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Omta AW, Liefer JD, Finkel ZV, Irwin AJ, Sher D, Follows MJ. A model of time-dependent macromolecular and elemental composition of phytoplankton. J Theor Biol 2024:111883. [PMID: 38908474 DOI: 10.1016/j.jtbi.2024.111883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 06/08/2024] [Accepted: 06/14/2024] [Indexed: 06/24/2024]
Abstract
Phytoplankton Chl:C:N:P ratios are important from both an ecological and a biogeochemical perspective. We show that these elemental ratios can be represented by a phytoplankton physiological model of low complexity that includes major cellular macromolecular pools. In particular, our model resolves time-dependent intracellular pools of chlorophyll, proteins, nucleic acids, carbohydrates/lipids, and N and P storage. Batch culture data for two diatom and two prasinophyte species are used to constrain parameters that represent specific allocation traits and strategies. A key novelty is the simultaneous estimation of physiological parameters for two phytoplankton groups of such different sizes. The number of free parameters is reduced by assuming (i) allometric scaling for maximum uptake rates, (ii) shared half-saturation constants for synthesis of functional macromolecules, (iii) shared exudation rates of functional macromolecules across the species. The rationale behind this assumption is that across the different species, the same or similar processes, enzymes, and metabolites play a role in key physiological processes. For the turnover numbers of macromolecular synthesis and storage exudation rates, differences between diatoms and prasinophytes need to be taken into account to obtain a good fit. Our model fits suggest that the parameters related to storage dynamics dominate the differences in the C:N:P ratios between the different phytoplankton groups. Since descriptions of storage dynamics are still incomplete and imprecise, predictions of C:N:P ratios by phytoplankton models likely have a large uncertainty.
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Affiliation(s)
- Anne Willem Omta
- Department of Earth, Environmental, and Planetary Sciences, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
| | - Justin D Liefer
- Department of Biology, Mount Allison University, 63B York Street, Sackville, E4L 1A5, New Brunswick, Canada
| | - Zoe V Finkel
- Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax, B3H 4R2, Nova Scotia, Canada
| | - Andrew J Irwin
- Department of Mathematics and Statistics, Dalhousie University, 6316 Coburg Road, Halifax, B3H 4R2, Nova Scotia, Canada
| | - Daniel Sher
- Leon H. Charney School of Marine Sciences, University of Haifa, Mount Carmel 31905, Haifa, Israel
| | - Michael J Follows
- Department of Earth, Atmospheric and Planetary Sciences, MIT, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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2
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Li J, Li W, Huang Y, Bu H, Zhang K, Lin S. Phosphorus limitation intensifies heat-stress effects on the potential mutualistic capacity in the coral-derived Symbiodinium. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:173912. [PMID: 38871329 DOI: 10.1016/j.scitotenv.2024.173912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 05/08/2024] [Accepted: 06/08/2024] [Indexed: 06/15/2024]
Abstract
Coral reef ecosystems have been severely ravaged by global warming and eutrophication. Eutrophication often originates from nitrogen (N) overloading that creates stoichiometric phosphorus (P) limitation, which can be aggravated by sea surface temperature rises that enhances stratification. However, how P-limitation interacts with thermal stress to impact coral-Symbiodiniaceae mutualism is poorly understood and underexplored. Here, we investigated the effect of P-limitation (P-depleted vs. P-replete) superimposed on heat stress (31 °C vs. 25 °C) on a Symbiodinium strain newly isolated from the coral host by a 14-day incubation experiment. The heat and P-limitation co-stress induced an increase in alkaline phosphatase activity and reppressed cell division, photosynthetic efficiency, and expression of N uptake and assimilation genes. Moreover, P limitation intensified downregulation of carbon fixation (light and dark reaction) and metabolism (glycolysis) pathways in heat stressed Symbiodinium. Notably, co-stress elicited a marked transcriptional downregulation of genes encoding photosynthates transporters and microbe-associated molecular patterns, potentially undermining the mutualism potential. This work sheds light on the interactive effects of P-limitation and heat stress on coral symbionts, indicating that nutrient imbalance in the coral reef ecosystem can intensify heat-stress effects on the mutualistic capacity of Symbiodiniaceae.
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Affiliation(s)
- Jiashun Li
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Wenzhe Li
- State Key Laboratory of Marine Resource Utilization in the South China Sea and School of Marine Biology and Fisheries, Hainan University, Haikou, China
| | - Yulin Huang
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Hailu Bu
- State Key Laboratory of Marine Resource Utilization in the South China Sea and School of Marine Biology and Fisheries, Hainan University, Haikou, China
| | - Kaidian Zhang
- State Key Laboratory of Marine Resource Utilization in the South China Sea and School of Marine Biology and Fisheries, Hainan University, Haikou, China.
| | - Senjie Lin
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA.
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Shu H, Shen Y, Wang H, Sun X, Ma J, Lin X. Biogenic Phosphonate Utilization by Globally Distributed Diatom Thalassiosira pseudonana. Microorganisms 2024; 12:761. [PMID: 38674705 PMCID: PMC11051927 DOI: 10.3390/microorganisms12040761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/29/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024] Open
Abstract
Phosphonates are a class of organic phosphorus (P) compounds that contribute ~25% of dissolved organic P. Recent studies reveal the important role of phosphonates mediated by prokaryotes in the marine P redox cycle. However, its bioavailability by eukaryotic phytoplankton is under debate. 2-Aminoethylphosphonic acid (2-AEP) and 2-amino-3-phosphonopropionic acid (2-AP3) are two biogenic phosphonates in the marine environment. Here, Thalassiosira pseudonana, a common diatom species in the ocean, is able to recover growth from P starvation when provided with 2-AEP and 2-AP3. Moreover, 2-AEP cultures exhibited a more similar growth rate at 12 °C than at 25 °C when compared with inorganic P cultures. The cellular stoichiometry of 2-AEP groups was further determined, the values of which are in-between the P-depleted and DIP-replete cultures. This study provides evidence that biogenic phosphonates could be adopted as alternative P sources to support diatom growth and may provide physiological adaptation.
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Affiliation(s)
- Huilin Shu
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; (H.S.); (Y.S.); (H.W.); (X.S.); (J.M.)
- College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
- College of Life Sciences, Jiangxi Normal University, Nanchang 330022, China
| | - Yuan Shen
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; (H.S.); (Y.S.); (H.W.); (X.S.); (J.M.)
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Hongwei Wang
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; (H.S.); (Y.S.); (H.W.); (X.S.); (J.M.)
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Xueqiong Sun
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; (H.S.); (Y.S.); (H.W.); (X.S.); (J.M.)
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Jian Ma
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; (H.S.); (Y.S.); (H.W.); (X.S.); (J.M.)
- College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
| | - Xin Lin
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; (H.S.); (Y.S.); (H.W.); (X.S.); (J.M.)
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
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4
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Harcourt R, Garcia NS, Martiny AC. Intraspecific trait variation modulates the temperature effect on elemental quotas and stoichiometry in marine Synechococcus. PLoS One 2024; 19:e0292337. [PMID: 38498438 PMCID: PMC10947687 DOI: 10.1371/journal.pone.0292337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 02/26/2024] [Indexed: 03/20/2024] Open
Abstract
Diverse phytoplankton modulate the coupling between the ocean carbon and nutrient cycles through life-history traits such as cell size, elemental quotas, and ratios. Biodiversity is mostly considered at broad functional levels, but major phytoplankton lineages are themselves highly diverse. As an example, Synechococcus is found in nearly all ocean regions, and we demonstrate contains extensive intraspecific variation. Here, we grew four closely related Synechococcus isolates in serially transferred cultures across a range of temperatures (16-25°C) to quantify for the relative role of intraspecific trait variation vs. environmental change. We report differences in cell size (p<0.01) as a function of strain and clade (p<0.01). The carbon (QC), nitrogen (QN), and phosphorus (QP) cell quotas all increased with cell size. Furthermore, cell size has an inverse relationship to growth rate. Within our experimental design, temperature alone had a weak physiological effect on cell quota and elemental ratios. Instead, we find systemic intraspecific variance of C:N:P, with cell size and N:P having an inverse relationship. Our results suggest a key role for intraspecific life history traits in determining elemental quotas and stoichiometry. Thus, the extensive biodiversity harbored within many lineages may modulate the impact of environmental change on ocean biogeochemical cycles.
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Affiliation(s)
- Renne Harcourt
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, United States of America
| | - Nathan S. Garcia
- Department of Earth System Science, University of California, Irvine, California, United States of America
| | - Adam C. Martiny
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, United States of America
- Department of Earth System Science, University of California, Irvine, California, United States of America
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5
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Zhang XY, Li ZF, Gu HF, Han AQ, Han FX, Ou LJ. Significance of phosphate adsorbed on the cellular surface as a storage pool and its regulation in marine microalgae. MARINE ENVIRONMENTAL RESEARCH 2024; 195:106378. [PMID: 38266549 DOI: 10.1016/j.marenvres.2024.106378] [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: 09/24/2023] [Revised: 01/07/2024] [Accepted: 01/19/2024] [Indexed: 01/26/2024]
Abstract
The increasing prevalence of phosphorus limitation in coastal waters has drawn attention to the bioavailability of cellular surface-adsorbed phosphorus (SP) as a reservoir of phosphorus in phytoplankton. This study examined the storage, utilization, and regulation of SP in the coastal waters of the East China Sea, as well as three cultivated algal bloom species (Skeletonema marinoi, Prorocentrum shikokuense, and Karenia mikimotoi) prevalent in the area. SP accounted for 14.3%-45.5% of particulate phosphorus in the field and laboratory species. After the depletion of external phosphate, the studied species can rapidly transport SP within 3-24 h. The storage of SP is regulated by both external phosphate conditions and the internal growth stage of cells, but it is not influenced by the various cellular surface structures of the studied species. This study highlights the significance of SP as a crucial phosphorus reservoir and the potential use of the SP level as an indicator of phosphorus deficiency in phytoplankton.
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Affiliation(s)
- Xian-Yang Zhang
- Research Center of Harmful Algae and Marine Biology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Jinan University, Guangzhou, China
| | - Zhuo-Fan Li
- Research Center of Harmful Algae and Marine Biology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Jinan University, Guangzhou, China
| | - Hai-Feng Gu
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
| | - Ai-Qin Han
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
| | - Feng-Xian Han
- Analytical and Testing Center, Jinan University, Guangzhou, China.
| | - Lin-Jian Ou
- Research Center of Harmful Algae and Marine Biology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Jinan University, Guangzhou, China.
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6
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Garcia NS, Du M, Guindani M, McIlvin MR, Moran DM, Saito MA, Martiny AC. Proteome trait regulation of marine Synechococcus elemental stoichiometry under global change. THE ISME JOURNAL 2024; 18:wrae046. [PMID: 38513256 PMCID: PMC11020310 DOI: 10.1093/ismejo/wrae046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 02/27/2024] [Accepted: 03/19/2024] [Indexed: 03/23/2024]
Abstract
Recent studies have demonstrated regional differences in marine ecosystem C:N:P with implications for carbon and nutrient cycles. Due to strong co-variance, temperature and nutrient stress explain variability in C:N:P equally well. A reductionistic approach can link changes in individual environmental drivers with changes in biochemical traits and cell C:N:P. Thus, we quantified effects of temperature and nutrient stress on Synechococcus chemistry using laboratory chemostats, chemical analyses, and data-independent acquisition mass spectrometry proteomics. Nutrient supply accounted for most C:N:Pcell variability and induced tradeoffs between nutrient acquisition and ribosomal proteins. High temperature prompted heat-shock, whereas thermal effects via the "translation-compensation hypothesis" were only seen under P-stress. A Nonparametric Bayesian Local Clustering algorithm suggested that changes in lipopolysaccharides, peptidoglycans, and C-rich compatible solutes may also contribute to C:N:P regulation. Physiological responses match field-based trends in ecosystem stoichiometry and suggest a hierarchical environmental regulation of current and future ocean C:N:P.
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Affiliation(s)
- Nathan S Garcia
- Department of Earth System Science, University of California, Irvine, Irvine, CA 92697, United States
| | - Mingyu Du
- Department of Statistics, University of California, Irvine, Irvine, CA 92697, United States
| | - Michele Guindani
- Department of Biostatistics, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Matthew R McIlvin
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States
| | - Dawn M Moran
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States
| | - Mak A Saito
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States
| | - Adam C Martiny
- Department of Earth System Science, University of California, Irvine, Irvine, CA 92697, United States
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA 92697, United States
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7
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Zhao H, Yang S, Qin X, Huang J, Huang H, Li W, Jiang G, Tang J, Dong K, Li N. Disentangling the Ecological Processes and Driving Forces Shaping the Seasonal Pattern of Halobacteriovorax Communities in a Subtropical Estuary. MICROBIAL ECOLOGY 2023; 86:1881-1892. [PMID: 36799977 DOI: 10.1007/s00248-023-02195-w] [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: 10/25/2022] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
Halobacteriovorax are predatory bacteria that have a significant ecological role in marine environments. However, understanding of dynamics of populations, driving forces, and community composition of Halobacteriovorax groups in natural marine environments is still limited. Here, we used high-throughput sequencing to study the underlying mechanisms governing the diversity and assembly of the Halobacteriovorax community at spatiotemporal scales in a subtropical estuary. Phylogenetic analysis showed that 10 of 15 known Halobacteriovorax clusters were found in the studied estuary. Halobacteriovorax α-diversity and β-diversity exhibited significant seasonal variation. Variation partitioning analysis showed that the effect of nutrients was greater than that of other measured water properties on Halobacteriovorax community distribution. The results of Spearman's and Mantel's tests indicated that the trophic pollutants dissolved inorganic phosphorus (DIP) and NH4+-N in the estuary were the key factors that significantly affected Halobacteriovorax species and community diversity. In addition, this work indicated that the biological stoichiometry (especially N/P) of nutrients exerted a significant influence on the Halobacteriovorax community. Furthermore, we found that both deterministic and stochastic processes contributed to the turnover of Halobacteriovorax communities, and environmental filtering dominated the assembly of estuarine Halobacteriovorax communities. Overall, we provide new insights into the mechanisms in the generation and maintenance of the Halobacteriovorax community in marine environments.
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Affiliation(s)
- Huaxian Zhao
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Shu Yang
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Xinyi Qin
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Jiongqing Huang
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Haifeng Huang
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Wenjing Li
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Gonglingxia Jiang
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Jinli Tang
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China
| | - Ke Dong
- Department of Biological Sciences, Kyonggi University, 154-42, Gwanggyosan-ro, Yeongtong-gu Gyeonggi-do, Suwon-si, 16227, South Korea
| | - Nan Li
- Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, Nanning, 530001, China.
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Li J, Zhang K, Li L, Wang Y, Wang C, Lin S. Two-sided effects of the organic phosphorus phytate on a globally important marine coccolithophorid phytoplankton. Microbiol Spectr 2023; 11:e0125523. [PMID: 37702480 PMCID: PMC10655706 DOI: 10.1128/spectrum.01255-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/05/2023] [Indexed: 09/14/2023] Open
Abstract
Dissolved organic phosphorus (DOP) is a potential source of aquatic eutrophication and pollution because it can potentially stimulate growth in some species and inhibit growth in other species of algae, the foundation of the marine ecosystem. Inositol hexaphosphate (also named phytic acid or PA), an abundant organophosphate, is presumably ubiquitous in the marine environment, but how it affects marine primary producers is poorly understood. Here, we investigated the bioavailability of this DOP to the cosmopolitan coccolithophore Emiliania huxleyi. Our results showed that E. huxleyi cells can take up PA and dissolved inorganic phosphorus (DIP) simultaneously. Absorbed PA can efficiently support algal growth, producing cell yield between DIP and phosphorus (P)-depleted conditions. Accordingly, PA supply as the sole P source highly influences cellular metabolism and nutrient stoichiometry. Particularly, PA-grown cultures exhibited enhanced carbon fixation, increased lipid content, activated energy metabolism, and induced nitrogen assimilation. However, our data suggest that PA may also exert some levels of toxic effects on E. huxleyi. This study provides novel insights into the variable effects of a DOP on marine phytoplankton, which will inform new inquiries about how the complex DOP constituencies in the ocean will shape phytoplankton community structure and function. IMPORTANCE The dissolved organic phosphorus (DOP) utilization in phytoplankton plays vital roles in cellular P homeostasis, P-nutrient niche, and the dynamics of community structure in marine ecosystems, but its mechanisms, potentially varying with species, are far from clear. In this study, we investigated the utilization of a widespread DOP species, which is commonly produced by plants (land plants and marine macrophytes) and released into coastal areas, in a globally distributed bloom-forming coccolithophore species in various phosphorus environments. Using a combination of physiological and transcriptomic measurements and analyses, our experimental results revealed the complex mechanism and two-sided effects of DOP (major algal growth-supporting and minor toxic effects) in this species, providing a novel perspective on phytoplankton nutrient regulation.
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Affiliation(s)
- Jiashun Li
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, Fujian, China
| | - Kaidian Zhang
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, China
| | - Ling Li
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, Fujian, China
| | - Yujie Wang
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, Fujian, China
| | - Cong Wang
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, Fujian, China
| | - Senjie Lin
- Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration, State Key Laboratory of Marine Environmental Science, and College of Ocean and Earth Sciences, Xiamen University, Xiamen, Fujian, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory of Marine Science and Technology, Qingdao, Shandong, China
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut, USA
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9
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Chien CT, Pahlow M, Schartau M, Li N, Oschlies A. Effects of phytoplankton physiology on global ocean biogeochemistry and climate. SCIENCE ADVANCES 2023; 9:eadg1725. [PMID: 37494440 PMCID: PMC10371029 DOI: 10.1126/sciadv.adg1725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 06/22/2023] [Indexed: 07/28/2023]
Abstract
The similarity of the average ratios of nitrogen (N) and phosphorus (P) in marine dissolved inorganic and particulate organic matter, dN:P and pN:P, respectively, indicates tight links between those pools in the world ocean. Here, we analyze this linkage by varying phytoplankton N and P subsistence quotas in an optimality-based ecosystem model coupled to an Earth system model. The analysis of our ensemble of simulations discloses various feedbacks between changes in the N and P quotas, N2 fixation, and denitrification that weaken the often-hypothesized tight coupling between dN:P and pN:P. We demonstrate the importance of particulate N:C and P:C ratios for regulating dN:P on the global scale, with marine oxygen level being an important control. Our analysis provides further insight into the potential interdependence of phytoplankton physiology and global climate conditions.
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Affiliation(s)
- Chia-Te Chien
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Markus Pahlow
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Markus Schartau
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Na Li
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Andreas Oschlies
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
- Kiel University, 24118 Kiel, Germany
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10
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Alonso-Sáez L, Palacio AS, Cabello AM, Robaina-Estévez S, González JM, Garczarek L, López-Urrutia Á. Transcriptional Mechanisms of Thermal Acclimation in Prochlorococcus. mBio 2023:e0342522. [PMID: 37052490 DOI: 10.1128/mbio.03425-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023] Open
Abstract
Low temperature limits the growth and the distribution of the key oceanic primary producer Prochlorococcus, which does not proliferate above a latitude of ca. 40°. Yet, the molecular basis of thermal acclimation in this cyanobacterium remains unexplored. We analyzed the transcriptional response of the Prochlorococcus marinus strain MIT9301 in long-term acclimations and in natural Prochlorococcus populations along a temperature range enabling its growth (17 to 30°C). MIT9301 upregulated mechanisms of the global stress response at the temperature minimum (17°C) but maintained the expression levels of genes involved in essential metabolic pathways (e.g., ATP synthesis and carbon fixation) along the whole thermal niche. Notably, the declining growth of MIT9301 from the optimum to the minimum temperature was coincident with a transcriptional suppression of the photosynthetic apparatus and a dampening of its circadian expression patterns, indicating a loss in their regulatory capacity under cold conditions. Under warm conditions, the cellular transcript inventory of MIT9301 was strongly streamlined, which may also induce regulatory imbalances due to stochasticity in gene expression. The daytime transcriptional suppression of photosynthetic genes at low temperature was also observed in metatranscriptomic reads mapping to MIT9301 across the global ocean, implying that this molecular mechanism may be associated with the restricted distribution of Prochlorococcus to temperate zones. IMPORTANCE Prochlorococcus is a major marine primary producer with a global impact on atmospheric CO2 fixation. This cyanobacterium is widely distributed across the temperate ocean, but virtually absent at latitudes above 40° for yet unknown reasons. Temperature has been suggested as a major limiting factor, but the exact mechanisms behind Prochlorococcus thermal growth restriction remain unexplored. This study brings us closer to understanding how Prochlorococcus functions under challenging temperature conditions, by focusing on its transcriptional response after long-term acclimation from its optimum to its thermal thresholds. Our results show that the drop in Prochlorococcus growth rate under cold conditions was paralleled by a transcriptional suppression of the photosynthetic machinery during daytime and a loss in the organism's regulatory capacity to maintain circadian expression patterns. Notably, warm temperature induced a marked shrinkage of the organism's cellular transcript inventory, which may also induce regulatory imbalances in the future functioning of this cyanobacterium.
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Affiliation(s)
- Laura Alonso-Sáez
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Antonio S Palacio
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Ana M Cabello
- AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | | | - José M González
- Department of Microbiology, University of La Laguna, La Laguna, Spain
| | - Laurence Garczarek
- Sorbonne Université, CNRS, UMR 7144 Adaptation and Diversity in the Marine Environment (AD2M), Station Biologique de Roscoff (SBR), Roscoff, France
| | - Ángel López-Urrutia
- Centro Oceanográfico de Gijón, Instituto Español de Oceanografía, IEO-CSIC, Gijón, Asturias, Spain
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11
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Global Ocean Particulate Organic Phosphorus, Carbon, Oxygen for Respiration, and Nitrogen (GO-POPCORN). Sci Data 2022; 9:688. [DOI: 10.1038/s41597-022-01809-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 10/25/2022] [Indexed: 11/13/2022] Open
Abstract
AbstractConcentrations and elemental stoichiometry of suspended particulate organic carbon, nitrogen, phosphorus, and oxygen demand for respiration (C:N:P:−O2) play a vital role in characterizing and quantifying marine elemental cycles. Here, we present Version 2 of the Global Ocean Particulate Organic Phosphorus, Carbon, Oxygen for Respiration, and Nitrogen (GO-POPCORN) dataset. Version 1 is a previously published dataset of particulate organic matter from 70 different studies between 1971 and 2010, while Version 2 is comprised of data collected from recent cruises between 2011 and 2020. The combined GO-POPCORN dataset contains 2673 paired surface POC/N/P measurements from 70°S to 73°N across all major ocean basins at high spatial resolution. Version 2 also includes 965 measurements of oxygen demand for organic carbon respiration. This new dataset can help validate and calibrate the next generation of global ocean biogeochemical models with flexible elemental stoichiometry. We expect that incorporating variable C:N:P:-O2 into models will help improve our estimates of key ocean biogeochemical fluxes such as carbon export, nitrogen fixation, and organic matter remineralization.
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Tanioka T, Garcia CA, Larkin AA, Garcia NS, Fagan AJ, Martiny AC. Global patterns and predictors of C:N:P in marine ecosystems. COMMUNICATIONS EARTH & ENVIRONMENT 2022; 3:271. [PMID: 36407846 PMCID: PMC9640808 DOI: 10.1038/s43247-022-00603-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 10/21/2022] [Indexed: 06/08/2023]
Abstract
Oceanic nutrient cycles are coupled, yet carbon-nitrogen-phosphorus (C:N:P) stoichiometry in marine ecosystems is variable through space and time, with no clear consensus on the controls on variability. Here, we analyze hydrographic, plankton genomic diversity, and particulate organic matter data from 1970 stations sampled during a global ocean observation program (Bio-GO-SHIP) to investigate the biogeography of surface ocean particulate organic matter stoichiometry. We find latitudinal variability in C:N:P stoichiometry, with surface temperature and macronutrient availability as strong predictors of stoichiometry at high latitudes. Genomic observations indicated community nutrient stress and suggested that nutrient supply rate and nitrogen-versus-phosphorus stress are predictive of hemispheric and regional variations in stoichiometry. Our data-derived statistical model suggests that C:P and N:P ratios will increase at high latitudes in the future, however, changes at low latitudes are uncertain. Our findings suggest systematic regulation of elemental stoichiometry among ocean ecosystems, but that future changes remain highly uncertain.
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Affiliation(s)
- Tatsuro Tanioka
- Department of Earth System Science, University of California Irvine, Irvine, CA USA
| | - Catherine A. Garcia
- Department of Earth System Science, University of California Irvine, Irvine, CA USA
- Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawaii at Manoa, Honolulu, HI USA
| | - Alyse A. Larkin
- Department of Earth System Science, University of California Irvine, Irvine, CA USA
| | - Nathan S. Garcia
- Department of Earth System Science, University of California Irvine, Irvine, CA USA
| | - Adam J. Fagan
- Department of Earth System Science, University of California Irvine, Irvine, CA USA
| | - Adam C. Martiny
- Department of Earth System Science, University of California Irvine, Irvine, CA USA
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA USA
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13
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Li J, Zhang K, Li L, Wang Y, Lin S. Unsuspected functions of alkaline phosphatase PhoD in the diatom Phaeodactylum tricornutum. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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14
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Effect of Rising Temperature and Carbon Dioxide on the Growth, Photophysiology, and Elemental Ratios of Marine Synechococcus: A Multistressor Approach. SUSTAINABILITY 2022. [DOI: 10.3390/su14159508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Marine picocyanobacteria belonging to the genus Synechococcus are one of the most abundant photosynthetic organisms on Earth. They are often exposed to large fluctuations in temperature and CO2 concentrations in the ocean, which are expected to further change in the coming decades due to ocean acidification and warming resulting from rising atmospheric CO2 levels. To decipher the effect of changing temperature and CO2 levels on Synechococcus, six Synechococcus strains previously isolated from various coastal and open ocean sites were exposed to a matrix of three different temperatures (22 °C, 24 °C and 26 °C) and CO2 levels (400 ppm, 600 ppm and 800 ppm). Thereafter, the specific growth rates, photophysiological parameters (σPSII and Fv/Fm), C/N (mol/mol) ratios and the nitrogen stable isotopic composition (δ15N (‰)) of the strains were measured. Temperature was found to be a stronger driver of the changes in specific growth rates and photophysiology in the Synechococcus strains. Carbon-concentrating mechanisms (CCM) operational in these strains that shield the photosynthetic machinery from directly sensing ambient changes in CO2 possibly played a major role in causing minimal changes in the specific growth rates under the varying CO2 levels.
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15
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de la Vega C, Buchanan PJ, Tagliabue A, Hopkins JE, Jeffreys RM, Frie AK, Biuw M, Kershaw J, Grecian J, Norman L, Smout S, Haug T, Mahaffey C. Multi-decadal environmental change in the Barents Sea recorded by seal teeth. GLOBAL CHANGE BIOLOGY 2022; 28:3054-3065. [PMID: 35202506 PMCID: PMC9314922 DOI: 10.1111/gcb.16138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/09/2022] [Accepted: 02/13/2022] [Indexed: 06/14/2023]
Abstract
Multiple environmental forcings, such as warming and changes in ocean circulation and nutrient supply, are affecting the base of Arctic marine ecosystems, with cascading effects on the entire food web through bottom-up control. Stable nitrogen isotopes (δ15 N) can be used to detect and unravel the impact of these forcings on this unique ecosystem, if the many processes that affect the δ15 N values are constrained. Combining unique 60-year records from compound specific δ15 N biomarkers on harp seal teeth alongside state-of-the-art ocean modelling, we observed a significant decline in the δ15 N values at the base of the Barents Sea food web from 1951 to 2012. This strong and persistent decadal trend emerges due to the combination of anthropogenic atmospheric nitrogen deposition in the Atlantic, increased northward transport of Atlantic water through Arctic gateways and local feedbacks from increasing Arctic primary production. Our results suggest that the Arctic ecosystem has been responding to anthropogenically induced local and remote drivers, linked to changing ocean biology, chemistry and physics, for at least 60 years. Accounting for these trends in δ15 N values at the base of the food web is essential to accurately detect ecosystem restructuring in this rapidly changing environment.
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Affiliation(s)
- Camille de la Vega
- School of Environmental SciencesUniversity of LiverpoolLiverpoolUK
- Present address:
Leibniz Institute for Baltic Sea Research, WarnemündeRostock18119Germany
| | | | | | | | | | | | - Martin Biuw
- Institute of Marine ResearchFram CentreTromsøNorway
| | - Joanna Kershaw
- Sea Mammal Research UnitScottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
| | - James Grecian
- Sea Mammal Research UnitScottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
| | - Louisa Norman
- School of Environmental SciencesUniversity of LiverpoolLiverpoolUK
| | - Sophie Smout
- Sea Mammal Research UnitScottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
| | - Tore Haug
- Institute of Marine ResearchFram CentreTromsøNorway
| | - Claire Mahaffey
- School of Environmental SciencesUniversity of LiverpoolLiverpoolUK
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16
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Liu K, Ng HYT, Gao Z, Liu H. Selective Feeding of a Mixotrophic Dinoflagellate (Lepidodinium sp.) in Response to Experimental Warming and Inorganic Nutrient Imbalance. Front Microbiol 2022; 13:805306. [PMID: 35516439 PMCID: PMC9063636 DOI: 10.3389/fmicb.2022.805306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 03/14/2022] [Indexed: 11/13/2022] Open
Abstract
Mixotrophic protists are widely observed in the aquatic ecosystems, while how they respond to inorganic nutrient imbalance and ocean warming remains understudied. We conducted a series of experiments on a mixotrophic dinoflagellate Lepidodinium sp. isolated from subtropical coastal waters to investigate the combined effect of temperature and medium nitrate to phosphate ratio (N:P ratio) on the ingestion activities of mixotrophic protists. We found Lepidodinium sp. displayed selective feeding behaviour with a higher ingestion rate on high-N prey (N-rich Rhodomonas salina) when the ambient inorganic N:P ratio was equal to or below the Redfield ratio. The Chesson selectivity index α increased with increasing temperature, suggesting that warming exacerbated the selective feeding of Lepidodinium sp. Under inorganic nitrogen sufficient conditions (N:P ratio = 64), no selective feeding was observed at 25 and 28°C, while it occurs at 31°C, which also indicates that warming alters the feeding behaviour of Lepidodinium sp. In addition, our results revealed that the total ingestion rate of Lepidodinium sp. under the condition with normal inorganic nutrients (Redfield ratio) was significantly lower than that under nutrient-imbalanced conditions, which indicates that Lepidodinium sp. developed compensatory feeding to balance their cellular stoichiometry and satisfy their growth. Our study is the first attempt on revealing the selective feeding behaviours of mixotrophic protists on prey under different inorganic nutrient environments and rising temperatures, which will contribute to our understanding of the response of marine plankton food web to projected climate changes.
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Affiliation(s)
- Kailin Liu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Herrick Yin-To Ng
- Department of Ocean Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Zuyuan Gao
- Department of Ocean Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Hongbin Liu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
- State Key Laboratory of Marine Pollution, Hong Kong SAR, China
- *Correspondence: Hongbin Liu,
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Sharma D, Biswas H, Bandyopadhyay D. Simulated ocean acidification altered community composition and growth of a coastal phytoplankton assemblage (South West coast of India, eastern Arabian Sea). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:19244-19261. [PMID: 34714479 DOI: 10.1007/s11356-021-17141-x] [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: 05/13/2021] [Accepted: 10/15/2021] [Indexed: 06/13/2023]
Abstract
Marine phytoplankton can be highly sensitive to ocean acidification; however, their responses are diverse and therefore, phytoplankton response study on the regional scale is of high research priority. The present study documented the community shift and growth responses of a natural phytoplankton assemblage from the South West coastal water of India (South Eastern Arabian Sea) under ambient CO2 (A-CO2 ≈ 400 µatm) and high CO2 (H-CO2 ≈ 830 µatm) levels in microcosms during the winter monsoon. A doubling of pCO2 resulted in increased cell density, particulate organic carbon and nitrogen (POC, PON) contents, and C:N ratios. The depleted values of δ13CPOC in the H-CO2-incubated cells indicated a higher diffusive CO2 influx. HPLC marker pigment analysis revealed that the community was microphytoplankton dominated (mostly diatoms); nanoplanktonic prymnesiophytic algae and picoplanktonic cyanobacteria showed insignificant response to the simulated ocean acidification. A high CO2-induced increased growth rate was noticed in 6 diatoms (Leptocylindrus danicus; Rhizosolenia setigera; Navicula sp., Asterionella glacialis, Dactyliosolen fragilissimus, and Thalassiosira sp.). The cell volumes of Thalassionema frauenfeldii, Asterionella glacialis, and Cylindrotheca closterium increased significantly, whereas Rhizosolenia setigera and Thalassiosira sp. showed decreased cell volume at the elevated CO2 levels. These changes in growth rate, cell volume, and elemental stoichiometry could be related to CO2 acquisition and the nutritional status of the cells. Some phytoplankton genera from this region are probably acclimatized to pCO2 fluctuations and are likely to benefit from the future increase in CO2 levels. Higher POC production and increased C:N ratio along with variable cell volume may impact the trophic transfer and cycling of organic carbon in this coastal water. However, a multi-stressor approach in a longer experimental exposure should be considered in future research.
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Affiliation(s)
- Diksha Sharma
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403 004, India
| | - Haimanti Biswas
- Biological Oceanography Division, CSIR National Institute of Oceanography, Dona Paula, Goa, 403 004, India.
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18
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Pfister CA, Light SH, Bohannan B, Schmidt T, Martiny A, Hynson NA, Devkota S, David L, Whiteson K. Conceptual Exchanges for Understanding Free-Living and Host-Associated Microbiomes. mSystems 2022; 7:e0137421. [PMID: 35014872 PMCID: PMC8751383 DOI: 10.1128/msystems.01374-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2021] [Indexed: 12/26/2022] Open
Abstract
Whether a microbe is free-living or associated with a host from across the tree of life, its existence depends on a limited number of elements and electron donors and acceptors. Yet divergent approaches have been used by investigators from different fields. The "environment first" research tradition emphasizes thermodynamics and biogeochemical principles, including the quantification of redox environments and elemental stoichiometry to identify transformations and thus an underlying microbe. The increasingly common "microbe first" research approach benefits from culturing and/or DNA sequencing methods to first identify a microbe and encoded metabolic functions. Here, the microbe itself serves as an indicator for environmental conditions and transformations. We illustrate the application of both approaches to the study of microbiomes and emphasize how both can reveal the selection of microbial metabolisms across diverse environments, anticipate alterations to microbiomes in host health, and understand the implications of a changing climate for microbial function.
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Affiliation(s)
- Catherine A. Pfister
- Department of Ecology & Evolution and The Microbiome Center, University of Chicago, Chicago, Illinois, USA
| | - Samuel H. Light
- Department of Microbiology & Duchossois Family Institute, University of Chicago, Chicago, Illinois, USA
| | - Brendan Bohannan
- Environmental Studies and Biology, University of Oregon, Eugene, Oregon, USA
| | - Thomas Schmidt
- Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Adam Martiny
- Earth System Science & Ecology and Evolutionary Biology, University of California Irvine, Irvine, California, USA
| | - Nicole A. Hynson
- Pacific Biosciences Research Center, University of Hawaii at Manoa, Honolulu, Hawaii, USA
| | - Suzanne Devkota
- Microbiome Research, F. Widjaja Foundation Inflammatory Bowel and Immunobiology Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Lawrence David
- Molecular Genetics & Microbiology, Duke University, Durham, North Carolina, USA
| | - Katrine Whiteson
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, USA
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19
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Sauterey B, Ward BA. Environmental control of marine phytoplankton stoichiometry in the North Atlantic Ocean. Proc Natl Acad Sci U S A 2022; 119:e2114602118. [PMID: 34949718 PMCID: PMC8740720 DOI: 10.1073/pnas.2114602118] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/17/2021] [Indexed: 01/14/2023] Open
Abstract
The stoichiometric coupling of carbon to limiting nutrients in marine phytoplankton regulates the magnitude of biological carbon sequestration in the ocean. While clear links between plankton C:N ratios and environmental drivers have been identified, the nature and direction of these links, as well as their underlying physiological and ecological controls, remain uncertain. We show, with a well-constrained mechanistic model of plankton ecophysiology, that while nitrogen availability and temperature emerge as the main drivers of phytoplankton C:N stoichiometry in the North Atlantic, the biological mechanisms involved vary depending on the spatiotemporal scale and region considered. We find that phytoplankton C:N stoichiometry is overall controlled by nitrogen availability below 40° N, predominantly driven by ecoevolutionary shifts in the functional composition of the phytoplankton communities, while phytoplankton stoichiometric plasticity in response to dropping temperatures and increased grazing pressure dominates at higher latitudes. Our findings highlight the potential of "organisms-to-ecosystems" modeling approaches based on mechanistic models of plankton biology accounting for physiology, ecology, and trait evolution to explore and explain complex observational data and ultimately improve the predictions of global ocean models.
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Affiliation(s)
- Boris Sauterey
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721;
- Institut de Biologie de l'École Normale Supérieure, CNRS, INSERM, Université Paris Sciences et Lettres, 75005 Paris, France
| | - Ben A Ward
- Ocean and Earth Science, University of Southampton, SO14 3ZH Southampton, United Kingdom
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20
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Growth and Nutrient Uptake Characteristics of Heterosigma akashiwo (Raphidophyceae) under Nitrogen and Phosphorus Concentrations in the East China Sea. WATER 2021. [DOI: 10.3390/w13223166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Heterosigma akashiwo is classified as a harmful algal bloom (HAB) species that frequently occurs in eutrophic coastal waters and results in the contamination and mortality of fish and shellfish. The growth of H. akashiwo in four phosphate and nitrate concentration scenarios, representing the observed nutrient concentration ranges in the East China Sea (ECS), was evaluated to further understand the effect of nutrient concentrations on H. akashiwo blooms. The specific growth rate in the exponential growth phase (µ′) and the maximum cell density were lower (17–21% and 41%, respectively) under low phosphorus concentration scenarios, compared to the rates observed under high phosphorus concentration scenarios. The cellular nitrogen-to-phosphorus ratios of H. akashiwo were influenced by the initially supplied N:P ratio and the allocation strategy employed. Phosphorus concentration had a greater influence on the total growth of H. akashiwo than nitrate did, within the natural nutrient conditions of the ECS. These results could serve as a reference for coastal water management and marine ecological management and may be useful for further studies on the simulation and prediction of H. akashiwo blooms, particularly in the ECS.
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21
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Modeling mixoplankton along the biogeochemical gradient of the Southern North Sea. Ecol Modell 2021; 459:109690. [PMID: 34732971 PMCID: PMC8507435 DOI: 10.1016/j.ecolmodel.2021.109690] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 07/27/2021] [Accepted: 07/29/2021] [Indexed: 11/22/2022]
Abstract
The ecological importance of mixoplankton within marine protist communities is slowly being recognized. However, most aquatic ecosystem models do not include formulations to model a complete protist community consisting of phytoplankton, protozooplankton and mixoplankton. We introduce PROTIST, a new module for the aquatic ecosystem modelling software Delft3D-WAQ that can model a protist community consisting of two types of phytoplankton (diatoms and green algae), two types of mixoplankton (constitutive mixoplankton and non-constitutive mixoplankton) and protozooplankton. We employed PROTIST to further explore the hypothesis that the biogeochemical gradient of inorganic nutrient and suspended sediment concentrations drives the observed occurrence of constitutive mixoplankton in the Dutch Southern North Sea. To explore this hypothesis, we used 11 1D-vertical aquatic ecosystem models that mimic the abiotic conditions of 11 routine monitoring locations in the Dutch Southern North Sea. Our models result in plausible trophic compositions across the biogeochemical gradient as compared to in-situ data. A sensitivity analysis showed that the dissolved inorganic phosphate and silica concentrations drive the occurrence of constitutive mixoplankton in the Dutch Southern North Sea. A model to simulate the protist community including mixoplankton is introduced. The model was tested in 1D-V models along a biogeochemical gradient. Modelled mixoplankton are more sensitive to nutrients than to light.
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22
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Multi-Element Composition of Diatom Chaetoceros spp. from Natural Phytoplankton Assemblages of the Russian Arctic Seas. BIOLOGY 2021; 10:biology10101009. [PMID: 34681108 PMCID: PMC8533213 DOI: 10.3390/biology10101009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 09/30/2021] [Accepted: 10/04/2021] [Indexed: 01/29/2023]
Abstract
Simple Summary Despite the long history of studying the elemental composition of phytoplankton and its individual ecological and systematic groups or specific algae species, the global dataset is far from completed. Our original research aims to study the elemental composition of a certain taxonomic group of marine diatoms, whose representatives make a significant contribution to primary production in the Arctic Ocean. The data on the chemical composition of diatom microalgae are discussed concerning their role in the global biogeochemical circulation of elements in the ocean. In particular, the obtained data make a prominent input to the study of the multi-element composition of marine diatom species, namely Chaetoceros spp., inhabiting the shelf seas of the Arctic Ocean. These data may be used as a basis for the cultivation of marine diatom strains for obtaining commercially promising producers of biogenic silica or valuable biological products that can be used as raw materials in the production of feed and nutrition for agriculture and aquaculture. Abstract Data on the elemental composition of the diatom Chaetoceros spp. from natural phytoplankton communities of Arctic marine ecosystems are presented for the first time. Samples were collected during the 69th cruise (22 August–26 September 2017) of the R/V Akademik Mstislav Keldysh in the Kara, Laptev, and East Siberian Seas. The multi-element composition of the diatom microalgae was studied by ICP-AES and ICP-MS methods. The contents of major (Na, Mg, Al, Si, P, S, K and Ca), trace (Li, Be, B, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Mo, Ag, Cd, Sn, Sb, Cs, Ba, Hg, Tl, Pb, Bi, Th and U) and rare earth (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) elements varied greatly, which was probably associated with the peculiarities of the functional state and mineral nutrition of phytoplankton in the autumn period. Biogenic silicon was the dominant component of the chemical composition of Chaetoceros spp., averaging 19.10 ± 0.58% of dry weight (DW). Other significant macronutrients were alkaline (Na and K) and alkaline earth (Ca and Mg) metals as well as biogenic (S and P) and essential (Al and Fe) elements. Their total contents varied from 1.26 to 2.72% DW, averaging 2.07 ± 0.43% DW. The Al:Si ratio for natural assemblages of Chaetoceros spp. of the shelf seas of the Arctic Ocean was 5.8 × 10−3. The total concentrations of trace and rare earth elements on average were 654.42 ± 120.07 and 4.14 ± 1.37 μg g−1 DW, respectively. We summarize the scarce data on the average chemical composition of marine and oceanic phytoplankton and discuss the limitations and approaches of such studies. We conclude on the lack of data and the need for further targeted studies on this issue.
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Huang K, Zhuang Y, Wang Z, Ou L, Cen J, Lu S, Qi Y. Bioavailability of Organic Phosphorus Compounds to the Harmful Dinoflagellate Karenia mikimotoi. Microorganisms 2021; 9:1961. [PMID: 34576855 PMCID: PMC8469735 DOI: 10.3390/microorganisms9091961] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/13/2021] [Accepted: 09/13/2021] [Indexed: 11/16/2022] Open
Abstract
Karenia mikimotoi is one of the most well-known harmful bloom species in temperate coastal waters. The present study investigated the characteristics of alkaline phosphatase (APase) and phosphodiesterase (PDEase) activities in hydrolysis of two phosphomonoesters (adenosine triphosphate (ATP) and ribulose 5-phosphate (R5P)) and a phosphodiester (cyclic adenosine monophosphate (cAMP)) in K. mikimotoi and compared its growth and physiological responses to the different forms of phosphorus substrates. K. mikimotoi produced comparable quantities of APase and PDEase to hydrolyze the organic phosphorus substrates, although hydrolysis of the phosphomonoesters was much faster than that of the phosphodiester. The growth of K. mikimotoi on organic phosphorus substrates was comparable to or better than that on inorganic phosphate. The difference in particulate organic nutrients (carbon, nitrogen, and phosphorus) and hemolytic activity supported different rates of hydrolysis-assimilation of the various organic phosphorus substrates by K. mikimotoi. The hemolytic activities of K. mikimotoi in the presence of organic phosphorus substrates were several times those in the presence of inorganic phosphate during the exponential phase. This suggested the potential important role of organic phosphorus in K. mikimotoi blooms.
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Affiliation(s)
| | | | | | - Linjian Ou
- Research Center of Harmful Algae and Marine Biology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Jinan University, Guangzhou 510632, China; (K.H.); (Y.Z.); (Z.W.); (J.C.); (S.L.); (Y.Q.)
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24
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Müller B, Steinsberger T, Stöckli A, Wüest A. Increasing Carbon-to-Phosphorus Ratio (C:P) from Seston as a Prime Indicator for the Initiation of Lake Reoligotrophication. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:6459-6466. [PMID: 33797885 DOI: 10.1021/acs.est.0c08526] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Decline in total phosphorus (TP) during lake reoligotrophication does not apparently immediately influence carbon assimilation or deep-water oxygen levels. Traditional monitoring and interpretation do not typically consider the amount of organic carbon exported from the productive zone into the hypolimnion as a measure of net ecosystem production. This research investigated the carbon-to-phosphorus ratios of suspended particles in the epilimnion, (C:P)epi, as indicators of changing productivity. We report sestonic C:P ratios, phytoplankton biomass, and hypolimnetic oxygen depletion rates in Lake Hallwil, a lake whose recovery from eutrophic conditions has been documented in 35 years of historic water-monitoring data. This study also interpreted long-term (C:P)epi ratios from reoligotrophication occurring in four other lakes. Lake Hallwil exhibited three distinct phases. (i) The (C:P)epi ratio remained low when TP concentrations did not limit production. (ii) (C:P)epi increased steadily when phytoplankton began optimizing the declining P and biomass remained stable. (iii) Below a critical TP threshold of ∼15 to ∼20 mg P m-3, (C:P)epi remained high and the biomass eventually declined. This analysis showed that the (C:P)epi ratio indicates the reduction of productivity prior to classic indicators such as deep-water oxygen depletion.
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Affiliation(s)
- Beat Müller
- Surface Waters-Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum 6047, Switzerland
| | - Thomas Steinsberger
- Surface Waters-Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum 6047, Switzerland
| | - Arno Stöckli
- Department of Civil Engineering, Transportation and Environment, Canton Argovia, Entfelderstrasse 22, Aarau 5001, Switzerland
| | - Alfred Wüest
- Surface Waters-Research and Management, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum 6047, Switzerland
- Physics of Aquatic Systems Laboratory, Margaretha Kamprad Chair, ENAC-IEE- APHYS, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
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Ustick LJ, Larkin AA, Garcia CA, Garcia NS, Brock ML, Lee JA, Wiseman NA, Moore JK, Martiny AC. Metagenomic analysis reveals global-scale patterns of ocean nutrient limitation. Science 2021; 372:287-291. [DOI: 10.1126/science.abe6301] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 03/01/2021] [Indexed: 12/23/2022]
Abstract
Nutrient supply regulates the activity of phytoplankton, but the global biogeography of nutrient limitation and co-limitation is poorly understood. Prochlorococcus adapt to local environments by gene gains and losses, and we used genomic changes as an indicator of adaptation to nutrient stress. We collected metagenomes from all major ocean regions as part of the Global Ocean Ship-based Hydrographic Investigations Program (Bio-GO-SHIP) and quantified shifts in genes involved in nitrogen, phosphorus, and iron assimilation. We found regional transitions in stress type and severity as well as widespread co-stress. Prochlorococcus stress genes, bottle experiments, and Earth system model predictions were correlated. We propose that the biogeography of multinutrient stress is stoichiometrically linked by controls on nitrogen fixation. Our omics-based description of phytoplankton resource use provides a nuanced and highly resolved description of nutrient stress in the global ocean.
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Affiliation(s)
- Lucas J. Ustick
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA 92697, USA
| | - Alyse A. Larkin
- Department of Earth System Science, University of California Irvine, Irvine, CA 92697, USA
| | - Catherine A. Garcia
- Department of Earth System Science, University of California Irvine, Irvine, CA 92697, USA
| | - Nathan S. Garcia
- Department of Earth System Science, University of California Irvine, Irvine, CA 92697, USA
| | - Melissa L. Brock
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA 92697, USA
| | - Jenna A. Lee
- Department of Earth System Science, University of California Irvine, Irvine, CA 92697, USA
| | - Nicola A. Wiseman
- Department of Earth System Science, University of California Irvine, Irvine, CA 92697, USA
| | - J. Keith Moore
- Department of Earth System Science, University of California Irvine, Irvine, CA 92697, USA
| | - Adam C. Martiny
- Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA 92697, USA
- Department of Earth System Science, University of California Irvine, Irvine, CA 92697, USA
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Rees TAV, Raven JA. The maximum growth rate hypothesis is correct for eukaryotic photosynthetic organisms, but not cyanobacteria. THE NEW PHYTOLOGIST 2021; 230:601-611. [PMID: 33449358 PMCID: PMC8048539 DOI: 10.1111/nph.17190] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 12/23/2020] [Indexed: 05/12/2023]
Abstract
The (maximum) growth rate (µmax ) hypothesis predicts that cellular and tissue phosphorus (P) concentrations should increase with increasing growth rate, and RNA should also increase as most of the P is required to make ribosomes. Using published data, we show that though there is a strong positive relationship between the µmax of all photosynthetic organisms and their P content (% dry weight), leading to a relatively constant P productivity, the relationship with RNA content is more complex. In eukaryotes there is a strong positive relationship between µmax and RNA content expressed as % dry weight, and RNA constitutes a relatively constant 25% of total P. In prokaryotes the rRNA operon copy number is the important determinant of the amount of RNA present in the cell. The amount of phospholipid expressed as % dry weight increases with increasing µmax in microalgae. The relative proportions of each of the five major P-containing constituents is remarkably constant, except that the proportion of RNA is greater and phospholipids smaller in prokaryotic than eukaryotic photosynthetic organisms. The effect of temperature differences between studies was minor. The evidence for and against P-containing constituents other than RNA being involved with ribosome synthesis and functioning is discussed.
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Affiliation(s)
- T. A. V. Rees
- Leigh Marine LaboratoryInstitute of Marine ScienceUniversity of AucklandAuckland1142New Zealand
| | - John A. Raven
- Division of Plant ScienceUniversity of Dundee at the James Hutton InstituteInvergowrie, Dundee,DD2 5DAUK
- Climate Change ClusterFaculty of ScienceUniversity of TechnologySydney, UltimoNSW2007Australia
- School of Biological SciencesUniversity of Western AustraliaCrawleyWA6009Australia
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Müller B, Thoma R, Baumann KBL, Callbeck CM, Schubert CJ. Nitrogen removal processes in lakes of different trophic states from on-site measurements and historic data. AQUATIC SCIENCES 2021; 83:37. [PMID: 33785997 PMCID: PMC7946664 DOI: 10.1007/s00027-021-00795-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
UNLABELLED Freshwater lakes are essential hotspots for the removal of excessive anthropogenic nitrogen (N) loads transported from the land to coastal oceans. The biogeochemical processes responsible for N removal, the corresponding transformation rates and overall removal efficiencies differ between lakes, however, it is unclear what the main controlling factors are. Here, we investigated the factors that moderate the rates of N removal under contrasting trophic states in two lakes located in central Switzerland. In the eutrophic Lake Baldegg and the oligotrophic Lake Sarnen, we specifically examined seasonal sediment porewater chemistry, organic matter sedimentation rates, as well as 33-year of historic water column data. We find that the eutrophic Lake Baldegg, which contributed to the removal of 20 ± 6.6 gN m-2 year-1, effectively removed two-thirds of the total areal N load. In stark contrast, the more oligotrophic Lake Sarnen contributed to 3.2 ± 4.2 gN m-2 year-1, and had removed only one-third of the areal N load. The historic dataset of the eutrophic lake revealed a close linkage between annual loads of dissolved N (DN) and removal rates (NRR = 0.63 × DN load) and a significant correlation of the concentration of bottom water nitrate and removal rates. We further show that the seasonal increase in N removal rates of the eutrophic lake correlated significantly with seasonal oxygen fluxes measured across the water-sediment interface (R2 = 0.75). We suggest that increasing oxygen enhances sediment mineralization and stimulates nitrification, indirectly enhancing denitrification activity. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s00027-021-00795-7.
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Affiliation(s)
- Beat Müller
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
| | - Raoul Thoma
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
| | - Kathrin B. L. Baumann
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
| | - Cameron M. Callbeck
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
| | - Carsten J. Schubert
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
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Inomura K, Deutsch C, Masuda T, Prášil O, Follows MJ. Quantitative models of nitrogen-fixing organisms. Comput Struct Biotechnol J 2020; 18:3905-3924. [PMID: 33335688 PMCID: PMC7733014 DOI: 10.1016/j.csbj.2020.11.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/11/2020] [Accepted: 11/13/2020] [Indexed: 10/26/2022] Open
Abstract
Nitrogen-fixing organisms are of importance to the environment, providing bioavailable nitrogen to the biosphere. Quantitative models have been used to complement the laboratory experiments and in situ measurements, where such evaluations are difficult or costly. Here, we review the current state of the quantitative modeling of nitrogen-fixing organisms and ways to enhance the bridge between theoretical and empirical studies.
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Affiliation(s)
- Keisuke Inomura
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Curtis Deutsch
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Takako Masuda
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, Třeboň, Czech Republic
| | - Ondřej Prášil
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, Třeboň, Czech Republic
| | - Michael J. Follows
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
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29
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Giménez‐Grau P, Felip M, Zufiaurre A, Pla‐Rabès S, Camarero L, Catalan J. Homeostasis and non‐linear shift in the stoichiometry of P‐limited planktonic communities. Ecosphere 2020. [DOI: 10.1002/ecs2.3249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
| | - Marisol Felip
- CREAF Cerdanyola del Vallès Catalonia Spain
- Departament de Biologia Evolutiva Ecologia i Ciències Ambientals. Universitat de Barcelona Barcelona Catalonia Spain
| | | | | | - Lluís Camarero
- Centre d’Estudis Avançats de Blanes (CEAB) CSIC Blanes Catalonia Spain
| | - Jordi Catalan
- CREAF Cerdanyola del Vallès Catalonia Spain
- CSIC Cerdanyola del Vallès Catalonia Spain
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30
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Sandhu SK, Morozov A, Juan L. Exploring the role of spatial and stoichiometric heterogeneity in the top-down control in eutrophic planktonic ecosystems. J Theor Biol 2020; 499:110311. [PMID: 32437709 DOI: 10.1016/j.jtbi.2020.110311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 10/24/2022]
Abstract
Understanding the impact of eutrophication on the dynamics of aquatic food webs, remains a long-term challenge in ecology. Mathematical models generally predict the destabilisation of such webs, under increasing eutrophication levels, with large oscillations of species densities that can result in their extinction. This is at odds with a number of ecological observations that show stable dynamics even for high nutrient loads. The apparent discrepancy between theory and observations is known as the Rosenzweig's 'paradox of enrichment' and various solutions to the problem have been proposed over the years. In this study, we explore the stabilisation of dynamics of a tri-trophic plankton model in a eutrophic environment which occurs as a result of interplay of space heterogeneity, ecological stoichiometry, and food taxis of predators. We build a variety of models of increasing complexity, to explore various scenarios of phytoplankton growth, zooplankton food-dependent vertical movement, and different stoichiometric limitations of zooplankton. We show that the synergy among the vertical gradient in phytoplankton growth, phytoplankton structuring in terms of their stoichiometric ratio, and food-dependent vertical movement of zooplankton, would result in a postponing of destabilisation of eutrophic systems as compared to a well-mixed system. Our approach reveals a high complexity of the bifurcation structure of the system when key model parameters, such as the degree of eutrophication and light shading, are varied. We find coexistence of limit cycles and stable equilibria and that the possibility of multiple attractors in the system can result in hysteresis phenomena when the nutrient load is manipulated. These results are relevant and should be taken into account in lake restoration programs.
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Affiliation(s)
| | - Andrew Morozov
- Department of Mathematics, University of Leicester, UK; Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia.
| | - Lourdes Juan
- Department of Mathematics and Statistics, Texas Tech University, Lubbock, TX, USA
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31
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Sharoni S, Halevy I. Nutrient ratios in marine particulate organic matter are predicted by the population structure of well-adapted phytoplankton. SCIENCE ADVANCES 2020; 6:eaaw9371. [PMID: 32832612 PMCID: PMC7439515 DOI: 10.1126/sciadv.aaw9371] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 06/02/2020] [Indexed: 06/01/2023]
Abstract
A common assumption of a constant nitrogen-to-phosphorus ratio (N:P) of 16:1 in marine particulate organic matter (POM) appears to be invalidated by observations of major spatial variations in N:P. Two main explanations have been proposed. The first attributes the N:P variability to changes in the community composition of well-adapted phytoplankton. The second proposes that variability arises from physiological acclimation involving intracellular adjustments of nutrient allocation under nutrient deficiency. Using a model of phytoplankton physiology, observational datasets, and a review of laboratory culture results, we assess the mechanistic basis of N:P variability. We find that the taxonomic composition of well-adapted phytoplankton best explains observed variations in POM N:P. Furthermore, we show that acclimation to nutrient deficiency may be safely neglected when considering the effects of ecology on POM N:P. These findings provide insight into the controls on global variability in POM composition and average phytoplankton physiological performance in the oceans.
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Affiliation(s)
- Shlomit Sharoni
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
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32
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Fernández-González C, Pérez-Lorenzo M, Pratt N, Moore CM, Bibby TS, Marañón E. Effects of Temperature and Nutrient Supply on Resource Allocation, Photosynthetic Strategy, and Metabolic Rates of Synechococcus sp. JOURNAL OF PHYCOLOGY 2020; 56:818-829. [PMID: 32130730 DOI: 10.1111/jpy.12983] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 02/23/2020] [Indexed: 06/10/2023]
Abstract
Temperature and nutrient supply are key factors that control phytoplankton ecophysiology, but their role is commonly investigated in isolation. Their combined effect on resource allocation, photosynthetic strategy, and metabolism remains poorly understood. To characterize the photosynthetic strategy and resource allocation under different conditions, we analyzed the responses of a marine cyanobacterium (Synechococcus PCC 7002) to multiple combinations of temperature and nutrient supply. We measured the abundance of proteins involved in the dark (RuBisCO, rbcL) and light (Photosystem II, psbA) photosynthetic reactions, the content of chlorophyll a, carbon and nitrogen, and the rates of photosynthesis, respiration, and growth. We found that rbcL and psbA abundance increased with nutrient supply, whereas a temperature-induced increase in psbA occurred only in nutrient-replete treatments. Low temperature and abundant nutrients caused increased RuBisCO abundance, a pattern we observed also in natural phytoplankton assemblages across a wide latitudinal range. Photosynthesis and respiration increased with temperature only under nutrient-sufficient conditions. These results suggest that nutrient supply exerts a stronger effect than temperature upon both photosynthetic protein abundance and metabolic rates in Synechococcus sp. and that the temperature effect on photosynthetic physiology and metabolism is nutrient dependent. The preferential resource allocation into the light instead of the dark reactions of photosynthesis as temperature rises is likely related to the different temperature dependence of dark-reaction enzymatic rates versus photochemistry. These findings contribute to our understanding of the strategies for photosynthetic energy allocation in phytoplankton inhabiting contrasting environments.
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Affiliation(s)
| | - María Pérez-Lorenzo
- Department of Ecology and Animal Biology, Universidade de Vigo, 36310, Vigo, Spain
| | - Nicola Pratt
- Ocean and Earth Science, University of Southampton, SO14 3ZH, Southampton, UK
| | - C Mark Moore
- Ocean and Earth Science, University of Southampton, SO14 3ZH, Southampton, UK
| | - Thomas S Bibby
- Ocean and Earth Science, University of Southampton, SO14 3ZH, Southampton, UK
| | - Emilio Marañón
- Department of Ecology and Animal Biology, Universidade de Vigo, 36310, Vigo, Spain
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33
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Garcia CA, Hagstrom GI, Larkin AA, Ustick LJ, Levin SA, Lomas MW, Martiny AC. Linking regional shifts in microbial genome adaptation with surface ocean biogeochemistry. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190254. [PMID: 32200740 PMCID: PMC7133529 DOI: 10.1098/rstb.2019.0254] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2020] [Indexed: 01/09/2023] Open
Abstract
Linking 'omics measurements with biogeochemical cycles is a widespread challenge in microbial community ecology. Here, we propose applying genomic adaptation as 'biosensors' for microbial investments to overcome nutrient stress. We then integrate this genomic information with a trait-based model to predict regional shifts in the elemental composition of marine plankton communities. We evaluated this approach using metagenomic and particulate organic matter samples from the Atlantic, Indian and Pacific Oceans. We find that our genome-based trait model significantly improves our prediction of particulate C : P (carbon : phosphorus) across ocean regions. Furthermore, we detect previously unrecognized ocean areas of iron, nitrogen and phosphorus stress. In many ecosystems, it can be very challenging to quantify microbial stress. Thus, a carefully calibrated genomic approach could become a widespread tool for understanding microbial responses to environmental changes and the biogeochemical outcomes. This article is part of the theme issue 'Conceptual challenges in microbial community ecology'.
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Affiliation(s)
- Catherine A. Garcia
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
| | - George I. Hagstrom
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - Alyse A. Larkin
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
| | - Lucas J. Ustick
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA 92697, USA
| | - Simon A. Levin
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - Michael W. Lomas
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME 04544, USA
| | - Adam C. Martiny
- Department of Earth System Science, University of California, Irvine, CA 92697, USA
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA 92697, USA
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34
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Omta AW, Talmy D, Inomura K, Irwin AJ, Finkel ZV, Sher D, Liefer JD, Follows MJ. Quantifying nutrient throughput and DOM production by algae in continuous culture. J Theor Biol 2020; 494:110214. [PMID: 32142805 DOI: 10.1016/j.jtbi.2020.110214] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 11/07/2019] [Accepted: 02/24/2020] [Indexed: 01/04/2023]
Abstract
Freshwater and marine algae can balance nutrient demand and availability by regulating uptake, accumulation and exudation. To obtain insight into these processes under nitrogen (N) and phosphorus (P) limitation, we reanalyze published data from continuous cultures of the chlorophyte Selenastrum minutum. Based on mass budgets, we argue that much of the non-limiting N and P had passed through the organisms and was present as dissolved organic phosphorus or nitrogen (DOP or DON). We construct a model that describes the production of biomass and dissolved organic matter (DOM) as a function of the growth rate. A fit of this model against the chemostat data suggests a high turnover of the non-limiting N and P: at the highest growth rates, N and P atoms spent on average only about 3 h inside an organism, before they were exuded as DON and DOP, respectively. This DOM exudation can explain the observed trends in the algal stoichiometric ratios as a function of the dilution rate. We discuss independent evidence from isotope experiments for this apparently wasteful behavior and we suggest experiments to quantify and characterize DON and DOP exudation further.
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Affiliation(s)
- A W Omta
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States.
| | - D Talmy
- Department of Microbiology, University of Tennessee, 1311 Cumberland Avenue, Knoxville, TN 37916, United States.
| | - K Inomura
- School of Oceanography, University of Washington, 1492 NE Boat Street, Seattle, WA 98105, United States.
| | - A J Irwin
- Department of Mathematics and Statistics, Dalhousie University, 6316 Coburg Road, Halifax, NS B3H 4R2, Canada.
| | - Z V Finkel
- Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax, NS B3H 4R2, Canada.
| | - D Sher
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, 199 Aba Khoushy Avenue, Mount Carmel 3498838, Haifa, Israel.
| | - J D Liefer
- Department of Biology, Mount Allison University, 63B York Street, Sackville, NB E4L 1G7, Canada.
| | - M J Follows
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States.
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35
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Reinhard CT, Planavsky NJ, Ward BA, Love GD, Le Hir G, Ridgwell A. The impact of marine nutrient abundance on early eukaryotic ecosystems. GEOBIOLOGY 2020; 18:139-151. [PMID: 32065509 DOI: 10.1111/gbi.12384] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 11/05/2019] [Indexed: 06/10/2023]
Abstract
The rise of eukaryotes to ecological prominence represents one of the most dramatic shifts in the history of Earth's biosphere. However, there is an enigmatic temporal lag between the emergence of eukaryotic organisms in the fossil record and their much later ecological expansion. In parallel, there is evidence for a secular increase in the availability of the key macronutrient phosphorus (P) in Earth's oceans. Here, we use an Earth system model equipped with a size-structured marine ecosystem to explore relationships between plankton size, trophic complexity, and the availability of marine nutrients. We find a strong dependence of planktonic ecosystem structure on ocean nutrient abundance, with a larger ocean nutrient inventory leading to greater overall biomass, broader size spectra, and increasing abundance of large Zooplankton. If existing estimates of Proterozoic marine nutrient levels are correct, our results suggest that increases in the ecological impact of eukaryotic algae and trophic complexity in eukaryotic ecosystems were directly linked to restructuring of the global P cycle associated with the protracted rise of surface oxygen levels. Our results thus suggest an indirect but potentially important mechanism by which ocean oxygenation may have acted to shape marine ecological function during late Proterozoic time.
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Affiliation(s)
- Christopher T Reinhard
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
| | - Noah J Planavsky
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
- Department of Geology and Geophysics, Yale University, New Haven, Connecticut
| | - Ben A Ward
- Ocean and Earth Science, University of Southampton, Southampton, UK
| | - Gordon D Love
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
- Department of Earth and Planetary Sciences, University of California, Riverside, California
| | | | - Andy Ridgwell
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
- Department of Earth and Planetary Sciences, University of California, Riverside, California
- School of Geographical Sciences, University of Bristol, Bristol, UK
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36
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Inomura K, Omta AW, Talmy D, Bragg J, Deutsch C, Follows MJ. A Mechanistic Model of Macromolecular Allocation, Elemental Stoichiometry, and Growth Rate in Phytoplankton. Front Microbiol 2020; 11:86. [PMID: 32256456 PMCID: PMC7093025 DOI: 10.3389/fmicb.2020.00086] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 01/15/2020] [Indexed: 01/09/2023] Open
Abstract
We present a model of the growth rate and elemental stoichiometry of phytoplankton as a function of resource allocation between and within broad macromolecular pools under a variety of resource supply conditions. The model is based on four, empirically-supported, cornerstone assumptions: that there is a saturating relationship between light and photosynthesis, a linear relationship between RNA/protein and growth rate, a linear relationship between biosynthetic proteins and growth rate, and a constant macromolecular composition of the light-harvesting machinery. We combine these assumptions with statements of conservation of carbon, nitrogen, phosphorus, and energy. The model can be solved algebraically for steady state conditions and constrained with data on elemental stoichiometry from published laboratory chemostat studies. It interprets the relationships between macromolecular and elemental stoichiometry and also provides quantitative predictions of the maximum growth rate at given light intensity and nutrient supply rates. The model is compatible with data sets from several laboratory studies characterizing both prokaryotic and eukaryotic phytoplankton from marine and freshwater environments. It is conceptually simple, yet mechanistic and quantitative. Here, the model is constrained only by elemental stoichiometry, but makes predictions about allocation to measurable macromolecular pools, which could be tested in the laboratory.
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Affiliation(s)
- Keisuke Inomura
- School of Oceanography, University of Washington, Seattle, WA, United States
| | - Anne Willem Omta
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - David Talmy
- Department of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Jason Bragg
- National Herbarium of New South Wales, The Royal Botanic Gardens and Domain Trust, Sydney, NSW, Australia
| | - Curtis Deutsch
- School of Oceanography, University of Washington, Seattle, WA, United States
| | - Michael J. Follows
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United States
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37
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D'Alelio D, Rampone S, Cusano LM, Morfino V, Russo L, Sanseverino N, Cloern JE, Lomas MW. Machine learning identifies a strong association between warming and reduced primary productivity in an oligotrophic ocean gyre. Sci Rep 2020; 10:3287. [PMID: 32098970 PMCID: PMC7042350 DOI: 10.1038/s41598-020-59989-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 02/06/2020] [Indexed: 12/20/2022] Open
Abstract
Phytoplankton play key roles in the oceans by regulating global biogeochemical cycles and production in marine food webs. Global warming is thought to affect phytoplankton production both directly, by impacting their photosynthetic metabolism, and indirectly by modifying the physical environment in which they grow. In this respect, the Bermuda Atlantic Time-series Study (BATS) in the Sargasso Sea (North Atlantic gyre) provides a unique opportunity to explore effects of warming on phytoplankton production across the vast oligotrophic ocean regions because it is one of the few multidecadal records of measured net primary productivity (NPP). We analysed the time series of phytoplankton primary productivity at BATS site using machine learning techniques (ML) to show that increased water temperature over a 27-year period (1990–2016), and the consequent weakening of vertical mixing in the upper ocean, induced a negative feedback on phytoplankton productivity by reducing the availability of essential resources, nitrogen and light. The unbalanced availability of these resources with warming, coupled with ecological changes at the community level, is expected to intensify the oligotrophic state of open-ocean regions that are far from land-based nutrient sources.
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Affiliation(s)
- Domenico D'Alelio
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, I-80121, Naples, Italy.
| | - Salvatore Rampone
- Università degli Studi del Sannio, Via Delle Puglie 76, I-82100, Benevento, Italy
| | - Luigi Maria Cusano
- Università degli Studi del Sannio, Via Delle Puglie 76, I-82100, Benevento, Italy
| | - Valerio Morfino
- Università degli Studi del Sannio, Via Delle Puglie 76, I-82100, Benevento, Italy
| | - Luca Russo
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, I-80121, Naples, Italy
| | - Nadia Sanseverino
- Università degli Studi del Sannio, Via Delle Puglie 76, I-82100, Benevento, Italy
| | - James E Cloern
- United States Geological Survey (emeritus), Menlo Park, CA, USA
| | - Michael W Lomas
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, USA.
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38
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Weisse T, Moser M. Light affects picocyanobacterial grazing and growth response of the mixotrophic flagellate Poterioochromonas malhamensis. J Microbiol 2020; 58:268-278. [PMID: 31989545 DOI: 10.1007/s12275-020-9567-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/19/2019] [Accepted: 12/19/2019] [Indexed: 11/28/2022]
Abstract
We measured the grazing and growth response of the mixotrophic chrysomonad flagellate Poterioochromonas malhamensis on four closely related picocyanobacterial strains isolated from subalpine lakes in central Europe. The picocyanobacteria represented different pigment types (phycoerythrin-rich, PE, and phycocyanin-rich, PC) and phylogenetic clusters. The grazing experiments were conducted with laboratory cultures acclimated to 10 µmol photon/m2/sec (low light, LL) and 100 µmol photon/m2/sec (moderate light, ML), either in the dark or at four different irradiances ranging from low (6 µmol photon/m2/sec) to high (1,500 µmol photon/m2/sec) light intensity. Poterioochromonas malhamensis preferred the larger, green PC-rich picocyanobacteria to the smaller, red PE-rich picocyanobacterial, and heterotrophic bacteria. The feeding and growth rates of P. malhamensis were sensitive to the actual light conditions during the experiments; the flagellate performed relatively better in the dark and at LL conditions than at high light intensity. In summary, our results found strain-specific ingestion and growth rates of the flagellate; an effect of the preculturing conditions, and, unexpectedly, a direct adverse effect of high light levels. We conclude that this flagellate may avoid exposure to high surface light intensities commonly encountered in temperate lakes during the summer.
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Affiliation(s)
- Thomas Weisse
- University of Innsbruck, Research Department for Limnology, Mondseestr. 9, A-5310, Mondsee, Austria.
| | - Michael Moser
- University of Innsbruck, Research Department for Limnology, Mondseestr. 9, A-5310, Mondsee, Austria
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39
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Zimmerman AE, Howard-Varona C, Needham DM, John SG, Worden AZ, Sullivan MB, Waldbauer JR, Coleman ML. Metabolic and biogeochemical consequences of viral infection in aquatic ecosystems. Nat Rev Microbiol 2019; 18:21-34. [PMID: 31690825 DOI: 10.1038/s41579-019-0270-x] [Citation(s) in RCA: 158] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2019] [Indexed: 12/23/2022]
Abstract
Ecosystems are controlled by 'bottom-up' (resources) and 'top-down' (predation) forces. Viral infection is now recognized as a ubiquitous top-down control of microbial growth across ecosystems but, at the same time, cell death by viral predation influences, and is influenced by, resource availability. In this Review, we discuss recent advances in understanding the biogeochemical impact of viruses, focusing on how metabolic reprogramming of host cells during lytic viral infection alters the flow of energy and nutrients in aquatic ecosystems. Our synthesis revealed several emerging themes. First, viral infection transforms host metabolism, in part through virus-encoded metabolic genes; the functions performed by these genes appear to alleviate energetic and biosynthetic bottlenecks to viral production. Second, viral infection depends on the physiological state of the host cell and on environmental conditions, which are challenging to replicate in the laboratory. Last, metabolic reprogramming of infected cells and viral lysis alter nutrient cycling and carbon export in the oceans, although the net impacts remain uncertain. This Review highlights the need for understanding viral infection dynamics in realistic physiological and environmental contexts to better predict their biogeochemical consequences.
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Affiliation(s)
- Amy E Zimmerman
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | | | - David M Needham
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA
| | - Seth G John
- Department of Earth Science, University of Southern California, Los Angeles, CA, USA
| | - Alexandra Z Worden
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA.,Ocean EcoSystems Biology Unit, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
| | - Matthew B Sullivan
- Department of Microbiology, Ohio State University, Columbus, OH, USA.,Department of Civil, Environmental and Geodetic Engineering, Ohio State University, Columbus, OH, USA
| | - Jacob R Waldbauer
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | - Maureen L Coleman
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA.
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40
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Tagliabue A, Bowie AR, DeVries T, Ellwood MJ, Landing WM, Milne A, Ohnemus DC, Twining BS, Boyd PW. The interplay between regeneration and scavenging fluxes drives ocean iron cycling. Nat Commun 2019; 10:4960. [PMID: 31673108 PMCID: PMC6823497 DOI: 10.1038/s41467-019-12775-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 09/30/2019] [Indexed: 01/18/2023] Open
Abstract
Despite recent advances in observational data coverage, quantitative constraints on how different physical and biogeochemical processes shape dissolved iron distributions remain elusive, lowering confidence in future projections for iron-limited regions. Here we show that dissolved iron is cycled rapidly in Pacific mode and intermediate water and accumulates at a rate controlled by the strongly opposing fluxes of regeneration and scavenging. Combining new data sets within a watermass framework shows that the multidecadal dissolved iron accumulation is much lower than expected from a meta-analysis of iron regeneration fluxes. This mismatch can only be reconciled by invoking significant rates of iron removal to balance iron regeneration, which imply generation of authigenic particulate iron pools. Consequently, rapid internal cycling of iron, rather than its physical transport, is the main control on observed iron stocks within intermediate waters globally and upper ocean iron limitation will be strongly sensitive to subtle changes to the internal cycling balance. Iron is crucial for marine photosynthesis, but observational constraints on the magnitude of key iron cycle processes are lacking. Here the authors use a range of observational data sets to demonstrate that the balance between iron re-supply and removal in the subsurface controls upper ocean iron limitation.
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Affiliation(s)
| | - Andrew R Bowie
- Institute for Marine and Antarctic Studies and Antarctic Climate and Ecosystems CRC, University of Tasmania, Hobsart, TAS, Australia
| | - Timothy DeVries
- University of California Santa Barbara, Santa Barbara, CA, USA
| | - Michael J Ellwood
- Research School of Earth Sciences, Australian National University, Canberra, ACT, Australia
| | | | - Angela Milne
- Florida State University, Tallahassee, FL, USA.,University of Plymouth, Plymouth, UK
| | | | | | - Philip W Boyd
- Institute for Marine and Antarctic Studies and Antarctic Climate and Ecosystems CRC, University of Tasmania, Hobsart, TAS, Australia
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41
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Faithfull C, Goetze E. Copepod nauplii use phosphorus from bacteria, creating a short circuit in the microbial loop. Ecol Lett 2019; 22:1462-1471. [PMID: 31270952 DOI: 10.1111/ele.13332] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/11/2019] [Accepted: 06/05/2019] [Indexed: 11/30/2022]
Abstract
In subtropical oceans phytoplankton carbon: phosphorus (C : P) ratios are high, and these ratios are predicted to increase further with rising ocean temperatures and stratification. Prey stoichiometry may pose a problem for copepod zooplankton nauplii, which have high phosphorus demands due to rapid growth. We hypothesised that nauplii meet this demand by consuming bacteria. Naupliar bacterial and phytoplankton carbon and phosphorus ingestion, assimilation and incorporation were traced using 33 P and 14 C radioisotopes. Bacterial carbon was incorporated four times less efficiently into biomass than phytoplankton carbon. In contrast, bacterial and phytoplankton phosphorus were incorporated at similar efficiencies, and bacteria could meet a substantial amount of naupliar phosphorus requirements. As parts of the ocean become more oligotrophic, bacteria could help sustain naupliar growth and survival under suboptimal stoichiometric conditions. Thus, nauplii may be a shortcut for phosphorus from the microbial loop to the classical food web.
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Affiliation(s)
- Carolyn Faithfull
- Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden.,Department of Oceanography, University of Hawaii at Manoa, Honolulu, Hawaii
| | - Erica Goetze
- Department of Oceanography, University of Hawaii at Manoa, Honolulu, Hawaii
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42
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Zhang C, Yao X, Chen Y, Chu Q, Yu Y, Shi J, Gao H. Variations in the phytoplankton community due to dust additions in eutrophication, LNLC and HNLC oceanic zones. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 669:282-293. [PMID: 30878935 DOI: 10.1016/j.scitotenv.2019.02.068] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/04/2019] [Accepted: 02/04/2019] [Indexed: 06/09/2023]
Abstract
Dust deposition can bring nutrients and trace elements to the upper ocean and affect phytoplankton growth and community structure. We conducted a comparative study using on-board microcosm experiments amended with varying amounts of dust (0.2, 1, and 2 mg L-1) in the East China Sea (eutrophic zone), the subtropical gyre (low-nutrient and low-chlorophyll zone, LNLC), and the Kuroshio-Oyashio transition region (high-nutrient and low-chlorophyll zone, HNLC) of the Northwest Pacific Ocean. The additions of dust supplied a considerable amount of nitrogen (N) and negligible phosphorus (P) relative to the seawater collected for incubation experiments (baseline), contributing to increases in Chlorophyll a with increasing dust additions. Significant linear correlations were observed between the net growth rates of larger cells (i.e., micro-size: >20 μm and nano-size: 2-20 μm) and available N (sum of baseline and added N) at each zone, demonstrating that phytoplankton size structure shifts towards larger cells with the increasing dust additions. In the experiments conducted in LNLC and HNLC zones, micro-sized phytoplankton (primarily consisting of diatoms) benefited most from dust additions. In the experiments conducted in eutrophic zone, however, the primary beneficiary was the nano-sized phytoplankton (primarily consisting of dinoflagellates). When a time lag of one day in relative abundance of diatoms (RAD, the abundance of diatoms divided by the sum of diatoms and dinoflagellates) relative to the N:P ratio was considered, we found the RAD increased substantially with increases in the N:P ratio until the ratio approached the Redfield ratio (N:P = 16:1), and then the RAD decreased gradually as the N:P ratio increased. This was ascribed to the lower sensitivity of dinoflagellates to nutrient shortage, relative to diatoms. Overall, our results suggested that the overwhelming input of N relative to P by dust deposition might cause significant ecological impacts by altering the N:P ratio of varying trophic seawaters.
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Affiliation(s)
- Chao Zhang
- Key Laboratory of Marine Environment and Ecology, Ministry of Education of China, Ocean University of China, Qingdao 266100, China
| | - Xiaohong Yao
- Key Laboratory of Marine Environment and Ecology, Ministry of Education of China, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Sciences, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
| | - Ying Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention, Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Qiang Chu
- Key Laboratory of Marine Environment and Ecology, Ministry of Education of China, Ocean University of China, Qingdao 266100, China; Laboratory of Environmental Protection in Water Transport Engineering, Tianjin Research Institute for Water Transport Engineering, Ministry of Transport, Tianjin, China
| | - Yang Yu
- Key Laboratory of Marine Environment and Ecology, Ministry of Education of China, Ocean University of China, Qingdao 266100, China
| | - Jinhui Shi
- Key Laboratory of Marine Environment and Ecology, Ministry of Education of China, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Sciences, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
| | - Huiwang Gao
- Key Laboratory of Marine Environment and Ecology, Ministry of Education of China, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Sciences, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
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43
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Wagner H, Jebsen C, Wilhelm C. Monitoring cellular C:N ratio in phytoplankton by means of FTIR-spectroscopy. JOURNAL OF PHYCOLOGY 2019; 55:543-551. [PMID: 30893470 DOI: 10.1111/jpy.12858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 01/04/2019] [Indexed: 06/09/2023]
Abstract
Statistical growth rate modelling can be applied in a variety of ecological and biotechnological applications. Such models are frequently based on Monod or Droop equations and, especially for the latter, require reliable determination of model input parameters such as C:N quotas. Besides growth rate modelling, a C:N quota quantification can be useful for monitoring and interpretation of physiological acclimation to abiotic and biotic disturbances (e.g., nutrient limitations). However, as high throughput C:N quota determination is difficult to perform, alternatives need to be established. Fourier-transformed infrared (FTIR) spectroscopy is used to analyze a variety of biochemical, chemical, and physiological parameters in phytoplankton. Hence, a quantification of the C:N quota should also be feasible. Therefore, using FTIR spectroscopy, six phytoplankton species from among different phylogenetic groups have been analyzed to determine the effect of nutrient limitation on C:N quota patterns. The typical species-specific response to increasing nitrogen limitation was an increase in the C:N quota. Irrespective of this species specificity, we were able to develop a reliable multi-species C:N quota prediction model based on FTIR spectroscopy using the partial least square regression (PLSR) algorithm. Our data demonstrate that the PLSR approach is more robust in C:N quota quantification (R2 = 0.93) than linear correlation of C:N quota versus growth rate (R2 ranges from 0.74 to 0.86) or biochemical information based on FTIR spectra (R2 ranges from 0.82 to 0.89). This accurate prediction of C:N values may support high throughput measurements in a broad range of future approaches.
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Affiliation(s)
- Heiko Wagner
- Department of Plant Physiology, Institute of Biology, Leipzig University, Johannisallee 21-23, D-04103, Leipzig, Germany
| | - Christian Jebsen
- Department of Plant Physiology, Institute of Biology, Leipzig University, Johannisallee 21-23, D-04103, Leipzig, Germany
| | - Christian Wilhelm
- Department of Plant Physiology, Institute of Biology, Leipzig University, Johannisallee 21-23, D-04103, Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, D-04103, Leipzig, Germany
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44
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Manzella M, Geiss R, Hall EK. Evaluating the stoichiometric trait distributions of cultured bacterial populations and uncultured microbial communities. Environ Microbiol 2019; 21:3613-3626. [PMID: 31090973 DOI: 10.1111/1462-2920.14684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
We measured the stoichiometric trait distribution of cultured freshwater bacterial populations under different resource conditions and compared them to natural microbial communities sampled from three lakes. Trait distributions showed population differences among growth phases and community differences among lakes that would have been masked by only reporting the mean biomass value. The stoichiometric trait distribution of the environmental isolates changed with P availability, growth phase and genotype, with P availability having the strongest effect. The distribution of biomass ratios within each isolate growth experiment were the most constrained during the stages of rapid growth and commonly had unimodal distributions. In contrast to the population distributions, the distribution of N:P and C:P for a similar number of cells from each of the lake communities had narrower stoichiometric distributions and more commonly exhibited multiple modes. © 2019 Society for Applied Microbiology and John Wiley & Sons Ltd.
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Affiliation(s)
- Michael Manzella
- Department of Ecosystem Science and Sustainability, Colorado State University, Fort Collins, CO, 80523, USA.,Department of Biology, Indiana University, Bloomington, IN, 47405, USA
| | - Roy Geiss
- Central Instrument Facility, Department of Chemistry, Colorado State University, Fort Collins, CO, 80523, USA
| | - Ed K Hall
- Department of Ecosystem Science and Sustainability, Colorado State University, Fort Collins, CO, 80523, USA.,Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, 80523, USA
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45
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Exposure of the Host-Associated Microbiome to Nutrient-Rich Conditions May Lead to Dysbiosis and Disease Development-an Evolutionary Perspective. mBio 2019; 10:mBio.00355-19. [PMID: 31088923 PMCID: PMC6520449 DOI: 10.1128/mbio.00355-19] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Inflammatory diseases, such as inflammatory bowel diseases, are dramatically increasing worldwide, but an understanding of the underlying factors is lacking. We here present an ecoevolutionary perspective on the emergence of inflammatory diseases. Inflammatory diseases, such as inflammatory bowel diseases, are dramatically increasing worldwide, but an understanding of the underlying factors is lacking. We here present an ecoevolutionary perspective on the emergence of inflammatory diseases. We propose that adaptation has led to fine-tuned host-microbe interactions, which are maintained by secreted host metabolites nourishing the associated microbes. A constant elevation of nutrients in the gut environment leads to an increased activity and changed functionality of the microbiota, thus severely disturbing host-microbe interactions and leading to dysbiosis and disease development. In the past, starvation and pathogen infections, causing diarrhea, were common incidences that reset the gut bacterial community to its “human-specific-baseline.” However, these natural clearing mechanisms have been virtually eradicated in developed countries, allowing a constant uncontrolled growth of bacteria. This leads to an increase of bacterial products that stimulate the immune system and ultimately might initiate inflammatory reactions.
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46
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Garcia CA, Baer SE, Garcia NS, Rauschenberg S, Twining BS, Lomas MW, Martiny AC. Nutrient supply controls particulate elemental concentrations and ratios in the low latitude eastern Indian Ocean. Nat Commun 2018; 9:4868. [PMID: 30451846 PMCID: PMC6242840 DOI: 10.1038/s41467-018-06892-w] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 09/14/2018] [Indexed: 11/17/2022] Open
Abstract
Variation in ocean C:N:P of particulate organic matter (POM) has led to competing hypotheses for the underlying drivers. Each hypothesis predicts C:N:P equally well due to regional co-variance in environmental conditions and biodiversity. The Indian Ocean offers a unique positive temperature and nutrient supply relationship to test these hypotheses. Here we show how elemental concentrations and ratios vary over daily and regional scales. POM concentrations were lowest in the southern gyre, elevated across the equator, and peaked in the Bay of Bengal. Elemental ratios were highest in the gyre, but approached Redfield proportions northwards. As Prochlorococcus dominated the phytoplankton community, biodiversity changes could not explain the elemental variation. Instead, our data supports the nutrient supply hypothesis. Finally, gyre dissolved iron concentrations suggest extensive iron stress, leading to depressed ratios compared to other gyres. We propose a model whereby differences in iron supply and N2-fixation influence C:N:P levels across ocean gyres.
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Affiliation(s)
- Catherine A Garcia
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92617, USA
| | - Steven E Baer
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, 04544, USA
- Maine Maritime Academy, Castine, ME, 04420, USA
| | - Nathan S Garcia
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92617, USA
| | - Sara Rauschenberg
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, 04544, USA
| | | | - Michael W Lomas
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, 04544, USA
| | - Adam C Martiny
- Department of Earth System Science, University of California at Irvine, Irvine, CA, 92617, USA.
- Department of Ecology and Evolution, University of California at Irvine, Irvine, CA, 92617, USA.
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47
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Verbeek L, Gall A, Hillebrand H, Striebel M. Warming and oligotrophication cause shifts in freshwater phytoplankton communities. GLOBAL CHANGE BIOLOGY 2018; 24:4532-4543. [PMID: 29856108 DOI: 10.1111/gcb.14337] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 05/02/2018] [Accepted: 05/11/2018] [Indexed: 05/06/2023]
Abstract
While there is a lot of data on interactive effects of eutrophication and warming, to date, we lack data to generate reliable predictions concerning possible effects of nutrient decrease and temperature increase on community composition and functional responses. In recent years, a wide-ranging trend of nutrient decrease (re-oligotrophication) was reported for freshwater systems. Small lakes and ponds, in particular, show rapid responses to anthropogenic pressures and became model systems to investigate single as well as synergistic effects of warming and fertilization in situ and in experiments. Therefore, we set up an experiment to investigate the single as well as the interactive effects of nutrient reduction and gradual temperature increase on a natural freshwater phytoplankton community, using an experimental indoor mesocosm setup. Biomass production initially increased with warming but decreased with nutrient depletion. If nutrient supply was constant, biomass increased further, especially under warming conditions. Under low nutrient supply, we found a sharp transition from initially positive effects of warming to negative effects when resources became scarce. Warming reduced phytoplankton richness and evenness, whereas nutrient reduction at ambient temperature had positive effects on diversity. Our results indicate that temperature effects on freshwater systems will be altered by nutrient availability. These interactive effects of energy increase and resource decrease have major impacts on biodiversity and ecosystem function and thus need to be considered in environmental management plans.
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Affiliation(s)
- Laura Verbeek
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Wilhelmshaven, Germany
| | - Andrea Gall
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Wilhelmshaven, Germany
| | - Helmut Hillebrand
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Wilhelmshaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, Germany
| | - Maren Striebel
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Wilhelmshaven, Germany
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48
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Van de Waal DB, Elser JJ, Martiny AC, Sterner RW, Cotner JB. Editorial: Progress in Ecological Stoichiometry. Front Microbiol 2018; 9:1957. [PMID: 30233506 PMCID: PMC6134043 DOI: 10.3389/fmicb.2018.01957] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 08/02/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Dedmer B Van de Waal
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, Netherlands
| | - James J Elser
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
- Flathead Lake Biological Station, University of Montana, Polson, MT, United States
| | - Adam C Martiny
- Department of Earth System Science, University of California, Irvine, Irvine, CA, United States
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States
| | - Robert W Sterner
- Large Lakes Observatory, University of Minnesota Duluth, Duluth, MN, United States
| | - James B Cotner
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN, United States
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49
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Linzner KA, Kent AG, Martiny AC. Evolutionary Pathway Determines the Stoichiometric Response of Escherichia coli Adapted to High Temperature. Front Ecol Evol 2018. [DOI: 10.3389/fevo.2017.00173] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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50
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Van de Waal DB, Elser JJ, Martiny AC, Sterner RW, Cotner JB. Editorial: Progress in Ecological Stoichiometry. Front Microbiol 2018. [PMID: 30233506 DOI: 10.3389/978-2-88945-621-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023] Open
Affiliation(s)
- Dedmer B Van de Waal
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, Netherlands
| | - James J Elser
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
- Flathead Lake Biological Station, University of Montana, Polson, MT, United States
| | - Adam C Martiny
- Department of Earth System Science, University of California, Irvine, Irvine, CA, United States
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States
| | - Robert W Sterner
- Large Lakes Observatory, University of Minnesota Duluth, Duluth, MN, United States
| | - James B Cotner
- Department of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN, United States
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