Anthropogenic Influences Research Articles

A review of soil moisture data in China: definition, sources, and applications in hydrometeorology research

Abstract Soil moisture (SM) is a key land surface hydrological variable that regulates energy, water, and carbon exchanges between land and atmosphere, as well as connecting hydrological, meteorological and environmental sciences. For decades, SM has been measured, simulated, and then utilized for various research in China. In this paper, we summarize recent progresses of SM data and their hydrometeorological applications in China and then propose some future research prospects. First, we introduce the terminology and description of SM in various formats, followed by the primary SM data sources along with their strengths and weaknesses. Then, recent advances in SM applications for drought detection, land-atmosphere interactions, and climate prediction are thoroughly discussed. Based on the above findings, it is recommended that: (1) future developments of SM data should undertake more intensive in-situ measurements, carry out high-quality modeling experiments along with upgraded numerical models, and build novel data fusion technology; (2) ongoing efforts should be emphasized on enhancing representation of SM-related physical processes and taking into account the anthropogenic influences on SM in the land surface models; (3) SM drought should reinforce its onset and demise mechanisms, as well as its precursor signals in both terrestrial and atmospheric systems; and (4) more innovative methods are needed to distinguish the impacts of SM on climate variability from other drivers. With these efforts, research on SM would help us to understand the mechanisms underlying its interconnected changes in the earth system.

First online observations of greenhouse gases over the Central Himalayas: insights in fluxes, vegetation links, and meteorological controls.

Ground observations with diurnal variability over the Himalayas are crucial to validate climate mitigation efforts, build accurate emissions inventories, and better forecasting. This study bridges the acute scarcity of such measurements by making the first online observations of CO2 and CH4 with CO at a mountain site (Nainital, 29.4° N, 79.5° E, 1958m a.m.s.l.) continuously for 5years in the Central Himalayas. Observed levels of CO2 and CH4 are higher than those at other background sites. The boundary layer evolution and upslope winds determine the diurnal pattern of CH4 and CO, while CO2 diurnal and seasonal variations are governed by biospheric uptake. Bivariate analysis shows that higher levels (> 1.98ppm) of CH4 are mostly localized and that the distribution of CO2 is representative of the terrestrial ecosystem. Diurnal variations in CO2 relate to the meteorology, except during spring when the anthropogenic influence breaks this covariation. Excess and background CO2 and CH4 are segregated, and the role of biomass burning in spring and fossil fuel combustion in raising CO2 is revealed. The role of vegetation is also evaluated with the Normalized Difference Vegetation Index (NDVI) and fluxes from the CarbonTracker model. During autumn, the impact of agricultural and waste emissions on high CH4 is evidenced. The limited online observations from this region also showed an increasing trend in CO2 (2.66 ± 0.17ppmyr-1) and CH4 (9.53 ± 0.09ppbyr-1), while CO has a decreasing trend (3.15 ± 1.32ppbyr-1). The results highlight the complex interplay of anthropogenic emissions, biospheric uptake, and weather patterns with mountain features in shaping CO2 and CH4 levels, especially at the diurnal scale.

Structure, Toxicity, Prevalence, and Degradation of Six Understudied Freshwater Cyanopeptides

Anthropogenic influences have increased global warming and eutrophication, escalating the frequency and severity of harmful cyanobacterial blooms (cHABs) in freshwater ecosystems. These blooms release cyanopeptides, a diverse class of bioactive compounds with varying acute and chronic toxicities upon ingestion. To date, research has prioritized acutely toxic cyanopeptides like microcystins. As a result, significantly less is known about other freshwater cyanopeptides. This review highlights six understudied cyanopeptide classes, anabaenopeptins, cyanopeptolins, aeruginosamides, aeruginosins, microginins, and cyclamides, and provides a comprehensive overview of their molecular structures, toxicological profiles, environmental concentrations, and known degradation pathways. Given the potential toxicity, increased environmental abundance, and environmental stability of many cyanopeptides in freshwater sources, further research is needed to understand if degraded cyanopeptides are still biologically active prior to entering drinking water to ensure public health.

Remote Alpine Lakes and Microplastic Accumulation: Insights from Sediment Analysis of Lake Cadagno

Microplastic (MP) occurrence is a growing concern in environmental research, with significant attention focused on its presence in various ecosystems worldwide. While much research has centered on large lakes and water bodies, remote alpine lakes remain relatively unexplored in terms of microplastic occurrence. Studying microplastic occurrence in remote alpine lakes is important to understand the global spread of pollution, assess its impact on pristine ecosystems, and inform conservation efforts in these vulnerable environments. This study investigates microplastic presence in the sediment of Lake Cadagno, a remote alpine lake situated in the Piora Valley of southern central Switzerland. The lake has no effluents, and its meromictic nature means that the water on the bottom is not mixed with the water above, which can potentially lead to an enhanced accumulation of microplastics in the sediments that perpetuate in the lake system. Through sediment core sampling and analysis, we aim to identify the sources and deposition trends of microplastics in this pristine alpine environment. Our findings reveal the presence of microplastic within Lake Cadagno: in total, 186 MP particles were extracted from 756 cm3 of processed sediment (0.24 MP/cm3) with an average of 19.5 MP/sample (SD ± 11.8 MP/sample). Our results suggest that microplastics are predominantly attributable to localized sources associated with nearby human activities. The absence of synthetic fibers and the limited polymer types detected suggest a minimal contribution from atmospheric deposition, reinforcing the significance of local anthropogenic influences. Spatial clustering of microplastic particles near potential sources underscores the impact of surrounding land use activities on microplastic distribution. Overall, this study highlights the importance of addressing microplastic contamination even in remote and relatively unmodified ecosystems like Lake Cadagno, to elucidate the need for strict adherence to waste management and correct disposal actions to reduce the impacts of microplastic contamination.

Holiday Effect of Ozone Pollution in China

Over recent decades, China has achieved significant progress in reducing haze pollution, yet photochemical pollution, primarily characterized by elevated ozone (O3) levels, has intensified, posing severe ecological and public health risks. The “holiday effect”—periodic changes in human activities during holidays such as weekends and the Spring Festival—provides a critical lens to evaluate anthropogenic influences on O3 pollution, particularly under scenarios of reduced anthropogenic emissions driven by the carbon neutrality pledge. However, a comprehensive summary of this phenomenon remains lacking. This review systematically examines spatial–temporal variations and driving factors, including precursor emissions, atmospheric oxidation capacity (AOC), and meteorological conditions, of the holiday effects across China. Key findings reveal that reduced nitrogen monoxide during holidays weakens its titration effect on O3. Additionally, decreased particulate matter on holidays leads to improved atmospheric visibility and a corresponding enhancement in AOC and biogenic volatile organic compound emissions, all of which boost the photochemical formation capacity of O3. Furthermore, solar radiation and temperature positively correlate with O3 pollution during holidays, whereas rainfall and cloud cover suppress it. This review also provides suggestions for future research regarding mechanistic studies on photochemistry, machine learning for pollution drivers, radical roles in O3 formation, and health impact assessments.

Anthropogenic influence has intensified the severity of summer compound hot and drought events over Xinjiang, China

Anthropogenic influence has intensified the severity of summer compound hot and drought events over Xinjiang, China

Spatiotemporal dynamics of Ramsar wetlands and freshwater resources: Technological innovations for ecosystem conservation.

Aquatic ecosystems, particularly wetlands, are vulnerable to natural and anthropogenic influences. This study examines the Saman Bird Sanctuary and Keetham Lake, both Ramsar sites, using advanced remote sensing for water occurrence, land use and land cover (LULC), and water quality assessments. Sentinel data, processed in cloud computing, enabled land-use classification, water boundary delineation, and seasonal water occurrence mapping. A combination of Modified Normalized Difference Water Index (MNDWI), OTSU threshold segmentation, and Canny edge detection provided precise seasonal water boundaries. Study utilized a combination of the MNDWI, OTSU threshold segmentation, and Canny edge detection methods. These approaches allowed for precise delineation of seasonal water boundaries. Sixteen water quality parameters including pH, turbidity, dissolved oxygen (DO), chemical oxygen demand (COD), total hardness (TH), total alkalinity (TA), total dissolved solid (TDS), electrical conductivity (EC), phosphates (PO4), nitrate (NO3), chloride (Cl-), fluoride (F-), carbon dioxide (CO2), silica (Si), iodine (I-), and chromium (Cr-) were analyzed and compared for both sites. Results showed significant LULC changes, particularly at Saman, with scrub forest, built-up areas, and agriculture increasing, while flooded vegetation and open water declined. Significant LULC changes were observed near Marsh wetland, where positive changes up to 42.17% were seen for built-up in surrounding regions, with an increase to 5.43 ha in 2021 from 3.14 ha in 2017. Positive change was observed for scrub forests up to 21.02%, with a rise of 2.18 ha. Vegetation in the marsh region, including seasonal grasses and hydrophytes, has shown an increase in extent up to 0.39 ha with a rise of 7.12%. Spatiotemporal water occurrence was analyzed across pre-monsoon, monsoon, and post-monsoon seasons using Sentinel-1 data. The study highlights the role of remote sensing and field-based water quality monitoring in understanding ecological shifts and anthropogenic pressures on wetlands. By integrating land-use changes and water quality analysis, this research provides critical information for planning and conservation efforts. It provides vital insights for conservation planning, advocating for continued monitoring and adaptive management to sustain these critical ecosystems. PRACTITIONER POINTS: Spatiotemporal surface water occurrence at two geographically different wetlands-lake and marsh wetland; LULC and its change analysis to evaluate the impact on wetlands and its surrounding environment-positive and negative changes; Boundary delineation to examine changes and identify low-lying areas during the pre- and post-monsoon; Comparative analysis of the water quality of two different wetlands; Insectivorous plant-Utricularia stellaris, was recorded from Northern India at the Saman Bird Sanctuary for the first time.

Environment, Occupation, and Chronic Maxillary Sinusitis in Pre-Roman Italy.

To assess the frequency of chronic maxillary sinusitis (CMS) in a pre-Roman archeological skeletal assemblage from Italy and to evaluate the occurrence of CMS in combination with its environmental and sociocultural context. A total of 131 adult individuals from the pre-Roman site of Pontecagnano (eighth to third centuries bce) in southern Italy with intact maxillary sinuses of ≥ 50% preservation were macroscopically and microscopically observed for the presence of osseous changes per published diagnostic criteria of CMS. CMS was present in 57.2% of individuals. The prevalence of CMS was higher in females than in males, and this difference was statistically significant (p = 0.043). The frequency of CMS increased with age-at-death. Bilateral CMS occurred more frequently than unilateral CMS. The differences in the prevalence of CMS in the Etruscan (700-450 bce), Samnite (450-375 bce), and final pre-Roman (375-200 bce) phases of occupation were not statistically significant. In combination with viral and bacterial infections, occupational activities (metallurgy, ceramic and textile production, and agriculture) and environmental factors (volcanic ash, marshy environments, and sub-Saharan dust plumes) likely stimulated respiratory disease and resultant CMS in the inhabitants of Pontecagnano. This study provides a framework for future research on CMS and respiratory diseases in the Mediterranean region, in relation to environmental, climatic, and anthropogenic influences. The limited number of individuals per period prevented a proper diachronic analysis. Osteoarcheological assemblages from the Mediterranean region should be systematically analyzed for CMS to increase understanding of how climate, environment, industrialization, and urbanicity affected human health through time.

Unraveling the fate of phosphorus in alluvial aquifers of the middle-lower Yellow River: Coupled natural and anthropogenic impacts.

Unraveling the fate of phosphorus in alluvial aquifers of the middle-lower Yellow River: Coupled natural and anthropogenic impacts.

Use of multi-resolution, three-dimensional hydrodynamic and water-quality models to assess response to nutrient load reductions in Barnegat Bay-Little Egg Harbor estuary, New Jersey, USA.

Use of multi-resolution, three-dimensional hydrodynamic and water-quality models to assess response to nutrient load reductions in Barnegat Bay-Little Egg Harbor estuary, New Jersey, USA.

Using Salinity, Water Level, CFCs, and CCl4 to Assess Groundwater Flow Dynamics and Potential N2O Flux in the Intertidal Zone of Sanya, Hainan Province: Implications for Evaluating Freshwater Submarine Groundwater Discharge in Coastal Unconfined Aquifers

This study combines field and laboratory analyses from seven shallow wells (ZK1 to ZK7) positioned perpendicular to the coastline to investigate groundwater discharge and dynamics in the coastal unconfined aquifer of the intertidal zone at Yazhou Bay, Sanya, Hainan Province. The research highlights spatial variations in N2O concentration, temperature, electrical conductivity (EC), pH, and the distribution of CFCs and CCl4 in shallow groundwater, utilizing samples from wells ZK1 to ZK7 and seawater collected near ZK1. Key findings indicate that groundwater temperature decreases toward the ocean, while EC exhibits a stepwise increase from land to sea, with a sharp transition near ZK3 marking the freshwater–saltwater mixing zone. pH values are lowest in ZK3 and ZK4, gradually rising both inland and seaward. N2O concentrations in the shallow wells (ZK1–ZK7) are divided into two distinct groups: higher concentrations (9.69–57.77 nmol/kg) in ZK5–ZK7 and lower concentrations (6.63–23.03 nmol/kg) in ZK1–ZK4. Wells ZK3 and ZK4 show minimal variation in CFC-11 and CFC-113 concentrations, suggesting they represent a transition zone that likely delineates groundwater flow paths. In contrast, significant concentration differences in wells ZK5–ZK7 (north) and ZK1–ZK2 (south) reflect the influence of aquifer structure variability, recharge sources, and local hydrogeochemical conditions. CFC-12 concentrations exhibit a clear freshwater–saltwater mixing gradient between ZK3 and ZK1, with higher concentrations in freshwater-dominated areas (ZK3–ZK7) and lower concentrations near seawater (ZK1). CCl4 concentrations at ZK7 and ZK3 differ markedly from other wells, indicating unique hydrogeochemical conditions or localized anthropogenic influences. A model for the formation of upper saline plumes (USP) under tidal forcing at the low tidal line was established previously. Here, we establish a new model that accounts for the absence of USP driven by hydrological processes influenced by artificial sandy beach topography, and a fresh groundwater wedge is identified, which can serve as a significant fast-flow pathway for terrestrial water and nutrients to the ocean.

Accuracy Evaluation of a Wave Monitoring System by Testing the Hydraulic Performance of Portable Low-Cost Buoys

Lakes are complex ecosystems affected by various anthropogenic influences, including vessel-induced waves. Detecting these waves by a micro-electro-mechanical system (MEMS)-based inertial measurement unit (IMU) equipped on a buoy-based monitoring system can help assess their impacts and support developing sustainable water ecosystem management. This study evaluated and optimized the measurement accuracy of a wave-monitoring system designed to detect waves generated by recreational vessels on lakes. In laboratory tests, we analyzed and, separately, compared the hydraulic behavior of different buoy configurations and assessed the IMU integration in field test campaigns. Results showed that all tested buoys exhibited a mean average absolute deviation (AAD) of less than 20 mm, while the IMU integration achieved an overall AAD of 1.9 mm. For small waves, characterized by wave heights < 50 mm, the IMU’s AAD corresponds to the buoy’s AAD. However, for larger waves, the buoy’s AAD often significantly exceeds that of the IMU, indicating that the hydraulic performance of the buoy limits measurement accuracy in case of greater waves. The best-performing buoy configuration in laboratory tests achieved a measurement accuracy (mean AAD) below 10 mm (or 10% of wave height), confirming the suitability of the developed wave buoys for a vessel-induced wave-monitoring system on lakes.

A call for increased integration of experimental approaches in movement ecology.

Rapid developments in animal-tracking technology have enabled major advances in the field of movement ecology, which seeks to understand the drivers and consequences of movement across scales, taxa, and ecosystems. The field has made ground-breaking discoveries, yet the majority of studies in movement ecology remain reliant on observational approaches. While important, observational studies are limited compared to experimental methods that can reveal causal relationships and underlying mechanisms. As such, we advocate for a renewed focus on experimental approaches in animal movement ecology. We illustrate a way forward in experimental movement ecology across two fundamental levels of biological organisation: individuals and social groups. We then explore the application of experiments in movement ecology to study anthropogenic influences on wildlife movement, and enhance our mechanistic understanding of conservation interventions. In each of these examples, we draw upon previous research that has effectively employed experimental approaches, while highlighting outstanding questions that could be answered by further experimentation. We conclude by highlighting the ways experimental manipulations in both laboratory and natural settings provide a promising way forward to generate mechanistic understandings of the drivers, consequences, and conservation of animal movement.

Tropical watershed management: understanding the relationship between land use and pesticide pollution in Chanchaga River

Freshwater ecosystems are vulnerable to various land use impacts, resulting in concern for aquatic biota and humans. Understanding the occurrence of pesticide contamination is necessary to safeguard aquatic biodiversity and human health. We hypothesize that sub-catchments with a higher proportion of agricultural activities have a higher concentration of pesticides in the water sample. Our study assessed the nexus between land uses and pesticide contamination in three zones of the Chanchaga River, namely, a control site, an agricultural area (S1), and an urban area (S2). Various classes of land use around the catchment were determined using ArcGIS 10.8 GIS software. At the same time, analysis of pesticide residues was carried out using the liquid–liquid extraction method, followed by gas chromatography–mass spectrometry. A total of 10 herbicides and 12 insecticides were recorded in each sampled sub-catchments, with a statistically significant difference across the sampled sub-catchments. Sampled sites in agricultural and urban areas had higher concentrations of pesticide residues than the control zone, with less anthropogenic influence. Redundancy analysis revealed farming and urbanized land use were the main sources of pesticide contamination in the waterbody. Pesticides may have chronic or acute impacts on aquatic biodiversity and a higher trophic effect on human health. It was evident that all sampled sub-catchments had pesticide concentrations exceeding the WHO permissible limit for human consumption. Prioritizing alternative methods to pesticides for managing pests and weeds is crucial for sustainable agriculture and environmental sustainability.

Long-term dynamics and driving mechanisms of plant communities in a temperate estuary in eastern China based on pollen analysis: a case study of the Liaohe Estuary.

The Liaohe Estuary, a representative estuarine ecosystem in eastern China, has experienced significant shifts in plant community characteristics due to climate change and anthropogenic influences in recent decades. This study employed sediment 210Pb dating, pollen analysis, and environmental factor indicators to comprehensively assess the composition, trends, and drivers of plant communities in the Liaohe Estuary from 1944 to 2022. The findings revealed that herbaceous plants dominated the estuary's vegetation under a cool and humid climate, though humidity exhibited a declining trend over time. Between 2001 and 2022, pollen concentration and herbaceous plant prevalence increased significantly. Key environmental drivers-mean annual temperature (MAT), salinity, grain size, pH, and agricultural production-were strongly correlated (p < 0.001) with plant community dynamics. Natural factors (grain size, salinity) enhanced the dominance of key species but reduced overall pollen concentration. Conversely, agricultural activities diminished dominant species proportions while increasing pollen concentration. These results highlight the dual influence of climatic and anthropogenic factors on estuarine vegetation. The study provides a theoretical basis for restoring degraded estuarine ecosystems.

Anthropogenicity, Potential Contamination Index (Cp) and Geo-Accumulation Index (I-geo) Analysis of Sediments of Kaani River, Ogoni Axis, Rivers State, South-South, Nigeria

Modifications in the natural state of the environment brought about by human activity have resulted in pollution or contamination at various degrees. Because of their toxicity and tendency to accumulate, heavy metals are extremely important to the environment. It is critical that their quantities in the marine ecosystem of our surroundings be monitored. Anthropogenicity, possible contamination, and geo-accumulation index were assessed using sediment samples taken from four (4) distinct geographic locations along the Kaani River in the Ogoni axis of Rivers State, Nigeria, in accordance with international standards. Atomic Absorption Spectrophotometric technique (AAS) was used to determine the heavy metal content of the sediments. The sequence of the heavy metal concentrations, according to the analysis&amp;apos;s findings, was Fe &amp;gt; Zn &amp;gt; Mn &amp;gt; Cu &amp;gt; Cd &amp;gt; Pb &amp;gt; As. According to the recorded data, Zn &amp;gt; Ni &amp;gt; Cu &amp;gt; Cd &amp;gt; Pb &amp;gt; Cr &amp;gt; As &amp;gt; Mn &amp;gt; Fe was the order of anthropogenic influence or addition of the heavy metals under investigation to the sediments. According to the percentage values, Zn had the largest anthropogenic input in the Kaani River sediments, followed by Ni and Cu. Fe &amp;gt; Zn &amp;gt; Ni &amp;gt; Cu &amp;gt; Cd &amp;gt; Pb &amp;gt; Cr &amp;gt; As &amp;gt; Mn is the order in which the potential contamination index analysis is presented. Sediment heavy metals from Maa di binnise Igbara waterside (station 1), Mann Stream (station 2), Woman Stream (station 3), and Nwii ke ma kor stream (station 4) were found to be extremely contaminated with Zn, slightly contaminated with Cu and Cd (at some stations), and uncontaminated with Fe, Mn, Pb, and As according to Geo-accumulation index values. Even at low concentrations, these observations unequivocally point to an imbalanced state in the ecosystem. In order to restore the aquatic ecosystem&amp;apos;s integrity and sufficiently safeguard the quality of its sediment, a controlled effort must be made to limit the detrimental effects of these trace elements.

The Aerosol Optical Properties over a Desert Industrial City Wuhai, Northwest China, During the 3-Year COVID-19 Pandemic

Aerosol optical depth (AOD) data from 2020 to 2022 during the COVID-19 pandemic in a typical desert industrial city, Wuhai, was analyzed to investigate aerosol optical properties, origins of different types of aerosols, and the impacts of the COVID-19 lockdown on desert pollution. Results show that annual AOD (500 nm) and Ångström exponent α were 0.36 ± 0.12 and 0.75 ± 0.22 in 2020, 0.30 ± 0.12 and 0.75 ± 0.14 in 2021, and 0.28 ± 0.09 and 0.74 ± 0.19 in 2022, respectively, representing a slightly polluted environment characterized by a mixture of coarse-mode dust aerosols and fine-mode anthropogenic aerosols. Seasonal analysis reveals that the highest AOD primarily occurred in spring due to frequent dust events, while the lowest AOD was observed in winter. Potential Source Contribution Function (PSCF) identified the Alxa Desert as a major potential source during the entire year, and anthropogenic industrial and mining activities in northern Ningxia and southern Inner Mongolia were also important contributors, particularly outside of the winter season. The prevailing wind direction in Wuhai was from the northwest (NW-quadrant), originating from the depopulated desert or Gobi area, accounting for 85.11% in spring, 61.45% in summer, 68.09% in autumn, and 100% in winter. The remaining air masses came from southeastern (SE-quadrant) densely populated areas. Despite the dominance of NW air flows, SE anthropogenic air masses resulted in the highest AOD of 0.47 ± 0.24 in spring, 0.38 ± 0.23 in summer, and 0.32 ± 0.17 in autumn, with corresponding finest particle sizes of 0.83 ± 0.31, 0.91 ± 0.30, and 1.02 ± 0.22 in α. This suggests that anthropogenic influence remains significant even under strict control measures during the COVID-19 lockdown. In winter, the northwest air masses contributed to the highest pollution of 0.49 ± 0.39 (AOD) and finest particle size of 0.90 ± 0.32 (α), likely associated with the coal/straw burning for winter heating. In addition, the particles leading to moderate pollution primarily ranged around 0.2–0.25 µm, and fine particle pollution persists throughout the year.

Bayesian-optimized recursive machine learning for predicting human-induced changes in suspended sediment transport.

The suspended sediment load (SSL) of a river is a key indicator of water resource management, river morphology, and ecosystem health. This study analyzes historical changes in SSL and evaluates machine learning (ML) models for SSL prediction in the Godavari River Basin. The dataset was divided into pre-1990 (1969-1990) and post-1990 (1990-2020) periods, revealing a significant decline in mean annual SSL from 136.85 to 62.38 million tons post-1990 due to anthropogenic influences such as dam construction and land-use/land-cover (LULC) changes. Despite a consistent seasonal distribution (~ 73% SSL contribution from monsoon months in both periods), there was a notable decline in median and peak SSL values, along with a narrowing interquartile range, indicating reduced sediment availability. The empirical cumulative distribution function (ECDF) further revealed shifts in sediment transport, with post-1990 SSL values surpassing pre-1990 levels at higher cumulative probabilities, suggesting altered sediment retention and release patterns. To improve SSL prediction, tree-based ML models were developed and evaluated using R2, RMSE, and MAE metrics. Among them, the extra trees regressor (ETR) demonstrated the highest predictive accuracy (R2 = 0.97 in training, 0.9 in testing) with the lowest errors, while the random forest regressor (RFR) and gradient boosting regressor (GBR) provided competitive results. The findings highlight the impact of human modifications on sediment transport and emphasize that ensemble tree-based models offer a robust solution for SSL prediction. This study provides valuable insights for river basin management and sustainable sediment transport modeling under changing hydrological conditions.

Radiological risks in Nasser lake water and their health and environmental implications

This study aimed to evaluate the activity concentrations of naturally occurring radionuclides (NORs) in Nasser Lake water, assess the associated radiological risks, and investigate the potential health and environmental impacts. The presence of these NORs is attributed to both natural geological formations, such as uranium-rich granitic and metamorphic rocks, and anthropogenic activities, including agricultural runoff. Water samples were analyzed for radium-226 (Ra-226), thorium-232 (Th-232), and potassium-40 (K-40). The Ra-226 concentration ranged from 0.08 ± 0.003 to 1.28 ± 0.06 becquerel per liter (Bq/l), mostly between 0.2 and 1.0 Bq/l, reflecting geological and anthropogenic influences. The symbol (±) represents the measurement uncertainty associated with gamma spectrometric analysis. According to international radiation safety guidelines, Ra-226 levels below 1 Bq/l are considered safe for consumption. The Th-232 concentration varied from 0.04 ± 0.001 to 0.96 ± 0.06 Bq/l, showing significant spatial variation. Similarly, K-40 concentrations ranged from 1.35 ± 0.11 to 16.57 ± 1.43 Bq/l, with some notably high values. The annual effective dose (Eff) ranged from 15.8 to 266.15 micro sievert per year (µSv/y) for adults, reaching 362.92 µSv/y for children and 221.54 µSv/y for infants. The doses for children and infants exceeded the recommended thresholds. Cancer risk (CR) assessments showed that men’s mortality risks ranged from 2.56 × 10−5 to 4.10 × 10−4, while women’s ranged from 2.68 × 10−5 to 4.29 × 10−4. Morbidity risks varied between 3.72 × 10−5 and 5.95 × 10−4 for men and 3.89 × 10−5 to 6.22 × 10−4 for women. These risks correlate with specific lake locations, highlighting hot spots with elevated radioactive content. Water acidity levels (pH) ranged from 6.23 to 7.9, indicating predominantly neutral to slightly alkaline conditions. These variations correlated with electrical conductivity (EC), reflecting complex interaction between pH, EC, and NORs. The study assesses gamma radiation hazards from external exposure and internal risks from alpha-emitting radionuclides, such as Ra-226 and Th-232, through water ingestion. While most samples comply with standard radiation limits, elevated radionuclide levels in certain areas pose potential health risks, particularly for vulnerable populations like children. Continuous monitoring of radiological parameters in Naser Lake is essential to trace long-term trends and ensure safety compliance. Additionally, advanced water treatment methods could help mitigate radionuclide concentrations in affected areas.

Flood fatalities and displacement influence human migration in floodplains of developing countries

Understanding what drives human migration in floodplains is critical for mitigating risks and enhancing resilience to floods. However, existing global analyses have not fully explored these complex dynamics. Here we introduce a metric, human-flood distance change, to track migration in floodplains from 2000 to 2018, exploring the interplay of climatic and anthropogenic influences. We find that in developing countries, including India, Argentina, Brazil and Nigeria, flood fatalities and displacement strongly influence migration decisions, often forcing populations to move away or toward flood-prone areas due to flood damage memory or resource needs. Conversely, regions with higher flood protection, such as the United States, show migration trends away from hazardous areas. Climatic drivers, like flood inundation area, exert stronger influences in Australia. Notably, in the Philippines and Kenya, the easing of drought-flood abrupt alternation has led to increased population movement toward flood-prone areas, underscoring the complex interactions between multiple hazards.