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Harikrishnan T, Sivakumar P, Sivakumar S, Arumugam S, Raman T, Singaram G, Thangavelu M, Kim W, Muthusamy G. Effect of microfibers induced toxicity in marine sedentary polychaete Hydroides elegans: Insight from embryogenesis axis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167579. [PMID: 37797759 DOI: 10.1016/j.scitotenv.2023.167579] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/21/2023] [Accepted: 10/02/2023] [Indexed: 10/07/2023]
Abstract
Presence of surgical face masks in the environment are more than ever before after the COVID-19 pandemic, and it poses a newer threat to aquatic habitats around the world due to microfibers (MFs) and other contaminants that get discharged when these masks deteriorate. The mechanism behind the developmental toxicity of MFs, especially released from surgical masks, on the early life stages of aquatic organisms are not well understood. Toxicity test were developed to examine the effects of MFs released from surgical facemask upon deterioration using the early gametes and early life stages of marine sedentary polychaete Hydroides elegans. For MFs release, cut pieces of face masks were allowed to degrade in seawater for different time points (1 day, 30 days and 120 days) after which the fibers were obtained for further toxicity studies. The gametes of H. elegans were exposed to the MFs (length < 20 μm) separately for 20 min at a concentration of 50 MFs/ml before fertilization. In addition, we also analyzed the experimental samples for heavy metals and organic substances released from face masks. Our findings demonstrated that gametes exposed to MFs affected the percentage of successful development, considerably slowed down the mitotic cell division and significantly postponed the time of larval hatching and also produced an adverse effect during embryogenesis. When the sperm were exposed fertilization rate was decreased drastically, whereas when the eggs were exposed to MFs fertilization was not inhibited but a delay in early embryonic development observed. In addition the release of heavy metals and other volatile organics from the degrading face masks could also contribute to overall toxicity of these materials in environment. Our study thus shows that inappropriately discarded face masks and MFs and other pollutants released from such face masks could pose long-term hazard to coastal ecosystems.
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Affiliation(s)
- Thilagam Harikrishnan
- Postgraduate and Research Department of Zoology, Pachaiyappa's College for Men, Chennai 600 030, India.
| | - Priya Sivakumar
- Postgraduate and Research Department of Zoology, Pachaiyappa's College for Men, Chennai 600 030, India
| | - Swetha Sivakumar
- Department of Biotechnology, Prince Venkateswara Arts and Science College, Chennai 600 073, India
| | - Sriramajayam Arumugam
- Postgraduate and Research Department of Zoology, Pachaiyappa's College for Men, Chennai 600 030, India
| | - Thiagarajan Raman
- Department of Zoology, Ramakrishna Mission Vivekananda College (Autonomous), Chennai 600 004, India
| | - Gopalakrishnan Singaram
- Department of Biotechnology, Dwaraka Doss Goverdhan Doss Vaishnav College, Chennai 600106, India
| | - Muthukumar Thangavelu
- Dept BIN Convergence Tech, Dept PolymerNano Sci & Tech, Jeonbuk National University, 567 Baekje-dearo, Deokjin, Jeonju, Jeollabuk-do 54896, Republic of Korea
| | - Woong Kim
- Department of Environmental Engineering, Kyungpook National University, Daehak-ro, Buk-gu, Daegu 41566, South Korea
| | - Govarthanan Muthusamy
- Department of Environmental Engineering, Kyungpook National University, Daehak-ro, Buk-gu, Daegu 41566, South Korea; Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai 600 077, India.
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Leung JYS, Zhang S, Connell SD. Is Ocean Acidification Really a Threat to Marine Calcifiers? A Systematic Review and Meta-Analysis of 980+ Studies Spanning Two Decades. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2107407. [PMID: 35934837 DOI: 10.1002/smll.202107407] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 06/24/2022] [Indexed: 06/15/2023]
Abstract
Ocean acidification is considered detrimental to marine calcifiers, but mounting contradictory evidence suggests a need to revisit this concept. This systematic review and meta-analysis aim to critically re-evaluate the prevailing paradigm of negative effects of ocean acidification on calcifiers. Based on 5153 observations from 985 studies, many calcifiers (e.g., echinoderms, crustaceans, and cephalopods) are found to be tolerant to near-future ocean acidification (pH ≈ 7.8 by the year 2100), but coccolithophores, calcifying algae, and corals appear to be sensitive. Calcifiers are generally more sensitive at the larval stage than adult stage. Over 70% of the observations in growth and calcification are non-negative, implying the acclimation capacity of many calcifiers to ocean acidification. This capacity can be mediated by phenotypic plasticity (e.g., physiological, mineralogical, structural, and molecular adjustments), transgenerational plasticity, increased food availability, or species interactions. The results suggest that the impacts of ocean acidification on calcifiers are less deleterious than initially thought as their adaptability has been underestimated. Therefore, in the forthcoming era of ocean acidification research, it is advocated that studying how marine organisms persist is as important as studying how they perish, and that future hypotheses and experimental designs are not constrained within the paradigm of negative effects.
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Affiliation(s)
- Jonathan Y S Leung
- Faculty of Materials and Energy, Southwest University, Chongqing, 400715, P. R. China
- Southern Seas Ecology Laboratories, School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Sam Zhang
- Faculty of Materials and Energy, Southwest University, Chongqing, 400715, P. R. China
| | - Sean D Connell
- Southern Seas Ecology Laboratories, School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia
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Boukadida K, Banni M, Romero-Ramirez A, Clerandeau C, Gourves PY, Cachot J. Metal contamination and heat stress impair swimming behavior and acetylcholinesterase activity in embryo-larval stages of the Mediterranean mussel, Mytilus galloprovincialis. MARINE ENVIRONMENTAL RESEARCH 2022; 179:105677. [PMID: 35738152 DOI: 10.1016/j.marenvres.2022.105677] [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: 01/03/2022] [Revised: 04/27/2022] [Accepted: 06/02/2022] [Indexed: 06/15/2023]
Abstract
Behavioral parameters are increasingly considered sensitive and early bioindicators of toxicity in aquatic organisms. A video-tracking tool was specifically developed to monitor the swimming behaviour of D-larvae of the Mediterranean mussel, Mytilus galloprovincialis, in controlled laboratory conditions. Both maximum and average swimming speeds and trajectories were recorded. We then investigated the impact of copper and silver with or without a moderate rise of temperature on swimming behavior and acetylcholinesterase (AChE) activity of mussel D-larvae and the possible mechanistic link between both biological responses. Our results showed that copper and/or silver exposure, as well as temperature increase, disrupts the swimming behavior of mussel larvae which could compromise their dispersal and survival. In addition, the combined effect of temperature and metals significantly (p < 0.05) increased AChE activity in mussel larvae. Pearson's correlation analysis was performed and results showed that the AChE activity is positively correlated with maximum speeds (r = 0.71, p < 0.01). This study demonstrates the value of behavioral analyzes of aquatic invertebrates as a sensitive and integrate marker of the effects of stressors.
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Affiliation(s)
- Khouloud Boukadida
- Laboratory of Oceanic and Continental Environments and Paleoenvironments, University of Bordeaux, EPOC, UMR 5805, F-33600, Pessac, France; Laboratory of Agrobiodiversity and Ecotoxicology, ISA, Chott-Mariem, 4042, Sousse, Tunisia.
| | - Mohamed Banni
- Laboratory of Agrobiodiversity and Ecotoxicology, ISA, Chott-Mariem, 4042, Sousse, Tunisia; Higher Institute of Biotechnology, University of Monastir, Tunisia
| | - Alicia Romero-Ramirez
- Laboratory of Oceanic and Continental Environments and Paleoenvironments, University of Bordeaux, EPOC, UMR 5805, F-33600, Pessac, France
| | - Christelle Clerandeau
- Laboratory of Oceanic and Continental Environments and Paleoenvironments, University of Bordeaux, EPOC, UMR 5805, F-33600, Pessac, France
| | - Pierre-Yves Gourves
- Laboratory of Oceanic and Continental Environments and Paleoenvironments, University of Bordeaux, EPOC, UMR 5805, F-33600, Pessac, France
| | - Jérôme Cachot
- Laboratory of Oceanic and Continental Environments and Paleoenvironments, University of Bordeaux, EPOC, UMR 5805, F-33600, Pessac, France
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Pazoki S, Rahimian H, Struck TH. Genetic diversity and population structure of three Hydroides species (Sedentaria, Serpulidae) in the Persian Gulf and Gulf of Oman, with the possible indication of heteroplasmy. SYST BIODIVERS 2021. [DOI: 10.1080/14772000.2021.1965668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Samaneh Pazoki
- Department of Animal Biology, Faculty of Biology, College of Sciences, University of Tehran, Tehran, Iran
| | - Hassan Rahimian
- Department of Animal Biology, Faculty of Biology, College of Sciences, University of Tehran, Tehran, Iran
| | - Torsten H. Struck
- Natural History Museum, University of Oslo, P.O. Box 1172, Blindern, Oslo, NO-0318, Norway
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Meng Y, Li C, Li H, Shih K, He C, Yao H, Thiyagarajan V. Recoverable impacts of ocean acidification on the tubeworm, Hydroides elegans: implication for biofouling in future coastal oceans. BIOFOULING 2019; 35:945-957. [PMID: 31687858 DOI: 10.1080/08927014.2019.1673376] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 06/10/2023]
Abstract
Ocean uptake of anthropogenic CO2 causes ocean acidification (OA), which not only decreases the calcification rate, but also impairs the formation of calcareous shells or tubes in marine invertebrates such as the dominant biofouling tubeworm species, Hydroides elegans. This study examined the ability of tubeworms to resume normal tube calcification when returned to ambient pH 8.1 from a projected near-future OA level of pH 7.8. Tubeworms produced structurally impaired and mechanically weaker calcareous tubes at pH 7.8 compared to at pH 8.1, but were able to recover when the pH was restored to ambient levels. This suggests that tubeworms can physiologically recover from the impacts of OA on tube calcification, composition, density, hardness and stiffness when returned to optimal conditions. These results help understanding of the progression of biofouling communities dominated by tubeworms in future oceans with low pH induced by OA.
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Affiliation(s)
- Yuan Meng
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Chaoyi Li
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Hangkong Li
- Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Kaimin Shih
- Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Chong He
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - Haimin Yao
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - V Thiyagarajan
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory for Marine Pollution, Hong Kong SAR, China
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Figuerola B, Gore DB, Johnstone G, Stark JS. Spatio-temporal variation of skeletal Mg-calcite in Antarctic marine calcifiers. PLoS One 2019; 14:e0210231. [PMID: 31063495 PMCID: PMC6504097 DOI: 10.1371/journal.pone.0210231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 04/21/2019] [Indexed: 11/29/2022] Open
Abstract
Human driven changes such as increases in oceanic CO2, global warming, petroleum hydrocarbons and heavy metals may negatively affect the ability of marine calcifiers to build their skeletons/shells, especially in polar regions. We examine spatio-temporal variability of skeletal Mg-calcite in shallow water Antarctic marine invertebrates using bryozoan and spirorbids as models in a recruitment experiment of settlement tiles in East Antarctica. Mineralogies were determined for 754 specimens belonging to six bryozoan species (four cheilostome and two cyclostome species) and two spirorbid species from around Casey Station. Intra- and interspecific variability in wt% MgCO3 in calcite among most species was the largest source of variation overall. Therefore, the skeletal Mg-calcite in these taxa seem to be mainly biologically controlled. However, significant spatial variability was also found in wt% MgCO3 in calcite, possibly reflecting local environment variation from sources such as freshwater input and contaminated sediments. Species with high-Mg calcite skeletons (e.g. Beania erecta) could be particularly sensitive to multiple stressors under predictions for near-future global ocean chemistry changes such as increasing temperature, ocean acidification and pollution.
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Affiliation(s)
- Blanca Figuerola
- Smithsonian Tropical Research Institute (STRI), Panama City, Panama.,Biodiversity Research Institute (IrBIO), University of Barcelona, Barcelona, Catalonia, Spain
| | - Damian B Gore
- Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, Australia
| | - Glenn Johnstone
- Antarctic Conservation and Management Program, Australian Antarctic Division, Hobart, Tasmania, Australia
| | - Jonathan S Stark
- Antarctic Conservation and Management Program, Australian Antarctic Division, Hobart, Tasmania, Australia
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Díaz-Castañeda V, Cox TE, Gazeau F, Fitzer S, Delille J, Alliouane S, Gattuso JP. Ocean acidification affects calcareous tube growth in adult stage and reared offspring of serpulid polychaetes. J Exp Biol 2019; 222:jeb.196543. [DOI: 10.1242/jeb.196543] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/15/2019] [Indexed: 01/09/2023]
Abstract
The energetically costly transition from free-swimming larvae to benthic life stage and maintenance of a calcareous structure can make calcifying marine invertebrates vulnerable to ocean acidification. The first goal of this study was to evaluate the impacts of ocean acidification on calcified tube growth for two Serpulidae polychaete worms. Spirorbis sp. and Spirobranchus triqueter were collected at 11 m depth from the Northwest Mediterranean Sea and maintained for 30 and 90 d, at three mean pHT levels (total scale) of 8.1 (ambient), 7.7, and 7.4. Moderately decreased tube elongation rates were observed in both species at a pHT of 7.7 while severe reductions occurred at pHT 7.4. There was visual evidence of dissolution and tubes were more fragile at lower pH but, fragility was not attributed to changes in fracture toughness. Instead, it appeared to be due to the presence of larger alveoli covered in a thinner calcareous layer. The second objective of the study was to test for effects in offspring development of the species S. triqueter. Spawning was induced, and offspring were reared in the same pH conditions the parents experienced. Trochophore size was reduced at the lowest pH level but settlement success was similar across pH conditions. Post-settlement tube growth was most affected. At 38 d post-settlement, juvenile tubes at pHT of 7.7 and 7.4 were half the size of those at pHT 8.1. Results suggest future carbonate chemistry will negatively affect initiation and persistence of both biofouling and epiphytic polychaete tube worms.
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Affiliation(s)
- V. Díaz-Castañeda
- Centro de Investigación Científica y Educación Superior de Ensenada, Departmento de Ecología Marina. Carret. Tij. - Ensenada 3918, C.P. 22860 Ensenada, Baja California, México
| | - T. E. Cox
- University of New Orleans, Department of Biological Sciences 2000 Lakeshore Drive New Orleans, LA, 70148 USA
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230 Villefranche-sur-mer, France
| | - F. Gazeau
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230 Villefranche-sur-mer, France
| | - S. Fitzer
- Institute of Aquaculture, University of Stirling, FK9 4LA, Scotland, UK
| | - J. Delille
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230 Villefranche-sur-mer, France
| | - S. Alliouane
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230 Villefranche-sur-mer, France
| | - J.-P. Gattuso
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230 Villefranche-sur-mer, France
- Institute for Sustainable Development and International Relations, Sciences Po, 27 rue Saint Guillaume, F-75007 Paris, France
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Li C, Meng Y, He C, Chan VBS, Yao H, Thiyagarajan V. Mechanical robustness of the calcareous tubeworm Hydroides elegans: warming mitigates the adverse effects of ocean acidification. BIOFOULING 2016; 32:191-204. [PMID: 26820060 DOI: 10.1080/08927014.2015.1129532] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
Development of antifouling strategies requires knowledge of how fouling organisms would respond to climate change associated environmental stressors. Here, a calcareous tube built by the tubeworm, Hydroides elegans, was used as an example to evaluate the individual and interactive effects of ocean acidification (OA), warming and reduced salinity on the mechanical properties of a tube. Tubeworms produce a mechanically weaker tube with less resistance to simulated predator attack under OA (pH 7.8). Warming (29°C) increased tube volume, tube mineral density and the tube's resistance to a simulated predatory attack. A weakening effect by OA did not make the removal of tubeworms easier except for the earliest stage, in which warming had the least effect. Reduced salinity (27 psu) did not affect tubes. This study showed that both mechanical analysis and computational modeling can be integrated with biofouling research to provide insights into how fouling communities might develop in future ocean conditions.
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Affiliation(s)
- Chaoyi Li
- a The Swire Institute of Marine Sciences and School of Biological Sciences , The University of Hong Kong , Hong Kong SAR , China
| | - Yuan Meng
- a The Swire Institute of Marine Sciences and School of Biological Sciences , The University of Hong Kong , Hong Kong SAR , China
| | - Chong He
- b Department of Mechanical Engineering , The Hong Kong Polytechnic University , Hong Kong SAR , China
| | - Vera B S Chan
- c Department of Biological Sciences , University of Clemson , Clemson , SC , USA
| | - Haimin Yao
- b Department of Mechanical Engineering , The Hong Kong Polytechnic University , Hong Kong SAR , China
| | - V Thiyagarajan
- a The Swire Institute of Marine Sciences and School of Biological Sciences , The University of Hong Kong , Hong Kong SAR , China
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Kroeker KJ, Gaylord B, Hill TM, Hosfelt JD, Miller SH, Sanford E. The role of temperature in determining species' vulnerability to ocean acidification: a case study using Mytilus galloprovincialis. PLoS One 2014; 9:e100353. [PMID: 24984016 PMCID: PMC4077567 DOI: 10.1371/journal.pone.0100353] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 05/27/2014] [Indexed: 11/26/2022] Open
Abstract
Ocean acidification (OA) is occurring across a backdrop of concurrent environmental changes that may in turn influence species' responses to OA. Temperature affects many fundamental biological processes and governs key reactions in the seawater carbonate system. It therefore has the potential to offset or exacerbate the effects of OA. While initial studies have examined the combined impacts of warming and OA for a narrow range of climate change scenarios, our mechanistic understanding of the interactive effects of temperature and OA remains limited. Here, we use the blue mussel, Mytilus galloprovincialis, as a model species to test how OA affects the growth of a calcifying invertebrate across a wide range of temperatures encompassing their thermal optimum. Mussels were exposed in the laboratory to a factorial combination of low and high pCO2 (400 and 1200 µatm CO2) and temperatures (12, 14, 16, 18, 20, and 24°C) for one month. Results indicate that the effects of OA on shell growth are highly dependent on temperature. Although high CO2 significantly reduced mussel growth at 14°C, this effect gradually lessened with successive warming to 20°C, illustrating how moderate warming can mediate the effects of OA through temperature's effects on both physiology and seawater geochemistry. Furthermore, the mussels grew thicker shells in warmer conditions independent of CO2 treatment. Together, these results highlight the importance of considering the physiological and geochemical interactions between temperature and carbonate chemistry when interpreting species' vulnerability to OA.
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Affiliation(s)
- Kristy J. Kroeker
- Bodega Marine Laboratory, University of California Davis, Bodega Bay, California, United States of America
- * E-mail:
| | - Brian Gaylord
- Bodega Marine Laboratory, University of California Davis, Bodega Bay, California, United States of America
- Department of Evolution and Ecology, University of California Davis, Davis, California, United States of America
| | - Tessa M. Hill
- Bodega Marine Laboratory, University of California Davis, Bodega Bay, California, United States of America
- Department of Geology, University of California Davis, Davis, California, United States of America
| | - Jessica D. Hosfelt
- Bodega Marine Laboratory, University of California Davis, Bodega Bay, California, United States of America
| | - Seth H. Miller
- Bodega Marine Laboratory, University of California Davis, Bodega Bay, California, United States of America
| | - Eric Sanford
- Bodega Marine Laboratory, University of California Davis, Bodega Bay, California, United States of America
- Department of Evolution and Ecology, University of California Davis, Davis, California, United States of America
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Zhang H, Cheung SG, Shin PKS. The larvae of congeneric gastropods showed differential responses to the combined effects of ocean acidification, temperature and salinity. MARINE POLLUTION BULLETIN 2014; 79:39-46. [PMID: 24456853 DOI: 10.1016/j.marpolbul.2014.01.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 12/18/2013] [Accepted: 01/03/2014] [Indexed: 06/03/2023]
Abstract
The tolerance and physiological responses of the larvae of two congeneric gastropods, the intertidal Nassarius festivus and subtidal Nassarius conoidalis, to the combined effects of ocean acidification (pCO2 at 380, 950, 1250 ppm), temperature (15, 30°C) and salinity (10, 30 psu) were compared. Results of three-way ANOVA on cumulative mortality after 72-h exposure showed significant interactive effects in which mortality increased with pCO2 and temperature, but reduced at higher salinity for both species, with higher mortality being obtained for N. conoidalis. Similarly, respiration rate of the larvae increased with temperature and pCO2 level for both species, with a larger percentage increase for N. conoidalis. Larval swimming speed increased with temperature and salinity for both species whereas higher pCO2 reduced swimming speed in N. conoidalis but not N. festivus. The present findings indicated that subtidal congeneric species are more sensitive than their intertidal counterparts to the combined effects of these stressors.
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Affiliation(s)
- Haoyu Zhang
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - Paul K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong, China.
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