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Soil erosion has long been a significant environmental challenge in Ethiopia, prompting large-scale soil and water conservation (SWC) and land-restoration interventions since the 1980s. However, empirical evidence on their effects on erosion reduction across farming systems has remained limited. This study evaluates the impacts of land restoration interventions on soil erosion and sediment export across four farming-system zones by integrating 23 years of restoration investment data, remote sensing data and field measurements using Google Earth Engine and the InVEST-SDR model. The model output for sediment yield was validated by comparing model-predicted sediment yields with observed sediment yields from 16 monitoring stations distributed across 4 major river basins, corresponding to the 4 farming systems. These are Tekeze representing the Low Potential Cereal (LPC), Abay (the Nile) representing the High Potential Cereal (HPC), the Omo-basin representing the High Potential Perennial (HPP) and the Shebell basin representing the Khat-Sorghum and potato (KSP) sin the Hararghe plateau. The type and extent of restoration data were obtained from the Ministry of Agriculture database. Nearly 28 million hectares of degraded land have been rehabilitated through physical and biological SWC measures in the highlands of Ethiopia. Land-use/land-cover analysis reveals a substantial doubling of forest area. At the same time, bare land declines nearly threefold, reflecting the regreening effect of sustained restoration. Mean soil erosion declined from 55 t/ha in 2002-2009 to 24 t /ha in 2016-2025, while sediment yield decreased from 2.49 t/ha to 1.32 t/ha, representing more than a 50% reduction. The model validation demonstrates low prediction bias (PBIAS = -1.85%) and a high coefficient of determination (R2 = 82.70%), suggesting that the model is a good predictor of observed sediment yield. However, highly significant variation in soil erosion and sediment yield rates was observed across farming systems (p < 0.001), with the LPC and HPC systems remaining the most degraded. Although significant progress has been achieved in restoring degraded lands in the Ethiopian highlands, the highland cereal systems (LPC and HPC) continue to experience the highest erosion rates. This underscores the urgent need to shift from predominantly physical structures to integrated conservation practices. Most effective conservation activities will definitely be an essential ingredient toward ensuring the success of any future restoration activities.
Atlantic salmon (Salmo salar) populations continue to experience significant declines across the North Atlantic due to a myriad of factors including acidification, invasive species, and warming waters related to climate change. Temperature is a key habitat metric for salmonids but the underlying factors that drive riverine thermal regimes, and the fine-scale thermal suitability of ecologically significant salmon watersheds in the province of Nova Scotia, Canada, remains largely unknown. Here, we combined field data with a machine learning approach to: (i) identify the main environmental factors driving riverine thermal variability in two large watersheds in the Nova Scotia Southern Uplands region; and (ii) examine thermal habitat suitability for Atlantic salmon in the ∼2313 km of river network that comprise the studied watersheds. We found that riparian forest cover, landscape forest cover, and elevation had a significant cooling influence on water temperature, whereas slope, wetlands and developed areas had a warming effect. Our predictions and thermal suitability maps suggest that 55% (∼ 666 km) of the LaHave River (1214 km) and 22% (∼235 km) of the St. Mary's River (1072 km) are predicted to have stressful average temperatures for adults during the summer. Daily maximum temperature exceeded 20 °C for more than 40% of the study period in 89% (∼ 1084 km) of LaHave River, and 84% (∼ 903 km) of St. Mary's River. Daily maximum temperature exceeded 23 °C over 40% of the study period in 26% (∼ 318 km) of LaHave River, and 10% (∼ 110 km) of St. Mary's River. Significant reaches of both river networks are approaching stressful conditions for adult Atlantic salmon in the warmer months, while thermal conditions are more tolerable to juveniles. Such scenarios underscore the importance of protecting high-quality habitats and thermal refugia, without which salmon populations in this region are unlikely to recover.
Quantifying the magnitude and spatial variability of soil erosion and identifying its dominant controls are essential for understanding erosion processes and designing suitable conservation strategies, particularly in fragile mountain ecosystems. Despite extensive research, the relative importance of controlling factors remains insufficiently resolved in complex Himalayan terrains. In this study, soil erosion rates across major land-use systems in the Himalayas were quantified using the fallout radionuclide 137Cs technique and integrated with RUSLE modelling to assess present and future dynamics. The mean soil erosion rate was estimated at 21.4 t ha-1 yr-1 (137Cs) and 27.1 t ha-1 yr-1 (RUSLE), exhibiting a clear gradient across land uses (forest < grassland < scrubland < agriculture < barren land). Model validation showed close agreement between observed sediment yield in the Tehri Dam Reservoir (Bhagirathi River) catchment (10.23-13.05 t ha-1 yr-1) and the RUSLE-derived sediment yield estimate (11.91 t ha-1 yr-1), supporting the reliability of the erosion predictions. Topographic attributes, especially support practice factor (P factor) and slope, emerged as the primary determinants of spatial erosion patterns, highlighting the dominant role of terrain in regulating soil redistribution. Climatic drivers, predominantly rainfall erosivity, were identified as the most dynamic factors influencing temporal variability and future trends. Soil organic carbon, vegetation cover, and anthropogenic disturbances further modulated erosion responses. Climate projections based on IPCC SSP scenarios indicate a consistent increase in soil erosion under moderate- to high-emission pathways (SSP2-4.5 and SSP5-8.5), driven by intensified precipitation regimes, whereas a comparatively low increase is projected under the low-emission scenario (SSP1-2.6). Under the high-emission SSP5-8.5 scenario, future precipitation is projected to increase by an average of 27.3%, resulting in a corresponding mean increase of up to 37.1% in soil erosion rates. Among land-use systems, forests demonstrated greater resilience to future erosion, while barren lands remained highly vulnerable. The findings establish that while topography governs the baseline spatial distribution of soil erosion in the Himalayas, climate change acts as a critical amplifier of future risks. The findings underscore the need for climate-adaptive erosion control strategies tailored to topographically sensitive areas to mitigate future soil degradation risks and promote sustainable soil and water conservation. Our study serves as a valuable reference for future research on the long-term evolution of soil erosion in subtropical hilly and mountainous regions, especially in the context of climate change.
The evolving coastal flood hazards in the Arctic remain poorly categorized due to sparse observations, leaving it unclear when and where storm-driven water levels are intensifying or what physical processes drive them. Here we use a 45-year hydrodynamic hindcast of storm-driven water levels across Northern and Western Alaska (Bering, Chukchi, and Beaufort Sea coastlines), validated against coastal water level observations with a mean uncertainty of 0.2 m, to quantify the shifts in extreme event frequency and magnitude, identifying turning points in long-term surge trends, and attribute them to evolving atmospheric and cryospheric drivers. Model validation against statistically significant turning points occur across all major seas, with return levels of the storm driven water levels increasing by up to 30% in the Bering Sea and 10-20% in the Chukchi and Beaufort Seas. Seasonal analyses reveal intensification during late fall and winter, extending the hazard window into early winter months. Attribution analysis of the environmental drivers revealed that before the turning point, sea ice exerted the greatest influence on water levels (∼60%), with 10 m wind and sea level pressure playing smaller roles. After the turning point, the influence of sea ice declined (<50%), while wind and pressure together increased in importance (from ∼25% to ∼45%). Our results show that the compounding effects of the changing environment in the Arctic exacerbate storm-driven water levels.
The presence of organic micropollutants in highly modified lowland rivers is a growing concern for the environment and human health. This study employs both target and non-target analysis over two years with high spatiotemporal resolution in the Münstersche Aa River which is influenced by both agricultural and urban land use to identify major stressors, their input pathways and the impact of low-flow conditions. Treated wastewater is the major input pathway for pharmaceuticals, illicit drugs as well as for pesticides and biocides. Moreover, urban and agricultural non-point sources contribute to the input of organic micropollutants. Database search identified sartans as a therapeutic class of pharmaceuticals of interest in the river and spatiotemporal analysis for two years showed wastewater treatment plants as the major input source with highest concentrations of >1 μg/L in summer at low-flow conditions for the sartans. Thereby, mean concentrations of candesartan and valsartanic acid as well as the carbamazepine metabolite 10,11-dihydro-10,11-dihydroxycarbamazepine exceeded health orientation values. For the first time, the UV protection agent 2-[4-(Diethylamino)-2-hydroxybenzoyl] benzoic acid (DHHB) was tentatively identified in a river. Fold change analysis at Lake Aasee, which is a small, shallow reservoir lake in the Münstersche Aa River system, stagnant at low and flowing at high discharge, revealed that elimination and associated formation processes are responsible for the changing occurrence of features at the inflow and outflow of the lake. The exact mechanisms need to be further evaluated. The present study provides valuable insights to stressors in high modified water bodies and shows that fold change analysis after non-target data processing is a valuable tool to gain insights into transformation processes in lakes and rivers which can aid in prioritizing research in the future.
The residues of the herbicides applied to a primary crop may be phytotoxic to subsequent harvests, requiring a study of their dissipation and persistence in soils under different environmental management. Research on the dissipation and persistence of the herbicide aminopyralid has been limited to conventional soil management practices in field settings, with no studies conducted under alternative agronomic management methods. Therefore, the objective of this study was to investigate the effect of different agronomic management practices (soil type, application of green compost (GC) as organic amendment, herbicide dose, and irrigation regime) on the dissipation and persistence of the herbicide aminopyralid applied to a winter wheat crop under greenhouse conditions. Two soils with different characteristics (SA and SB) were amended with GC at 2.5% (w/w) (SA + GC and SB + GC). Wheat was sown in pots with unamended and amended soils. Each soil with one control (Control, without herbicide) and two herbicide doses (D1, agronomic dose, and D2, double agronomic dose) received two irrigation regimes (AR, average rainfall, and MR, minimum rainfall). The dissipation curves were obtained and the data were fitted to different kinetic models to calculate half-life values (DT50, days). The dissipation rate of aminopyralid was higher in SB (DT50 = 7.7 days) than in SA (DT50 = 8.6 days) under AR, falling within the range of values determined for its dissipation in the field. The dissipation rate in amended soils (SA + GC and SB + GC) increased compared to unamended soils, and the DT50 values decreased from 1.7 to 3.3 times. The DT50 values in SA and SB + GC increased from 1.2 to 1.6 times when D2 was applied. In general, soils under AR had a higher aminopyralid dissipation rate and lower DT50 values than soils under MR, in which the herbicide was more persistent at 90 days. Our results show that the agronomic practices also impact upon wheat development, being negatively affected by acidic soil (SA), the higher herbicide dose (D2), and water stress (MR) under greenhouse conditions. Overall, herbicide persistence was higher in soils under minimum irrigation, which should be considered in order to estimate the fallow period for reducing herbicide carryover and protecting rotational crops under future climate scenarios.
Mangroves are among the most carbon-rich tropical ecosystems; however, the long-term dynamics of their carbon storage in Thailand remain poorly understood. This study integrates palaeoecological records, sedimentological variables, and soil carbon to evaluate the drivers that influence millennial-scale carbon accumulation in two estuarine mangrove ecosystems from two case study sites (Bang Khun Thian and Klong Kone) in the upper Gulf of Thailand. Across the study sites, total soil carbon (Soil C) storage, determined from accumulating the organic carbon density throughout each sediment profile, ranged from approximately 3300 to 3970 Mg C ha-1. The carbon accumulation rates (CAR) varied substantially, ranging from 185 to 1256 g C m-2 yr-1 over the last millennium. The results showed that long-term soil carbon storage was not controlled by a single factor but by interactions among dry bulk density, CAR, sediment texture, mangrove occurrence, and past environmental conditions. Soil C was more closely linked to mangrove presence and fine-grained sediment retention, whereas CAR was more sensitive to hydrological connectivity. Palaeoecological records indicate that estuarine geomorphology was strongly influenced by sea-level change, sediment inputs from both allochthonous and autochthonous sources, and mangrove vegetation cover. During periods of rising sea levels and wet climatic conditions, mangrove expansion promoted high sediment accretion and carbon burial, whereas periods of marine regression led to mangrove retreat. Reduced tidal influence and land-use changes have lowered carbon input and storage. These patterns reflect the combined influences of sediment supply, hydrological connectivity, and vegetation change. Gathering data from deeper soil layers and conducting site-specific factor analyses are crucial for a more precise and comprehensive evaluation of coastal carbon storage. Therefore, long-term data are critical for designing climate adaptation policies that safeguard mangrove persistence and maximise the role of blue carbon in climate change mitigation.
Pharmaceutical contamination in aquatic ecosystems is a growing concern for marine biodiversity and human health. We have detected six different non-steroideal anti-inflamatory drugs (carprofen, ibuprofen, ketoprofen, phenylbutazone, diclofenac and flunixin), five antibiotics (florfenicol, enrofloxacin, ciprofloxacin, oxytetracycline and trimethoprim), acetaminophen and caffeine in liver samples from 13 bottlenose dolphins (Tursiops truncattus) and 14 striped dolphins (Stenella coeruleoalba) inhabiting the western Mediterranean Sea and stranded in the coast of Valencian Community (Spain) between 2010 and 2024. To our knowledge, this study is the first documentation of some of these pharmaceuticals in wild marine-mammal tissues. Our results confirm the presence of these contaminants in the Mediterranean marine ecosystem and their incorporation into the top predator level, likely mainly through the food chain. These pollutants could cause physiological alterations in exposed individuals and may represent a potential risk for population health and resilience under chronic exposure scenarios. Potential sources of such contamination include domestic wastewater and discharges from large cruise ships, as well as open aquaculture plants, highlighting the need for enhanced monitoring and awareness to mitigate the impact of pharmaceutical contamination in marine mammals and advocate for effectively protecting marine biodiversity and human health.
The fumigant pesticide 1,2-dibromo-3-chloropropane (DBCP) was widely used in California agriculture during the 1960s and 1970s before being banned in 1979. Despite this ban, DBCP continues to contaminate groundwater due to its persistence and mobility. This study evaluates the distribution, historical trends, and projected persistence of DBCP in California using data from over 13,000 public supply wells and additional domestic, irrigation, and observation wells (1980-2022). Since 2010, DBCP has been detected in 9% of public-supply wells statewide, with higher frequencies in the San Joaquin Valley (21%) and upper Santa Ana River watershed (13%), where DBCP use was most prevalent. Approximately 70% of wells had decreasing concentration trends, whereas increases were more common in deeper wells, indicating downward vertical migration of the DBCP front. Groundwater-age estimates show that recharge timing aligns with the 1960s-1970s loading period, enabling reconstruction of peak inputs and providing a basis for age-based modeling. To estimate future persistence, we applied a one-dimensional advection-dispersion model that simulates long-term declines in peak concentrations based on groundwater age, historical loading, and a 38-year degradation half-life. Model projections suggest that concentrations above the maximum contaminant level may persist in a declining number of wells until approximately 2080 (range: 2048-2109), with longer persistence in the San Joaquin Valley. The simplified modeling framework, based on age distributions typical of wells capturing peak concentrations, can provide practical regional-scale assessment of non-point source contaminants where long-term monitoring exists. This study highlights how the legacy of DBCP contamination will likely affect California's groundwater resources throughout the 21st century.
This study investigates the sources, distribution, and ecological and human health risks of metal(loid)s in sediments from the lower 8.3 miles of the Lower Passaic River (LPR), a Superfund site within the New York-New Jersey Harbor. Analysis of sediment samples revealed elevated concentrations of As, Cd, Cr, Cu, Mn, Pb and Zn, indicating localized enrichment across reaches. Ecological risk indices (i.e., CF, Igeo, EF, PERI, and PLI) classified sediments as severely contaminated, particularly with Cd and Pb, with a mean potential ecological risk index (PERI) value of 801, far above the threshold for serious risk. Sediment quality guideline indices suggested moderate to high toxicity potential. Probabilistic health risk assessment of sediment-associated metal(loid)s showed that ingestion was the dominant exposure pathway, followed by dermal contact, while inhalation contributed minimally. Pb was the main contributor to non-carcinogenic risk, with the total hazard index (HI = 1.22) exceeding the acceptable threshold, whereas other metal(loid)s showed negligible individual risks. Carcinogenic risk was primarily driven by Ni and Cr, with a cumulative deterministic total lifetime cancer risk (TLCR) of 3.38 × 10-4, indicating moderate concern, although these estimates are conservative given the presence of unmeasured carcinogenic species of Ni/Cr/As. In contrast, probabilistic Monte Carlo estimates yielded mean lifetime cancer risk (LTCR) values within the acceptable range (1 × 10-6-1 × 10-4). Monte Carlo simulation and sensitivity analysis identified sediment concentration (C), exposure frequency (ExF), exposure duration (ED), and ingestion rate (IngR) as key factors influencing risk variability, while body weight (BW) and average time (AT) reduced risk estimates. Principal component analysis (PCA) revealed mixed geogenic and anthropogenic controls, including natural background (PC1, 71%), industrial/legacy inputs (PC2, 11%), and urban-related enrichment (PC3, 8%). These findings emphasize the necessity of continued remediation efforts, including sediment dredging, to protect ecosystem health.
Contaminants of Emerging Concern (CECs) pose a serious threat to global environmental and human health. Among the most concerning are per- and polyfluoroalkyl substances (PFAS) and pharmaceuticals, which have been detected at alarming concentrations in waterways and wildlife, including fish. However, there is limited information on the concentrations of many of these pollutants in UK marine fish. Although, fish consumption from UK waters is a potential source of exposure to a range of POPs, there have been few assessments of exposure and risks from UK fisheries. In this paper, we quantified the concentrations of several PFAS and APIs in demersal fish tissue from four UK sites associated with industrialised cities (Mersey and Humber estuaries) and non-industrialised regions (North West Scotland and Cornwall) using quantitative liquid chromatography-mass spectrometry (LC-MS). PFAS concentrations were exceptionally high relative to EPA risk-based thresholds. For instance, perfluorodecanoic acid (PFDA) was detected in every sample (41/41), with an average of 3.27 (± 0.15 SE) ng/g wet weight in industrialised areas. Concentrations of pharmaceuticals varied across our targeted panel; diclofenac was detected in every fish at an average of 7.07 (± 0.85 SE) ng/g wet weight and the antidepressant Venlafaxine was detected in 13 of 41 fish at an average concentration of 3.40 (± 2.0 SE) ng/g wet weight in industrialised areas. Concentrations of several of the PFAS were concerningly high. For example, the PFDA level of exposure if these fish were consumed would exceed the US Environmental Protection Agency recommended limit by up to ~500-fold. This study provides crucial evidence for the bioaccumulation of PFAS and APIs in the marine food chain, which have the potential to affect animal, human and ecosystem health.
Mining and the metalliferous industry create solid waste byproducts hazardous to the environment. The current study characterized the hazardous nature of 2 complex, real-world slag materials according to: (i) US EPA Identification of Listing of Hazardous Waste (40 CFR 261.24) and Land Disposal Restrictions (40 CFR 268.48) according to TCLP regulations; (ii) Québec's Soil Protection and Rehabilitation of Contaminated Sites Policy (SPRCSP), Québec's Regulation Respecting Hazardous Materials (Q-2, r. 32), and Québec's surface water quality criteria (SWQC). Microbial induced carbonate precipitation (MICP) was used as a solidification/stabilization (S/S) technique for the hazardous, leachable materials. S1 exhibited biologically induced calcium carbonate (CaCO3) precipitation at the surface of slag particles but insufficient precipitation occurred to bind the particles for development of a biocement matrix. In contrast, S2 developed a biocement matrix that withstood slaking and water absorption. The Sporosarcina pasteurii treated samples precipitated CaCO3, dolomite (CaMg(CO3)2), and magnesite (MgCO3). Uniquely, CaCO3 precipitated uniformly around the slag particles causing particle-particle binding, but MgCO3 precipitated at the surface creating a crust. Formation of a densely compacted biocement matrix occurred that resisted physical degradation over 168 h. Eleven metal(loid)s exhibited a reduction in leaching in the bacteria treated sample in contrast to an untreated sample. The results suggest MICP efficacy is case specific influenced by initial magnesium concentration, pH, and pore structure, whereby higher values are suggested to have improved carbonate precipitation and biocementation. The results from this study successfully illustrate the unique mechanisms of S/S via MICP to better understand the field of biochemical remediation to complex, real-world slag materials.
Matagorda Bay, a shallow, microtidal estuarine system, located along the northwestern Gulf of Mexico/Texas coast, faces considerable challenges due to natural events and anthropogenic activities, leading to the resuspension and dispersal of sediment and pollutants within the water column. Here, we reconstructed historical trends and the spatial distribution of total mercury (T-Hg) concentrations in surface and subsurface sediment across the bay using 49 vibra-cores collected between 2021 and 2023. Bulk and clay-normalized T-Hg concentrations revealed a localized contamination hotspot near the ALCOA-Point Comfort chloralkali facility in Lavaca Bay with peak concentrations reaching 983.7 ng g-1. T-Hg concentrations decreased with increasing distance from Cox Bay, identifying the chloralkali facility as the dominant point source, though additional inputs from wastewater discharge and agricultural runoff contribute to Hg enrichment in other parts of the bay. Downcore trends suggest that industrial point sources are the dominant contributor to T-Hg loading in the region, with limited influence from fluvial sources. Despite a fast recovery time and recent cleanup efforts, portions of the bay continue to contain significant T-Hg concentrations. While recent declines in T-Hg concentrations and fish tissue levels suggest gradual recovery, continued navigational dredging activities, shrimp trawling, oyster dredging and storm-driven sediment resuspension threaten to remobilize legacy contaminants. These findings underscore the need for regionally informed management strategies to mitigate the ecological and public health risks associated with sediment-bound Hg.
The Venice Lagoon has experienced a long-term decline of salt marsh habitats due to sediment deficit, morphological deepening, increased hydrodynamic exposure, and human-induced alterations to lagoon processes. Identifying suitable locations for restoration is therefore a key challenge for lagoon management. This study applies a participatory GIS-based Multi-Criteria Decision Analysis (S-PMCA) to support the spatial prioritization of salt marsh restoration and rebuilding within the framework of the WaterLANDS and REST-COAST projects. The analysis combined stakeholder knowledge with spatially explicit environmental information. An initial set of criteria was reviewed through a pre-workshop survey involving 21 stakeholders and subsequently refined during a workshop attended by 43 participants. The final analysis incorporated six spatial criteria: distance from canals, wind fetch, proximity to existing salt marshes, historical salt marsh loss, seagrass protection, and water quality. Criteria were transformed into standardized suitability layers and weighted according to stakeholder preferences. Distance from canals received the highest average importance weight (21.4/100), whereas water quality received the lowest (13.8/100). Suitability maps were generated using an Ordered Weighted Averaging (OWA) approach and combined with a bathymetry-based proxy of restoration costs to perform a spatial cost-effectiveness assessment. Priority restoration areas were identified along lagoon margins and near the Malamocco-Marghera Canal, where wave attenuation potential, ecological connectivity, historical marsh presence, and favourable implementation conditions converge. By combining stakeholder preferences with morphodynamic conditions, ecological factors, and implementation costs, this study supports the identification of restoration areas that are both feasible and strategically relevant in the Venice Lagoon.
Nitrogen (N) is an essential macronutrient required to enhance plant growth and yield. However, 50-70% of applied N is lost in cropping systems. N stabilizers can reduce these losses by modulating microbial N transformation processes, yet their effectiveness in boreal podzolic soils remains understudied. A field experiment was conducted to evaluate the effects of N stabilizers and short-term crop rotation on soil mineral N and the relative abundance of key genes involved in nitrification and denitrification processes, 15 days after N application. Treatments included five N sources (control (CT), urea (UR), and three stabilizers: a urease inhibitor [N-(n-butyl)-thiophosphoric triamide (NBPT)], a nitrification inhibitor [nitrapyrin], and a dual inhibitor [NBPT + dicyandiamide]) and three crop rotations (corn-corn (c-c), corn-wheat (c-w), corn-faba bean (c-fb)). N stabilizers differentially affected soil mineral N relative to urea: the urease inhibitor (Agrotain (AG), urea coated with N-(n-Butyl) thiophosphoric triamide [NBPT]) increased NH₄+ availability, consistent with reduced NH₃ loss, whereas the nitrification inhibitor (eNtrench (EN), urea coated with nitrapyrin) delayed the nitrification process and the dual inhibitor (SuperU (SU), urea coated with dicyandiamide and NBPT) increased NH₄+ availability and delayed the nitrification process, again consistent with reduced NH₃ loss. Importantly, all N stabilizers significantly suppressed the relative abundance of nitrification and denitrification genes relative to urea. Among crop rotations, c-fb rotation (which received the lowest N rate) reduced NH4+ and NO3- concentration and the relative abundance of amoA AOB, amoA AOA, nxr-nitrospira, and nirK genes compared to c-c rotation. The nosZ gene abundance was highest in urea-amended c-w rotation and lowest in control treatment across all rotations. We conclude that N stabilizers and c-fb rotation effectively suppress the relative abundance of nitrification and denitrification genes in boreal podzolic soils; lower gene abundances under c-fb rotation were associated with the lower N input, though rotation and N rate effects could not be separated.
Bangladesh's fisheries sector, central to national nutrition, food security, and rural livelihoods, is increasingly threatened by the convergence of zoonotic pathogens, antimicrobial resistance (AMR), and environmental degradation. Using a One Health framework, this review synthesizes evidence from 87 peer-reviewed articles, institutional reports, and regional studies to demonstrate how interactions among aquatic ecosystems, farmed and wild fish populations, and human communities drive the emergence and transmission of disease. Zoonotic parasites including trematodes, cestodes, nematodes, and protozoa persist through contaminated water, inadequate market hygiene, and exposure to domestic and wild animals. Aquaculture systems are further burdened by zoonotic bacteria (e.g., Vibrio spp., Aeromonas spp., and Mycobacterium spp.) and microsporidian parasites (e.g., Enterocytozoon spp.), together posing significant occupational and foodborne risks. Emerging fungal pathogens, notably Saprolegnia spp. and Aphanomyces invadans, intensify disease burdens under poor farm management and environmentally stressed conditions. Critical contamination pathways, industrial and agricultural runoff, cross-contamination in fish markets, unregulated chemical use, and weak biosecurity link aquatic pollution with human and animal health outcomes. The introduction of non-native fish species (e.g., tilapia, pangas, carp) and the expanding ornamental fish trade further amplify pathogen risks, facilitating the silent spread of bacterial, parasitic, and fungal agents with zoonotic potential. Climate change, biodiversity loss, and socioeconomic vulnerabilities exacerbate these pressures by destabilizing aquatic ecosystems, reducing resilience, and accelerating AMR dissemination across aquatic, human, and livestock interfaces. By integrating insights from parasitology, microbiology, epidemiology, and environmental science, this review underscores the urgent need for coordinated surveillance, diagnostic capacity, regulatory enforcement, and risk communication strategies. Embedding One Health and climate-smart approaches into fisheries governance is essential to mitigate zoonotic hazards, safeguard food safety, and ensure the long-term sustainability of Bangladesh's aquaculture sector under accelerating environmental change.
Beekeepers in the continental United States cannot obtain USDA organic certification because interim recommendations require more organic-certified land for foraging than is available surrounding most apiaries. To test whether organic farms in the Northeast USA provide sufficient forage for organic honey production, we established 72 colonies using organic management practices on six large organic farms (mean: 1 km2, 249 ac.) in 2023, where natural and seminatural habitats comprised 56-93% of land within a 3 km radius. In 2024, we screened the resulting honey for 96 pesticide residues, compared contamination to 20 brands of store-bought organic and conventional honey, and tested whether landscape composition predicted contamination. Pesticide contamination in honey from Northeast USA organically managed colonies was low, comparable to store-bought certified organic honeys, and lower than conventional honey. Landscape composition did not predict contamination, but may reflect a limited number of sites and narrow range of landscape conditions. Only one sample from Northeast USA organically managed colonies exceeded maximum residue limits (MRLs) for organic honey. These results suggest that organic colony management on farms where natural and seminatural habitats dominate the surrounding landscape (>56%) can produce honey with pesticide contamination comparable to certified organic products. Despite being certified organic, 30% of Hawaiian honeys contained amitraz metabolite residues above MRLs, potentially via in-hive contamination. While the required 6.4 km forage and surveillance zone surrounding apiaries has excluded continental USA beekeepers from organic certification, preventing in-hive chemical contamination may be as important as maintaining organic foraging zones to produce certified organic honey.
Environmental noise is an increasingly urgent environmental health concern in rapidly growing megacities, yet fine-scale spatial data remain scarce in low- and middle-income cities. We developed the first citywide, spatially explicit estimates of environmental sound exposure for Dhaka city proper, the capital of Bangladesh, using long-duration measurements from 67 monitoring sites across the city and land-use regression models. Land-use regression models were developed for average 24-h (LAeq24h), daytime (Lday), nighttime (Lnight), and day-evening-nighttime (Lden) sound levels, with predictors selected through a forward stepwise regression and performance evaluated using cross-validation. Model performance was strong across metrics (cross-validated R2 = 0.66-0.72; RMSE = 3.4-4.3 dBA). Proximity to major transport corridors and vegetation cover (NDVI) explained much of the spatial variability, reflecting the dominance of traffic-related sources within a dense and highly congested urban environment. Predicted sound levels were elevated across Dhaka during both day and night. Modeled estimates suggest that the vast majority of Dhaka residents, approximately 12 million people, are exposed to outdoor sound levels exceeding the World Health Organization-Europe Region traffic guidelines (Lnight: 45 dBA and Lden: 53 dBA), and an estimated 0.9 million residents are exposed to sound levels >70 dBA, a threshold for noise-induced hearing loss. These findings demonstrate pervasively high environmental sound exposure across Dhaka, and provide an empirical basis for urban noise management, policy evaluation, and future epidemiologic research in rapidly urbanizing megacities.
Ghana's 550 km coastline is naturally susceptible to erosion. Yet, the role of mangrove connectivity in mitigating this vulnerability remains poorly quantified, while mangrove deforestation compromises coastal resilience by removing organic barriers that attenuate wave energy and stabilize sediment. This study investigates the spatio-temporal dynamics of mangrove health and shoreline stability in Ghana's Central Region (2005-2025) using Landsat 7, 8, and 9, and Sentinel-2 imagery. Analytical methods included Land Use/Land Cover (LULC) classification, Normalized Difference Vegetation Index (NDVI) to assess vitality, and the Digital Shoreline Analysis System (DSAS) to calculate Linear Regression Rates (LRR). Quantitative results reveal a 59.4% reduction in mangrove area, declining from 46.79% (500.40 km2) in 2005 to 19.05% (203.11 km2) by 2025, occurring alongside a tripling of built-up areas from 14.82% to 38.68%. While linear regression indicated a weak point-to-point relationship between NDVI and LRR (R2 = 0.033,p < 0.001), spatial autocorrelation revealed strong landscape-scale clustering for both shoreline change (Moran's I = 0.69) and mangrove health (Moran's I = 0.91). This suggests that coastal resilience is associated with extensive, contiguous forest patches rather than isolated individuals. These findings suggest that management should shift from reactive hard engineering to nature-based solutions and Integrated Coastal Zone Management (ICZM) that prioritizes habitat connectivity. Conserving connected mangrove ecosystems is essential for effective disaster risk reduction and maintaining Ghana's coastal stability.