Search Results (122)

In this study, we sought to improve the productivity of Far Eastern catfish (Silurus asotus) and tropical eel (Anguilla bicolor), which are high-value fish species in the Republic of Korea, as well as that of associated crops by applying biofloc technology (BFT)-based aquaponics systems. The following three systems were used: the flow-through system (FTS), BFT, and BFT aquaponics system (BAPs). Caipira lettuce (Lactuca sativa) was utilized and hydroponics (HP) was implemented to compare crop productivity. After 42 days of treatment, the BAPs and BFT systems improved fish productivity, with weight gain rates of 134.47 ± 1.80% in BAPs-cat, 130.38 ± 0.95% in BFT, and 114.21 ± 6.62% in FTS for S. asotus, and 70.61 ± 3.26% in BAPs-eel, 62.37 ± 7.04% in BFT, and 47.83 ± 1.09% in FTS for A. bicolor. During the experiment, the total ammonia nitrogen and NO₂⁻-N concentrations were stable in all plots. In the case of NO₃⁻-N, BFT showed an increasing tendency while both BAPs showed a decrease compared with that of the BFT. BAPs-cat (total weight: 224.1 ± 6.37 g) and HP (220.3 ± 7.17 g) resulted in similar growth. However, in BAPs-eel was 187.7 ± 3.46 g due to root degradation. Water content analysis showed that BAPs-cat and BAPs-eel contained sufficient K, Ca, P, and S, which are important for crop growth. Overall, the effect of BAPs on fish growth was higher than that of FTS. This study reveals that integrating BFT with aquaponics improves productivity for high-value fish and associated crops while maintaining stable water quality. This method offers sustainable, efficient production, reduces environmental impact, and provides insights for future research in sustainable aquaculture practices. Full article

A circular tri-trophic system integrating aquaponics, i.e., combined cultivation of crops and fish, with insect rearing is presented for lettuce cultivation. The nutrition cycle among crops, insects and fish turns waste into resource, thereby increasing the sustainability of this food production system. A comprehensive evaluation of the system’s efficiency was performed, including the growth, functional and resource use efficiency traits of lettuce, the dynamics of which were followed in a pilot-scale aquaponics greenhouse, under three treatments: conventional hydroponics (HP) as the control, coupled aquaponics (CAP) with crops irrigated with fish-derived water, and decoupled aquaponics (DCAP), where fish-derived water was amended with fertilizers to reach the HP target. The main findings indicate comparable physiological performance between DCAP and HP, despite the slightly lower yield observed in the former. The CAP treatment exhibited a significant decrease in biomass accumulation and functional impairments, which were attributed to reduced nutrient levels in lettuce leaves. The DCAP treatment exhibited a 180% increase in fertilizer use efficiency compared to the HP treatment. We conclude that the tri-trophic cropping system with the implementation of DCAP variant is an effective system that enables the combined production of crops and fish, the latter being fed with sustainably derived insect protein. The tri-trophic system improves the environmental impact and sustainability of lettuce production, while making circularity feasible. Full article

Aquaculture expansion to meet global protein demand has intensified concerns over nutrient pollution and greenhouse gas (GHG) emissions. While floating treatment wetlands (FTWs) are proven for water quality improvement, their potential to mitigate GHG emissions in marine aquaculture remains poorly understood. This study quantitatively evaluated the dual capacity of Sesuvium portulacastrum FTWs to (a) regulate dissolved inorganic nitrogen (DIN) and (b) reduce CO₂/N₂O emissions in grouper aquaculture systems. DIN speciation (NH₄⁺, NO₂⁻, NO₃⁻) and CO₂/N₂O fluxes of six controlled ponds (three FTW and three control) were monitored for 44 days. DIN in the FTW group was approximately 90 μmol/L lower than that in the control group, and the water in the plant group was more “oxidative” than that in the control group. The former groups were dominated by NO₃⁻, with lower dissolved inorganic carbon (DIC) and N₂O concentrations, whereas the latter were dominated by NH₄⁺ during the first 20 days of the experiment and by NO₂⁻ at the end of the experiment, with higher DIC and N₂O concentrations on average. Higher primary production may be the reason that the DIC concentration was lower in the plant group than in the control group, whereas efficient nitrification and uptake by plants reduced the availability of NH₄⁺ in the plant group, thereby reducing the production of N₂O. A comparison of the CO₂ and N₂O flux potentials in the plant group and control group revealed that, in the presence of FTWs, the CO₂ and N₂O emissions decreased by 14% and 36%, respectively. This showed that S. portulacastrum FTWs effectively couple DIN removal with GHG mitigation, offering a nature-based solution for sustainable aquaculture. Their low biomass requirement enhances practical scalability. Full article

Lemon basil (Ocimum × citriodorum) is a highly valued aromatic plant renowned for its distinct citrus aroma. This study aimed to evaluate sustainable substrates and cultivation systems for its production. Two complementary and sequential experiments were conducted: an initial experiment designed to compare coconut fiber mixed in varying proportions with perlite to rock wool, evaluating their effectiveness during germination and early growth (experiment 1), and a subsequent experiment aimed at assessing plant performance in a decoupled aquaponic system relative to hydroponics utilizing the best-performing coconut fiber-perlite mixture from the first phase along with rock wool as substrates (experiment 2). The substrate with 70% coconut fiber and 30% perlite (F70:P30) significantly improved seed germination, leaf number, and total leaf area of seedlings. The decoupled aquaponic cultivation system resulted in a 52.5% increase in flavonoid content, accompanied by higher calcium and magnesium uptake in stems and roots compared to hydroponics. These findings clearly underscore the potential of coconut fiber substrates mixed with perlite as sustainable alternatives to rock wool, reducing environmental impact, disposal costs, and health risks. Similarly, aquaponic cultivation emerges as a valuable strategy for sustainable lemon basil (Ocimum × citriodorum) production, offering comparable yields to hydroponics while improving plant nutritional and phytochemical quality through beneficial plant-microbe interactions. These results provide practical evidence supporting the adoption of environmentally friendly substrates and cultivation practices, thus contributing significantly toward sustainable intensive vegetable production systems. Full article

Understanding halophyte responses to agronomic management in saline environments is crucial for optimizing their cultivation. This study assessed the physiological and biochemical responses of three halophytic species, ice plant (Mesembryanthemum crystallinum L.), romeritos (Suaeda edulis Flores Olv. and Noguez), and sea asparagus (Salicornia europaea L.) cultivated in half-strength seawater aquaponics (approximately 250 mM NaCl) under the following rooting media treatments: (C) untreated rearing water (RW), (pH) pH-adjusted to 5.5 RW, (pH+S) pH-adjusted to 5.5 RW with nutrient supplementation, and (NS) standard nutrient solution + 5 mM NaCl. Salinity was the primary factor influencing plant responses, while agronomic management played a secondary role. Ice plants exhibited stable growth across treatments due to their strong succulence, high water content, and antioxidative system, requiring minimal management, though optimal pH may enhance nutrient availability. Romeritos showed high treatment variability yet maintained biomass production via Na⁺ compartmentalization, with C treatment supporting better osmotic regulation, while pH adjustments and mineral supplementation induced stress under HSW. Sea asparagus sustained growth across all treatments, likely due to effective K⁺ retention and osmoregulation, reducing the need for additional management. These findings highlight species-specific salinity tolerance mechanisms and suggest that minimal agronomic management can effectively support halophyte cultivation in saline aquaponic systems. Full article

Optimizing nutrient usage and controlling environmental parameters are crucial for improved crop growth and yield in the cultivation of Cannabis sativa, commonly known as hemp, using controlled-environment agriculture (CEA) systems. Although hemp cultivation in CEA is rapidly growing, the effects of different light-intensity treatments on early vegetative stages of hemp grown in hydroponic and aquaponic systems, along with the impacts on the environment and human health remains limited. This study employed a split-plot design, consisting of two layers of plant grow beds where each layer was exposed to different light intensities (LIs): approximately 752 µmol/m²/s (high light intensity) on the upper layer and 141 µmol/m²/s (low light intensity) on the lower layer. To assess the influence of two different LIs on plant growth indicators, specifically plant length and leaf area, the environmental parameters, including dissolved oxygen (DO), electrical conductivity (EC), pH, and water temperature (WT) were maintained within the same range for both systems. Additionally, the study incorporated a cradle-to-gate life cycle assessment (LCA) to precisely evaluate the environmental performance of both systems. Under the specific environmental and design conditions of this study, hemp plants grown in aquaponics showed greater growth performance in plant length compared to hydroponics (more than 42% higher for both LIs) and leaf area (28.3% greater under 141 µmol/m²/s), although the leaf area was 2.1% lower under 752 µmol/m²/s compared to plants grown in hydroponics. The LCA demonstrated that the aquaponic system provided an efficient and sustainable approach by integrating fish with hemp cultivation. The LCA results showed that aquaponics had a 22% reduction in midpoint and a 15% reduction in endpoint impact in contrast to the hydroponics system for hemp leaf cultivation. This research highlights the potential of aquaponic systems as a viable and sustainable alternative to hydroponic systems for hemp leaf cultivation in CEA under uncertain future climates. Full article

Rapid urbanization, climate variability, and land degradation are increasingly challenging traditional open-field farming systems. Soilless farming (SLF) has emerged as a complementary approach to enhance horticultural resilience in space-constrained and climate-stressed environments. This review critically evaluates the role of SLF within the broader framework of climate-smart agriculture (C-SA), with a particular focus on its applications in urban and peri-urban settings. Drawing on a systematic review of the existing literature, the study explores how SLF technologies contribute to efficient resource use, localized food production, and environmental sustainability. By decoupling crop cultivation from soil, SLF enables precise control over nutrient delivery and water use in enclosed environments, such as vertical farms, greenhouses, and container-based units. These systems offer notable advantages regarding water conservation, increased yield per unit area, and adaptability to non-arable or degraded land, making them particularly relevant for high-density cities, arid zones, and climate-sensitive regions. SLF systems are categorized into substrate-based (e.g., coco peat and rock wool) and water-based systems (e.g., hydroponics, aquaponics, and aeroponics), each with distinct design requirements, nutrient management strategies, and crop compatibility. Emerging technologies—including artificial intelligence, the Internet of Things, and automation—further enhance SLF system efficiency through real-time data monitoring and precision control. Despite these advancements, challenges remain. High setup costs, energy demands, and the need for technical expertise continue to limit large-scale adoption. While SLF is not a replacement for traditional agriculture, it offers a strategic supplement to bolster localized food systems and address climate-related risks in horticultural production. Urban horticulture is no longer a peripheral activity; it is becoming an integral element of sustainable urban development. SLF should be embedded within broader resilience strategies, tailored to specific socioeconomic and environmental contexts. Full article

The accurate prediction of sewage treatment indicators is crucial for optimizing management and supporting sustainable water use. This study proposes the KAN-LSTM model, a hybrid deep learning model combining Long short-term memory (LSTM) networks, Kolmogorov-Arnold Network (KAN) layers, and multi-head attention. The model effectively captures complex temporal dynamics and nonlinear relationships in sewage data, outperforming conventional methods. We applied correlation analysis with time-lag consideration to select key indicators. The KAN-LSTM model then processes them through LSTM layers for sequential dependencies, KAN layers for enhanced nonlinear modeling via learnable B-spline transformations, and multi-head attention for dynamic weighting of temporal features. This combination handles short-term patterns and long-range dependencies effectively. Experiments showed the model’s superior performance, achieving 95.13% R-squared score for FOss (final sedimentation basin outflow suspended solid, one indicator of our research predictions)and significantly improving prediction accuracy. These advancements in intelligent sewage treatment prediction modeling not only enhance water sustainability but also demonstrate the transformative potential of hybrid deep learning approaches. This methodology could be extended to optimize predictive tasks in sustainable aquaponic systems and other smart aquaculture applications. Full article

Acmella oleracea (L.) R.K. Jansen, also called jambù, is a medicinal and aromatic plant native to the Brazilian Amazon rainforest and phytochemically characterized by N-alkylamides with spilanthol as the main active compound. Jambù recently attracted the interest of many companies because of its wide range of pharmaceutical, nutraceutical, and cosmetic applications. In this context, it is desirable to identify eco-friendly cultivation methods that not only minimize the environmental footprint but also support the biosynthesis of the plant’s valuable bioactive compounds. The zero-discharge approach of aquaponics makes this growing system an eco-friendly and sustainable production strategy for crops. Thus, a greenhouse experiment was conducted on two jambù cultivars, i.e., cv ‘purple’ and cv ‘yellow’, grown in aquaponic and hydroponic systems. The objective was to compare their contents of N-alkylamides, their numbers of capitula, which are the main source of these bioactives, and their volatile profiles. The results highlighted differences between the two cultivars and among plants harvested at different periods. Interestingly, aquaponics yielded plants with a high N-alkylamide content, which was comparable to that obtained with hydroponics. Overall, this study highlighted the feasibility of adopting aquaponics to grow A. oleracea, paving the way for circular economy-based and sustainable agricultural practices. Full article

The growing global demand for fish necessitates the exploration of sustainable aquaculture practices. This has led to a focus on the quality and sustainable production of fish products with minimal environmental impact. Thus, the objective of this review is to study and evaluate how different aquaculture systems impact the quality and nutritional profile of fish. Fish are rich sources of protein, containing almost 20% protein and essential amino acids and vitamins. The nutritional value and quality of fish products are directly related to the conditions under which they are produced through aquaculture. This article considers various aquaculture systems, including closed-loop systems, pond farming, marine aquaculture, and aquaponic systems. The operating principles, advantages, and inherent limitations of each fish-rearing system are subjected to rigorous critical analysis in this review. Such practices are necessary to meet the growing demand for fish and to maintain the integrity of aquatic ecosystems for future generations. Full article

Aquaponics integrates aquaculture and hydroponics, promoting circularity through the recirculation of water and nutrients. However, waste management remains a challenge. This study aimed to evaluate the anaerobic digestion (AD) of aquaponic effluent (AE) combined with cattle manure (CM) for biogas production. An Indian model biodigester was fed with AE, CM and 1:1, 1:3, and 3:1 W (Water):CM, under anaerobic mono-digestion (MoAD) and 1:1, 1:3, and 3:1 AE:CM under anaerobic co-digestion (CoAD) conditions. The chemical characteristics of the substrates and digestates were assessed, as well as the potential for biogas production over 19 weeks. Overall, CoAD provided better results regarding the chemical characterization of the substrates aimed at biogas production. Notably, the 1:3 AE:CM ratio resulted in the most promising outcomes among the tested conditions. This ratio demonstrated higher efficiency, initiating biogas production by the third week and reaching the highest accumulated volume. It is probable that AE increased the dissolved organic load, optimizing the conversion of organic matter and eliminating the need for additional water in the process. Thus, the CoAD of AE and CM emerged as a promising alternative for waste valorization in aquaponics, contributing to renewable energy generation, agricultural sustainability, and the promotion of the circular economy. Full article

The global food production sector is under immense pressure due to rapid population growth and climate change, demanding innovative solutions for food security and sustainability. This review explores innovative advancements in agriculture and food technology, from urban farming (e.g., vertical farming, aquaponics, and hydroponics) to regenerative agriculture and agroforestry practices that enhance soil health and biodiversity. We also examine food production in extreme environments, including desert agriculture and space agriculture, as well as advances in biotechnology, synthetic biology, and nanotechnology, that enable improved crop yields and nutrition. The transformative role of AI in precision farming, predictive analytics, and water management is highlighted, as well as the importance of bioproducts and eco-friendly innovations. Finally, we discuss the vital role of policy, regulation, and community-driven approaches in shaping a resilient global food system. Through the integration of technology with sustainable practices, this review aims to inspire research into solutions that ensure future food security while preserving our planet. Full article

This paper shows a case study on a novel community-based sustainability planning framework that balances environmental, social, cultural dimensions for a high-density urban setting. The case study presents a community-driven “Four-Zero” sustainability model—zero energy, zero water, zero food, and zero waste—as a foundation for environmental sustainability practices implemented in a high-density estate in Hong Kong, alongside community-led ecological and heritage initiatives that reinforce place-based resilience. Through integrated activities, such as community farming, aquaponics, organic waste composting, biodiversity monitoring, and heritage mapping, the residents co-produced knowledge and activated novel bottom–up planning schemes and fostered social cohesion while advancing environmental objectives. Notably, the discovery of rare species and historic Dairy Farm remnants catalyzed a community-led planning proposal for an eco-heritage park that stimulated policy dialogues on conservation. These collective efforts illustrate how circular resource systems and cultural and ecological conservation can be balanced with urban development needs in compact, high-density communities. This case offers policy insights for rethinking urban sustainability planning in dense city contexts, contributing to global discourses on urban political ecology by examining socio–nature entanglements in contested urban spaces, to environmental justice by foregrounding community agency in shaping ecological futures, and to commoning practices through shared stewardship of urban resources. Full article

This systematic review explores the use of digital twins (DT) for sustainable agricultural water management. DTs simulate real-time agricultural environments, enabling precise resource allocation, predictive maintenance, and scenario planning. AI enhances DT performance through machine learning (ML) and data-driven insights, optimizing water usage. In this study, from an initial pool of 48 papers retrieved from well-known databases such as Scopus and Web of Science, etc., a rigorous eligibility criterion was applied, narrowing the focus to 11 pertinent studies. This review highlights major disciplines where DT technology is being applied: hydroponics, aquaponics, vertical farming, and irrigation. Additionally, the literature identifies two key sub-applications within these disciplines: the simulation and prediction of water quality and soil water. This review also explores the types and maturity levels of DT technology and key concepts within these applications. Based on their current implementation, DTs in agriculture can be categorized into two functional types: monitoring DTs, which emphasize real-time response and environmental control, and predictive DTs, which enable proactive irrigation management through environmental forecasting. AI techniques used within the DT framework were also identified based on their applications. These findings underscore the transformative role that DT technology can play in enhancing efficiency and sustainability in agricultural water management. Despite technological advancements, challenges remain, including data integration, scalability, and cost barriers. Further studies should be conducted to explore these issues within practical farming environments. Full article

Aquaponics, a biological production system that combines land-based aquaculture and hydroponic cultivation of plants, is a water-sharing and water-saving system that is expected to be a sustainable food production system with water and nutrient resource circulation in agricultural and fisheries fields. The balance among feeding, fish density, and plant absorption capacity was investigated to obtain fundamental data for sustainable aquaponic systems. To clarify the effects of feeding rates on biological production and nitrogen utilization efficiency, fish and plant growth performance and nitrogen flow were evaluated in an aquaponic system that combined loach aquaculture with lettuce hydroponic cultivation. Test groups with different feeding rates and different fish densities were set. As a result, the fertilizer components in loach excreta contributed to plant growth, and the growth rate of lettuce plants tended to be greater than that of control hydroponic cultivation without fish. However, there was no difference in lettuce growth at feeding rates of 0 to 2 g d⁻¹/system, but above 2 g d⁻¹/system, the growth of lettuce plants was suppressed due to an overload of excreta. The yield of loaches increased with increasing daily feeding rate per system, but a minimum feed conversion ratio was detected. The NO₂⁻ concentration increased with increasing daily feeding rate per system and amount of excreta. The nitrogen use efficiency did not change at feeding rates ranging from 0 to 1.5 g d⁻¹/system. In this feeding rate range, 80% of NUE in aquaponics was due to NUE in the plant hydroponic cultivation subsystem. However, above 2 g d⁻¹/system, nitrogen use efficiency decreased with increasing daily feeding rate per system. A feeding rate of approximately 1.5 g d⁻¹/system maximized biological production while maintaining high nitrogen utilization efficiency. In conclusion, a balance among feeding, fish density, and plant absorption capacity is essential to maintain a sustainable aquaponic system for sustainable fish and plant production as a food production system, saving water and chemical fertilizer. Full article