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Liu HM, Grist EPM, Xu XY, Lo HS, Wong ACY, Cheung SG. Microplastics pollution in the rivers of a metropolitan city and its estimated dependency on surrounding developed land. Sci Total Environ 2023; 880:163268. [PMID: 37031935 DOI: 10.1016/j.scitotenv.2023.163268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/29/2023] [Accepted: 03/31/2023] [Indexed: 04/14/2023]
Abstract
The spatial distribution and abundance of suspected microplastics (SMPs) in the surface water of a metropolitan city, as represented by four Hong Kong rivers, was studied during the dry season. Shing Mun River (SM), Lam Tsuen River (LT), and Tuen Mun River (TM) are located in urbanized areas, and SM and TM are tidal rivers. The fourth river, Silver River (SR) is situated in a rural area. TM had a significantly higher SMP abundance (53.80 ± 20.67 n/L) than the other rivers. The SMP abundance increased from upstream to downstream in non-tidal rivers (LT and SR), but not in tidal rivers (TM and SM), probably due to the tidal influence and a more homogeneous urban development along the tidal rivers. Inter-site differences in the SMP abundance were strongly correlated with the built area ratio (defined as the percentage of surrounding developed land area), human activities, and the nature of the river. About half (48.72 %) of the SMPs were <250 μm. Fibers and fragments were most abundant (>98 %), with most of them being transparent (58.54 %), black (14.68 %), or blue (12.12 %). Polyethylene terephthalate (26.96 %) and polyethylene (20.70 %) were the most common polymers. However, the MP abundance could be overestimated due to the presence of natural fibers. By contrast, an underestimation of the MP abundance could result from a smaller volume of water samples collected, due to a low filtration efficiency caused by high organic content and particle concentrations in the water. A more effective solid waste management strategy and upgrading of the sewage treatment facilities for removing microplastics are recommended to ameliorate the microplastic pollution in local rivers.
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Affiliation(s)
- H M Liu
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Eric P M Grist
- College of Engineering, Mathematics & Physical Sciences, University of Exeter, Exeter, United Kingdom
| | - X Y Xu
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - H S Lo
- Department of Environmental Science, Stockholm University, SE-106 91 Stockholm, Sweden
| | - A C Y Wong
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - S G Cheung
- Department of Chemistry, City University of Hong Kong, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
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2
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Zhang K, Xu S, Zhang Y, Lo Y, Liu M, Ma Y, Chau HS, Cao Y, Xu X, Wu R, Lin H, Lao J, Tao D, Lau FTK, Chiu SC, Wong GTN, Lee K, Ng DCM, Cheung SG, Leung KMY, Lam PKS. A systematic study of microplastic occurrence in urban water networks of a metropolis. Water Res 2022; 223:118992. [PMID: 36007402 DOI: 10.1016/j.watres.2022.118992] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 07/22/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
The release of microplastics from sewage treatment works (STWs) into the oceans around coastal cities is well documented. However, there are fewer studies on the microplastic abundance in stormwater drains and their emissions into the coastal marine environment via sewage and stormwater drainage networks. Here, we comprehensively investigated microplastic abundance in 66 sewage and 18 sludge samples collected from different process stages at three typical STWs and 36 water samples taken from six major stormwater drains during the dry and wet seasons in Hong Kong, which is a metropolitan city in south China. The results showed that microplastics were detected in all the sewage and stormwater samples, with the abundance ranging from 0.07 to 91.9 and from 0.4 to 36.48 particles/L, respectively, and in all the sludge samples with the abundance ranging from 167 to 936 particles/g (d. w.). There were no significant seasonal variations in the microplastic abundance across all samples of sewage, sludge, and stormwater. For both waterborne sample types, a smaller size (0.02-0.3 mm) and fiber shape were the dominant characteristics of the microplastics. Polyethylene terephthalate (PET) and polypropylene (PP) were the most abundant polymer types in the sewage samples, while polyethylene (PE), PET, PP, and PE-PP copolymer were the most abundant polymer types in the stormwater samples. The estimated range of total daily microplastic loads in the effluent from STWs in Hong Kong is estimated to be 4.48 × 109 - 2.68 × 1010 particles/day, demonstrating that STWs are major pathways of microplastics in coastal environments despite the high removal percentage of microplastics in sewage treatment processes examined. This is the first comprehensive study on microplastics in the urban waters of a coastal metropolis. However, further studies on other coastal cities will enable an accurate estimation of the microplastic contribution of stormwater drains to the world's oceans.
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Affiliation(s)
- Kai Zhang
- National Observation and Research Station of Coastal Ecological Environments in Macao, Macao Environmental Research Institute, Macau University of Science and Technology, Macao SAR, China; State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Center for Ocean Research in Hong Kong and Macau (CORE), The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Shaopeng Xu
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | | | - Yuki Lo
- AECOM Asia Company Limited, Hong Kong SAR, China
| | - Mengyang Liu
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Yue Ma
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Hoi Shan Chau
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Yaru Cao
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Xiaoyu Xu
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Rongben Wu
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Huiju Lin
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Jiayong Lao
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Danyang Tao
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Frankie T K Lau
- Drainage Services Department, Government of the Hong Kong SAR, Hong Kong SAR, China
| | - Sze-Ching Chiu
- Drainage Services Department, Government of the Hong Kong SAR, Hong Kong SAR, China
| | - Gina T N Wong
- Drainage Services Department, Government of the Hong Kong SAR, Hong Kong SAR, China
| | - Katie Lee
- Drainage Services Department, Government of the Hong Kong SAR, Hong Kong SAR, China
| | | | - Siu-Gin Cheung
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China
| | - Kenneth M Y Leung
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China.
| | - Paul K S Lam
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China; Center for Ocean Research in Hong Kong and Macau (CORE), The Hong Kong University of Science and Technology, Hong Kong SAR, China; Department of Science, School of Science and Technology, Hong Kong Metropolitan University, Hong Kong SAR, China.
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3
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Xu X, Fang JKH, Wong CY, Cheung SG. The significance of trophic transfer in the uptake of microplastics by carnivorous gastropod Reishia clavigera. Environ Pollut 2022; 298:118862. [PMID: 35063545 DOI: 10.1016/j.envpol.2022.118862] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/12/2022] [Accepted: 01/15/2022] [Indexed: 06/14/2023]
Abstract
The present study compared the relative significance of prey consumption and respiration as routes of microplastic (MP) intake in a carnivorous muricid gastropod, Reishia clavigera. The time-dependent accumulation of MPs within 14-day exposure and their removal through depuration were also investigated for two forms of MPs (fibre, fragment) at an environmentally relevant concentration (10 items L-1) and two higher concentrations (100 and 1000 items L-1). At 1000 items L-1, the number of MPs in R. clavigera on Day 14 was 1.8 ± 0.2 fibres individual-1 or 0.8 ± 0.3 fragments individual-1, equivalent to 64.6% of the fibres or 9.4% of the fragments retained by the variable mussel Brachidontes variabilis, a prey of R. clavigera. Consumption of B. variabilis was the most important route of MP intake in R. clavigera, although a small number of MPs were adhered to the gills during ventilation. Depuration in clean seawater without MPs was very effective in eliminating MPs in the body of R. clavigera but the possibility of long-term bioaccumulation of MPs could not be ruled out. The high percentage of MPs transferred from the prey to predator indicates the potential of trophic transfer as a significant route of uptake for MPs in higher predators.
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Affiliation(s)
- Xiaoyu Xu
- Department of Chemistry, City University of Hong Kong, Kowloon Tong, Hong Kong, China
| | - James Kar-Hei Fang
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China; Research Institute for Future Food, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon Tong, Hong Kong, China
| | - Chun-Yuen Wong
- Department of Chemistry, City University of Hong Kong, Kowloon Tong, Hong Kong, China
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Kowloon Tong, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon Tong, Hong Kong, China.
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Ouyang X, Duarte CM, Cheung SG, Tam NFY, Cannicci S, Martin C, Lo HS, Lee SY. Fate and Effects of Macro- and Microplastics in Coastal Wetlands. Environ Sci Technol 2022; 56:2386-2397. [PMID: 35089026 DOI: 10.1021/acs.est.1c06732] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Coastal wetlands trap plastics from terrestrial and marine sources, but the stocks of plastics and their impacts on coastal wetlands are poorly known. We evaluated the stocks, fate, and biological and biogeochemical effects of plastics in coastal wetlands with plastic abundance data from 112 studies. The representative abundance of plastics that occurs in coastal wetland sediments and is ingested by marine animals reaches 156.7 and 98.3 items kg-1, respectively, 200 times higher than that (0.43 items kg-1) in the water column. Plastics are more abundant in mangrove forests and tidal marshes than in tidal flats and seagrass meadows. The variation in plastic abundance is related to climatic and geographic zones, seasons, and population density or plastic waste management. The abundance of plastics ingested by pelagic and demersal fish increases with fish length and dry weight. The dominant characteristics of plastics ingested by marine animals are correlated with those found in coastal wetland sediments. Microplastics exert negative effects on biota abundance and mangrove survival but positive effects on sediment nutrients, leaf drop, and carbon emission. We highlight that plastic pollution is widespread in coastal wetlands and actions are urged to include microplastics in ecosystem health and degradation assessment.
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Affiliation(s)
- Xiaoguang Ouyang
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong, Shatin 999077, Hong Kong Special Administrative Region, China
| | - Carlos M Duarte
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology, Thuwal 23955, Kingdom of Saudi Arabia
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong Special Administrative Region, China
| | - Nora Fung-Yee Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong Special Administrative Region, China
- Department of Science, School of Science and Technology, Hong Kong Metropolitan University, Ho Man Tin 999077, Hong Kong Special Administrative Region, China
| | - Stefano Cannicci
- The Swire Institute of Marine Sciences and the Area of Ecology and Biodiversity, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Pokfulam 999077, Hong Kong Special Administrative Region, China
- Department of Biology, University of Florence, Via Madonna Del Piano 6, 50019 Sesto Fiorentino, Italy
| | - Cecilia Martin
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology, Thuwal 23955, Kingdom of Saudi Arabia
| | - Hoi Shing Lo
- Department of Science, School of Science and Technology, Hong Kong Metropolitan University, Ho Man Tin 999077, Hong Kong Special Administrative Region, China
- Department of Environmental Science, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Shing Yip Lee
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong, Shatin 999077, Hong Kong Special Administrative Region, China
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Leung MML, Ho YW, Maboloc EA, Lee CH, Wang Y, Hu M, Cheung SG, Fang JKH. Determination of microplastics in the edible green-lipped mussel Perna viridis using an automated mapping technique of Raman microspectroscopy. J Hazard Mater 2021; 420:126541. [PMID: 34587714 DOI: 10.1016/j.jhazmat.2021.126541] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 06/11/2021] [Accepted: 06/28/2021] [Indexed: 06/13/2023]
Abstract
Microplastics are prevalent in marine environments and seafood and thus can easily end up in human diets. This has raised serious concerns worldwide, particularly in Hong Kong where the seafood consumption per capita can be three times higher than the global average. This study focused on the green-lipped mussel Perna viridis, a popular seafood species which is subject to a high risk of contamination by microplastics due to its filter-feeding nature. P. viridis was collected from five mariculture sites in Hong Kong and assessed for its body load of microplastics using an automated Raman mapping approach. Microplastics were found in all sites, with an average of 1.60-14.7 particles per mussel per site, or 0.21-1.83 particles per g wet weight. Polypropylene, polyethylene, polystyrene and polyethylene terephthalate were detected among the microplastics, mainly as fragments or fibres in the size range of 40-1000 µm. It was estimated that through consumption of P. viridis, the population in Hong Kong could ingest up to 10,380 pieces of microplastics per person per year. These estimated rates were high compared to the values reported worldwide, suggesting the potential human health risk of microplastics in Hong Kong and adjacent areas.
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Affiliation(s)
- Matthew Ming-Lok Leung
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Yuen-Wa Ho
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Elizaldy Acebu Maboloc
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Cheng-Hao Lee
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China; Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China
| | - Youji Wang
- International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
| | - Menghong Hu
- International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China
| | - Siu-Gin Cheung
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong SAR, China; Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - James Kar-Hei Fang
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong SAR, China; Research Institute for Future Food, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China.
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Li FL, Zhong L, Wen W, Tian TT, Li HC, Cheung SG, Wong YS, Shin PKS, Zhou HC, Tam NFY, Song X. Do distribution and expansion of exotic invasive Asteraceae plants relate to leaf construction cost in a man-made wetland? Mar Pollut Bull 2021; 163:111958. [PMID: 33444997 DOI: 10.1016/j.marpolbul.2020.111958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 12/13/2020] [Accepted: 12/17/2020] [Indexed: 06/12/2023]
Abstract
Exotic species especially Asteraceae plants severely invade wetlands in Shenzhen Bay, an important part of the coast wetland in Guangdong-Hong Kong-Macau Bay Area, China. However, the reasons causing their expansion are unclear. The leaf traits and expansion indices of six invasive Asteraceae plants from the Overseas Chinese Town (OCT) wetland were studied and the results showed that nearly 45% of the total plant species (31 out of 69 species) in the OCT wetland, belonging to 15 families and 27 genera, were exotic invasive species. The expansion indices of six Asteraceae species negatively correlated with their leaf construction cost based on mass (CCM), caloric values and carbon concentration, but their relations with ash content were positive. Multiple linear regression analysis revealed that CCM was the most important factor affecting the expansion of an exotic species, indicating CCM may be an important reason causing the expansion of exotic species in coastal wetlands.
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Affiliation(s)
- F L Li
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China
| | - L Zhong
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China
| | - W Wen
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China
| | - T T Tian
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangdong Academy of Sciences, Guangzhou, China
| | - H C Li
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China
| | - S G Cheung
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - Y S Wong
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; School of Science and Technology, Open University of Hong Kong, Hong Kong, China
| | - P K S Shin
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - H C Zhou
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China
| | - N F Y Tam
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
| | - X Song
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China.
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Po BHK, Lo HS, Cheung SG, Lai KP. Characterisation of an unexplored group of microplastics from the South China Sea: Can they be caused by macrofaunal fragmentation? Mar Pollut Bull 2020; 155:111151. [PMID: 32469771 DOI: 10.1016/j.marpolbul.2020.111151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 03/29/2020] [Accepted: 04/02/2020] [Indexed: 06/11/2023]
Abstract
Research on plastics fragmentation is important for the estimation of amount of microplastics but the biological causes for fragmentation have not been acknowledged. From microplastics collected in the beaches of Hong Kong, we revealed an abnormal type of fragment which has not been reported before. These fragments, composing about 6% of the microplastics (pellet, foam, bead, fragment) collected, were interestingly triangular in shape with at least two of the three sides being characteristically straight and resembling a cut made by compression. Objective observations have distinguished these "trimmed triangular fragments" to those triangular fragments that were fractured randomly. By comparing with additional evidence, we proposed that these trimmed fragments were the daughter pieces of macrofaunal biting. If this was so, there would be wide implications on fragmentation modeling studies for microplastics since active biting of large plastic debris has generally not been considered as a factor of plastics fragmentation.
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Affiliation(s)
- Beverly Hoi-Ki Po
- Department of Chemistry, City University of Hong Kong, Hong Kong, China; Department of Zoology, University of British Columbia, Vancouver, Canada
| | - Hoi-Shing Lo
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - Keng-Po Lai
- Guangxi Key Laboratory of Tumor Immunology and Microenvironmental Regulation, Guilin Medical University, Guilin, PR China; Department of Chemistry, City University of Hong Kong, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
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Lo HS, Lee YK, Po BHK, Wong LC, Xu X, Wong CF, Wong CY, Tam NFY, Cheung SG. Impacts of Typhoon Mangkhut in 2018 on the deposition of marine debris and microplastics on beaches in Hong Kong. Sci Total Environ 2020; 716:137172. [PMID: 32059298 DOI: 10.1016/j.scitotenv.2020.137172] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/03/2020] [Accepted: 02/06/2020] [Indexed: 06/10/2023]
Abstract
Storm surge and waves associated with tropical cyclones carry significant amounts of pollutants into the marine environment. This study evaluated the effects of Typhoon Mangkhut (7-18 September 2018) on marine debris pollution including macro-debris (>2.5 cm) and microplastics (5 μm-5 mm) in Hong Kong. Sampling was repeated on four beaches, two each from protected and exposed coastal areas, spanning from the eastern to western waters before and after the cyclone. For macro-debris, an average density of 0.047 items m-2 and 0.54 items m-2 was obtained before and after the cyclone, respectively or an 11.4-fold increase, with plastic being the most dominant type (61.9-93.3% and 80.7-92.4% before and after the cyclone, respectively) among total beached debris in all four beaches. Likewise, higher mean microplastic abundances were found in the post-cyclone period (335 items kg-1 sediment) when compared with the pre-cyclone period (188 items kg-1 sediment). The depositional dynamics for both macro-debris and microplastic were site-specific due to factors such as wind direction and the associated storm surge, topography and orientation of the site, and proximity to urban areas. This study has demonstrated the role cyclone induced overwash plays on introducing plastic pollution to beach environments. Considering an increase in both the intensity and frequency of cyclone in the future due to global warming, and a tremendous increase in marine plastic debris, more research effort should be spent on this understudied problem.
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Affiliation(s)
- Hoi-Shing Lo
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Yan-Kin Lee
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Beverly Hoi-Ki Po
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Leung-Chun Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Xiaoyu Xu
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Cheuk-Fung Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Chun-Yuen Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Nora Fung-Yee Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region; State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region.
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9
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Xu XY, Wong CY, Tam NFY, Liu HM, Cheung SG. Barnacles as potential bioindicator of microplastic pollution in Hong Kong. Mar Pollut Bull 2020; 154:111081. [PMID: 32319909 DOI: 10.1016/j.marpolbul.2020.111081] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 03/15/2020] [Accepted: 03/16/2020] [Indexed: 06/11/2023]
Abstract
Microplastic (MP) pollution is an emerging problem in the marine environment and the assessment of the presence and abundance of microplastics in wild organisms is essential for risk assessment. The occurrence of microplastics in four species of barnacles at 30 sites in Hong Kong waters was investigated. The median number of microplastics ranged between 0 and 8.63 particles g-1 wet weight, or 0 and 1.9 particles individual-1, with fibers being the most abundant type of microplastics. The chemical composition of 152 pieces out of 606 potential microplastics was analyzed using micro-Fourier Transform Infrared Spectroscopy (μ-FTIR). Fifty-two of them were synthetic polymers, 95 natural cotton fibers and five unknowns. Eight types of polymer were identified with cellophane being the most abundant (58%). Correlation analysis was conducted between the abundance of MPs in sediments obtained in our previous study and that in individual barnacle species in this study, and a positive correlation was established for the barnacle Amphibalanus amphitrite, highlighting the potential of using this species as a bioindicator of microplastics.
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Affiliation(s)
- X-Y Xu
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - C Y Wong
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - N F Y Tam
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - H M Liu
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - S G Cheung
- Department of Chemistry, City University of Hong Kong, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China.
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Xu X, Wong CY, Tam NFY, Lo HS, Cheung SG. Microplastics in invertebrates on soft shores in Hong Kong: Influence of habitat, taxa and feeding mode. Sci Total Environ 2020; 715:136999. [PMID: 32023520 DOI: 10.1016/j.scitotenv.2020.136999] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/09/2020] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
Microplastic (MP) pollution in the marine environment has gained much concern in recent years. This study investigated the occurrence of MPs in invertebrates collected on 18 mudflats and sandy beaches in Hong Kong and its relationships to biological taxon, feeding mode and habitat. In total 38 species of gastropods, bivalves and crabs were collected and the mean number of suspected microplastics ranged from 0 to 9.68 particles g-1 wet weight or 0 to 18.4 particles individual-1. Around 26% of the suspected microplastics were confirmed to be synthetic polymers, including CP (cellophane), PET (polyethylene terephthalate), and PA (polyamide). Microplastic fibres were the most abundant type of MPs, followed by pellets. Significantly higher abundance of suspected microplastics was found in gastropods. Since MP abundance might vary with taxon, it is recommended to include different taxonomic groups in any ecological assessment of the impact of MPs.
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Affiliation(s)
- Xiaoyu Xu
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, China
| | - C Y Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, China
| | - Nora F Y Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, China
| | - Hoi-Shing Lo
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, China
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong, China.
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11
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Li W, Lo HS, Wong HM, Zhou M, Wong CY, Tam NFY, Cheung SG. Heavy metals contamination of sedimentary microplastics in Hong Kong. Mar Pollut Bull 2020; 153:110977. [PMID: 32275534 DOI: 10.1016/j.marpolbul.2020.110977] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 02/10/2020] [Accepted: 02/10/2020] [Indexed: 06/11/2023]
Abstract
This is the first study of heavy metals (As, Zn, Cd, Ni, Fe, Mn, Cu) contamination of microplastics on sandy beaches in Hong Kong. Three study sites are located in the eastern waters (Pak Lap Wan, Stanley Bay, Tung Lung Chau) and the other three in the western waters (Tai Pai Tsui, Ha Pak Nai, Shui Hau Wan). The three most abundant types of microplastics were polyethylene (42.2%), polypropylene (23.3%) and polystyrene (19.5%). The median concentration of Fe (302 mg kg-1) was the highest and followed by Zn (19.6 mg kg-1) and Mn (18.6 mg kg-1). Very low concentrations of Cu (0.89 mg kg-1), Ni (0.15 mg kg-1), As (<LOD) and Cd (<LOD) were measured. The western sites have significantly higher concentrations of Ni, Fe, Mn and Cu than the eastern sites, indicating that Pearl River was likely to be a major source of heavy metals on microplastics. In view of a continual increase in the abundance of microplastics in the marine environment and its potential impacts on marine organisms, immediate actions should be taken in establishing long term monitoring programs for heavy metals associated with microplastics. In-depth research on the mechanisms of adsorption and desorption processes between metals and microplastics will help assess the associated risks to both human health and the environment.
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Affiliation(s)
- Wenjie Li
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Hoi-Shing Lo
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Ho-Man Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Man Zhou
- Research Institute for Environmental Innovation (Suzhou), Tsinghua, RIET, Jinfeng Road, Suzhou, China
| | - Chun-Yuen Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Nora Fung-Yee Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region; State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region.
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12
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Pan Y, Chen J, Zhou H, Cheung SG, Tam NFY. Degradation of BDE-47 in mangrove sediments with amendment of extra carbon sources. Mar Pollut Bull 2020; 153:110972. [PMID: 32056850 DOI: 10.1016/j.marpolbul.2020.110972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/09/2020] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are widely detected in coastal wetlands but their remediation is still difficult. In this study, different carbon sources, namely formate, acetate, pyruvate, lactate, succinate, methanol and ethanol, were added to mangrove sediments contaminated with BDE-47, a common PBDE congener, to enhance its degradation. After 2-month incubation, all carbon addition significantly enhanced degradation percentages. The residual BDE-47 percentage significantly correlated with the abundance of total bacteria and Dehalococcoides spp. The addition of methanol, acetate and succinate also achieved significantly higher degradation rates and shorter half-lives than sediments without carbon amendment at the end of 5-month incubation, although degradation percentages were comparable between sediments with and without extra carbon. The degradation pathway based on the profiles of degradation products was also similar among treatments. The results indicated the stimulatory effect of extra carbon sources on BDE-47 degradation in contaminated sediments was carbon- and time-specific.
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Affiliation(s)
- Ying Pan
- College of Oceanography, Hohai University, Xikang Road, Nanjing 210098, PR China; Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Juan Chen
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Xikang Road, Nanjing 210098, PR China
| | - Haichao Zhou
- College of Life Sciences and Oceanography, Shenzhen University, Nanhai Avenue, 518060, PR China
| | - S G Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Nora F Y Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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13
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Li FL, Zhong L, Cheung SG, Wong YS, Shin PKS, Lei AP, Zhou HC, Song X, Tam NFY. Is Laguncularia racemosa more invasive than Sonneratia apetala in northern Fujian, China in terms of leaf energetic cost? Mar Pollut Bull 2020; 152:110897. [PMID: 31957670 DOI: 10.1016/j.marpolbul.2020.110897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 06/10/2023]
Abstract
Laguncularia racemosa and Sonneratia apetala are fast-growing exotic mangrove species in Southern China and widely used for afforestation. However, the invasiveness of the two exotic species is still unclear. We compared structural and physiological traits and energy-use related traits between L. racemosa and S. apetala, and with two natives (Kandelia obovata and Aegiceras corniculatum) in northern Fujian. Results showed that leaf construction cost based on mass (CCM) and caloric values of L. racemosa were significantly lower than S. apetala, and the two natives had highest CCM. Because lower CCM, L. racemosa grew faster with a taller height (4.83 m) and wider ground diameter circumference (40.03 cm) than S. apetala (4.43 m tall and 35.63 cm wide) and the two natives (2.42 m tall and 26.78 cm wide). These findings indicated that L. racemosa could be more invasive than S. apetala in mangrove forests in northern Fujian, China where it still grew well, which deserves more attention.
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Affiliation(s)
- F L Li
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China
| | - L Zhong
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China
| | - S G Cheung
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Y S Wong
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; School of Science and Technology, Open University of Hong Kong, Hong Kong, China
| | - P K S Shin
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - A P Lei
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China
| | - H C Zhou
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China
| | - X Song
- College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bio-resource and Eco-environmental Science, Shenzhen University, Shenzhen, China.
| | - N F Y Tam
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, China; Department of Chemistry, City University of Hong Kong, Hong Kong, China.
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14
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Li F, Mu FH, Liu XS, Xu XY, Cheung SG. Predator prey interactions between predatory gastropod Reishia clavigera, barnacle Amphibalanusamphitriteamphitrite and mussel Brachidontesvariabilis under ocean acidification. Mar Pollut Bull 2020; 152:110895. [PMID: 31957674 DOI: 10.1016/j.marpolbul.2020.110895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 01/05/2020] [Accepted: 01/08/2020] [Indexed: 06/10/2023]
Abstract
Since the response to ocean acidification is species specific, differences in responses between predator and prey will alter their interactions, hence affect the population dynamics of both species. Changes in predator prey interactions between a predatory muricid gastropod Reishia clavigera and its prey, the barnacle Amphibalanus amphitrite amphitrite and mussel Brachidontes variabilis under three pCO2 levels (380, 950, and 1250 μatm) were investigated. The searching time for barnacles increased and the ability to locate them decreased at higher pCO2 levels. The movement speed and the prey consumption rate, however, were independent of pCO2. There was no preference towards either B. variabilis or A. amphitrite amphitrite regardless of pCO2. Exposure experiments involving multiple generations are suggested to assess transgenerational effects of ocean acidification and the potential compensation responses before any realistic predictions on the long term changes of population dynamics of the interacting species can be made.
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Affiliation(s)
- F Li
- College of Marine Life, Ocean University of China, Qingdao, China
| | - F-H Mu
- College of Marine Life, Ocean University of China, Qingdao, China
| | - X-S Liu
- College of Marine Life, Ocean University of China, Qingdao, China
| | - X-Y Xu
- Department of Chemistry, City University of Hong Kong, Hong Kong
| | - S G Cheung
- Department of Chemistry, City University of Hong Kong, Hong Kong; State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong.
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15
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Lo HS, Wong LC, Kwok SH, Lee YK, Po BHK, Wong CY, Tam NFY, Cheung SG. Field test of beach litter assessment by commercial aerial drone. Mar Pollut Bull 2020; 151:110823. [PMID: 32056615 DOI: 10.1016/j.marpolbul.2019.110823] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 11/25/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
The visual survey is the most common method to quantify and characterize beach litter. However, it is very labor intensive and difficult to carry out on beaches which are remote or difficult to access. We suggest an alternative approach for assessing beach litter using an unmanned aerial vehicle (UAV), or aerial drone, with automated image requisition and processing. Litter of different sizes, colours, and materials were placed randomly on two beaches. Images of beaches with different substrates were obtained by the drone at different operating heights and light conditions and litter on the beaches was identified from the photos by untrained personnel. The quantification of beach litter using the drone was three times faster than that by visual census. This study has demonstrated the potential of using the drone as a cost-effective and an efficient sampling method in routine beach litter monitoring programs.
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Affiliation(s)
- Hoi-Shing Lo
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Leung-Chun Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Shu-Hin Kwok
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Yan-Kin Lee
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Beverly Hoi-Ki Po
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Chun-Yuen Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Nora Fung-Yee Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region; State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region.
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16
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Zhou H, Tam NFY, Cheung SG, Wei P, Li S, Wu Q. Contamination of polybrominated diphenyl ethers (PBDEs) in watershed sediments and plants adjacent to e-waste sites. J Hazard Mater 2019; 379:120788. [PMID: 31254788 DOI: 10.1016/j.jhazmat.2019.120788] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 06/10/2019] [Accepted: 06/15/2019] [Indexed: 06/09/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are one of the persistent toxic organic pollutants in watersheds near electrical and electronic waste (e-waste) sites (EWS). Spatial redistribution, translocation and bioaccumulation of PBDEs in natural sediment-plant ecosystems, however, are still unclear. The contamination and distribution of PBDEs in core sediments and wetland plants from two EWS and two mangrove forest sites (MFS) were investigated. The eight PBDE congeners were all detected in plant tissue and sediment samples, indicating PBDE contamination was common and severe, and their spatial variations were significant. Although sediments from EWS had higher PBDE concentrations than those in MFS, with an extremely high value of 36392 ± 5992 ng g-1 dw, mangroves could be the sink of PBDEs, as high concentrations (327 ± 48 ng g-1 dw) were also detected in mangrove sediments. The historical usage of PBDEs was reflected by their distribution in mangrove sediment core but not so in e-waste sediment core. PBDEs were taken up and accumulated in six wetland plants, with more accumulation in mangrove plants. These results demonstrated that PBDEs were not only contaminated in sediments adjacent to e-waste sites but also plant tissues. PBDEs could enter other environments via plant littering and/or herbivorous processes that must not be neglected.
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Affiliation(s)
- Haichao Zhou
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China; Futian-CityU Mangrove Research & Development Centre, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Nora F Y Tam
- Futian-CityU Mangrove Research & Development Centre, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China; Department of Chemistry, City University of Hong Kong, Hong Kong, China.
| | - S G Cheung
- Futian-CityU Mangrove Research & Development Centre, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China; Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Pingping Wei
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China; Futian-CityU Mangrove Research & Development Centre, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Shuangfei Li
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Qihang Wu
- Collaborative Innovation Center of Water Quality Safety and Protection in Pearl River Delta, Guangzhou University, Guangzhou, China
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17
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Pan Y, Chen J, Zhou H, Cheung SG, Tam NFY. Degradation of BDE-47 in mangrove sediments under alternating anaerobic-aerobic conditions. J Hazard Mater 2019; 378:120709. [PMID: 31203118 DOI: 10.1016/j.jhazmat.2019.05.102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 06/09/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) resistant to degradation have significant environmental impacts. Anaerobic reductive debromination and aerobic oxidation of PBDEs by microorganisms are main removal mechanisms during natural attenuation, but previous studies often focused on the process under either aerobic or anaerobic condition leading to unsatisfactory removal. The present study aims to remove PBDEs by employing alternating anaerobic-aerobic condition, which is common in inter-tidal mangrove sediments, and elucidate the degradation pathways. During 40-week experiment, BDE-47 reduced with an accumulation of tri-BDEs and di-BDEs as debromination products in all sediments. However, the removal percentages of BDE-47 and the concentrations of debromination congeners varied among flushing regimes. Sediments under less frequent flushing regime (longer duration of aerobic period) had significantly lower concentration and proportion of debromination products, especially BDE-17, than that under more frequent regime (longer anaerobic period). BDE-17 then went through aerobic degradation pathway, as evidenced by the accumulation of its hydroxylation form. Microbial analyses further revealed that less frequent regime favored accumulation of biphenyl dioxygenase gene for aerobic degradation, while more frequent tidal regime promoted growth of dehalogenating bacteria for reductive debromination. This study first time demonstrated that PBDEs in contaminated sediments could be removed under alternating anaerobic-aerobic conditions.
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Affiliation(s)
- Ying Pan
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, PR China; College of Oceanography, Hohai University, Xikang Road, Nanjing 210098, PR China
| | - Juan Chen
- Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Xikang Road, Nanjing 210098, PR China
| | - Haichao Zhou
- College of Life Sciences and Oceanography, Shenzhen University, Nanhai Avenue, Shenzhen 518060, PR China
| | - S G Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, PR China
| | - Nora F Y Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, PR China.
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18
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Lo HS, Wong CY, Tam NFY, Cheung SG. Spatial distribution and source identification of hydrophobic organic compounds (HOCs) on sedimentary microplastic in Hong Kong. Chemosphere 2019; 219:418-426. [PMID: 30551108 DOI: 10.1016/j.chemosphere.2018.12.032] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 11/27/2018] [Accepted: 12/05/2018] [Indexed: 06/09/2023]
Abstract
The spatial distribution, composition and source of hydrophobic organic compounds (HOCs) including polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorinated pesticides (OCPs) of the sedimentary microplastics (0.25-5 mm) in Hong Kong were investigated. The concentration of ΣPAHs ranged between 70.8 and 1509 ng g-1 with inter-site differences although the regional difference was insignificant, indicating localised pyrolytic and petrogenic input of PAHs. The concentration of ΣPCBs (13-1083 ng g-1) varied with both study sites and regions with higher concentrations obtained in the western waters, possibly due to the input from Pearl River. Significantly higher concentrations of OCPs on eastern shores highlighted fishing and aquaculture activities in South China Sea a potential major source of OCPs. DDT and its metabolites (DDX, ranged from 1.96 to 626 ng g-1) were the dominant forms of OCPs (45%-80%). Since most of the DDX existed as DDT, this suggested that there was a fresh input of DDT into the microplastics. As microplastics and HOCs cannot be removed effectively from the environment, reduction of potential ecotoxicological risks should rely on minimizing the use of plastics and HOCs.
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Affiliation(s)
- Hoi-Shing Lo
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Chun-Yuen Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Nora Fung-Yee Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region; State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region.
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19
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Lo HS, Xu X, Wong CY, Cheung SG. Comparisons of microplastic pollution between mudflats and sandy beaches in Hong Kong. Environ Pollut 2018; 236:208-217. [PMID: 29414341 DOI: 10.1016/j.envpol.2018.01.031] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 01/12/2018] [Accepted: 01/12/2018] [Indexed: 06/08/2023]
Abstract
Most of the previous studies of microplastic pollution on coastal habitats focused on high energy beaches although low energy areas such as mudflats are supposed to retain more microplastics, not to mention that mudflats are biologically more diverse. We quantified and characterized microplastics from 10 mudflats and 10 sandy beaches in Hong Kong spanning from the eastern to western waters. Sediment samples were collected at 1.0 m and 1.5 m above chart datum (CD) and at the strandline. Abundance of microplastics ranged between 0.58 and 2116 items kg-1 sediment with that on mudflats being ten times more than on beaches. Polyethylene (46.9%) was the most abundant and followed by polypropylene (13.8%) and polyethylene terephthalate (13.5%). Expanded polystyrene was the most abundant in the strandline samples but not at 1.0 m and 1.5 m above CD. Although previous studies have concluded that the input from Pearl River is a major source of microplastics on Hong Kong shores, this study has demonstrated that the contribution of local pollution sources such as discharge from sewage treatment plants to microplastic pollution should not be neglected.
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Affiliation(s)
- Hoi-Shing Lo
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region; Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, PR China
| | - Xiaoyu Xu
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region
| | - Chun-Yuen Wong
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region; Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518057, PR China
| | - Siu-Gin Cheung
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region; State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong Special Administrative Region.
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20
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Kwan BKY, Cheung SG, Chan AKY, Shin PKS. Trophic and growth baseline of dominant subtidal gastropods in contrasting subtropical marine environments. Mar Pollut Bull 2018; 127:396-405. [PMID: 29475677 DOI: 10.1016/j.marpolbul.2017.12.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 12/09/2017] [Accepted: 12/12/2017] [Indexed: 06/08/2023]
Abstract
Using 13C/12C, 15N/14N and 18O/16O isotopes, the trophic relationship and growth estimation were analyzed in gastropods Nassarius siquijorensis, Murex trapa and Turritella bacillum and their potential food sources and predators in summer and winter from estuarine and oceanic environments in subtropical Hong Kong. Results of δ13C and δ15N values and isotopic mixing model revealed N. siquijorensis and M. trapa were one trophic level higher than T. bacillum, in which its main food source was particulate organic matter (POM) whereas N. siquijorensis largely consumed POM and polychaetes and M. trapa also preyed on other gastropods. Crabs were the major predator of gastropods. Organisms collected from oceanic waters were more 13C enriched than from estuarine waters, reflecting different carbon food sources from marine or terrestrial origin. The δ18O profile from shell carbonate suggested these gastropods were one to two years old. T. bacillum exhibited faster summer growth than the other two species.
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Affiliation(s)
- Billy K Y Kwan
- Guangxi Key Laboratory of Beibu Gulf Marine Biodiversity Conservation, Qinzhou University, China; College of Ocean, Qinzhou University, China; Department of Biology and Chemistry, City University of Hong Kong, China
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, China; State Key Laboratory in Marine Pollution, City University of Hong Kong, China
| | - Alice K Y Chan
- Department of Biology and Chemistry, City University of Hong Kong, China
| | - Paul K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, China; State Key Laboratory in Marine Pollution, City University of Hong Kong, China.
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21
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Li F, Shi J, Cheung SG, Shin PKS, Liu X, Sun Y, Mu F. The combined effects of elevated pCO 2 and food availability on Tigriopus japonicus Mori larval development, reproduction, and superoxide dismutase activity. Mar Pollut Bull 2018; 126:623-628. [PMID: 28365018 DOI: 10.1016/j.marpolbul.2017.02.054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 02/16/2017] [Accepted: 02/22/2017] [Indexed: 06/07/2023]
Abstract
Previous studies have shown that ocean acidification has little effect on adult Tigriopus japonicus copepods, and mainly impairs the early development and reproduction of females. This study investigated the possible interactive effect between CO2-induced seawater acidification and food availability on larval development and reproductive output in T. japonicus. Copepods were exposed to either pH8.1 or pH7.3 under different food concentrations (0.5×104-80.0×104cells/mL). Both the development of nauplii and copepodites was delayed at pH7.3 with a greater effect at lower food concentrations. The reproductive output followed a bell-shaped curve with the highest reproductive output at food concentrations between 30×104 and 40×104cells/mL. As an indicator of oxidative stress, the activity of superoxide dismutase increased at lower pH, with a greater increase at lower food concentrations. Therefore, the effect of elevated pCO2 on T. japonicus was food dependent.
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Affiliation(s)
- Fei Li
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Jiahui Shi
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - P K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - Xiaoshou Liu
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Yan Sun
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Fanghong Mu
- College of Marine Life Sciences, Ocean University of China, Qingdao, China.
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Li FL, Yang L, Zan QJ, Shin PKS, Cheung SG, Wong YS, Tam NFY, Lei AP. Does energetic cost for leaf construction in Sonneratia change after introduce to another mangrove wetland and differ from native mangrove plants in South China? Mar Pollut Bull 2017; 124:1071-1077. [PMID: 28245937 DOI: 10.1016/j.marpolbul.2017.02.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 02/14/2017] [Accepted: 02/22/2017] [Indexed: 05/23/2023]
Abstract
Exotic species invasions are serious ecological problems. Leaf construction cost (CC) and growth traits of two Sonneratia (Sonneratia caseolaris and S. apetala) and four native species (Bruguiera gymnorrhiza, Kandelia obovata, Aegiceras corniculatum and Avicennia marina) in Hainan and Shenzhen mangrove wetlands were compared to evaluate invasive potentials of Sonneratia after introduced to Shenzhen, their new habitat. There were no significant differences in CC and growth traits between two wetlands, suggesting Sonneratia did not lose any advantage in the new habitat and were competitive in both wetlands. CC per unit mass (CCM), CC per unit area (CCA) and caloric values of Sonneratia were significantly lower than those of native mangrove species while specific leaf area (SLA) was just the opposite. CCM of S. caseolaris and S. apetala were 6.1% and 11.9% lower than those of natives, respectively. These findings indicated the invasive potential of Sonneratia in Shenzhen after their introduction.
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Affiliation(s)
- Feng-Lan Li
- College of Bio and Marine Sciences, Shenzhen Key Laboratory of Marine Bioresource and Eco-environmental Science, Shenzhen University, Shenzhen, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, SAR, China
| | - Lei Yang
- College of Bio and Marine Sciences, Shenzhen Key Laboratory of Marine Bioresource and Eco-environmental Science, Shenzhen University, Shenzhen, China
| | - Qi-Jie Zan
- Guangdong Neilingding Futian National Nature Reserve, Shenzhen, China
| | - Paul-K S Shin
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, SAR, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, SAR, China
| | - Siu-Gin Cheung
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, SAR, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, SAR, China
| | - Yuk-Shan Wong
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, SAR, China; School of Science and Technology, Open University of Hong Kong, Hong Kong, SAR, China
| | - Nora Fung-Yee Tam
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Hong Kong, SAR, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, SAR, China.
| | - An-Ping Lei
- College of Bio and Marine Sciences, Shenzhen Key Laboratory of Marine Bioresource and Eco-environmental Science, Shenzhen University, Shenzhen, China.
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Xu XY, Lee WT, Chan AKY, Lo HS, Shin PKS, Cheung SG. Microplastic ingestion reduces energy intake in the clam Atactodea striata. Mar Pollut Bull 2017; 124:798-802. [PMID: 28038767 DOI: 10.1016/j.marpolbul.2016.12.027] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 11/29/2016] [Accepted: 12/11/2016] [Indexed: 05/27/2023]
Abstract
The effects of microplastic concentrations (10itemsl-1 and 1000itemsl-1) on the physiological responses of Atactodea striata (clearance rate, absorption efficiency, respiration rate) were investigated. The fates of ingested microplastics and the efficiency of depuration in removing ingested microplastics were also studied. A. striata ingested microplastics and the clearance rate was reduced at high concentration of microplastics. Since the respiration rate and absorption efficiency remained unchanged in exposed A. striata, reduction in the clearance rate would reduce the energy intake. Ingestion and retention of microplastics in the body were further limited by the production of pseudofaeces and faeces, and depuration in clean water, resulting in a very small amount of microplastics stored in the body of the clam.
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Affiliation(s)
- X-Y Xu
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - W T Lee
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - A K Y Chan
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - H S Lo
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - P K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
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Tian T, Tam NFY, Zan Q, Cheung SG, Shin PKS, Wong YS, Zhang L, Chen Z. Performance and bacterial community structure of a 10-years old constructed mangrove wetland. Mar Pollut Bull 2017; 124:1096-1105. [PMID: 28711288 DOI: 10.1016/j.marpolbul.2017.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 06/30/2017] [Accepted: 07/03/2017] [Indexed: 06/07/2023]
Abstract
Constructed mangrove wetland has been used for wastewater treatment but its long-term performance has not been reported. One-year monitoring of a 10-years old horizontal subsurface-flow constructed mangrove wetland consisting of three belts, two with mangrove plants and one without, revealed that the system maintained high and stable removal percentages of organic matter and nutrients, and planted belts performed better than unplanted control. Substrates in belts planted with Aegiceras corniculatum or Kandelia obovata had higher abundance of ammonifiers, nitrifiers and denitrifiers but lower total heterotrophic bacteria than unplanted substrate. Denaturing gradient gel electrophoresis showed that microbial diversity in planted substrate was significantly lower than that in unplanted one. The bacteria in substrates, irrespective to belts, were phylogenetically related to Proteobacteria (most dominant), Acidobacteria, Firmicutes, Nitrospirae, Gemmatimonadetes, Chloroflexi and Cyanobacteria. The steady performance of this 10-year old constructed mangrove wetland was affected by the abundance and diversity of bacterial community in substrate.
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Affiliation(s)
- Tingting Tian
- Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, College of Life Science, South China Normal University, Guangzhou, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Shenzhen, China
| | - Nora F Y Tam
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Shenzhen, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China.
| | - Qijie Zan
- Guangdong Neilingding Futian National Nature Reserve, Shenzhen, China
| | - S G Cheung
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Shenzhen, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - Paul K S Shin
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Shenzhen, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - Y S Wong
- School of Science and Technology, Open University of Hong Kong, Hong Kong, China
| | - Li Zhang
- Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, College of Life Science, South China Normal University, Guangzhou, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Shenzhen, China
| | - Zhanghe Chen
- Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, College of Life Science, South China Normal University, Guangzhou, China.
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Wei P, Zan Q, Tam NFY, Shin PKS, Cheung SG, Li M. Impact of habitat management on waterbirds in a degraded coastal wetland. Mar Pollut Bull 2017; 124:645-652. [PMID: 28274473 DOI: 10.1016/j.marpolbul.2017.02.068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 02/21/2017] [Accepted: 02/24/2017] [Indexed: 06/06/2023]
Abstract
The loss of coastal wetlands in Hong Kong Mai Po Nature Reserve adversely affected wetland-depended species. To mitigate this impact, gei wai ponds were reconstructed according to a set of biodiversity management zones (BMZs). This study, based on Canonical Correspondence Analysis (CCA), investigated if waterbird distribution was related to BMZ characteristics. Based on habitat characteristics, ponds in the same BMZ generally clumped in the same quadrant or within a short distance on CCA scatter plots, indicating that a BMZ zone produced common habitat traits. Ponds in a close distance on the plot had similar bird abundance or community structure. Significant correlations were noted between the abundance of cormorants and tall tree, and between waders and bare ground areas within study ponds. This study indicated that the control of key habitat factors was important for the success of reconstruction of gei wais and management of waterbirds in Mai Po.
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Affiliation(s)
- Pingping Wei
- Life Sciences School of Sun Yat-sen University, Guangzhou, China; Futian-CityU Mangrove Research and Development Centre, Shenzhen, China
| | - Qijie Zan
- Neilingding-Futian National Nature Reserve of Guangdong, Shenzhen, China; College of Life Sciences Shenzhen University, Shenzhen, China
| | - Nora F Y Tam
- Futian-CityU Mangrove Research and Development Centre, Shenzhen, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China.
| | - Paul K S Shin
- Futian-CityU Mangrove Research and Development Centre, Shenzhen, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - S G Cheung
- Futian-CityU Mangrove Research and Development Centre, Shenzhen, China; Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - Mingguang Li
- Life Sciences School of Sun Yat-sen University, Guangzhou, China.
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Xu XY, Yip KR, Shin PKS, Cheung SG. Predator-prey interaction between muricid gastropods and mussels under ocean acidification. Mar Pollut Bull 2017; 124:911-916. [PMID: 28088370 DOI: 10.1016/j.marpolbul.2017.01.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 12/28/2016] [Accepted: 01/02/2017] [Indexed: 06/06/2023]
Abstract
Predation of the muricid gastropod Thais clavigera on two-sized groups of the mussel Brachidontes variabilis was studied under three pCO2 levels, 380, 950, and 1250μatm. At 950μatm pCO2 level, the prey handling time decreased significantly and large-sized B. variabilis were preferred by T. clavigera. However, the prey consumption rate was independent of pCO2 levels, although the prey searching time increased significantly at elevated pCO2. These findings indicated that the predator-prey interaction between T. clavigera and B. variabilis was altered under ocean acidification, which will have a long-term impact on the population dynamics of the interacting species.
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Affiliation(s)
- X-Y Xu
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - K R Yip
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - P K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; The State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; The State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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27
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Li FL, Zan QJ, Hu ZY, Shin PKS, Cheung SG, Wong YS, Tam NFY, Lei AP. Are Photosynthetic Characteristics and Energetic Cost Important Invasive Traits for Alien Sonneratia Species in South China? PLoS One 2016; 11:e0157169. [PMID: 27286250 PMCID: PMC4902315 DOI: 10.1371/journal.pone.0157169] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 05/25/2016] [Indexed: 11/29/2022] Open
Abstract
A higher photosynthesis and lower energetic cost are recognized as important characteristics for invasive species, but whether these traits are also important for the ability of alien mangrove species to become invasive has seldom been reported. A microcosm study was conducted to compare the photosynthetic characteristics, energetic cost indices and other growth traits between two alien species (Sonneratia apetala and S. caseolaris) and four native mangrove species over four seasons in a subtropical mangrove nature reserve in Shenzhen, South China. The aim of the study was to evaluate the invasive potential of Sonneratia based on these physiological responses. The annual average net photosynthetic rate (Pn), stomatal conductance (Gs) and total carbon assimilation per unit leaf area (Atotal) of the two alien Sonneratia species were significantly higher than the values of the native mangroves. In contrast, the opposite results were obtained for the leaf construction cost (CC) per unit dry mass (CCM) and CC per unit area (CCA) values. The higher Atotal and lower CC values resulted in a 72% higher photosynthetic energy-use efficiency (PEUE) for Sonneratia compared to native mangroves, leading to a higher relative growth rate (RGR) of the biomass and height of Sonneratia with the respective values being 51% and 119% higher than those of the native species. Higher photosynthetic indices for Sonneratia compared to native species were found in all seasons except winter, whereas lower CC values were found in all four seasons. The present findings reveal that alien Sonneratia species may adapt well and become invasive in subtropical mangrove wetlands in Shenzhen due to their higher photosynthetic characteristics coupled with lower costs in energy use, leading to a higher PEUE. The comparison of these physiological responses between S. apetala and S. caseolaris reveal that the former species is more invasive than the latter one, thus requiring more attention in future.
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Affiliation(s)
- Feng-Lan Li
- College of Life Sciences, Shenzhen University, Shenzhen, China
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
| | - Qi-Jie Zan
- Guangdong Neilingding Futian National Nature Reserve, Shenzhen, China
| | - Zheng-Yu Hu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Paul-K. S. Shin
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
| | - Siu-Gin Cheung
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
| | - Yuk-Shan Wong
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
- School of Science and Technology, Open University of Hong Kong, Homantin, Kowloon, Hong Kong SAR, China
| | - Nora Fung-Yee Tam
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
- * E-mail: (NFYT); (APL)
| | - An-Ping Lei
- College of Life Sciences, Shenzhen University, Shenzhen, China
- * E-mail: (NFYT); (APL)
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Zhang H, Shin PKS, Cheung SG. Physiological responses and scope for growth upon medium-term exposure to the combined effects of ocean acidification and temperature in a subtidal scavenger Nassarius conoidalis. Mar Environ Res 2015; 106:51-60. [PMID: 25771491 DOI: 10.1016/j.marenvres.2015.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 02/23/2015] [Accepted: 03/01/2015] [Indexed: 06/04/2023]
Abstract
Physiological responses (ingestion rate, absorption rate and efficiency, respiration, rate, excretion rate) and scope for growth of a subtidal scavenging gastropod Nassarius conoidalis under the combined effects of ocean acidification (pCO2 levels: 380, 950, 1250 μatm) and temperature (15, 30 °C) were investigated for 31 days. There was a significant reduction in all the physiological rates and scope for growth following short-term exposure (1-3 days) to elevated pCO2 except absorption efficiency at 15 °C and 30 °C, and respiration rate and excretion rate at 15 °C. The percentage change in the physiological rates ranged from 0% to 90% at 15 °C and from 0% to 73% at 30 °C when pCO2 was increased from 380 μatm to 1250 μatm. The effect of pCO2 on the physiological rates was enhanced at high temperature for ingestion, absorption, respiration and excretion. When the exposure period was extended to 31 days, the effect of pCO2 was significant on the ingestion rate only. All the physiological rates remained unchanged when temperature increased from 24 °C to 30 °C but the rates at 15 °C were significantly lower, irrespective of the duration of exposure. Our data suggested that a medium-term exposure to ocean acidification has no effect on the energetics of N. conoidalis. Nevertheless, the situation may be complicated by a longer term of exposure and/or a reduction in salinity in a warming world.
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Affiliation(s)
- Haoyu Zhang
- Department of Biology and Chemistry, 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
| | - 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.
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Xu HM, Tam NFY, Zan QJ, Bai M, Shin PKS, Vrijmoed LLP, Cheung SG, Liao WB. Effects of salinity on anatomical features and physiology of a semi-mangrove plant Myoporum bontioides. Mar Pollut Bull 2014; 85:738-46. [PMID: 24768170 DOI: 10.1016/j.marpolbul.2014.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 03/22/2014] [Accepted: 04/01/2014] [Indexed: 05/06/2023]
Abstract
The effect of different concentrations of NaCl, 0, 100, 200, 300 and 400 mM, on the anatomical features and physiology of Myoporum bontioides was investigated. The photosynthetic rates (Pn) were significantly reduced by salt stress, with the lowest values at 400 mM NaCl. The content of malondialdehyde (MDA), proline and soluble sugar, as well as the activities of peroxidase (POD) and catalase (CAT) increased at the beginning, but became similar to the control as the experiment proceeded. The NaCl effect on superoxide dismutase (SOD) was different from the other parameters, with a significant reduction at 400 mM NaCl at Day 7. Salt glands were found in both upper and lower epidermis, and the ratios of the thickness of palisade to spongy mesophyll tissues increased with NaCl concentrations. The medullary ray was clearly damaged by NaCl at levels of 200 and 300 mM. These results demonstrated that M. bontioides could adapt to a relatively low salinity, and was not a halophilous species.
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Affiliation(s)
- H M Xu
- Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - N F Y Tam
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region.
| | - Q J Zan
- Shenzhen Wildlife Rescue and Rehabilitation Center, Xinzhou Road, Shenzhen 518048, China
| | - M Bai
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - P K S Shin
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - L L P Vrijmoed
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - S G Cheung
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - W B Liao
- Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
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Yang Q, Lei AP, Li FL, Liu LN, Zan QJ, Shin PKS, Cheung SG, Tam NFY. Structure and function of soil microbial community in artificially planted Sonneratia apetala and S. caseolaris forests at different stand ages in Shenzhen Bay, China. Mar Pollut Bull 2014; 85:754-63. [PMID: 24629377 DOI: 10.1016/j.marpolbul.2014.02.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 02/14/2014] [Accepted: 02/19/2014] [Indexed: 05/26/2023]
Abstract
The present study examined the relationships between soil characteristics, microbial community structure and function in the forests artificially planted with exotic Sonneratia apetala at stand ages of 1-, 2-, 7-, 10- and 14-years and Sonneratia caseolaris of 1-, 4-, 7-, 10- and 14-years in Futian National Nature Reserve, Shenzhen Bay, China. The 7-years old forests of both Sonneratia species reached peak growth and had the highest content of nitrogen and phosphorus, enzymatic activities, including dehydrogenase, cellulase, phosphatase, urease and ß-glucosidase, except arylsulphatase which increased continuously with stand ages. The microbial community structure reflected by phospholipid fatty acid (PLFA) profiles also reached the maximum value in the 7-years old forests and soil bacterial PLFAs in both forests were significantly higher than fungal PLFAs. The canonical correlation analysis revealed that differences in microbial structural variables were significantly correlated to the differences in their functional variables, and the highest correlation was found between the soil enzymatic activities and the content of carbon and nitrogen.
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Affiliation(s)
- Q Yang
- Guangdong Neilingding Futian National Nature Reserve, Shenzhen 518040, China; Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - A P Lei
- College of Life Sciences, Shenzhen University, Shenzhen 518060, China
| | - F L Li
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; College of Life Sciences, Shenzhen University, Shenzhen 518060, China
| | - L N Liu
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Shenzhen Wild Animal Rescue Center, Xinzhou Road, Shenzhen 518048, China
| | - Q J Zan
- Shenzhen Wild Animal Rescue Center, Xinzhou Road, Shenzhen 518048, China
| | - P K S Shin
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - S G Cheung
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region
| | - N F Y Tam
- Futian-CityU Mangrove Research and Development Centre, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region; Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region.
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Shin PKS, Leung JYS, Qiu JW, Ang PO, Chiu JMY, Thiyagarajan V, Cheung SG. Acute hypoxic exposure affects gamete quality and subsequent fertilization success and embryonic development in a serpulid polychaete. Mar Pollut Bull 2014; 85:439-445. [PMID: 24661460 DOI: 10.1016/j.marpolbul.2014.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Revised: 02/28/2014] [Accepted: 03/02/2014] [Indexed: 06/03/2023]
Abstract
Hypoxia likely compromises the reproductive success of those marine organisms carrying out external fertilization because their gametes and embryos are inevitably exposed to the external environment. Hydroides elegans, a dominant serpulid polychaete in Hong Kong waters, can spawn throughout the year but the number of recruits drops during summer when hypoxia commonly occurs. This study attempted to explain such observation by investigating the gamete quality, including sperm motility, egg size, complexity and viability, after 1-h hypoxic exposure (1 mg O2 l(-1)). In addition, how gamete quality affects fertilization success and embryonic development was examined. After 1-h hypoxic exposure, sperm motility was significantly reduced, compromising fertilization success. Although the eggs remained viable, more malformed embryos and retarded embryonic development were observed. We interpreted that the harmful effect of hypoxia on embryonic development was attributed to the teratogenicity and induced oxidative stress, ultimately causing the reduction in recruitment during summer.
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Affiliation(s)
- P 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
| | - J Y S Leung
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
| | - J W Qiu
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - P O Ang
- School of Life Sciences, Chinese University of Hong Kong, New Territories, Hong Kong, China
| | - J M Y Chiu
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - V Thiyagarajan
- School of Biological Sciences, The University of Hong Kong, Pokfulam, 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.
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Cheung SG, Chan CYS, Po BHK, Li AL, Leung JYS, Qiu JW, Ang PO, Thiyagarajan V, Shin PKS, Chiu JMY. Effects of hypoxia on biofilms and subsequently larval settlement of benthic invertebrates. Mar Pollut Bull 2014; 85:418-424. [PMID: 24855975 DOI: 10.1016/j.marpolbul.2014.04.051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Revised: 04/28/2014] [Accepted: 04/30/2014] [Indexed: 06/03/2023]
Abstract
Biofilms on submerged surfaces are important in determining larval settlement of most marine benthic invertebrates. We investigated if exposure of biofilms to hypoxia would alter the larval settlement pattern and result in a shift in benthic invertebrate community structure in the field. Biofilms were first exposed to hypoxia or normoxia in laboratory microcosms for 7 days, and then deployed in the field for another 7 days to allow for larval settlement and recruitment to occur. Using terminal-restriction fragment length polymorphism of the 16S rRNA gene, this study showed that hypoxia altered the biofilm bacterial community composition, and the difference between the hypoxic and normoxic treatments increased with the time of exposure period. This study also demonstrated significantly different benthic invertebrate community structures as a result of biofilm exposure to hypoxia and that the hypoxic and normoxic treatments were dominated by Hydroides sp. and Folliculina sp., respectively.
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Affiliation(s)
- S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - C Y S Chan
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - B H K Po
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - A L Li
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - J Y S Leung
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - J W Qiu
- Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong
| | - P O Ang
- School of Life Sciences, The Chinese University of Hong Kong, New Territories, Hong Kong
| | - V Thiyagarajan
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - P K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - J M Y Chiu
- Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong.
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Shin PKS, Chan CSK, Cheung SG. Physiological energetics of the fourth instar of Chinese horseshoe crabs (Tachypleus tridentatus) in response to hypoxic stress and re-oxygenation. Mar Pollut Bull 2014; 85:522-525. [PMID: 24215995 DOI: 10.1016/j.marpolbul.2013.10.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/09/2013] [Accepted: 10/15/2013] [Indexed: 06/02/2023]
Abstract
Hypoxia associated with eutrophication is a potential threat to the Chinese horseshoe crab Tachypleus tridentatus which inhabits intertidal sand flats in Asia. This study investigated the effect of dissolved oxygen level (DO) (6, 4 and 2 mg O2 l(-1)) on the physiological energetics in the juvenile T. tridentatus. They were exposed to various oxygen levels for three days and then transferred to normoxia for three days to examine the recovery from low oxygen stress. Feeding rate, respiration rate and scope for growth were reduced at lower DO levels while absorption efficiency and excretion rate were independent of DO levels. Although full recovery of the physiological responses and scope for growth from hypoxis stress was observed when normoxia resumed, their long term survival in suboptimal habitats with frequent occurrence of hypoxia deserves a close monitoring as hypoxia may be even more common in future in a warming world.
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Affiliation(s)
- Paul K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong
| | - Cathy S K Chan
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong.
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Xu WZ, Cheung SG, Shin PKS. Structure and taxonomic composition of free-living nematode and macrofaunal assemblages in a eutrophic subtropical harbour, Hong Kong. Mar Pollut Bull 2014; 85:764-773. [PMID: 24467853 DOI: 10.1016/j.marpolbul.2014.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 12/24/2013] [Accepted: 01/07/2014] [Indexed: 06/03/2023]
Abstract
The spatial and seasonal taxonomic composition patterns of macrofauna and nematodes in a eutrophic subtropical harbour, previously suffered from sewage pollution, were studied in relation to a number of sediment parameters. In the polluted, inner-harbour area, levels of organic contents and heavy metals were high, whereas species number, abundance and diversity of nematodes and macrofauna were the lowest in comparison to the cleaner, outer-harbour area. Different taxonomic composition patterns of nematodes and macrofaunal assemblages were found between inner-harbour and outer-harbour area, which was highly correlated with sediment nutrient levels. Different responses of macrofaunal and nematode communities to sewage pollution suggested that macrofauna might be more tolerant than nematodes to eutrophic conditions due to their ability to modify the sediment. The present findings indicated the usefulness of studying both nematode and macrofaunal communities, in order to reveal different aspects of the benthic ecosystems in response to organic enrichment.
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Affiliation(s)
- W Z Xu
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong
| | - Paul K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong.
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Liu CC, Shin PKS, Cheung SG. Isolation and mRNA expression of hypoxia-inducible factor α (HIF-α) in two sublittoral nassariid gastropods: Nassarius siquijorensis and Nassarius conoidalis. Mar Environ Res 2014; 99:44-51. [PMID: 24980608 DOI: 10.1016/j.marenvres.2014.05.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 05/26/2014] [Accepted: 05/28/2014] [Indexed: 06/03/2023]
Abstract
Hypoxia-inducible factor (HIF) is commonly found in vertebrates as an adaptation against hypoxia. In this study, partial sequences of HIF were first reported for subtidal nassariid gastropods, Nassarius siquijorensis and Nassarius conoidalis. The phylogenetic tree of HIF-α among various animal groups was inferred. Adults of both N. siquijorensis and N. conoidalis were exposed to 24 h and 1 week hypoxia (1.5 mg O2 l(-1)) and the change of HIF-α mRNA level was determined in gill, foot muscle and hepatopancreas by using quantitative real-time PCR. The expression profile of HIF-α was also investigated in veliger larvae after 1 and 24 h hypoxia exposure. The HIF-α mRNA from gills of N. siquijorensis was 2.22-fold elevated after 24 h of exposure but returned back to the baseline level after 1 week of exposure. In contrast to N. siquijorensis, both short-term and long-term exposure to hypoxia significantly enhanced the mRNA level of HIF-α in the gill of N. conoidalis. Both 24 h and 1 week of exposure resulted in a significantly higher degree of expression of mRNA of HIF-α in the foot muscle of N. siquijorensis and N. conoidalis. For hepatopancreas, the mRNA level of HIF-α remained unchanged in N. siquijorensis after both 24 h and 1 week of exposure to hypoxia but a significant enhancement was observed in N. conoidalis after 1 week of exposure to hypoxia. The mRNA level of HIF-α significantly reduced after 24 h of exposure to hypoxia in the larvae of N. siquijorensis. The different expression patterns of HIF-α mRNA between the two species reflected their different adaptation abilities to hypoxia, which will further explain the differences in the distribution of these species in Hong Kong waters with N. siquijorensis being predominant in regions suffered from summer hypoxia.
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Affiliation(s)
- C C Liu
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong.
| | - P K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong; State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong; State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong
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Liu CC, Shin PKS, Cheung SG. Comparisons of the metabolic responses of two subtidal nassariid gastropods to hypoxia and re-oxygenation. Mar Pollut Bull 2014; 82:109-116. [PMID: 24680715 DOI: 10.1016/j.marpolbul.2014.03.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 03/05/2014] [Accepted: 03/10/2014] [Indexed: 06/03/2023]
Abstract
Changes in the levels of carbohydrate, lipid, protein and anaerobic metabolites (succinate, lactate, acetate, fumarate and propionate), upon exposure to hypoxia (1.5 mg O2 l(-1)) and after reoxygenation in subtidal gastropods Nassarius siquijorensis and N. conoidalis, were compared. A significant decrease of the glycogen content was observed under hypoxia in N. conoidalis but not in N. siquijorensis. A greater increase in the concentrations of anaerobic metabolites was observed in N. conoidalis under hypoxia, and their levels did not return to baseline after returning to normoxia for 24h. In contrast, a lower rate of accumulation of the metabolites was observed in N. siquijorensis, and complete recovery from anaerobic metabolism was observed after reoxygenation. The results lend further support to the role of hypoxia in governing the different distributional patterns between the two subtidal gastropods in Hong Kong waters.
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Affiliation(s)
- C C Liu
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - P K S Shin
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong
| | - S G Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong.
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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. Mar Pollut Bull 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Shin PKS, Leung JYS, Qiu JW, Ang PO, Chiu JMY, Thiyagarajan V, Cheung SG. Hypoxia induces abnormal larval development and affects biofilm-larval interaction in the serpulid polychaete Hydroides elegans. Mar Pollut Bull 2013; 76:291-297. [PMID: 24050126 DOI: 10.1016/j.marpolbul.2013.08.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 08/16/2013] [Accepted: 08/20/2013] [Indexed: 06/02/2023]
Abstract
Hydroides elegans, a worldwide fouling polychaete, can spawn throughout the year, but its recruitment drops during summer when hypoxia prevails. Here, the influence of hypoxia on larval development and settlement of H. elegans was investigated. Results showed that larval development was compromised at 1mg O2 l(-1) with a lower proportion of competent larvae and a higher proportion of malformed larvae, probably due to reduction in clearance rate. Regarding larval settlement, although most of the larvae were reluctant to settle at 1mg O2 l(-1), regardless of the biofilm nature, they settled quickly within 24h in response to the resumption of dissolved oxygen. Furthermore, only about 5% of the larvae settled on the biofilms developed under hypoxia, regardless of dissolved oxygen levels of the seawater. The delayed larval development and potential alteration of biofilm nature owing to hypoxia explained why the recruitment of H. elegans declines during summer.
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Affiliation(s)
- P 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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Leung JYS, Cheung SG, Qiu JW, Ang PO, Chiu JMY, Thiyagarajan V, Shin PKS. Effect of parental hypoxic exposure on embryonic development of the offspring of two serpulid polychaetes: Implication for transgenerational epigenetic effect. Mar Pollut Bull 2013; 74:149-155. [PMID: 23906470 DOI: 10.1016/j.marpolbul.2013.07.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 06/30/2013] [Accepted: 07/04/2013] [Indexed: 06/02/2023]
Abstract
Sperm production and motility, fecundity, and egg size, complexity and viability of serpulid polychaetes Hydroides elegans and Hydroides diramphus after 2-week treatment to hypoxia (2 mg O2 l(-1)) was compared with those under normoxia (6 mg O2 l(-1)). Despite reduced fecundity, the effect of parental hypoxic exposure on gamete quality was not discernible for both species. However, regardless of their subsequent dissolved oxygen environment, eggs spawned by H. elegans after hypoxic exposure were found to have lower fertilization success, slower embryonic development and a significantly higher yield of malformed embryos than those with a parental normoxic treatment. In contrast, neither fertilization success nor rate of embryonic development was affected for H. diramphus. The results implied that hypoxia was a potential stress reducing the recruitment of H. elegans through non-adaptive epigenetic effect, whereas H. diramphus was a more tolerant species to survive hypoxic events.
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Affiliation(s)
- J Y S Leung
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong, China
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Chen Y, Cheung SG, Shin PKS. A baseline study of benthic community associated with Amphioxus Sand in subtropical Hong Kong. Mar Pollut Bull 2013; 72:274-280. [PMID: 23622836 DOI: 10.1016/j.marpolbul.2013.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 03/15/2013] [Indexed: 06/02/2023]
Abstract
An annual investigation on the seasonal changes of benthic community structure associated with Amphioxus Sand was conducted at two sites in the eastern waters of subtropical Hong Kong, where three species of amphioxus, Branchiostoma belcheri, B. japonicum and B. malayanum coexist. A total of 84 species and 4169 individuals were recorded at Tai Long Wan, whereas a total of 87 species and 3915 individuals were recorded at Pak Lap Wan. Benthic polychaetes were dominant, including high abundance of Onuphis eremita and Prionospio malmgreni. Results of cluster analysis showed significant community structures between the two areas because of difference in sediment granulometry. However, temporal changes within these Amphioxus Sand communities were minimal. In general, the Amphioxus Sand communities in Hong Kong showed higher species richness of Polychaeta as compared with similar studies elsewhere, possibly implying an increased level of organic pollution in Hong Kong waters.
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Affiliation(s)
- Y Chen
- Department of Biology and Chemistry and State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong
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Wang Y, Hu M, Cheung SG, Shin PKS, Lu W, Li J. Chronic hypoxia and low salinity impair anti-predatory responses of the green-lipped mussel Perna viridis. Mar Environ Res 2012; 77:84-89. [PMID: 22405812 DOI: 10.1016/j.marenvres.2012.02.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 02/11/2012] [Accepted: 02/14/2012] [Indexed: 05/31/2023]
Abstract
The effects of chronic hypoxia and low salinity on anti-predatory responses of the green-lipped mussel Perna viridis were investigated. Dissolved oxygen concentrations ranged from hypoxic to normoxic (1.5 ± 0.3 mg l(-1), 3.0 ± 0.3 mg l(-1) and 6.0 ± 0.3 mg l(-1)), and salinities were selected within the variation during the wet season in Hong Kong coastal waters (15‰, 20‰, 25‰ and 30‰). The dissolved oxygen and salinity significantly affected some anti-predatory responses of mussel, including byssus production, shell thickness and shell weight, and the adductor diameter was only significantly affected by salinity. Besides, interactive effects of dissolved oxygen and salinity on the byssus production and shell thickness were also observed. In hypoxic and low salinity conditions, P. viridis produced fewer byssal threads, thinner shell and adductor muscle, indicating that hypoxia and low salinity are severe environmental stressors for self-defence of mussel, and their interactive effects further increase the predation risk.
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Affiliation(s)
- Youji Wang
- College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, Shanghai 201306, China.
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Wang Y, Hu M, Chiang MWL, Shin PKS, Cheung SG. Characterization of subpopulations and immune-related parameters of hemocytes in the green-lipped mussel Perna viridis. Fish Shellfish Immunol 2012; 32:381-390. [PMID: 21982876 DOI: 10.1016/j.fsi.2011.08.024] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 08/30/2011] [Accepted: 08/30/2011] [Indexed: 05/31/2023]
Abstract
The green-lipped mussel Perna viridis is distributed widely in the estuarine and coastal areas of the Indo-Pacific region and extensively cultured as an inexpensive protein source. Morphology and immunological activities of hemocytes of P. viridis were investigated using flow cytometry and light and electron microscopy. Three major types of hemocytes were identified in the hemolymph, including dense-granulocyte, semi-granulocyte (small and large size) and hyalinocyte. Other hemocytes, which occurred in low numbers, included granulocytes with different electron-dense/lucent granules and hemoblast-like cells. Based on flow cytometry, two subpopulations were identified. Granulocytes were larger cells, and the more abundant, containing numerous granules in the cytoplasm, and hyalinocytes were the smaller and less abundant with the fewest granules. Flow cytometry revealed that the granulocytes were more active in cell phagocytosis, contained the higher lysosomal content, and showed higher esterase activity and reactive oxygen species (ROS) generation compared with hyalinocytes. Immune functions assessed by the flow cytometry indicated that the granulocytes were the main hemocytes involved in the cellular defence in P. viridis.
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Affiliation(s)
- Youji Wang
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
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Li F, Yang Q, Zan Q, Tam NFY, Shin PKS, Vrijmoed LLP, Cheung SG. Differences in leaf construction cost between alien and native mangrove species in Futian, Shenzhen, China: implications for invasiveness of alien species. Mar Pollut Bull 2011; 62:1957-1962. [PMID: 21774949 DOI: 10.1016/j.marpolbul.2011.06.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 06/22/2011] [Accepted: 06/26/2011] [Indexed: 05/31/2023]
Abstract
Construction cost (CC) is a quantifiable measure of energy demand for biomass production, and low CC is hypothesized to give an alien plant growth advantages and increase its potential to be an invader. Comparison of leaf CC and growth traits between alien and native mangroves in Shenzhen Futian Nature Reserve showed CC per unit mass (CC(mass)), carbon concentration and gross and ash-free caloric values of alien mangroves were significantly lower than those of native species, while the height and chest circumference were just the opposite. Alien species Sonneratia apetala had the lowest CC(mass) while Sonneratia caseolaris had the lowest CC(area), and were 8.99% and 32.17% lower than those of native species, respectively. Conversely, specific leaf area (SLA) of these two Sonneratia species was significantly higher than native species. Lower CC and higher SLA make the two Sonneratia species grow and spread faster than other mangroves and enhance their invasive potential.
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Affiliation(s)
- Fenglan Li
- Futian-CityU Mangrove Research and Development Centre, Futian National Nature Reserve, Mangrove Road, Shenzhen 518040, China
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Wai TC, Leung KMY, Wu RSS, Shin PKS, Cheung SG, Li XY, Lee JHW. Stable isotopes as a useful tool for revealing the environmental fate and trophic effect of open-sea-cage fish farm wastes on marine benthic organisms with different feeding guilds. Mar Pollut Bull 2011; 63:77-85. [PMID: 21641622 DOI: 10.1016/j.marpolbul.2011.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2010] [Revised: 05/03/2011] [Accepted: 05/04/2011] [Indexed: 05/30/2023]
Abstract
Environmental fate of fish farm wastes (FFW) released from an open-sea-cage farm at Kat O, Hong Kong was examined by measuring carbon and nitrogen stable isotope (SI) ratios in selected benthic organisms collected along a 2000 m transect from the farm. Our results showed that FFW significantly influenced the energy utilization profile of consumers near the fish farm. Although nitrogen enrichment effect on δ15N was anticipated in biota near the farm, the predicted patterns did not consistently occur in all feeding guilds. Two species of suspension-feeders, which relied on naturally δ15N-depleted sources, were δ15N-enriched near the fish farm. In contrast, both species of benthic grazer and deposit-feeder, which relied on naturally δ15N-enriched algal sources, were δ15N-depleted under the influence of FFW. The SI signatures of biota can, therefore, serve as feasible biomarkers for FFW discharges only when the trophic structure of the receiving environment is fully elucidated.
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Affiliation(s)
- Tak-Cheung Wai
- The Swire Institute of Marine Science and School of Biological Sciences, Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China.
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Fleddum A, Cheung SG, Hodgson P, Shin PKS. Impact of hypoxia on the structure and function of benthic epifauna in Tolo Harbour, Hong Kong. Mar Pollut Bull 2011; 63:221-229. [PMID: 21481897 DOI: 10.1016/j.marpolbul.2011.03.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Revised: 03/15/2011] [Accepted: 03/16/2011] [Indexed: 05/30/2023]
Abstract
In Tolo Harbour, Hong Kong, where hypoxia occurs periodically, a large amount of benthic epifauna was found to be absent in the summer but become abundant again in the winter. This observation may indicate that some species are sensitive in detecting low dissolved oxygen (DO) levels and are able to escape from the harbour to more oxygenated, open waters when conditions deteriorate and return when DO levels are improved. Analysis of biological traits of these animals showed that 58% of the categories showed significant differences between the community structure in summer and winter. The significant biological traits of the few species, which remained in the harbour under the summer's hypoxic conditions suggested adaptation rather than opportunism to the low DO levels. Our data also showed that trawling can increase DO at the bottom and may benefit the less sensitive species that remained in the habitat during the summer.
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Affiliation(s)
- A Fleddum
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
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Liu CC, Chiu JMY, Li L, Shin PKS, Cheung SG. Respiration rate and swimming activity of larvae of two sub-tidal nassariid gastropods under reduced oxygen levels: implications for their distributions in Hong Kong waters. Mar Pollut Bull 2011; 63:230-236. [PMID: 21453934 DOI: 10.1016/j.marpolbul.2011.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 01/19/2011] [Accepted: 03/09/2011] [Indexed: 05/30/2023]
Abstract
The effects of hypoxia on the larvae of two sub-tidal nassariid gastropods, Nassarius siquijorensis and N. conoidalis were compared so as to understand how the species-specific tolerance to hypoxia might have resulted in changes in the abundance and distribution of these two species in the hypoxic Tolo Harbour, Hong Kong, since the 1980s. Respiration rates of N. siquijorensis and N. conoidalis larvae were reduced at 4.5 mg O2 l(-1), or below, as compared with the normoxic control. Significant reduction in swimming velocity was also observed for 10-day old larvae which were exposed to <2.0 mg O2 l(-1) for N. siquijorensis and <1.0 mg O2 l(-1) for N. conoidalis. The 48 h LC50 values of N. siquijorensis and N. conoidalis larvae were 0.7 and 1.7 mg O2 l(-1), respectively. The results suggested that N. siquijorensis are more tolerant to hypoxia than N. conoidalis.
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Affiliation(s)
- C C Liu
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
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Liu XS, Xu WZ, Cheung SG, Shin PKS. Response of meiofaunal community with special reference to nematodes upon deployment of artificial reefs and cessation of bottom trawling in subtropical waters, Hong Kong. Mar Pollut Bull 2011; 63:376-84. [PMID: 21146838 DOI: 10.1016/j.marpolbul.2010.11.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2010] [Accepted: 11/25/2010] [Indexed: 05/16/2023]
Abstract
The response of meiofaunal communities, especially nematodes, upon the deployment of artificial reefs and cessation of bottom trawling at a designated Marine Protected Area (MPA) in Hong Kong was studied through comparison of meiofaunal samples collected inside and outside the MPA. Total organic carbon (TOC), total Kjeldahl nitrogen (TKN), total phosphorus (TP), water content and silt-clay fraction in sediments were also analyzed. The level of TOC and TKN, and total meiofaunal and nematode abundance were significantly lower inside than that outside the MPA. Multivariate analysis also indicated differences in community structure. Biological traits analysis revealed that the proportions of nematodes with a clavate tail shape, longer adult length, stout body shape and k-strategy life history were higher inside than that outside the MPA. Such changes in nematode community structure could be a result of the presence of the artificial reefs and closure of the MPA from bottom trawling.
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Affiliation(s)
- Xiao-Shou Liu
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
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Chiu JMY, Shin PKS, Wong KP, Cheung SG. Sibling Cannibalism in Juveniles of the Marine GastropodNassarius festivus(Powys, 1835). Malacologia 2010. [DOI: 10.4002/040.052.0109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Cheung SG, Wai HY, Zhou H, Shin PKS. Structure of infaunal macrobenthos in the presence of artificial reefs in subtropical Hong Kong. Mar Pollut Bull 2009; 58:934-939. [PMID: 19364612 DOI: 10.1016/j.marpolbul.2009.03.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2009] [Revised: 03/10/2009] [Accepted: 03/11/2009] [Indexed: 05/27/2023]
Affiliation(s)
- Siu-Gin Cheung
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong, China
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Liu XS, Cheung SG, Shin PKS. Meiofauna with special reference to nematodes in trawling ground of subtropical Hong Kong. Mar Pollut Bull 2009; 58:607-615. [PMID: 19187945 DOI: 10.1016/j.marpolbul.2009.01.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2008] [Revised: 12/24/2008] [Accepted: 01/06/2009] [Indexed: 05/27/2023]
Affiliation(s)
- Xiao-Shou Liu
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
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