1
|
Miettinen TP, Gomez AL, Wu Y, Wu W, Usherwood TR, Hwang Y, Roller BRK, Polz MF, Manalis SR. Cell size, density, and nutrient dependency of unicellular algal gravitational sinking velocities. SCIENCE ADVANCES 2024; 10:eadn8356. [PMID: 38968348 PMCID: PMC11225777 DOI: 10.1126/sciadv.adn8356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 06/04/2024] [Indexed: 07/07/2024]
Abstract
Eukaryotic phytoplankton, also known as algae, form the basis of marine food webs and drive marine carbon sequestration. Algae must regulate their motility and gravitational sinking to balance access to light at the surface and nutrients in deeper layers. However, the regulation of gravitational sinking remains largely unknown, especially in motile species. Here, we quantify gravitational sinking velocities according to Stokes' law in diverse clades of unicellular marine microalgae to reveal the cell size, density, and nutrient dependency of sinking velocities. We identify a motile algal species, Tetraselmis sp., that sinks faster when starved due to a photosynthesis-driven accumulation of carbohydrates and a loss of intracellular water, both of which increase cell density. Moreover, the regulation of cell sinking velocities is connected to proliferation and can respond to multiple nutrients. Overall, our work elucidates how cell size and density respond to environmental conditions to drive the vertical migration of motile algae.
Collapse
Affiliation(s)
- Teemu P. Miettinen
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Annika L. Gomez
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Yanqi Wu
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Weida Wu
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Thomas R. Usherwood
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Harvard-MIT Department of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Yejin Hwang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Benjamin R. K. Roller
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, 1030, Austria
| | - Martin F. Polz
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, 1030, Austria
| | - Scott R. Manalis
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| |
Collapse
|
2
|
Wang C, Liu F. Influence of oceanic mesoscale eddies on the deep chlorophyll maxima. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170510. [PMID: 38286277 DOI: 10.1016/j.scitotenv.2024.170510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 01/14/2024] [Accepted: 01/26/2024] [Indexed: 01/31/2024]
Abstract
The deployment of the biogeochemical Argo network significantly enhances our understanding of the ecological effects of mesoscale eddies at different ocean depths. In this study, satellite data and more than one hundred thousand biogeochemical Argo float profiles were used to analyze the responses of the deep chlorophyll maximum (DCM) to mesoscale eddies. The DCM profiles were categorized into two types: DAM (adaptation maximum) and DBM (biomass maximum), based on their adaptation to light and maximum biomass characteristics. The variabilities in the DCM profiles in terms of latitude, seasonality, and their response to mesoscale eddies were subsequently investigated on a global scale. Our analysis demonstrates that light and nutrient availability explain a significant portion of the variability in the phytoplankton distribution across different regions and seasons. Statistical analysis reveals that cyclonic (anticyclonic) eddies enhance (weaken) the intensity of the DCM. The magnitude of this enhancement or weakening exhibits regional differences. Specifically, high-latitude regions are more influenced by eddies in terms of light-adapted DCM intensity, while in mid-latitude regions, eddies exhibit a stronger effect on the maximum biomass-driven DCM intensity. Moreover, our findings suggest that eddies in the North Atlantic Subtropical Gyre contribute to a downward shift in the euphotic zone depth, leading to an increased DCM depth and strengthened DCM intensity. However, in the equatorial region, eddies impact the DCM depth by influencing the nitracline (a layer in a body of water in which the nitrate concentration changes rapidly with depth). Similar patterns are frequently observed in different regions at the same latitude, providing a foundation for further detailed investigations of the DCM in specific areas.
Collapse
Affiliation(s)
- Changjie Wang
- School of Marine Sciences, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Fenfen Liu
- School of Marine Sciences, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-sen University, Zhuhai 519082, China.
| |
Collapse
|
3
|
Oviedo L, Pastorino G. Description of the early shell morphology of three species of Pectinidae (Mollusca: Bivalvia) from Argentina. Zootaxa 2023; 5361:427-443. [PMID: 38220749 DOI: 10.11646/zootaxa.5361.3.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Indexed: 01/16/2024]
Abstract
We describe the shell morphology of the prodissoconch and early postlarval shell of Aequipecten tehuelchus (dOrbigny), Flexopecten felipponei (Dall), and Zygochlamys patagonica (King) from the southern coast of Argentina. Aequipecten tehuelchus has a nepioconch microsculpture with fine, dense, and regularly distributed pits. The byssal notch is initially deep and narrow but becomes sinuous at the beginning of the post-nepioconch. The nepioconch of Zygochlamys patagonica has antimarginal riblets; the byssal notch is wider than in A. tehuelchus and does not present the sinuosity observed in the other species. The microsculpture of the nepioconchs of F. felipponei and A. tehuelchus is indistinguishable. The earliest differentiation between the two species appears with the post-nepionic left valve, in which A. tehuelchus exhibits between 15 and 20 primary ribs while F. felipponei displays 28 to 34 faint folds. Zygochlamys patagonica shows 21 to 31 primary and secondary ribs. The taxonomic status of the three species is discussed in light of these findings and with respect to current adult-shell taxonomy and genetic analyses.
Collapse
Affiliation(s)
- Loreley Oviedo
- Ctedra Diversidad Animal I and Laboratorio de Virologa y Gentica Molecular; Facultad de Ciencias Naturales y Ciencias de la Salud; Universidad Nacional de la Patagonia San Juan Bosco; 9 de Julio y Belgrano s/n; 9100 Trelew; Chubut; ARGENTINA.
| | - Guido Pastorino
- Museo Argentino de Ciencias Naturales Bernardino Rivadavia; Av. ngel Gallardo 470; C1405DJR Ciudad Autnoma de Buenos Aires; ARGENTINA.
| |
Collapse
|
4
|
Xiong J, Xue K, Li J, Hu M, Li J, Wang X, Lin C, Ma R, Chen L. Vertical distribution analysis and total mass estimation of nitrogen and phosphorus in large shallow lakes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118465. [PMID: 37418911 DOI: 10.1016/j.jenvman.2023.118465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 05/25/2023] [Accepted: 06/17/2023] [Indexed: 07/09/2023]
Abstract
Analysing the vertical distribution of nutrient salts and estimating the total mass of lake nutrients is helpful for the management of lake nutrient status and the formulation of drainage standards in basins. However, studies on nitrogen (N) and phosphorus (P) in lakes have focused on obtaining measures of N and P concentrations, but no understanding exists on the vertical distribution of N and P in the entire water column. The present study proposes algorithms for estimating the total masses of N/P per unit water column (ALGO-TNmass/ALGO-TPmass) for shallow eutrophic lakes. Using Lake Taihu as an example, the total masses of nutrients in Lake Taihu in the historical period were obtained, and the algorithm performance was discussed. The results showed that the vertical distribution of nutrients decreased with increasing depth and exhibited a quadratic distribution. Surface nutrients and chlorophyll-a concentrations play important roles in the vertical distribution of nutrients. Based on conventional surface water quality indicators, algorithms for the vertical nutrient concentration in Lake Taihu were proposed. Both algorithms had good accuracy (ALGO-TNmass R2 > 0.75, RMSE <0.57; ALGO-TPmass R2 > 0.80, RMSE ≤0.50), the ALGO-TPmass had better applicability than the ALGO-TNmass, and had good accuracy in other shallow lakes. Therefore, deducing the TPmass using conventional water quality indicators in surface water, which not only simplifies the sampling process but also provides an opportunity for remote sensing technology to monitor the total masses of nutrients, is feasible. The long-term average total mass of N was 11,727 t, showing a gradual downward trend before 2010, after which it stabilised. The maximum and minimum intra-annual total N masses were observed in May and November, respectively. The long-term average total mass of P was 512 t, showing a gradual downward trend before 2010, and a slow upward trend thereafter. The maximum and minimum intra-annual total masses of P occurred in August and February or May, respectively. The correlation between the total mass of N and meteorological conditions was not obvious, whereas some influence on the total mass of P was evident, particularly water level and wind speed.
Collapse
Affiliation(s)
- Junfeng Xiong
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Kun Xue
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Jing Li
- Hydrology and Water Resources Department, Nanjing Hydraulic Research Institute, Nanjing, 210029, China
| | - Minqi Hu
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Jiaxin Li
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Xiaoyang Wang
- College of Geometrics, Xi'an University of Science and Technology, Xi'an, 710054, China
| | - Chen Lin
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
| | - Ronghua Ma
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Lei Chen
- State Key Laboratory of Water Quality Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| |
Collapse
|
5
|
Mondal A, Banerjee S. Impact of critical eddy diffusivity on seasonal bloom dynamics of Phytoplankton in a global set of aquatic environments. Sci Rep 2023; 13:17141. [PMID: 37816845 PMCID: PMC10564959 DOI: 10.1038/s41598-023-43745-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 09/27/2023] [Indexed: 10/12/2023] Open
Abstract
The intensity of eddy diffusivity and the spatial average of water velocity at the depths of the water column in oceans and lakes play a fundamental role in phytoplankton production and phytoplankton and zooplankton biomass, and community composition. The critical depth and intensity of turbulent mixing within the water column profoundly affect phytoplankton biomass, which depends on the sinking characteristic of planktonic algal species. We propose an Nutrient-Phytoplankton-Zooplankton (NPZ) model in 3D space with light and nutrient-limited growth in a micro-scale ecological study. To incorporate micro-scale observation of phytoplankton intermittency in bloom mechanism in stationary as well as oceanic turbulent flows, a moment closure method has been applied in this study. Experimental observations imply that an increase in turbulence is sometimes ecologically advantageous for non-motile planktonic algae. How do we ensure whether there will be a bloom cycle or whether there can be any bloom at all when the existing phytoplankton group is buoyant, heavier, motile, or non-motile? To address these questions, we have explored the effects of critical depth, the intensity of eddy diffusivity, spatial average of water velocity, on the concentration as well as horizontal and vertical distribution of phytoplankton and zooplankton biomass using a mathematical model and moment closure technique. We quantify a critical threshold value of eddy diffusivity and the spatial average of water velocity and observe the corresponding changes in the phytoplankton bloom dynamics. Our results highlight the importance of eddy diffusivity and the spatial average of water velocity on seasonal bloom dynamics and also mimic different real-life bloom scenarios in Mikawa Bay (Japan), Tokyo Bay (Japan), Arakawa River (Japan), the Baltic Sea, the North Atlantic Ocean, Gulf Alaska, the North Arabian Sea, the Cantabrian Sea, Lake Nieuwe Meer (Netherlands) and several shallower lakes.
Collapse
Affiliation(s)
- Arpita Mondal
- Department of Mathematics, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Sandip Banerjee
- Department of Mathematics, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India.
| |
Collapse
|
6
|
Li J, Li Y, Liu M, Yu Z, Song D, Jeppesen E, Zhou Q. Patterns of thermocline structure and the deep chlorophyll maximum feature in multiple stratified lakes related to environmental drivers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158431. [PMID: 36055493 DOI: 10.1016/j.scitotenv.2022.158431] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 08/23/2022] [Accepted: 08/27/2022] [Indexed: 06/15/2023]
Abstract
Thermal stratification and the deep chlorophyll maximum (DCM), two commonly related phenomena in stratified lakes, play fundamental roles in eco-environmental processes. However, the progressive linkages among multi-dimensional environmental factors, thermal stratification and DCM were poorly explored, which greatly constrains our understanding of cross-level governance in deep lakes. In this study, the thermocline structure (i.e., thermocline depth, thickness and strength) and DCM feature (depth and thickness) and their driving factors were investigated at regional scale using data from 18 stratified lakes differing in limnological characteristics, Southwest China. Our study showed that (1) DCM occurred close to the thermocline in most lakes (represented by their depth and thickness), (2) the depths of the thermocline and DCM were both shallower than the euphotic depth, and (3) spatial heterogeneity occurred the thermocline structure and the DCM feature, reflecting different environmental factors. Specifically, water depth and light penetration depths were both positively correlated with thermocline depth and thickness and the DCM feature, and ultraviolet radiation (UVR) was more important than photosynthetically active radiation (PAR) for thermocline depth, but PAR was more important for thermocline thickness; moreover, PAR played a more prominent role than UVR for the DCM feature. As there were interactions between some environmental factors, we built a cascading path using a partial least squares path modelling for the DCM feature: lake morphometry directly impacted the thermocline structure and surface water quality; the water quality further affected light penetration depths as well as the thermocline structure; light penetration depth and thermocline structure combined directly determined the DCM feature, where the importance of light was larger. Our findings provide information on the cascading drivers of the thermocline structure and DCM feature in deep lakes and also constitute a valuable reference for deep lake management under the dual pressure of climate change and eutrophication.
Collapse
Affiliation(s)
- Jingyi Li
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China
| | - Yuanrui Li
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China
| | - Miao Liu
- Jiangsu Provincial Academy of Environmental Science, Nanjing 210098, China
| | - Zhirong Yu
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China
| | - Di Song
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Research Academy of Eco-environmental Sciences, Kunming 650034, China
| | - Erik Jeppesen
- Department of Ecoscience and Arctic Research Centre, Aarhus University, Aarhus 8000, Denmark; Sino-Danish Centre for Education and Research, Chinese Academy of Sciences, Beijing 100101, China; Limnology Laboratory, Department of Biological Sciences and Centre for Ecosystem Research and Implementation, Middle East Technical University, Ankara 06800, Turkey; Institute of Marine Sciences, Middle East Technical University, Erdemli-Mersin 33731, Turkey
| | - Qichao Zhou
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China; Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Research Academy of Eco-environmental Sciences, Kunming 650034, China.
| |
Collapse
|
7
|
Manifestation of Spiral Structures under the Action of Upper Ocean Currents. REMOTE SENSING 2022. [DOI: 10.3390/rs14081871] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The traditional approach to the interpretation of spirals observed in radar, optical and radiometric panoramas of a sea surface is based on equating the outer spiral scale with the scale of a manifesting eddy, but the validity of this approach has been poorly studied. Using the maximum cross-correlation (MCC) method for multispectral satellite images containing a spiral structure, we found a significant discrepancy between the structures of horizontal velocity fields and the geometrical characteristics of spiral structures in each band. Each velocity field demonstrated a pair of points of zero velocity with a km-scale difference between their positions in different bands. In order to describe the observed features, an analytical description of the upper-ocean current composed of a spiral eddy and of a homogeneous drift (related, in particular, to wind forcing) is proposed. This simple model states that the spiral characteristics and the position of the spiral center depend on a drift current even when the genuine characteristics of the marine eddy are fixed. The studied example shows that the diameter of an eddy core may significantly (2–3 times) differ from the outer scale of the spiral, which demonstrates the incorrectness of the traditional approach of spiral structures interpretation.
Collapse
|
8
|
Font-Muñoz JS, Sourisseau M, Cohen-Sánchez A, Tuval I, Basterretxea G. Pelagic diatoms communicate through synchronized beacon natural fluorescence signaling. SCIENCE ADVANCES 2021; 7:eabj5230. [PMID: 34910521 PMCID: PMC8673755 DOI: 10.1126/sciadv.abj5230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 10/27/2021] [Indexed: 06/14/2023]
Abstract
Communication between conspecific individuals is an essential part of life both in terrestrial and marine realms. Until recently, social behavior in marine phytoplankton was assumed to rely mainly on the secretion of a variety of infochemicals that allowed population-scale collective responses. Here, we demonstrate that pelagic diatoms also use Sun-stimulated fluorescence signals for synchronizing their behavior. These unicellular microorganisms, playing a key biogeochemical role in the ocean, use photoreceptor proteins and red–far-red fluorescent radiation to communicate. A characteristic beaconing signal is generated by rhythmic organelle displacement within the cell cytoplasm, triggering coordinated population behavior. These light-based communication networks could critically determine major facets of diatom ecology and fitness and regulate the dynamics of larger-scale ocean processes.
Collapse
Affiliation(s)
- Joan S. Font-Muñoz
- IFREMER, French Institute for Sea Research, DYNECO PELAGOS, 29280 Plouzané, France
- Université de Brest-UBO/CNRS/IFREMER/IRD, 29238 Brest, France
| | - Marc Sourisseau
- IFREMER, French Institute for Sea Research, DYNECO PELAGOS, 29280 Plouzané, France
| | - Amanda Cohen-Sánchez
- Mediterranean Institute for Advanced Studies, IMEDEA (UIB-CSIC), Miquel Marques 21, 07190 Esporles, Balearic Islands, Spain
| | - Idan Tuval
- Mediterranean Institute for Advanced Studies, IMEDEA (UIB-CSIC), Miquel Marques 21, 07190 Esporles, Balearic Islands, Spain
- Department of Physics, University of the Balearic Islands, Ctra. Valldemossa Km. 7.5, 07122 Palma, Balearic Islands, Spain
| | - Gotzon Basterretxea
- Mediterranean Institute for Advanced Studies, IMEDEA (UIB-CSIC), Miquel Marques 21, 07190 Esporles, Balearic Islands, Spain
| |
Collapse
|