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Yu C, Liu Y, Zhang Y, Shen MZ, Wang JH, Chi ZY. Seawater Chlorella sp. biofilm for mariculture effluent polishing under environmental combined antibiotics exposure and ecological risk evaluation based on parent antibiotics and transformation products. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 939:173643. [PMID: 38821282 DOI: 10.1016/j.scitotenv.2024.173643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/21/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
Mariculture effluent polishing with microalgal biofilm could realize effective nutrients removal and resolve the microalgae-water separation issue via biofilm scraping or in-situ aquatic animal grazing. Ubiquitous existence of antibiotics in mariculture effluents may affect the remediation performances and arouse ecological risks. The influence of combined antibiotics exposure at environment-relevant concentrations towards attached microalgae suitable for mariculture effluent polishing is currently lack of research. Results from suspended cultures could offer limited guidance since biofilms are richer in extracellular polymeric substances that may protect the cells from antibiotics and alter their transformation pathways. This study, therefore, explored the effects of combined antibiotics exposure at environmental concentrations towards seawater Chlorella sp. biofilm in terms of microalgal growth characteristics, nutrients removal, anti-oxidative responses, and antibiotics removal and transformations. Sulfamethoxazole (SMX), tetracycline (TL), and clarithromycin (CLA) in single, binary, and triple combinations were investigated. SMX + TL displayed toxicity synergism while TL + CLA revealed toxicity antagonism. Phosphorus removal was comparable under all conditions, while nitrogen removal was significantly higher under SMX and TL + CLA exposure. Anti-oxidative responses suggested microalgal acclimation towards SMX, while toxicity antagonism between TL and CLA generated least cellular oxidative damage. Parent antibiotics removal was in the order of TL (74.5-85.2 %) > CLA (60.8-69.5 %) > SMX (13.5-44.1 %), with higher removal efficiencies observed under combined than single antibiotic exposure. Considering the impact of residual parent antibiotics, CLA involved cultures were identified of high ecological risks, while medium risks were indicated in other cultures. Transformation products (TPs) of SMX and CLA displayed negligible aquatic toxicity, the parent antibiotics themselves deserve advanced removal. Four out of eight TPs of TL could generate chronic toxicity, and the elimination of these TPs should be prioritized for TL involved cultures. This study expands the knowledge of combined antibiotics exposure upon microalgal biofilm based mariculture effluent polishing.
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Affiliation(s)
- Chong Yu
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Yang Liu
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Ying Zhang
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Ming-Zhi Shen
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Jing-Han Wang
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China.
| | - Zhan-You Chi
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
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Wang S, Zhang C, Zhang K, Zhang L, Bi R, Zhang Y, Hu Z. One-step bioremediation of hypersaline and nutrient-rich food industry process water with a domestic microbial community containing diatom Halamphora coffeaeformis. WATER RESEARCH 2024; 254:121430. [PMID: 38461607 DOI: 10.1016/j.watres.2024.121430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 02/29/2024] [Accepted: 03/05/2024] [Indexed: 03/12/2024]
Abstract
Proper treatment of hypersaline and nutrient-rich food industry process water (FIPW) is challenging in conventional wastewater plants. Insufficient treatment leads to serious environmental hazards. However, bioremediation of FIPW with an indigenous microbial community can not only recover nutrients but generate biomass of diverse applications. In this study, monoculture of Halamphora coffeaeformis, together with synthetic bacteria isolated from a local wastewater plant, successfully recovered 91% of NH4+-N, 78% of total nitrogen, 95% of total phosphorus as well as 82% of total organic carbon from medium enriched with 10% FIPW. All identified organic acids and amino acids, except oxalic acid, were completely removed after 14 days treatment. A significantly higher biomass concentration (1.74 g L-1) was achieved after 14 days treatment in the medium with 10% FIPW than that in a nutrient-replete lab medium as control. The harvested biomass could be a potential feedstock for high-value biochemicals and fertilizer production, due to fucoxanthin accumulation (3 mg g-1) and a fantastic performance in P assimilation. Metagenomic analysis revealed that bacteria community in the algal system, dominated by Psychrobacter and Halomonas, also contributed to the biomass accumulation and uptake of nutrients. Transcriptomic analysis further disclosed that multiple pathways, involved in translation, folding, sorting and degradation as well as transport and catabolism, were depressed in H. coffeaeformis grown in FIPW-enriched medium, as compared to the control. Collectively, the proposed one-step strategy in this work offers an opportunity to achieve sustainable wastewater management and a way towards circular economy.
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Affiliation(s)
- Song Wang
- Guangdong Technology Research Center for Marine Algal Bioengineering, Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Longhua Innovation Institute for Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Chenzhi Zhang
- College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China
| | - Kai Zhang
- Chongqing Academy of Agricultural Sciences, Chongqing 401329, China
| | - Ling Zhang
- College of Horticulture and Landscape Architecture, Northeast Agricultural University, Harbin 150030, China
| | - Ru Bi
- Chongqing Academy of Agricultural Sciences, Chongqing 401329, China
| | - Yuxin Zhang
- College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China
| | - Zhangli Hu
- Guangdong Technology Research Center for Marine Algal Bioengineering, Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Longhua Innovation Institute for Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China.
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Zhang C, Chen X, Han M, Li X, Chang H, Ren N, Ho SH. Revealing the role of microalgae-bacteria niche for boosting wastewater treatment and energy reclamation in response to temperature. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 14:100230. [PMID: 36590875 PMCID: PMC9800309 DOI: 10.1016/j.ese.2022.100230] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 11/30/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
Conventional biological treatment usually cannot achieve the same high water quality as advanced treatment when conducted under varied temperatures. Here, satisfactory wastewater treatment efficiency was observed in a microalgae-bacteria consortia (MBC) over a wide temperature range because of the predominance of microalgae. Microalgae contributed more toward wastewater treatment at low temperature because of the unsatisfactory performance of the accompanying bacteria, which experienced cold stress (e.g., bacterial abundance below 3000 sequences) and executed defensive strategies (e.g., enrichment of cold-shock proteins). A low abundance of amoA-C and hao indicated that conventional nitrogen removal was replaced through the involvement of microalgae. Diverse heterotrophic bacteria for nitrogen removal were identified at medium and high temperatures, implying this microbial niche treatment contained diverse flexible consortia with temperature variation. Additionally, pathogenic bacteria were eliminated through microalgal photosynthesis. After fitting the neutral community model and calculating the ecological niche, microalgae achieved a maximum niche breadth of 5.21 and the lowest niche overlap of 0.38, while the accompanying bacterial community in the consortia were shaped through deterministic processes. Finally, the maximum energy yield of 87.4 kJ L-1 and lipid production of 1.9 g L-1 were achieved at medium temperature. Altogether, this study demonstrates that advanced treatment and energy reclamation can be achieved through microalgae-bacteria niche strategies.
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Affiliation(s)
- Chaofan Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Xi Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Meina Han
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Xue Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Haixing Chang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing, 400054, PR China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
| | - Shih-Hsin Ho
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
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Maroušek J, Maroušková A, Gavurová B, Tuček D, Strunecký O. Competitive algae biodiesel depends on advances in mass algae cultivation. BIORESOURCE TECHNOLOGY 2023; 374:128802. [PMID: 36858122 DOI: 10.1016/j.biortech.2023.128802] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
The aim of this review was to study why, despite large investments in research and development, algae biodiesel is still not price competitive with fossil fuels. Microalgal production was confirmed to be a critical cost item (84 up to 93 %) for biodiesel regardless of the production technology. Techno-economic assessment revealed the main cost drivers during mass cultivation. It is argued that a breakthrough in the cultivation efficiency of microalgae is identified as a necessary condition for achieving price-competitive microalgal biodiesel. The key bottlenecks were identified as follows: (1) light and O2 concentration management; (2) overnight respiratory loss of oil. It is concluded that most of the research on microalgae biodiesel yields economically over-optimistic presumptions because it has been based on laboratory scale experiments with a low level of interdisciplinary overlap.
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Affiliation(s)
- Josef Maroušek
- Institute of Technology and Business in České Budějovice, Faculty of Technology, Okružní 517/10, České Budějovice 370 01, Czech Republic; University of South Bohemia in České Budějovice, Faculty of Agriculture, Studentská 1668, České Budějovice 370 05, Czech Republic.
| | - Anna Maroušková
- Institute of Technology and Business in České Budějovice, Faculty of Technology, Okružní 517/10, České Budějovice 370 01, Czech Republic
| | - Beata Gavurová
- Technical University of Kosice, Faculty of Mining, Ecology, Process Control and Geotechnologies, Letna 9, Košice 042 00, Slovakia
| | - David Tuček
- Tomas Bata University in Zlín, Faculty of Management and Economics, Mostní 5139, Zlín 760 01, Czech Republic
| | - Otakar Strunecký
- Institute of Technology and Business in České Budějovice, Faculty of Technology, Okružní 517/10, České Budějovice 370 01, Czech Republic; University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Institute of Aquaculture and Protection of Waters, Na Sádkách 1780, 370 05 České Budějovice, Czech Republic
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Li C, Chen HQ, Gao P, Huang XH, Zhu YX, Xu M, Yuan Q, Gao Y, Shen XX. Distribution and drivers of antibiotic resistance genes in brackish water aquaculture sediment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 860:160475. [PMID: 36436623 DOI: 10.1016/j.scitotenv.2022.160475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/03/2022] [Accepted: 11/21/2022] [Indexed: 06/16/2023]
Abstract
Brackish water aquaculture has brought numerous economic benefits, whereas anthropogenic activities in aquaculture may cause the dissemination of antibiotic resistance genes (ARGs) in brackish water sediments. The intricate relationships between environmental factors and microbial communities as well as their role in ARGs dissemination in brackish water aquaculture remain unclear. This study applied PCR and 16S sequencing to identify the variations in ARGs, class 1 integron gene (intI1) and microbial communities in brackish water aquaculture sediment. The distribution of ARGs in brackish water aquaculture sediment was similar to that in freshwater aquaculture, and the sulfonamide resistance gene sul1 was the indicator of ARGs. Proteobacteria and Firmicutes were the dominant phyla, and Paenisporosarcina (p_ Firmicutes) was the dominant genus. The results of correlation, network and redundancy analysis indicated that the microbial community in the brackish water aquaculture sediment was function-driven. The neutral model and variation partitioning analysis were used to verify the ecological processes of the bacterial community. The normalized stochasticity ratio showed that pond bacteria community was dominated by determinacy, which was affected by aquaculture activities. The total nitrogen and organic matter influenced the abundance of ARGs, while Proteobacteria and Thiobacillus (p_Proteobacteria) were the key antibiotic-resistant hosts. Our study provides insight into the prevalence of ARGs in brackish water aquaculture sediments, and indicates that brackish water aquaculture is a reservoir of ARGs.
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Affiliation(s)
- Chao Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Hao-Qiang Chen
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Peng Gao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Xing-Hao Huang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Yun-Xiang Zhu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Ming Xu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
| | - Quan Yuan
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Yuan Gao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Xiao-Xiao Shen
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
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Sun X, Li X, Tang S, Lin K, Zhao T, Chen X. A review on algal-bacterial symbiosis system for aquaculture tail water treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 847:157620. [PMID: 35901899 DOI: 10.1016/j.scitotenv.2022.157620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 07/20/2022] [Accepted: 07/20/2022] [Indexed: 06/15/2023]
Abstract
Aquaculture is one of the fastest growing fields of global food production industry in recent years. To maintain the ecological health of aquaculture water body and the sustainable development of aquaculture industry, the treatment of aquaculture tail water (ATW) is becoming an indispensable task. This paper discussed the demand of environmentally friendly and cost-effective technologies for ATW treatment and the potential of algal-bacterial symbiosis system (ABSS) in ATW treatment. The characteristics of ABSS based technology for ATW treatment were analyzed, such as energy consumption, greenhouse gas emission, environmental adaptability and the possibility of removal or recovery of carbon, nitrogen and phosphorus as resource simultaneously. Based on the principle of ABSS, this paper introduced the key environmental factors that should be paid attention to in the establishment of ABSS, and then summarized the species of algae, bacteria and the proportion of algae and bacteria commonly used in the establishment of ABSS. Finally, the reactor technologies and the relevant research gaps in the establishment of ABSS were reviewed and discussed.
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Affiliation(s)
- Xiaoyan Sun
- School of Civil Engineering, Sun Yat-sen University, 519082 Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), 519082 Zhuhai, China.
| | - Xiaopeng Li
- School of Civil Engineering, Sun Yat-sen University, 519082 Zhuhai, China
| | - Shi Tang
- School of Civil Engineering, Sun Yat-sen University, 519082 Zhuhai, China
| | - Kairong Lin
- School of Civil Engineering, Sun Yat-sen University, 519082 Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), 519082 Zhuhai, China
| | - Tongtiegang Zhao
- School of Civil Engineering, Sun Yat-sen University, 519082 Zhuhai, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), 519082 Zhuhai, China
| | - Xiaohong Chen
- School of Civil Engineering, Sun Yat-sen University, 519082 Zhuhai, China; Center for Water Resources and Environment Research, Sun Yat-sen University, 510275 Guangzhou, China
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Ni T, Feng H, Tang J, Wang J, Yu J, Yi Y, Wu Y, Guo Y, Tang L. A novel electrocatalytic system with high reactive chlorine species utilization capacity to degrade tetracycline in marine aquaculture wastewater. CHEMOSPHERE 2022; 300:134449. [PMID: 35364089 DOI: 10.1016/j.chemosphere.2022.134449] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/25/2022] [Accepted: 03/25/2022] [Indexed: 06/14/2023]
Abstract
The problems of high salinity and coexistence of antibiotics in mariculture wastewater pose a great challenge to the traditional wastewater treatment technology. Herein, an electrocatalytic system based on cathodes to sustain reactive chlorine species (RCS) in a high chlorine environment was proposed. The results show that the content of RCS is affected by cathodes. The electrocatalytic system with FeNi/NF as cathode has the largest RCS retention capacity when compared with other cathode systems (carbon felt, nickel foam, copper foam, stainless steel, and nickel-iron foam). This is related to FeNi/NF's higher hydrogen production activity, which inhibits the reduction reaction of RCS. Furthermore, the degradation of tetracycline by the proposed FeNi/NF system maintained long-term effective performance across 20 cycles. Thus, the application of high chlorine resistance electrocatalysis system provides a possibility for practical electrocatalysis treatment of mariculture wastewater.
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Affiliation(s)
- Ting Ni
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China
| | - Haopeng Feng
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China.
| | - Jing Tang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China
| | - Jiajia Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China
| | - Jiangfang Yu
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China
| | - Yuyang Yi
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China
| | - Yangfeng Wu
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China
| | - Yuyao Guo
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China
| | - Lin Tang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, Hunan, China.
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A Study of a Composite Biofilm Reactor for the Treatment of Mariculture Wastewater: Performance and Microbial Communities. SUSTAINABILITY 2022. [DOI: 10.3390/su14105743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mariculture wastewater is one of the main sources of saline wastewater. This study used a waterfall aeration biofilm reactor combined with a sequencing batch reactor (WABR-SBR) to treat simulated mariculture sewage. Despite the high inhibition by salinity, the reactor maintained a high removal efficiency for organic matter and ammonium nitrogen. The ammonia nitrogen removal rate was greater than 99%, while that for nitrite, which is extremely toxic to farmed animals, was greater than 80%. Fourier transform infrared spectroscopy and scanning electron microscopy showed that salinity affected the surface structure and composition of biofilms, which became compact and secreted more solute to resist the impact of salinity. High throughput 16S rRNA sequencing revealed that the main phyla in the biofilms were Actinobacteria, Proteobacteria, Firmicutes, and Bacteroidetes. Metagenomic annotation of genes further indicated nitrogen metabolism pathways under high salinity. The conclusions of this study can provide a theoretical foundation for the biological treatment of high-salt wastewater and provide a technical reference for further application of the WABR-SBR composite system.
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Abstract
With the rapid development of intensive mariculture, lots of mariculture wastewaters containing residual feed and excrements are discharged into marinelands, leading to coastal pollution. Recently, the environmental problems caused by the discharge of mariculture wastewater have been paid much attention, as have other breeding industries in China. In fact, organic solid waste accounts for most of the pollutants and can be reduced by precipitation or filtration technologies, after which the supernatant can be easily treated by ecological methods. Some national guidelines and relevant local standards have been issued to strictly control the mariculture wastewater, but there are still few effective technologies for mariculture wastewater treatment due to its high salinity and extremely low pollutant concentration. This paper aims to propose feasible pollution control methods of mariculture wastewater according to the wastewater characteristics from different mariculture modes. For raw ammonia-based wastewater, it should be sequentially treated by precipitation, nitrification and denitrification and ecological methods, which would target solid waste, organic carbon/nitrogen and phosphorus removal, respectively. For the nitrate-based wastewater, this just needs denitrification filters and ecological methods for nitrate and phosphorus removal. After an overview of pollution control strategies for different types and scales of industrial mariculture wastewater treatment, some challenges are also mentioned.
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