The accumulation of heavy metals (HMs) from coal resource exploitation and coal-related industries poses serious ecological and health risks in the hinterland river sediments of Shenfu coal field in Northern China. Using data from 59 samples, the geo-accumulation index and ecological health risks of HMs were assessed probabilistically using Monte Carlo Simulation. Two coupling models were constructed in this study, integrating both the Positive Matrix Factorization and ecological health risk models to identify the risk levels of pollution sources in the Kuye River. The risk of HMs during the wet season was explored due to the lower concentrations and a broader range of pollution sources compared to the dry season. The Igeo value of Hg was greater than 1 in 69% of the samples, suggesting moderately contaminated sediments. According to the source-oriented coupling models (PMF-RI/HRA), coal-mining sources contributed to the overall ecological risk by 48.79%, primarily due to Hg (98.50%). Industrial sources (51.48%) were the largest contributors to carcinogenic risk, with Ni corresponding to the target HM. This indicated that different HMs originating from distinct pollution sources were responsible for ecological or carcinogenic health risks. The probabilistic health risk evaluation results indicated that children faced higher risks than adults, with over 94.07% of carcinogenic risks exceeding thresholds. Traffic sources followed, contributing 34.41% to ecological and 41.09% to carcinogenic risks. The results highlight the priority sources and target HMs based on specific sources in the mixed 'mining-industrial-traffic' areas, providing valuable insights for environmental protection and the development of risk prevention strategies in a typical energy industry area.

ABSTRACTUnderstanding the mechanisms of species coexistence is a long‐standing goal in community ecology. The performance of woody seedlings across different ecological niches has been proposed as a key mechanism in community assembly. Factors influencing seedling survival can be revealed by analyzing neighboring plants in conjunction with their phylogenetic relatedness, functional traits, and the surrounding environment. In the present study, we conducted a seasonal analysis of 936 seedlings for 56 species from a 4‐ha subtropical forest over 3 years in the Gaoligong Mountains, Southwest China. Our aims were to examine the relative effects of neighbor density, habitat conditions, and seasonal climate variability on seedling survival during dry and rainy seasons, and to determine whether the sensitivity of seedling survival responding to neighbor densities and abiotic factors differs between seasons. The findings indicated that the relative importance of neighbor densities, habitat factors as well as seasonal rainfall on seedling survival varied with seasonality. During the rainy season, seedling survival was comparatively less affected by conspecific neighbor density and was mainly negatively influenced by rainfall, whereas habitat factors (including topography, soil properties, and canopy openness) were detrimental for survival to a lesser extent. There is evidence suggesting that phylogenetic negative density dependence (PNDD) and functional negative density dependence (FNDD) are more pronounced in the rainy season. In contrast, the positive effect of canopy openness was more important during the dry season. Our findings further revealed that the effects of PNDD, FNDD, canopy openness, and seasonal rainfall varied widely among species across seasons. Moreover, species differed in their ability to respond to the trade‐offs between canopy openness and rainfall in relation to phylogenetic relatedness and functional dissimilarity during the dry and rainy seasons. Overall, our results demonstrate that seasonality modulates the strength and importance of phylogenetic and functional density dependence, habitat preference, and climate for seedling survival in subtropical forests. The seasonal variations in these effects allow species to maintain coexistence across dry and rainy seasons. Consequently, seasonal variability should be accounted for in future studies in understanding the diversity of forest communities.

Malaria overdiagnosis contributes to misuse of antimalarials and mistreatment of other illnesses. Although the DRC's national guidelines mandate rapid diagnostic tests (RDTs) for malaria testing and treatment, healthcare providers overreport malaria cases compared to the proportion of positive tests interpreted and recorded by an automated Deki reader and uploaded to a cloud server. Significantly higher test positivity rates (TPRs) are reported through the national Health Management Information System (HMIS) compared to the Deki reader database, especially in the dry season. Understanding the reasons behind malaria overdiagnosis and overreporting is important for providing appropriate treatment and avoiding antimalarial over-prescription. This qualitative study explores factors influencing provider nonadherence to malaria RDT results. Sixty-four semi-structured interviews were conducted with staff at 16 primary-level health facilities in Kasai Central and Haut Katanga provinces. Twelve key informant interviews with health officials and 24 focus groups with community members provided additional context. Providers and health facility supervisors were less likely to trust RDT results when they were negative than positive. To many providers, fever was synonymous with malaria and a positive RDT provided confirmation of their presumptive diagnosis while a negative RDT challenged it. To integrate the negative RDT into their existing mental model, providers explained how RDTs could return false negative results. Explanations for why RDTs may be inaccurate included that improperly treated malaria can result in a negative test, RDTs are negative early in infection, RDTs do not capture all malaria species, and the wide range in RDT accuracy. Providers and technical personnel noted financial incentives to carrying out microscopic examination rather than RDTs as per DRC's national guidelines. Guidance communicated to service providers in high-endemic, low-resource malaria settings prior to RDT availability, such as presumptive treatment of all fevers as malaria, leads providers to oppose basing treatment decisions on RDT results. Sharing data on RDT efficacy at the country level could increase confidence in RDT results, and better understanding of how RDTs work and what they measure would dispel misconceptions about false negatives. Better oversight of facility-level data, and comparisons with neighboring facilities, could improve adherence to national guidelines in the DRC.

Insecticides in water and sediments of the tropical river in Hainan Province, China: Occurrence, migration, risk assessment, and effects on environmental factors.

Spatio-temporal dynamics and flux of microplastics in the lower Ganges-Brahmaputra-Meghna River system and estuary.

The spatiotemporal distribution, partitioning, and prioritization of current use pesticides (CUPs) in aquatic environment of Pearl River Delta.

ABSTRACT This study assessed variations in water quality at the Indus River Basin (IRB) impacted by wastewater (WW) drains from five densely populated urban and industrial cities: Lahore, Faisalabad, Multan, Sukkur, and Hyderabad. Water samples from the barrages at upper and lower IRB, tributaries, and cities' WW drains were analyzed. GIS‐based mapping was used to visualize the transport of pollution from the WW drains to the riverine bodies, identifying potential source cities and pathways of pollution. Employing sensitivity analysis through various models and validation matrices enhances the statistical reliability of hotspot mapping water quality variations. The riverine samples from the upper basin exhibited relatively good water quality with low COD and TOC levels. However, the COD levels at the Balloki and Panjnad barrages downstream of the Ravi and Chenab exceeded 160 mg/L. The analyzed WW drains in Lahore and Faisalabad discharged into the Ravi River and recorded high COD and TDS levels up to 600 and 4000 mg/L, respectively. Drains from the downstream Hyderabad region worsened contamination, with COD reaching 198 mg/L. Seasonal assessments revealed elevated pollutant concentrations during the dry season, with COD and TDS levels increasing by 1.68 and 1.58 times, respectively, compared to the wet season.

Microbial mediators of environmental change in the Yellow River basin: Flavobacterium and pollution dynamics during the dry season.

Illegal gold mining filters soil bacterial communities and enhances mercury mobility across Brazilian biomes: A multi-season study.

Seasonal dynamics of sedimentary dissolved organic matter in plateau lakes: Driving effects on microbial community and functional genes in elements cycling.

Bioconversion of heavy metals in river sediments: Seasonal dynamics, driving mechanisms, and BSAF-based assessment in the Liujiang River basin.

Box-modelling of HOx in Mexico City.

This study examined the role of dry-season vegetable irrigation farming in enhancing food security in the Nanumba South District, using the Wulensi community as a case study. Guided by a qualitative research design, the study employed a case study approach and collected data from 15 purposively selected respondents, including dry-season farmers and agricultural officers. Data were gathered through in-depth interviews and focus group discussions, and were analysed thematically. The findings reveal that dry-season irrigation farming is widely practised in Wulensi and contributes significantly to household food security by improving food availability, generating income, and supporting livelihood diversification during the dry season. Despite these benefits, the study identified multiple constraints that undermine the sustainability of irrigation farming. These include water scarcity, limited access to modern irrigation technologies, high input costs, pest and disease infestations, market challenges, inadequate agricultural extension support, and financial barriers. Respondents proposed several feasible strategies to address these constraints, such as rehabilitating water infrastructure, improving access to irrigation technologies, strengthening extension services, expanding credit facilities, forming farmer cooperatives, and improving market access mechanisms. The study concludes that implementing these strategies could substantially improve the productivity and sustainability of dry-season irrigation farming, thereby contributing to long-term food security in the Wulensi community.

Indoor dust serves as a medium for the deposition of heavy metals, and young children's rapid physical growth and hand-to-mouth behavior expose them to the impacts of heavy metals. This project aimed to measure the concentrations of heavy metals in classroom dust from the selected preschools in southwestern Nigeria. Dust samples were taken via a dust collector and analyzed quantitatively and qualitatively via the Atomic Absorption Spectroscopy (AAS) scheme. The descriptive and inferential statistical method was employed for the data analysis, and standard calibration, recovery analysis, and blank determination were carried out for the quality control measures. It was found that, in the dry season, the total metal concentrations in dust were 1.82 gg-1 Cu to 80.00 gg-1 Zn, whereas, in the wet season, the heavy metal concentrations were 0.83 gg-1 Co to 38.43 gg-1 Zn. Hence, the selected preschool dust was significantly enriched with high levels of Cd and As contamination but unpolluted for Co, Cu, Mn, and Pb across all examined metals. The results indicate elevated concentrations of lead (Pb) and cadmium (Cd) in high-traffic indoor spaces, with levels exceeding recommended safety thresholds. Lead (Pb) exposure is linked to neurodevelopmental disorders and reduced cognitive function, Cadmium (Cd) can cause kidney damage and impair bone development, while arsenic (As) is associated with immunotoxicity and an increased risk of cancer. To mitigate these risks, this study recommends practical measures, including frequent wet cleaning of floors and surfaces to reduce dust accumulation and limiting the use of materials known to contain heavy metals, such as lead-based paints and older plumbing fixtures.

Nonnegligible migration of rubber-derived chemicals from road surface to adjacent greenbelt soil.

Seasonal and dietary determinants of metal and metalloid exposure in riverine communities of the Brazilian Amazon: A study on temporal variation.

The present study aims to assess the ecological status of Sectors IV and V of the Ébrié Lagoon using zooplankton functional groups at five sampling stations located in these sectors. Zooplankton was sampled monthly over a one-year period in the Ébrié Lagoon using a plankton net with a 64-µm mesh size. Physicochemical parameters were measured using a multiparameter probe. Water samples for nutrient analysis were collected using a 2.5 L Niskin bottle. Nutrient concentrations were determined in the laboratory using a UV 2700 molecular absorption spectrophotometer. A total of 48 zooplankton species belonging to three taxonomic groups (rotifers, copepods, and cladocerans) were identified in the Ebrié Lagoon and classified into five functional groups (RF, RC, SCF, MCF, and MCC). The low spatial and seasonal variability of environmental parameters and functional group biomass suggests a relatively homogeneous ecological structure across the lagoon. Zooplankton functional group densities did not differ significantly between the rainy (45.11 ind. L⁻¹) and dry seasons (54.88 ind. L⁻¹). During the rainy season, the highest densities were observed for small-sized filter feeders (SCF) at Mopoyem (28.31 ind. L⁻¹), while during the dry season, maximum values were recorded for filter-feeding rotifers (RF) at Layo (17.3 ind. L⁻¹). Phosphate and nitrate concentrations were positively associated with RF and medium-sized carnivorous copepods and cladocerans (MCC), whereas SCF were mainly influenced by ammonium concentration and water depth. This functional approach improves understanding of trophic dynamics and ecosystem functioning in tropical lagoons and provides a valuable baseline for future ecological monitoring and management.

Feed shortage has been identified to be one of the main constraints limiting animal production for milk and meat in Niger. Stover from cereal crops has been a significant source of feed during the long and dry season with producers showing preference for sorghum stover. Sorghum brown midrib (bmr) genes are well known for improving forage quality around the world; however, farmers in Niger do not have access to sorghum cultivars enriched with bmr genes. To address this limitation, a new forage sorghum breeding program has been initiated in 2016 in Niger to introgressbmr genes into elite Nigerien sorghum varieties. Agronomic studies were performed to determine the most efficient forage production system using split plot design for three treatments: TRT 1, TRT 2 and TRT 3. The data collected were subjected to analysis of variance and Tukey HSD multiple range test was used to separate treatment means.NIRSanalysis revealed the good nutritional qualities of the TRT-1 and TRT-2and significant (P<0.05) differences were observed among treatments for CP, and ADL contents. The stover from the TRT-1 expressed high nutrients content levels. The double cutting technicopens new opportunities for alleviating feed shortage facing improved livestock productivity in Niger.

Abstract Bacterial wilt caused by Ralstonia solanacearum is a major threat to global tomato production. Two field trials were conducted in 2023 (wet season) and 2024 (dry season) at the Federal University of Kashere, Gombe State, to evaluate the use of neem leaf powder in the management of bacterial wilt of tomato. The experiment was conducted using a randomized complete block design with three replications. Neem leaf powder ( Azadirachta indica ) was applied to two tomato cultivars, ‘Tandino’ and ‘Dan Syria’, at 15, 30, and 45 g, while untreated (0 g) and streptomycin-treated plots served as negative and positive controls, respectively. Application of streptomycin and 45 g of neem leaf powder 9 weeks after transplanting showed population densities of 1.5 and 1.4 total cfu·g −1 soil (2023) and 1.4 and 1.0 cfu·g −1 soil (2024), which were significantly lower than the population densities of 8.6 (2023) and 8.0 (2024) cfu·g −1 soil recorded in untreated plots. After application of streptomycin and 45 g of neem leaf powder, wilt severity scores of 0.7 and 1.3 (wet season) and 0.7 and 1.0 (dry season) were observed, which was significantly lower than 5.0 in each season in untreated plots. Application of 45 g neem leaf powder resulted in a yield of 432.4 and 437.4 g of fruit per plant, which was significantly higher than the 2.8 and 2.4 g on untreated plots in 2023 and 2024, respectively. It was found that application of 45 g of neem leaf powder can reduce the severity of bacterial wilt in tomatoes and thus increase fruit yield.

Wind nullity, low wind, and bi- or multi-modality are common characteristics at high temporal resolution, especially in Equatorial regions. The traditional two-parameter Weibull (Weibull) distribution function (DF) is not designed to capture such peculiarities. Hourly mean wind speed data for eight locations that cut across different climate zones in an Equatorial region of West Africa have been analyzed using Weibull and Maximum Entropy Principle-based (MEP) distribution functions (DFs). Wind characteristics, such as power density, null wind speed, and modal distributions, together with turbine efficiency, capacity, and availability factors, were also assessed at a wind turbine hub height of 73 m using standard statistical tools. The results indicated that null wind speed and/or bimodality were present in the wind distributions at Abuja, Akure, Akungba, Nsukka, Makurdi, and Yola. The results of the assessments of the two DFs show that the MEP DF generated much better results across all time scales (R2: 0.83 - 0.98; RMSE: 0.0037 - 0.0109 m/s2) than the Weibull DF (R2: 0.47 - 0.98; RMSE: 0.0038 - 0.0191 m/s2), especially for locations where null wind speed and bimodality were prominent in the wind data distribution. MEP DF results further indicated that annual and rainy season periods were better modeled than the dry season in all the locations. The overall effect of all the turbine characteristics on annual and seasonal scales is that sufficient winds were available (Availability factor: 0.733 - 0.97; Capacity factor: 0.350 - 0.778) at the rated power for energy production in all the climate zones.