Aquacultural Engineering最新文献

{"title":"Innovative aquaculture cage “Flow2Vortex” ensures a sustainable biomass delivery for low trophic level aquaculture","authors":"Jamileh Javidpour ,&nbsp;Ralf Schwarz ,&nbsp;Sonia K.M. Gueroun ,&nbsp;Carlos A.P. Andrade ,&nbsp;João Canning-Clode","doi":"10.1016/j.aquaeng.2024.102390","DOIUrl":"https://doi.org/10.1016/j.aquaeng.2024.102390","url":null,"abstract":"<div><p>The increasing global demand for seafood, coupled with the limitations of current fish stocks and aquaculture practices, requires the development of sustainable aquaculture solutions. In this context, this study explores the potential of a novel cage technology - Flow2Vortex - for the cultivation of jellyfish, a low-trophic-level organism with increasing market demand. The unique cage design creates a laminar and circular water flow, providing optimal conditions for cultivating fragile planktonic species. Indoor experiments demonstrated the successful growth of jellyfish in the cage, with growth rates of up to 11.6% per day. In addition, field tests in open waters confirmed the cage's ability to maintain a diffuse and controlled flow inside, even under strong external currents. The cage also maintained significantly higher zooplankton concentrations than the surrounding environment, offering a consistent food source for the cultivated jellyfish. These findings highlight the potential of the Flow2Vortex cage for scalable indoor and outdoor cultivation of low-trophic-level organisms, such as jellyfish, contributing to the diversification and sustainability of aquaculture practices.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102390"},"PeriodicalIF":4.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860924000013/pdfft?md5=fe40c0765d931d938b51565f0d710545&pid=1-s2.0-S0144860924000013-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139108122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of an optical imaging system prototype for autonomously monitoring zooplankton in an aquaculture facility","authors":"M.N. Bowman ,&nbsp;R.A. McManamay ,&nbsp;A. Rodriguez Perez ,&nbsp;G. Hamerly ,&nbsp;W. Arnold ,&nbsp;E. Steimle ,&nbsp;K. Kramer ,&nbsp;B. Norris ,&nbsp;D. Prangnell ,&nbsp;M. Matthews","doi":"10.1016/j.aquaeng.2023.102389","DOIUrl":"https://doi.org/10.1016/j.aquaeng.2023.102389","url":null,"abstract":"<div><p>Traditional approaches to biomonitoring in aquatic systems, such as sample collection, sorting, and identification, require significant time and effort, thereby limiting the spatiotemporal resolution of sample collection. Additionally, collection and preservation of samples for subsequent taxonomic identification and enumeration leads to mortality of organisms. Recent advances in technologies that utilize optical imaging and machine learning have provided new opportunities to expedite biomonitoring and lead to significant cost savings. These technologies can be advantageous to scientists or managers that conduct routine biomonitoring to inform operations, as in the case of aquaculture facilities. The Small Aquatic Organism optical imaging system (SAO) is a high-throughput optical imaging and classification prototype system that relies on computer vision and machine learning (Support Vector Machines, or SVMs) to autonomously identify and enumerate aquatic organisms. The SAO provides a more sustainable method of collecting large volumes of data and has the benefit of being used in situ. In this study, we tested the performance of the SAO in providing comparable results to manual zooplankton community monitoring in ten ponds at an aquaculture facility. We performed a side-by-side study comparing the sampling methods of plankton tow nets, where major zooplankton taxonomic classes were manually identified and enumerated, to sampling with the SAO. Vouchered samples were used to develop a training library for the SAO, where classes consisted of water boatman and zooplankton groups: cladocerans, copepod adults, copepod nauplii, and rotifers. SAO imagery was manually classified and compared with predicted results for validation. Accuracy for the SVM classifier of the SAO was 37.4 %. Convolutional Neural Networks (CNN) and Random Forest classifiers were also applied to SAO imagery and image features for comparison. The best CNN model and our Random Forest model had accuracies of 80.4 % and 46.6 % respectively. Challenges faced included the small size of copepod nauplii and rotifers and the limited resolution of the imaging camera, although there are tradeoffs between imaging resolution and the sample processing rate. Our comparison shows that advancement in both optical imaging and ML are needed in order for the SAO prototype to yield comparable results to manual community monitoring in an aquaculture facility.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102389"},"PeriodicalIF":4.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000766/pdfft?md5=01d99910d3294b3c378aa6a0dc5324b8&pid=1-s2.0-S0144860923000766-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139100789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulation of bionic fish group movement in a land-based aquaculture tank","authors":"Yinxin Zhou ,&nbsp;Boru Xue ,&nbsp;Haibo Liu ,&nbsp;Hangfei Liu ,&nbsp;Ying Liu ,&nbsp;Zhen Ma ,&nbsp;Xiaozhong Ren ,&nbsp;Yunpeng Zhao ,&nbsp;Shupeng Du","doi":"10.1016/j.aquaeng.2023.102388","DOIUrl":"10.1016/j.aquaeng.2023.102388","url":null,"abstract":"<div><p>The previous researches on hydrodynamics in aquaculture tanks are mainly on the basis of empty tanks, but the movement of fish group has a significant impact on the hydrodynamics in the tank. In this study, a numerical model coupling the fish group and flow field in the tank was established based on computational fluid dynamics (CFD), simulating the fluctuation motion of fish group in the circular tank and square arc angle tank. The accuracy of this numerical simulation method was verified through a physical model experimental system. The hydrodynamics in two fish-free tanks (control group) and 14 cases under the influence of fish groups with different tail beat frequencies (TBF) were obtained and analyzed. The results indicate that the average velocity in the circular tank is always higher than that in the square arc angle tank, while the flow field uniformity coefficient (<em>UC</em>₅₀) of the circular tank is lower than that in the square arc angle tank except for cases of fish-free tank and tank with TBF = 3 Hz. Additionally, the circulation characteristics in the circular tank are always regular, but that in the square arc angle tank is not regular until TBF ≥ 2.5 Hz. Compared with fish-free circular tank, the presence of a school of fish in the tank significantly reduces the average velocity and <em>UC</em>₅₀ which are improved with the increase of TBF. In the square arc angle tank, the average velocity first decreases slowly and then increases rapidly, and <em>UC</em>₅₀ slowly increases and finally converges to 0.7. This study provides a numerical approach to simulate the movement of fish groups in the aquaculture tank, which can potentially promote fish kinematics research in the tank.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102388"},"PeriodicalIF":4.0,"publicationDate":"2023-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000754/pdfft?md5=1a61ea15007b7754c1dbb1bd0d506662&pid=1-s2.0-S0144860923000754-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139018997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitrogen metabolism potential in biofilm microbial communities: potential applications in the mariculture wastewater treatment","authors":"Leilei Fan ,&nbsp;Fulin Sun","doi":"10.1016/j.aquaeng.2023.102387","DOIUrl":"https://doi.org/10.1016/j.aquaeng.2023.102387","url":null,"abstract":"<div><p>Marine aquaculture wastewater is one of the major sources of nitrogen pollution in coastal areas, and excessive discharge poses a threat to human health and the marine ecosystem. In order to investigate the nitrogen metabolism potential of microorganisms in marine aquaculture water, metagenomic sequencing was conducted, and microbial communities involved in nitrogen metabolism on composite filler biofilms and their contributions to nitrogen metabolism functions were analyzed based on KEGG annotation. Metagenomic analysis revealed that nitrogen metabolism microorganisms were primarily composed of Proteobacteria, Planctomycetota, Bacteroidota, and Firmicutes. KEGG results indicated the presence of complete nitrogen metabolism pathways within the biofilm. Analysis of nitrogen metabolism modules and relative enzyme abundance showed that the nitrification module was much less abundant compared to denitrification. Denitrification, dissimilatory nitrate reduction, and ammonia conversion to amino acids were the major modules of nitrogen metabolism in the biofilm, reflecting the main nitrogen transformation pathways. The study systematically revealed key driving taxa in the nitrogen cycle within the biofilm. Proteobacteria, Planctomycetota, Bacteroidota, and Verrucomicrobia were identified as the major executors of nitrogen metabolism pathway modules and enzyme functions in the biofilm. This research underscores the diverse microbial communities cooperate to maintain the potential nitrogen removal capacity of the biofilm. This study provide new insights into the critical driving factors of nitrogen cycling in marine aquaculture wastewater, which can serve as a scientific basis for the efficient purification of aquaculture wastewater.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102387"},"PeriodicalIF":4.0,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000742/pdfft?md5=4e40e30cbca609e7c6af082b1e756bb5&pid=1-s2.0-S0144860923000742-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138656766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineral supplementation in biofloc influences growth and haemato-biochemical indices of Genetically Improved Farmed Tilapia reared in inland saline ground water","authors":"Susitharan V ,&nbsp;Sreedharan Krishnan ,&nbsp;Pankaj Kumar ,&nbsp;Kapil Sukhdhane ,&nbsp;A. Sathiya Kala ,&nbsp;A.M. Babitha Rani","doi":"10.1016/j.aquaeng.2023.102386","DOIUrl":"10.1016/j.aquaeng.2023.102386","url":null,"abstract":"<div><p>An experiment for a period of 60 days was performed with species specific mineral supplementation in biofloc system for GIFT tilapia reared in inland saline water. Four different concentrations of formulated mineral mixture (10, 15, 20, 25 g L⁻¹) were supplemented in the subculture of biofloc inoculum for different treatments (T1, T2, T3, and T4). In contrast, two control groups (conventional culture system (C) and a standard biofloc control (BC) devoid of mineral supplements) were maintained. Major water quality parameters were optimal except alkalinity and pH, which were fluctuated in the treatment groups, and higher turbidity was noticed only in the T4 group. The minerals supplemented groups had lower levels of TAN, nitrite (NO₂) and nitrate (NO₃) than conventional biofloc system (BC). Floc parameters such as floc volume, total suspended solids (TSS), total dissolved solids (TDS) and total solids (TS) were higher than the control. Haematological parameters Hb (haemoglobin) and WBC (white blood corpuscles) of fish reared in treatments were higher, ranging from (8.2 ± 0.64 −10.47 ± 0.66 g dL⁻¹) and (187.83–215.17 ± 6.58 per cumm) respectively (P &lt; 0.05) compared to both the controls. Serum parameters of fish was recorded to be higher in T2. The proximate composition analysis revealed an enhanced crude protein content (33.22 ± 1.00%, 67.68 ± 0.2%) and crude lipid (5.24 ± 0.22% &amp; 15.18 ± 0.58%) (P &gt; 0.05) content from BC, but ash content (39.11 ± 0.1% &amp; 20.35 ± 0.21%) from T4 in both dried biofloc and fish samples were higher than rest of the groups. Specific growth rate (SGR) and weight gain (WG) were recorded to be significantly higher in the T2 group. Feed conversion ratio (FCR) was observed to be better in all the treatments and the BC group than conventional control. The current investigation showed that subculture of biofloc inoculum supplemented with formulated mineral mix of 15 g L⁻¹ could be effective in terms of water quality maintenance, feed utilization, growth, survival and biochemical parameters of GIFT tilapia reared in inland saline ground water.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102386"},"PeriodicalIF":4.0,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000730/pdfft?md5=a985bbf3afd20727fc481d4d0a9dcc43&pid=1-s2.0-S0144860923000730-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138989850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sedimentation of Crassostrea gigas and Perna perna biodeposits in the South Atlantic","authors":"Eliziane Silva ,&nbsp;Carlos Henrique Araujo de Miranda Gomes ,&nbsp;Luis Hamilton Pospissil Garbossa ,&nbsp;Claudio Manoel Rodrigues de Melo ,&nbsp;Katt Regina Lapa","doi":"10.1016/j.aquaeng.2023.102385","DOIUrl":"10.1016/j.aquaeng.2023.102385","url":null,"abstract":"<div><p>This study aimed to determine the vertical sedimentation velocity of fecal and pseudofecal matter from the bivalve molluscs <em>Crassostrea gigas</em> and <em>Perna perna</em> in the Santa Catarina Island bays, focusing on two diferente locations: Caieira da Barra do Sul (CBS) and Sambaqui (SBQ). The initial phase involved collecting biodeposits using a system with twelve chambers, directing a controlled seawater flow at a rate of 500 mL.min⁻¹. The organisms were individually housed in these chambers, and biodeposits were collected over a three-hour period. Fourteen campaigns were conducted to collect biodeposits from the two species under study. Three types of samples were produced after each campaign: feces, pseudofeces, and a combination of both (F, PF, and F/PF, respectively). The subsequent phase involved evaluating sedimentation velocity in a controlled environment using a two-meter-long, 150 mm-diameter acrylic column filled with filtered seawater. Sedimentation tests were conducted using samples from the initial phase. The sample was inserted at the top of the column, and turbidity was measured over a specified period (up to 25 min). The sedimentation velocities for F were as follows: for <em>C. gigas</em>, 1.56 ± 0.19 cm.s⁻¹ and 2.08 ± 0.83 cm.s⁻¹ in CBS and SBQ, respectively, and for <em>P. perna</em>, the corresponding values were 2.36 ± 0.70 cm.s⁻¹ and 3.33 ± 0.00 cm.s⁻¹, respectively. For F/PF samples, the corresponding sedimentation velocities were: 2.41 ± 0.85 cm.s⁻¹ and 1.15 ± 0.61 cm.s⁻¹ for <em>C. gigas</em> and 2.36 ± 0.70 cm.s⁻¹ and 2.96 ± 0.64 cm.s⁻¹ for <em>P. perna</em>, in CBS and SBQ, respectively. The sedimentation rates of samples composed solely of pseudofeces could not be determined, as the particles in these samples did not settle within the 25-minute analysis period. The velocities determined were closely related to the characteristics of particles found in the marine water habitat of the organisms. Their filtration-based feeding mechanism significantly influences the vertical sedimentation velocity and biodeposit formation. The methodology used to determine sedimentation velocity proved to be effective and quick, offering a more cost-effective approach than other available methodologies.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102385"},"PeriodicalIF":4.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000729/pdfft?md5=9f2870705d2d4d70dd02dbce55ef63cd&pid=1-s2.0-S0144860923000729-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138609429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Where engineering meets biology: The Computational Fluid Dynamic analysis of a stacked duckweed bioreactor","authors":"Daniel Maguire ,&nbsp;Neil E. Coughlan ,&nbsp;Marcel A.K. Jansen ,&nbsp;Edmond P. Byrne ,&nbsp;Fatemeh Kavousi","doi":"10.1016/j.aquaeng.2023.102375","DOIUrl":"https://doi.org/10.1016/j.aquaeng.2023.102375","url":null,"abstract":"<div><p>The necessity for sustainable farming practices, wastewater valorisation and circular economy applications have prompted increased interest in duckweed cultivation. As floating plants, duckweed species show rapid growth and can be cultured agri-food industry wastewater. Further, the resulting plant biomass is a valuable high-protein livestock feed and a biofuel feedstock. The development of multitiered (i.e., vertically stacked) indoor bioreactors enable reliable, high-capacity growth irrespective of seasons. Here, a Computational Fluid Dynamic (CFD) approach was applied to a pilot-scale duckweed cultivation system to provide insight into wastewater hydrodynamics to support further development and optimisation. CFD modelling and validation indicated that the pilot-scale system behaved non-ideally, with 60.1 % of the volume considered stagnant, and with surface channelling also identified. Analysis of the aspect ratio and inlet/outlet port positions of the cultivation tray enabled a 24.3 % decrease in stagnation, as well as a significant reduction in channelling, when the number of tray inlet/outlet ports was increased from two to three. Thus, the current study highlights the value of in-depth evaluation of the fluid flow using CFD, as a strategy to improve design of duckweed cultivation systems. This strategy can be further expanded to incorporate local and temporal nutrient depletion and predict duckweed growth rates.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102375"},"PeriodicalIF":4.0,"publicationDate":"2023-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000626/pdfft?md5=fac8ada7fc1e5db8a8cc36f9410fabaf&pid=1-s2.0-S0144860923000626-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138582358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pond cascades as a tool for ecological aquaculture allowing natural zooplankton succession, nutrient retention, and multiple stocking–harvesting cycles","authors":"Lenka Kajgrová ,&nbsp;Oldřich Pecha ,&nbsp;Koushik Roy ,&nbsp;Jaromír Dvořák ,&nbsp;Marek Let ,&nbsp;Jan Potužák ,&nbsp;Jaroslav Vrba ,&nbsp;Martin Bláha","doi":"10.1016/j.aquaeng.2023.102374","DOIUrl":"https://doi.org/10.1016/j.aquaeng.2023.102374","url":null,"abstract":"<div><p>Fishpond cascades represent interconnected artificial ecosystems with multifaceted ecological and economic potential. This study investigated the fishpond cascade integrated into an agricultural landscape in South Bohemia (Czechia), employed for advanced fry production without any manuring and feeding. Four interconnected fishponds (area 1–3 ha, 1 m mean depth, batch release–refilling of water) were studied over one growing season. Results demonstrated effective nutrient recycling and removal through the cascade, showcasing its self-purification ability. Both total phosphorus and total nitrogen concentrations in the last pond of the cascade averaged at 55 % and 61 % of those in the first pond, respectively. Zooplankton communities displayed seasonal succession patterns with the dominance of microcrustaceans (mainly <em>Daphnia</em> spp.), influencing the early diets of predatory fish. The multiple stocking–multiple harvesting strategy (MSMH) was employed to maximize fish production. Albeit naturally low survival rates (3–16 %) of advanced fish fry in ponds, the ecological and economic benefits of MSMH in the pond cascade system were evident. The study indicated that pond cascade systems can be environment-friendly and economically efficient for advanced fry production, contributing to landscape sustainability, water quality, and cultural heritage. The study encourages, where appropriate local conditions allow, the establishment of pond cascade systems as an ecological engineering concept bridging aquaculture and sustainable landscape development, as well as contributing to bioremediation and other ecosystem services.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102374"},"PeriodicalIF":4.0,"publicationDate":"2023-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000614/pdfft?md5=eeabefdc04f65e046106cc11ca441edb&pid=1-s2.0-S0144860923000614-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138564537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An IoT based smart water quality assessment framework for aqua-ponds management using Dilated Spatial-temporal Convolution Neural Network (DSTCNN)","authors":"Peda Gopi Arepalli,&nbsp;K. Jairam Naik","doi":"10.1016/j.aquaeng.2023.102373","DOIUrl":"10.1016/j.aquaeng.2023.102373","url":null,"abstract":"<div><p>Assuring the quality of water is crucial for the growth and survival of fish in aquaculture ponds. Traditional methods of water quality monitoring can be inefficient which makes real-time monitoring and decision is a challenging one. Some deep learning techniques have shown apparent in improving water quality monitoring and assessment process, but encounter some limitations like data-overfitting, interpretability, and finds difficulties in capturing complex spatial and temporal dynamics that have hindered their effectiveness. To overcome these challenges, we propose an enhanced Dilated Spatial-temporal Convolution Neural Network (DSTCNN) for water quality monitoring in aquaculture, which uses an IoT system setup for capturing real-time data inputs from aqua ponds. The water quality data captured through the IoT sensors is labeled as per the water quality index (WQI) standards for analysis. This labeled data is effectively classified into two categories by the proposed DSTCNN model based on their suitability for fish growth or potential to cause fish mortality. By the leveraging power of dilated convolutions, the DSTCNN architecture accurately handles the intricacies of both spatial and temporal data, enabling it to capture essential features and patterns across multiple snapshots. This capability empowers the model to truly comprehend the complex relationships inherent in spatiotemporal data. Furthermore, to address the concerns like overfitting due to complexity of data and enhance generalization, the proposed model employs a hybrid activation function that synergistically combines ReLU and sigmoid during the activation process. The proposed DSTCNN model has been implemented on real-time and public datasets and obtained 99.28% and 99.02% accuracy respectively, whereas the state-of-the-art PCR-GB model obtains 96.97% and 97.11% accuracy on real-time and public datasets respectively.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"104 ","pages":"Article 102373"},"PeriodicalIF":4.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000602/pdfft?md5=278dd7f413082a166889d7efd69d61c5&pid=1-s2.0-S0144860923000602-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135609176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A case study comparing the addition of two different carbon sources in pilot scale RAS with trout with and without biofilters","authors":"Kim João de Jesus Gregersen,&nbsp;Lars-Flemming Pedersen","doi":"10.1016/j.aquaeng.2023.102370","DOIUrl":"https://doi.org/10.1016/j.aquaeng.2023.102370","url":null,"abstract":"<div><p>In this study, water quality and fish performance of traditional RAS with nitrifying biofilters were compared with systems operated under heterotrophic N assimilation (HET-N), a process where bacteria consume ammonium directly for growth and thereby remove dissolved N excreted from the fish, using three different modes of carbon addition. Using twelve identical pilot scale RAS, four treatment groups were established in triplicate: RAS with autotrophic biofilters (Control), RAS with autotrophic biofilters and acetate addition (BF RAS +Acetate), RAS without biofilter with acetate addition (BF RAS -Acetate) and RAS without biofilter and a biopellet reactor (Biopellet RAS). The nine RAS with carbon addition all had lower levels of nitrate and orthophosphate at the end of the trial compared to the three control RAS (approx. 70% less NO₃^- in the Biopellet RAS and 72% less PO₄^3- in BF RAS -Acetate). Without biofilters installed, both BF RAS -Acetate and Biopellet RAS maintained acceptable water quality parameters during their respective start-up phases and were fully developed in under 3 weeks. The addition of acetate to the water caused an expected formation of bioflocs in the systems, and a significant increase in bacterial activity and turbidity. Substantial feed spill was observed in RAS with acetate addition. The absence of bacterial accumulation and no increase in turbidity in the water in Biopellet RAS suggest that the processes primarily occurred within the reactor. The overall fish mortality was &lt;1%, however, both types of RAS with acetate addition led to reduced fish growth (7.4–20%) compared to the control RAS and the RAS with biopellets. Biopellets were found to reduce dissolved N and P, and had a fast start up time without deteriorating water quality, thereby showing promising traits for use in RAS.</p></div>","PeriodicalId":8120,"journal":{"name":"Aquacultural Engineering","volume":"103 ","pages":"Article 102370"},"PeriodicalIF":4.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0144860923000572/pdfft?md5=80153ebe5ebc639297c16c68696af8ff&pid=1-s2.0-S0144860923000572-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92024398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}