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Global inland aquaculture continues to grow rapidly at an annual rate of 5.8%, increasing competition for other land use thereby generating sustainability concerns. Nigeria is the largest producer of African catfish, yet species-level information is completely scanty in relation to encompassing nature of environmental, social and economic values. In this study, a field survey exercise of the operations, systems and yield of Eriwe fish farm village was conducted with 74 fish farm cooperatives. The present study sought to establish the sustainability status of catfish farming in the region using proposed indicators in the existing literature. Findings revealed catfish farming in the village is economically sustainable with an annual gross margin of$44,539 and $ 25,868, coupled with a net income of$44,386 and $ 25,728 for intensive and semi-intensive systems respectively. This was further established with net present value (NPV) of$10,279 and $ 8323 and benefit-cost ratio (BCR) of 2.16 and 2.35 for both systems respectively. Both systems were found to have low labour remuneration < 0.50, which are below the recommended standard of 1. Environmental sustainability indicators revealed 100% of farmers discharged untreated wastewater directly into the river. All catfish farmers in the village contributed to the annual upgrade of road networks and security assurance. Through this study, it was revealed catfish farming is economically sustainable in the region. However, the influence of catfish farming practices on the social factors and ecological values have been given little or no attention.

Aquaponics has the potential to produce sustainable and accessible quality food through the integration of hydroponics and aquaculture. Plants take up dissolved nutrients in fish wastewater, allowing water reuse for fish. However, the simultaneous presence of fish and plants in the same water loop has made phytosanitary treatments of diseases such as powdery mildew problematic due to risks of toxicity for fish and beneficial bacteria, limiting its commercialization. Entomopathogenic and mycoparasitic fungi have been identified as safe biological control agents for a broad range of pests. This study aimed to investigate the efficacy of entomopathogenic fungi, Lecanicillium attenuatum (LLA) , Isaria fumosorosea (IFR), and mycoparasitic fungus Trichoderma virens (TVI) against Podosphaera xanthii. Also, we investigated the possible harmful effects of the three fungal biocontrol agents in aquaponics by inoculating them in aquaponics water and monitoring their survival and growth. The findings showed that the three biocontrol agents significantly suppressed the powdery mildew at 10 7 CFU/ml concentration. Under greenhouse conditions (65-73% relative humidity (RH)), a significant disease reduction percentage of 85% was recorded in L. attenuatum -pretreated leaves. IFR-treated leaves had the least AUDPC (area under disease progress curve) of ~434.2 and disease severity of 32% under 65-73% RH. In addition, L. attenuatum spores were the most persistent on the leaves, the spores population increased to 9.54 × 10 3 CFUmm -2 from the initial 7.3 CFUmm -2 under 65-73%. In contrast, in hydroponics water, the LLA, IFR, and TVI spores significantly reduced by more than 99% after 96 hrs. Initial spore concentrations of LLA of 10 7 CFU/ml spores were reduced to 4 x 10 3 CFU after 96 hrs. Though the results from this study were intended for aquaponics systems, relevance of the results to other cultivation systems are discussed.

The Namibian hake fishery plays an essential role in both the national economy and marine biodiversity conservation. However, recent reports of declining catch volumes and profitability have raised concerns over the biological and economic sustainability of fishery. This study analyzes a 24-year dataset (2000-2024) using the Gordon-Schaefer bioeconomic model to assess sustainability, with a focus on defining Maximum Sustainable Yield (MSY), Maximum Economic Yield (MEY), and associated effort thresholds for two vessel types: wet-fish (DW) and freezer vessels (DF). In addition, using multivariate regression, we assessed the influence of environmental drivers, such as sea surface and bottom temperature anomalies, gear depth, haul duration, number of hauls, and spatial distribution. Haul duration was the only significant predictor (β = –69,179; p = 0.014), while bottom and surface temperature, mean gear depth, latitude, and number of hauls were not statistically significant ( p > 0.05). The bioeconomic model outcome reveals a long-term decline of catch and CPUE trends, with historical lows recorded in 2024. The model’s estimated overall MSY was 132,832 tonnes with an EMSY (Ecosystem-based Maximum Sustainable Yield) of 53,534 hours, while MEY and EMEY (Ecosystem-based Maximum Economic Yield) were 125,413 tonnes and 38,188 hours, respectively. However, with the actual effort levels exceeding these thresholds, the findings suggest potential overexploitation and reduced economic efficiency. About 44% of the variance in catch by DF trawlers were explained by the bottom temperature model (R² = 0.44, Adj. R² = 0.37, p  = 0.008). However, univariate relationships should be interpreted cautiously and primarily as exploratory patterns. Spatially, higher CPUE clusters were recorded between latitudes 24°S–28°S and at depths of 300–400 m. The economic assessments from 2018 and 2023 showed negative profitability when only hake revenue was considered, with breakeven prices increasing due to operational costs. However, profitability was attainable with the inclusion of ancillary revenues such as by-catch sales and quota leasing. Our study identifies the need to align fishing efforts with MEY to improve sustainability and economic returns. Long-term resilience of the hake fishery under changing climate can be achieved through stock rebuilding, adaptation to environmental variability, and implementation of cost-effective strategies.

Global climate has undergone unprecedented changes due to several natural- and human-induced factors. The present study sought to assess the impacts of climate hazards on coastal livelihoods, specifically in Ningo-Prampram district in the Greater Accra region, Ghana. The research uses participatory rural appraisal (PRA) and the analytic hierarchical process (AHP) tools to ascertain the major climatic and non-climatic events, along with their impacts. Findings revealed coastal inundation and submersion were the major stressors that triggered dysfunctions of residents’ livelihoods. Impacts from these stressors constituted decline in household income, collapse of buildings along the beach, and saltwater intrusion rendering farmlands unproductive causing reduced crop yield. Cabbage and chilli farms that are no longer arable have been sold to estate developers. Sea level rise has resulted in the submersion of coastal lands (1 km–2 km land residual inland). Residents undertake temporal evacuations with financial assistance from local financial institutions. Minor interventions like the growing of mangroves and coconut trees have been initiated to somewhat serve as defence mechanisms. However, residents have continuously harvested these plants along the coast with no plans for afforestation, re-afforestation and other sea defence mechanisms. This leaves the area highly vulnerable, hence, the present study attempted to bridge this paucity of knowledge to inform the decision of relevant stakeholders in prioritizing climate-related issues that affect livelihoods in the area.

Aquaponics is a food production system that combines aquaculture with hydroponics. The simultaneous existence of fish, beneficial bacteria and plants in the same water loop predisposes the fish and bacteria to a possible detrimental effect of plant protection products. Additionally, there is an inadequate exploration of scientific studies on the impact of pesticides on fish and bacteria in aquaponics systems. This study investigated the effects of three commercial insecticides based on the following active ingredients: pyrethrum, azadirachtin, and spinosad, on aquaponics systems. Due to ethical concerns in animal testing, applying insecticides directly to aquaponics setup was impossible. Therefore, three separate experiments were conducted: (1) Pesticide runoff rate – in which insecticides were applied to basil ( Ocimum basilicum ) plants grown in two hydroponic systems: media bed and floating raft. The concentrations of applied insecticides were measured in the water of nutrient solutions of the hydroponics after 1, 3, 6, 12, 24, 36, 48, 72 and 96h to establish a pattern of degradation of insecticides. The result from this experiment showed that pyrethrum and spinosad were detected in unquantifiable concentrations in the nutrient solutions. Hence, further experiments were conducted only with azadirachtin. In a biofilter trial (2) – azadirachtin, at three concentrations (1.5 µg L -1 ; 7.5 µg L -1 ; and 15 µg L -1 ), was added to a running biofilter to investigate the effects on nitrifying bacteria. Mild effects were recorded in the nitrification and bacteria microbiome. In the third trial (3) – Nile tilapia ( Oreochromis niloticus ) were exposed to similar concentrations of azadirachtin for seven days (and the same period for recovery) to investigate effects on fish hematology, blood biochemistry, antioxidative enzymes in the brain, gills, muscle, liver and intestine and histopathology of gills and liver. Results showed mild effects in hematology and biochemistry profile in fish and higher levels of lipid peroxidation in the liver during the exposure. The results indicate a safe use of pyrethrum and spinosad in aquaponics setup, while azadirachtin has to be used with care, especially in coupled aquaponics systems.

Addressing undesirable changes associated with the driving forces of land use cover change are critical to sustainable land management, and the future modeling of land use systems in developing countries. The study accentuates local drivers of land use cover change in Southwestern Ghana using a mixed-method approach. The approach aided in identifying key land-use drivers, using different research strategies for comparisons through confidence level analysis and Analytic Hierarchy Process. We used expert interviews, existing literature and geostatistical tools to ascertain the driving forces triggering such unprecedented changes. Landsat imagery 5 MSS, 4 and 5 TM, 7 ETM + and 8 OLI/TIRS were acquired from the United States Geological Survey’s website. Land-use analysis revealed a decline in forests (− 82.41%) and areas covered by waterbodies (− 27.39%). A fundamental drift in built-up (+ 1288.36%) and farmlands/shrubs (+ 369.81%) areas were also observed. The contribution rate of change analysis revealed built-environment and increasing population contributed the most to surface temperature and land-use change. A steady increase in surface temperature can be attributed to the undesirable changes associated with land-use systems over the past 50 years. Socio-economic development in Southwestern Ghana is fuelling interest in studies related to land use cover change. Biophysical, cultural and technological factors are considered key drivers despite the “medium-to-very low confidence” in results generated. They could potentially impact climate-sensitive sectors that significantly modify land-use systems from the pessimists’ and optimists’ perspectives. Standpoints established through this study will enrich basic datasets for further studies at the continental level.