Fig 1 - available via license: Creative Commons Attribution 4.0 International
Content may be subject to copyright.
Schematic representation of the constructed wetland with the successive compartments (1-6, see text for details). Two aquarium air pumps provided aeration within compartments 1 and 6. Measures are in cm.
Source publication
In the Mekong delta, inland-based shrimp breeding requires significant inflow of high-quality freshwater. In turn, discharge of substantial loads of poor-quality effluents negatively impacts adjacent water bodies and favors disease outbreaks. This project describes the implementation of a laboratory-based continuous closed recirculation aquaculture...
Context in source publication
Context 1
... laboratory-based CW with horizontal subsurface flow (HSSF) was built using 8 mm thick glass plates, which were assembled manually with silicone adhesive. The CW had a total length of 125 cm, a width of 20 cm (0.25 m 2 ) and a height of 50 cm, providing a practical volume of ca. 50 L with a 20 cm water height (Fig. 1). In addition, a swirl filter (capacity ca. 8 L) was added at the inlet of the system to remove suspended solids (fecal and food ...
Similar publications
A single-stage aerobic membrane bioreactor (MBR) has been developed as an efficient and compact system for aquaculture wastewater treatment. In this study, the role of sponge media in an MBR treating synthetic aquaculture wastewater was investigated.
The MBR was operated at a hydraulic retention time of 4 h and its treatment performance during the...
Citations
... Mangrove wetlands have been studied for their ability to treat wastewater from shrimp culture (Hang Pham et al., 2021;Zhimiao et al., 2019). These wetlands were found to be effective in removing nitrite (NO 2 ), nitrate (NO 3 ), and ammonium ions (NH 4 + ) from shrimp wastewater, achieving removal efficiency of 43.6 %, 41.2 %, and 65.0 % respectively. ...
Due to the rapid growth of the aquaculture industry, large amounts of organic waste are released into nature and polluted the environment. Traditional organic waste treatment such as composting is a time-consuming process that retains the ammonia (NH 3) in the compost, and the compost produced has little economic value as organic fertilizer. Illegal direct discharge into the environment is therefore widespread. This study investigates the recovery of NH 3 through thermophilic composting of shrimp aquaculture sludge (SAS) and its application as a soil conditioner for the growth of mango plants. A maximum composting temperature of 57.10 • C was achieved through self-heating in a 200 L bench-scale reactor, resulting in NH 3 recovery of 224.04 mol/ton-ds after 14 days. The addition of calcium hydroxide and increased aeration have been shown to increase NH 3 volatilization. The recovered NH 3 up to 3 kg-N can be used as a source of clean nitrogen for high-value microalgae cultivation, with a theoretical yield of up to 34.85 kg-algae of microalgae biomass from 1 ton-ds of SAS composting. Despite the high salinity, SAS compost improved mango plant growth and disease resistance. These results highlight the potential of SAS compost as a sustainable source of clean nitrogen for microalgae cultivation and soil conditioner, contributing to a waste-free circular economy through nutrient recycling and sustainable agriculture.
... At the commencement of the experiment with full organic load, the initial DO values in both tanks planted by both Phragmites types are estimated to be approximately 5.2 ± 0.12 mg L − 1 . Following four weeks of wastewater treatment, the figure reaches about 6.0 ± 0.15 mg L − 1 in the outlet water, which is optimal for L. vannamei health (Hang Pham et al., 2021). It is evident that the DO value in all control models exhibited a significant reduction, undoubtedly owing to DO consumption by aerobic microorganisms on the wastewater surface as well as anaerobic and facultative anaerobic decomposition of organic matter in the bottom wastewater. ...
... ± 1.40. Meanwhile, during the same retention period, the S.Littoralis-planted HSSF-CW, developed by Pham et al., exhibited an ammonia removal rate of only 10% ± 5.6 on average (Hang Pham et al., 2021). The microbes thriving in the aerobic environment created by plant roots, such as ammoniaoxidizing bacteria and archaea, play a key role in driving the significant disparity through converting NH 4 + to NO 3 − . ...
The shrimp aquaculture industry, while bringing high economic benefits, simultaneously presents many environmental challenges for many countries, including Vietnam. Our survey results regarding shrimp farming management in 30 representative rural households within Ben Tre province have revealed that 96.7% of wastewater does not meet the allowable standards. Although approximately 76.66% of which is crudely treated by settling ponds, the percentage of substandard wastewater is reduced only to 70%. Unfortunately, >93% of the wastewater is discharged directly into the environment. Faced with that situation, a proposed wastewater treatment option suitable for the rural areas is to utilize settling ponds and indigenous reeds (P.australis and P. vallatoria) to build constructed wetlands (CW). A lab-scale CW was designed to mimic a settling pond on the surveyed farm, which was scaled down to a ratio of 1:500, aiming to validate the efficacy of the CW approach. Accordingly, the P.vallatoria-planted CW with a density of 25 roots/m 2 effectively treats the wastewater to meet the permissible standard within 4 weeks. The removal efficiencies of organics, nutrients, heavy metals, and total coliform could reach up to 80, 85, 91, and 41%, respectively. Upon transitioning to the field scale, these effi-ciencies increased up to 13.09, 18.79, 29.47, and 5%, respectively. More importantly, the treatment time could be shortened to 3 and 2 weeks, respectively, when the wastewater is diluted 1.5 and 3 times, thereby serving as a foundation to upgrade the current farming model from intensive to super-intensive.
... Salt-tolerant plants are able to tolerate the high salinity levels found in shrimp farming wastewater and can effectively remove pollutants through various mechanisms such as uptake, adsorption, and transformation (Lymbery et al., 2013;Szota et al., 2015). Pham et al. (2021) investigated the effectiveness of using the wetland system planted with Scirpus littoralis to treat shrimp farming wastewater. The system was operated with the high loading rate (HLR) of 1.54 m/d, the hydraulic retention time (HRT) of 1.31 h, and the salinity of 1.5%. ...
... A previous study reported that 76% of the COD of White-leg shrimp farm wastewater could be removed by using horizontal subsurface flow constructed wetlands (Pham et al., 2021). In another study, the COD removal level of shrimp farm wastewater by using horizontal subsurface flow constructed wetlands reached 92.7% (Dinh, 2017). ...
... Hybrid-constructed wetland systems have been shown to remove ammonium, TKN, and nitrate up to 83.0, 83.8, and 20.37%, respectively (Maine et al., 2022). Another study reported the removal of 78% nitrate matter in Litopenaeus vannamei farm wastewater using constructed wetlands (Pham et al., 2021). Therefore, constructed wetland models hold great promise for nitrogen treatment, especially in rural areas where land space is appropriate for modeling. ...
This study investigated a feasible model for treating actual shrimp farm wastewater at a pilot scale that could be applied to farms in the Mekong Delta area. The research was carried out using a hybrid constructed wetlands (HCWs) model, which included a floating constructed wetland (FCW, total area of 1,500 m2) and a horizontal sub-surface constructed wetland (HSCW, total area of 400 m2). The HCWs were cultivated with native plants including: Scirpus littoralis Schrab, Cyperus alternifolius, and Paspalum vaginatum. These plants are all adapted to the high salinity levels of shrimp farm wastewater. The system was operated for 30 days to treat shrimp farm effluent. Results indicated that the model effectively removed organic matter and nitrogen compounds from the wastewater. The treated wastewater had low concentrations of COD (10.0-15.4 mg/L), BOD5 (7.1-12.5 mg/L), NH4+-N (0.04-1.11 mg/L), and TN (0.17-1.83 mg/L), which met the reliable conditions for reuse or safety requirements for discharge to aquatic systems. The findings of this study have significant implications for the sustainable management of shrimp farm wastewater in the Mekong Delta area. The HCWs model is a feasible and effective way to treat this type of wastewater, and it could be adapted to other regions facing similar challenges.
... However, the differences in metal content in the plant parts between the different treatments were not statistically significant (Bhattacharya et al., 2011). As inland-based shrimp rearing necessitates a sizable intake of high-quality freshwater, Pham et al. (2021) used Scirpus littoralis to implement a continuous closed recirculation aquaculture system made up of a constructed wetland with the horizontal subsurface flow as a water treatment filter (Fig. 2). The CW was 125 cm long, 20 cm wide (0.25 m2) and 50 cm high, giving a practical volume of about 50 L at a water level of 20 cm. ...
... Treatments with ozone nanobubbles can reduce the abundance of A. hydrophila [72]. Constructed wetlands with horizontal submerged flow effectively decrease the pathogenic bacteria represented by Vibrio [73]. Improved encapsulate fishery drugs based on algal metabolites [74] and the use of probiotics, such as Phaeobacter inhibens [75], can all help to reduce the abundance of ARBs and ARGs in the water environment. ...
The accelerated development of antibiotic resistance genes (ARGs) and antimicrobial resistance (AMR) in aquaculture environments due to the overuse of antibiotics is a global concern. To systematically understand the research trends in and key concepts of ARGs and AMR in aquaculture systems, this study employed the bibliometrix R-package to conduct a bibliometric analysis of the publication characteristics of ARGs and AMR in aquaculture systems from the Web of Science, published from 2000 to 2021. The results revealed that China has produced the most papers. China and the northern hemisphere countries work closely together. Collaboration and multidisciplinary research helped to better understand the impact of AMR in aquaculture on food security and human health. Antibiotic-resistant bacteria and ARGs in aquaculture, as well as the relationship between water environmental variables, antibiotic residuals, and ARGs, are the current research focus. One of the future directions is to establish a conclusive link among water environmental variables, antibiotics, and ARGs. Another future direction is the development of new economical and environmentally friendly technologies to treat AMR in aquaculture wastewater. Collectively, our findings investigate the development directions of AMR research in global aquaculture systems and provide future perspectives.
... Gaona et al. (2016) indicated that suspended solids (250-4 000 mg/L) did not appear to affect shrimp growth, as along as high dissolved oxygen levels were provided. The methods of treating aquaculture tailwater mainly include mechanical filtration (Summerfelt and Penne, 2005), electrochemistry (Mook et al., 2012), ozone (Spiliotopoulou et al., 2018), biological action (Viegas et al., 2021), and the construction of wetland (Pham et al., 2021). Steicke et al. (2007) used polystyrene floating medium filter. ...
In recirculating aquaculture systems (RASs), the effective treatment of aquaculture tailwater is essential to maintain the health of the RAS. This study investigated the optimal time and method for tailwater treatment during three periods of the aquaculture of the Litopenaeus vannamei: nursery (0–26 d), middle (27–57 d), and later (57–104 d). The variation of several water parameters during the dissolution of total suspended solid (TSS) in tailwater, applied with the effects of ozone on the microorganism and water quality parameters were investigated. Results showed that the TSS concentrations in tailwater decreased with time, although not significantly (P>0.05), whereas total ammonia nitrogen (TAN), nitrite (NO
−2
-N), and nitrate (NO
−3
-N) increased significantly (P<0.05). Therefore, TSS should be removed from the tailwater as early as possible, being most optimal within 4 h. Ozone removed 38.24%–48.95% of TSS, 17.78%–90.14% of TAN, and 87.50%–98.90% of NO
−2
-N after 4 h of treatment. However, it resulted in the significant accumulation of NO
−3
-N. Moreover, the total number of Vibrio and bacterial counts in aquaculture tailwater was reduced completely by ozone within 4 h. Thus, these results provided technical details and data support for the effective treatment of tailwater from shrimp RAS.
... Conversely, NO 3 -N was removed more efficiently in HF-and SF-CWs (À0.03 to 0.19 g/m 2 /d) than in VF-CWs (À3.99 to À0.33 g/m 2 /d) (Figure 2), with a significant negative relationship to the DO and ORP value (Table 3). This indicates that anaerobic denitrification is proposed as the major route for removing NO 3 -N in CWs (Pham et al. 2021). ...
Black-odorous water has become a common and widespread problem in recent decades. In this study, nine constructed wetlands (CWs) with different flow types, filters, plants, and hydraulic loadings were designed according to an orthogonal array (L9 (34), and were used for the purification of black-odorous water in summer and winter. The results showed that CWs are regarded as effective to purify black-odorous water in both seasons. Microbial degradation is the major removal pathway of pollutants in CWs during summer, while the joint effect of biodegradation and adsorption is the main treatment route during winter. Flow type and hydraulic loading appear to be the most important factors impacting the purification performance of CWs, by changing the redox condition of systems and retention time of contaminants, respectively. ‘Vertical flow-zeolite filter-high loading’ is proposed as the best parameter selection for CWs on the purification of black-odorous water: among them, CWs with vertical flow have better oxygen transport capacity that is conductive to aerobic processes of pollutants, zeolite substrates may adsorb more nitrogen via ion exchange, higher hydraulic loadings can extend the contact time between contaminants and filters, and regulate the water temperature for microbial activity.
HIGHLIGHTS
CWs regarded as effective to purify black-odorous water in summer and winter.;
Flow type and hydraulic loading impact the purification performance of CWs.;
‘Vertical flow-zeolite filter-high loading’ as the parameter selection for CWs.;
... Constructed wetland (CW) is one of the most promising methods for dealing with aquaculture effluents as it possesses some advantages, such as low cost, ecological benefit and ease of operation and maintenance (Tepe, 2018;Hang Pham et al., 2021). When integrated with special matrix and aquatic plants, CW can effectively remove many types of contaminants from wastewater, including organic matter, N, P, suspended solids, heavy metals and pathogenic microorganism through the coordinated action of biological, physical and chemical processes (Almuktar et al., 2018;Wang et al., 2021). ...
... The average DO value was 5.82 ± 0.51 mg/L, 5.07 ± 0.37 mg/L, 6.38 ± 0.58 mg/L and 2.07 ± 0.29 mg/L in fish pond, sedimentation pond, aeration pond and CW outlet, respectively. The DO reduction showed an oxygen depletion in the CW, which may be related to the aerobic respiration of heterotrophic microorganisms (Hang Pham et al., 2021). During the experiment period, the integrated CW system operated stably. ...
... CW has the potential to treat P in aquaculture effluents. For example, CW as a recirculation filter in large-scale shrimp aquaculture was effective in removal of TP (65%) (Tilley et al., 2002); a laboratory-scale CW markedly removed the TP (average reduction rate 31%) from Litopenaeus vannamei farming water (Hang Pham et al., 2021). In line with previous studies, our data showed that the integrated CW system effectively removed TP with an average removal rate of 65.95% during the fish farming period. ...
In intensive inland fish farming, discharge of untreated effluents adversely affects adjacent water bodies and causes water pollution. Thus, it is highly necessary to treat the effluents from inland fish farm. In this study, we built a commercial-scale integrated constructed wetland (CW) system with vertical subsurface flow, and monitored the purifying effect. During fish farming and discharge of effluents periods, the water samples were collected to detected the total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH4 ⁺-N), nitrate nitrogen (NO3 ⁻-N), nitrite nitrogen (NO2 ⁻-N) and chemical oxygen demand (CODMn). Results showed that the system was stable and significantly improved water quality from fish pond. During the fish farming period, the removal efficiency for TN, TP, NH4 ⁺-N, NO3 ⁻-N, NO2 ⁻-N, and COD was 24.93–43.72%, 61.92–72.18%, 56.29–68.63%, 56.66–64.81%, 56.42–64.19% and 28.37–42.79%, respectively. Similarly, these parameters were also markedly decreased by the integrated CW system during sewage discharge period, and the average total removal rate for TN, TP, NH4 ⁺-N, NO3 ⁻-N, NO2 ⁻-N, and COD was 50.24%, 64.48%, 61.36%, 62.65%, 56.16% and 37.32%, respectively. It was worth noting that three key parameters for effluents detection TN, TP and COD values were below the threshold values of water quality of Class II in freshwater sewage discharge standard of China (SCT9101-2007). In conclusion, this study evidently demonstrated that application of CW system was an environmental sustainable sewage treatment strategy in intensive inland fish farming.
... The application of mechanical filters and biological filters to remove suspended particles has now become a recent technology. This novel approach has been proven to be successful in the elimination of ammonia nitrogen, nitrite, feces, uneaten feed, and at the same time improves dissolved oxygen, removes carbon dioxide and maintains optimum temperature within the culture facility thereby eliminating the possibility of disease outbreaks (Strauch et al., 2018;Hang Pham et al., 2021) inland-based shrimp breeding requires significant inflow of high-quality freshwater. In turn, discharge of substantial loads of poor-quality effluents negatively impacts adjacent water bodies and favors disease outbreaks. ...
Aquaculture production has been in existence since 12 th century, although it was unpopular due to the flourishing of capture fisheries. Up to 2000's, debates on the potentials of aquaculture as an alternative to artisanal fisheries has been intense. When Nature journal published a review on the sustainability and the contribution of aquaculture to the world from 1997 to 2017, many countries became attracted to the sub-sector, which saw its rapid development. The global aquaculture development has never been without hurdles emanating from its operations. Challenges such as proper nutritious feed, developments of antibiotics and vaccines to fight diseases and parasites, sustainable breeding techniques, social conflicts, environmental impacts, availability of good water and culture facilities as well as economic and marketing issues have kept researchers on their feet over the years in attempt to find lasting solutions. Consequently, numerous technological advancements have been recorded in recent years. Introductions of gene technology, Internet of Things (IoT), transcriptomes, nanotechnology, mechanical filters and biological filters in Recirculation Aquaculture System (RAS), Supercritical Fluid (SCF) extraction process and high-throughput messenger RNA (mRNA) sequencing (RNA-Seq) facilities have indeed broadened the prospects of eco-friendlier and more sustainable aquacultures to meet the Food and Agriculture Organization (FAO) goal of 2050.
... Omotade et al. [15] suggested that CWs (0.97 m 2 ) have a great potential for the treatment of aquaculture wastewater, which contributed to the recycling of the wastewater. A study in a laboratory-based horizontal subsurface flow CW (125 cm × 20 cm × 50 cm) showed that the nitrate, chemical oxygen demand (COD) and total aerobic bacteria were reduced substantially over 50 days and improved the water quality of the shrimp culture [16]. Meanwhile, CW microcosms (40 cm × 30 cm × 30 cm) with vertical subsurface flow can effectively remove the organic micropollutants in freshwater aquaculture effluents over 4 weeks [17]. ...
... Interestingly, the DO values were significantly higher in CW inlet than that in CW outlet, indicative of oxygen depletion in the CW. The phenomenon may be caused by the aerobic respiration of heterotrophic microorganisms in CW, which can effectively degrade the pollutants in aquaculture wastewater [16]. ...
... The CW system was also reported to be effective in the removal of TP (42%) in contaminated runoff/storm water from urban area [27]. In aquaculture effluent treatment, a study under laboratory-based CW showed an average of 31% in TP reduction [16]. In line with the previous study, our results showed that the CW system was able to effectively remove TP (39.74%) during 2013-2018. ...
In aquaculture, constructed wetland (CW) has recently attracted attention for use in effluent purification due to its low running costs, high efficiency and convenient operation,. However, less data are available regarding the long-term efficiency of farm-scale CW for cleaning effluents from inland freshwater fish farms. This study investigated the effectiveness of CW for the removal of nutrients, organic matter, phytoplankton, heavy metals and microbial contaminants in effluents from a blunt snout bream (Megalobrama amblycephala) farm during 2013–2018. In the study, we built a farm-scale vertical subsurface flow CW which connected with a fish pond, and its performance was evaluated during the later stage of fish farming. The results show that CW improved the water quality of the fish culture substantially. This system was effective in the removal of nutrients, with a removal rate of 21.43–47.19% for total phosphorus (TP), 17.66–53.54% for total nitrogen (TN), 32.85–53.36% for NH4+-N, 33.01–53.28% NH3-N, 30.32–56.01% for NO3−-N and 42.75–63.85% for NO2−-N. Meanwhile, the chlorophyll a (Chla) concentration was significantly reduced when the farming water flowed through the CW, with a 49.69–62.01% reduction during 2013–2018. However, the CW system only had a modest effect on the chemical oxygen demand (COD) in the aquaculture effluents. Furthermore, concentrations of copper (Cu) and lead (Pb) were reduced by 39.85% and 55.91%, respectively. A microbial contaminants test showed that the counts of total coliform (TC) and fecal coliform (FC) were reduced by 55.93% and 48.35%, respectively. In addition, the fish in the CW-connected pond showed better growth performance than those in the control pond. These results indicate that CW can effectively reduce the loads of nutrients, phytoplankton, metals, and microbial contaminants in effluents, and improve the water quality of fish ponds. Therefore, the application of CW in intensive fish culture systems may provide an advantageous alternative for achieving environmental sustainability.
