ± 5.25) in the mixed layers of south EAS coastal waters substantially enhanced phytoplankton biomass (chlorophyll <em>a</em>: 129.06 ± 96.24 mg m⁻²). Additionally, the shallow nutriclines supported diatoms dominance in offshore waters, particularly in the central EAS (up to 65 %), relative to the south and north EAS (22 to 33 %), where the upwelling intensity was weaker. The withdrawal of upwelling led to a deepening of nutricline and low N/P conditions (3.33 ± 2.77 in coastal and 3.35 ± 2.26 in offshore waters) during late SM. This supported the occurrence of cyanobacteria and dinoflagellates, as the contribution of diatoms to the total phytoplankton community sharply decreased to 50 %. In other words, upwelling in the EAS brings nitrogen-deficient (denitrified) waters; the available nitrogen is immediately consumed by the diatom community, resulting in low N/P conditions that favour the dominance of the cyanobacterial population towards late SM. Overall, substantial intra-seasonal variability was observed in nutrient stoichiometry, strongly modulated by the intensity of physical processes affecting the phytoplankton populations. Continuous monitoring is required to understand the phytoplankton populations, their impact on higher trophic levels, and the overall health of aquatic food web structure in the EAS.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental variability shapes trophic and resource partitioning between epipelagic and mesopelagic biomes in oceanic provinces: Implications in a globally changing ocean","authors":"","doi":"10.1016/j.pocean.2024.103339","DOIUrl":"10.1016/j.pocean.2024.103339","url":null,"abstract":"<div><p>Trophic links between the epipelagic (&lt; 200 m) and mesopelagic layers of the Indian Ocean were investigated by carbon and nitrogen stable isotope ratios of 2405 samples collected from 2002 to 2016, and that encompass the base of trophic webs, and primary, secondary and tertiary consumers. The samples include particulate organic matter, gastropods, gelatinous organisms such as salps and pyrosomes, crustaceans, mesopelagic fishes, micronektonic and nektonic squids, tuna and swordfish. Stable δ¹³C and δ¹⁵N values were used to investigate trophic and resource partitioning between epipelagic <em>vs</em> mesopelagic (migrators and non-migrators), feeding patterns (zooplanktivorous <em>vs</em> micronektivorous), and at seamounts and off-seamount locations. We also investigated how contrasting environmental conditions within two biogeochemical provinces, the ISSG (Indian South Subtropical Gyre) and EAFR (East African Coastal Province), influenced stable isotope patterns. Our data suggest that broad-scale biogeochemical differences and local environmental conditions significantly shape trophic and resource partitioning. In oligotrophic systems, epipelagic migrating and non epipelagic-migrating organisms rely on food webs where suspended particles are ¹⁵N-enriched and organic matter recycled/re-processed. We show that seamounts form strong isotopic topographic barriers (which we define as “isobiome”) that impact the trophic linkages/connections between epipelagic migrants and non-epipelagic migrants, and those with zooplanktivorous feeding patterns. This study reveals that the trophic and resource partitioning in the ocean is more complex than initially thought, when environmental variability, bathymetric gradients, and a wider range of samples are taken into account compared to earlier studies. We also showed that a warmer ocean led to a reduction in productivity, lower values of δ¹³C and δ¹⁵N, and potential shifts in food web trophic structure that remain to be investigated further. Finally, we discuss how important it is to unravel this complexity on a global scale given the vulnerability of epipelagic and mesopelagic communities due to anthropogenic pressures in the Anthropocene.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142229234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ benthic community response to a phytodetritus pulse in the Cabo Verde Abyssal Basin (tropical NE Atlantic)","authors":"","doi":"10.1016/j.pocean.2024.103340","DOIUrl":"10.1016/j.pocean.2024.103340","url":null,"abstract":"<div><p>Ecosystem functioning, i.e. the transfer of material through a system, supports the ecosystem services deep-sea sediments provide, including carbon sequestration, nutrient regeneration, and climate regulation. To date, seven studies globally have researched <em>in situ</em> how various benthic groups contribute to organic matter degradation in abyssal sediments through stable isotope tracer experiments, of which only one in the Atlantic (at the Porcupine Abyssal Plain or PAP). To expand the limited knowledge base on abyssal ecosystem functioning, we performed <em>in situ</em> stable isotope experiments in the Cabo Verde Abyssal Basin (CVAB, tropical North-East Atlantic). The Cabo Verde marine region is an oceanographically interesting region with complex currents, resulting in strong gradients of productivity and unique ecological characteristics. We conducted 2-day <em>in situ</em> incubations with organic substrate (lyophilised diatom culture) labelled with ¹³C and ¹⁵N stable isotopes through five benthic lander deployments to 4,200 m in an area presumed mesotrophic. We assessed sediment community oxygen consumption (SCOC), dissolved inorganic carbon (DI¹³C) production, nutrient fluxes, and label incorporation into bacteria, large Foraminifera (&gt;300 μm), meiobenthos, and macrofauna. Results were specifically compared across the Atlantic basin to the eutrophic PAP for which all the same system components were reported (<span><span>Witte et al. 2003</span></span>). At CVAB, bacteria and meiobenthos dominated phytodetritus processing (91% and 8%, respectively), in contrast to PAP where macrofauna dominated (98%). Phytodetritus remineralisation was two to three times lower at CVAB compared to PAP, most likely due to the low abundance of fast responding macrofauna. However, overall phytodetritus processing efficiency at CVAB was four times greater compared to PAP. Our results support a mesotrophic regime at the CVAB lander site, and provide a unique first insight into ecosystem functioning of tropical (low-latitude) abyssal systems in the Atlantic Ocean. A better understanding of abyssal ecosystem functioning in various ocean regions, to which this study contributes, provides insight into main regulators of abyssal communities and thus may have implications for our understanding of abyssal systems under future climate scenarios.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0079661124001460/pdfft?md5=05eafde81c0c66ed00e5ceefe336e1f6&pid=1-s2.0-S0079661124001460-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Modelling the complete life cycle of an arctic copepod reveals complex trade-offs between concurrent life cycle strategies","authors":"","doi":"10.1016/j.pocean.2024.103333","DOIUrl":"10.1016/j.pocean.2024.103333","url":null,"abstract":"<div><div><em>Calanus hyperboreus</em> is a large-bodied, biomass dominant species that performs a crucial ecosystem energy transfer by converting the spring phytoplankton bloom into lipid reserves that fuel the higher trophic levels of the Gulf of St. Lawrence (GSL) pelagic ecosystem, including the critically endangered North Atlantic right whale (<em>Eubalena glacialis</em>). Given that the GSL, the southernmost core habitat of <em>C. hyperboreus</em>, is undergoing rapid warming, developing a population model allows us to synthesize existing knowledge of the species, and to examine the species response to environmental conditions. To simulate the multi-year life cycle in the northwest GSL, model equations are implemented for ingestion, assimilation, respiration, egg production, stage development, mortality, and vertical migration behaviors including dormancy entry and exit. The 1-D particle-based model predicts the evolution of individual stage, structural mass, lipid, age, sex, abundance, and egg production, as well as the seasonal evolution of the population structure in the northwest GSL. Individual lipid-based thresholds inform the timing of ontogenetic vertical migration. Life cycle targets defined from a literature review are used to guide model parameterization and assess its performance. The simulated population structure, phenology, and size at stage are generally consistent with observations. Under 10 years of repeat year forcing, the model simulates a quasi-stable overwintering population composed of late stages CIV, CV and CVI. Observations suggest that stage CIV is the first overwintering stage in the GSL, and point to the occurrence of iteroparous females. Using the model, the relative success of diverse dormancy and reproductive phenotypes are explored. Second reproduction females reproduce earlier in winter than first reproduction females, with implications for the ability of the new generation to match the spring bloom and accumulate sufficient lipid to overwinter as stage CIV. Without iteroparity, the time window of reproduction contracts and the population is reduced, underscoring the role of a flexible multi-year life cycle in population success.</div></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Stable isotope spatial patterns for the Southwest Atlantic Ocean towards polar waters","authors":"","doi":"10.1016/j.pocean.2024.103337","DOIUrl":"10.1016/j.pocean.2024.103337","url":null,"abstract":"<div><p>Mapping stable isotope gradients (isoscapes) has become a powerful tool to understand and forecast the status and variability of marine ecosystems at different levels of ecological organization. To differentiate five marine areas from the Southwest Atlantic Ocean towards oceanic and polar waters, a key foraging area for many marine consumers, we built isoscapes at different spatial scales using carbon (<em>δ</em>¹³C) and nitrogen (<em>δ</em>¹⁵N) isotope values of phytoplankton, zooplankton and particulate organic matter in sediment. We analyzed the isotopic variability between marine areas in relation with oceanographic parameters (e.g. temperature, salinity) and geographical sampling site data (e.g. latitude, longitude). We collected samples during 6 oceanographic surveys conducted in spring and autumn between 2014 and 2019 at the Beagle Channel, the Atlantic coast of Tierra del Fuego and Burdwood Bank. We included also published isotopic data of zooplankton from two other oceanic areas (the Polar Frontal Zone and Polar Antarctic Peninsula waters) to construct large-scale isoscapes. We found that the marine areas analyzed have substantially different <em>δ</em>¹³C and <em>δ</em>¹⁵N baselines; some differences exist between spring and autumn but the general pattern of isotopic variability remains similar. Combining different biological components and spatial scale analysis, isotopic variability was found to be related to variables such as seawater temperature, depth, chlorophyll and nutrients. The generated data will enhance the efficacy of isoscapes in long-term monitoring initiatives that documents alterations in attributes and features across marine expanses. This is particularly pertinent to areas under legal protection, such as the oceanic Marine Protected Areas (MPAs) established in Argentine waters.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142163257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal resource tracking and use of sea-ice foraging habitats by albatrosses and large petrels","authors":"Ewan D. Wakefield, Erin L. McClymont, Ana P.B. Carneiro, John P. Croxall, Jacob González-Solís, Hannah M.V. Granroth-Wilding, Lesley Thorne, Victoria Warwick-Evans, Andrew G. Wood, Jose C. Xavier, Richard A. Phillips","doi":"10.1016/j.pocean.2024.103334","DOIUrl":"https://doi.org/10.1016/j.pocean.2024.103334","url":null,"abstract":"The Antarctic seasonal sea-ice zone (SIZ) is one of the most extensive and dynamic habitats on Earth. In summer, increased insolation and ice melt cause primary production to peak, sustaining large populations of locally-breeding seabirds. Due to their hypermobility, large Procellariiformes, including albatrosses, breeding in the subantarctic also have the potential to access the SIZ and track macroscale resource waves over the Sothern Ocean but the extent to which they do this is poorly known. Here, we analysed the foraging movements of breeding albatrosses and large petrels (seven species, 1298 individuals) recorded using GPS loggers and satellite-transmitters to quantify their use of sea-ice habitats and test whether they tracked seasonal drivers of primary production. Foraging latitudes of white-chinned petrels and black-browed , grey-headed and wandering albatrosses varied sinusoidally over the breeding season, presumably in response to lagged effects of solar irradiance on primary production. Foraging latitudes of northern and southern giant petrels ( and ), and light-mantled albatrosses , exhibited no strong seasonal trend, but the latter two species spent ≥ 20 % of their time in the SIZ during incubation and post-brood, prior to or at the time of the spring ice breakup. Southern giant petrels travelled hundreds of km into the pack ice, encountering sea-ice concentrations up to 100 %, whereas light-mantled albatrosses remained almost exclusively in open water near the Marginal Ice Zone (MIZ). The remaining species spent up to 15 % of their time in the SIZ, typically from 5-7 weeks after breakup, and avoided the MIZ. This supports hypotheses that sea ice presents albatrosses but not giant petrels with physical barriers to flight or foraging, and that open-water-affiliated species use the SIZ only after primary production stimulated by ice melt transfers to intermediate trophic levels. Given that all seven species used the SIZ, it is likely that the phenology and demography of these and many other subantarctic-breeding seabirds are mechanistically linked to sea-ice dynamics. Declines in Antarctic sea ice predicted under climate change could therefore modulate and exacerbate the already unsustainable anthropogenic impacts being experienced by these populations.","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":4.1,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal variations in the contribution of zooplankton fecal pellets to the particulate organic carbon fluxes over the slopes of the Pacific Arctic region","authors":"","doi":"10.1016/j.pocean.2024.103335","DOIUrl":"10.1016/j.pocean.2024.103335","url":null,"abstract":"<div><p>As part of the Korea Arctic Mooring System (KAMS), sequential sediment traps were deployed at KAMS1 over the East Siberian Sea slope (∼115 and ∼335 m) and at KAMS2 over the Chukchi Sea slope (325 m) to collect sinking particles from August 2017 to August 2019. Fecal pellet carbon (FPC) fluxes and their contribution to the particulate organic carbon (POC) fluxes were measured to assess the role of zooplankton fecal pellets in the biological carbon pump at both sites. FPC fluxes increased at the onset of an under-ice bloom and peaked during the melt period at both sites in 2018. At KAMS1, a remarkable increase in FPC fluxes reflected the enhanced grazing of large copepods during the anomalously productive spring and summer of 2018, however their contributions to the POC fluxes mostly remained &lt;10%. At KAMS2, relatively low FPC fluxes during the under-ice bloom suggested the export of a larger proportion of pellets produced by small copepods. Sustained FPC fluxes from January to May 2018 at KAMS2 contributed up to 24% of the POC fluxes, possibly resulting from pellet production by overwintering copepods grazing on particles laterally transported into the region in the presence of ice. These results indicate that despite their limited contribution to the POC fluxes, FPC fluxes varied with food availability, zooplankton community structure, and hydrographic conditions over the East Siberian and Chukchi Sea slopes.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142058504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution patterns of micronektonic crustaceans (Decapoda, Euphausiacea, and Lophogastrida) in the tropical and subtropical Atlantic Ocean","authors":"","doi":"10.1016/j.pocean.2024.103331","DOIUrl":"10.1016/j.pocean.2024.103331","url":null,"abstract":"<div><p>Large pelagic crustaceans are a main component of the micronekton community in the deep-sea having an important role in the food webs and the biological carbon pump. However, they are scarcely studied in comparison to other groups such as mesopelagic fish. Here, we analyse day/night and bathymetric variability in taxonomic composition, abundance, and biomass across a latitudinal transect in the Atlantic Ocean from off Brazil (15°S) to the Canary Islands (25°N). A total of 95 species were identified belonging to 9 different families, of which Euphausiidae was the most abundant family and Acanthephyridae the family contributing the most to the total biomass. We found distinct assemblages associated with Atlantic ecoregions related to the environmental variables. Diel vertical migrations were detected along the entire transect, even crossing the oxygen minimum zone, likely due to the metabolic adaptations of these organisms.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S007966112400137X/pdfft?md5=5c1f10070cb2698b49432fbe6212178b&pid=1-s2.0-S007966112400137X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142012566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Mapping phenoregions and phytoplankton seasonality in Northeast Pacific marine coastal ecosystems via a satellite-based approach","authors":"","doi":"10.1016/j.pocean.2024.103336","DOIUrl":"10.1016/j.pocean.2024.103336","url":null,"abstract":"<div><p>Phytoplankton phenology describes yearly algal growth cycles and characterises the timing, duration, and magnitude of bloom occurrences. This study used satellite chlorophyll-a data from 1998 to 2020 and the Hierarchical Agglomerative Clustering method to define phenoregions based on phytoplankton phenology spatial patterns over the British Columbia and Southeast Alaska coastal oceans. The defined phenoregions were used to simplify the spatial complexity of the heterogenous study region and thus better describe phytoplankton seasonality across the target area. The cluster analysis allowed the delineation of four coherent regions: two coastal regions and northern and southern shelf/offshore regions. Results showed that each phenoregion had distinguishable phytoplankton phenological characteristics, likely due to different physical forcings acting in these areas. Moreover, the interannual variability of the spring bloom initiation was evaluated considering interactions between sea surface temperature (SST) anomalies and the El Niño Southern Oscillation Index (ENSO). Early spring blooms were associated with positive SST anomalies and El Niño conditions; conversely, average or late spring blooms occurred in years with negative SST anomalies and La Niña conditions, with the strongest relationship occurring in the southern shelf/offshore phenoregion. This study provided new insights into the regionalisation of the British Columbia and Southeast Alaska coastal oceans based on phytoplankton phenology patterns. Given the critical role of phytoplankton as the base of the marine food web, such phenoregions have implications for regional zooplankton biomass and fish production. The link between phytoplankton phenology and climate drivers points to the importance of environmental change in phytoplankton bloom dynamics. Further research into the connection between phytoplankton bloom indices and zooplankton community structure and production would be an important step towards using these indices for ecosystem monitoring and fisheries management.</p></div>","PeriodicalId":20620,"journal":{"name":"Progress in Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0079661124001423/pdfft?md5=7aa2d9585c327fc795ef3d785b341fea&pid=1-s2.0-S0079661124001423-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142043673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}