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The importance of climate in water resources management is well recognized, but less is known about how climate affects water access at the household level. Understanding this is crucial for identifying vulnerable households, reducing health and well-being risks, and finding equitable solutions. Using difference-in-differences regression analyses and relying on temporal variation in interview timing from multiple, cross-sectional surveys, we examine the effects of monsoon riverine flooding on household water access among 34 000 households in Bangladesh in 2011 and 2014. We compare water access, a combined measure of both water source and time for collection, among households living in flood-affected and non-flood-affected districts before and after monsoon flooding events. We find that households in monsoon flood-affected districts surveyed after the flooding had between 2.27 and 4.42 times higher odds of experiencing low water access. Separating geographically, we find that while households in coastal districts have lower water access than those in non-coastal districts, monsoon flood exposure is a stronger predictor of low water access in non-coastal districts. Non-coastal districts were particularly burdened in 2014, when households affected by monsoon flooding had 4.71 times higher odds of low water access. We also find that household wealth is a consistent predictor of household water access. Overall, our results show that monsoon flooding is associated with a higher prevalence of low water access; socioeconomically vulnerable households are especially burdened.
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This chapter of the New York City Panel on Climate Change 4 (NPCC4) report provides a comprehensive description of the different types of flood hazards (pluvial, fluvial, coastal, groundwater, and compound) facing New York City and provides climatological context that can be utilized, along with climate change projections, to support flood risk management (FRM). Previous NPCC reports documented coastal flood hazards and presented trends in historical and future precipitation and sea level but did not comprehensively assess all the city's flood hazards. Previous NPCC reports also discussed the implications of floods on infrastructure and the city's residents but did not review the impacts of flooding on the city's natural and nature-based systems (NNBSs). This-the NPCC's first report focused on all drivers of flooding-describes and profiles historical examples of each type of flood and summarizes previous and ongoing research regarding exposure, vulnerability, and risk management, including with NNBS and nonstructural measures.
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Extreme weather events, such as those associated with winds and precipitation, result in billions of euros in damages annually. While changes in extreme precipitation due to global warming have already been detected at sub-continental scales, their complex characteristics make them a challenges to asses at more regional scales. Extreme winds present an even greater challenge as the varying dynamical response to global warming exhibits high levels of uncertainty. This situation is complicated by local scale interactions with orography, cities, land-sea contrasts, etc. The dataset presented here attempts to address these challenges and provide information that will allow robust assessment of extreme winds and precipitation (maximum five day precipitation). We achieve this by leveraging a large ensemble (52 members) of high resolution (12 km) EURO-CORDEX simulations. The dataset will be of value, not only to the scientific community, but also practitioners in the public (e.g., municipal planners, government agencies) and private sectors (e.g., insurers and reinsurers).
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Human-induced disturbances such as dam construction and regulation have led to widespread alterations in hydrological processes and thus substantially influence plant characteristics in the hydro-fluctuation zones (HFZs). To reveal utilization of limited resources and mechanisms of inter-specific competition and species co-existence of plant communities based on niche breadth and overlap under the different HFZs of the Three Gorges Reservoir (TGR) in China, we conducted a field investigation with 368 quadrats on the effects of hydrological alterations on plant diversity and niche characteristics. The results showed anti-seasonal flooding precipitated the gradual disappearance of the original diverse niches, resulting in the reduction of plant species richness and functional diversity and more obvious competition among plant species with similar resource requirements. Annuals, perennials and shrubs accounted for 71.23%, 27.39% and 1.37%, respectively, suggesting that annuals and flood-tolerant riparian herbs were favored under such novel flooding conditions. A consistent increase in species number, Shannon-Wiener diversity index and Simpson dominance index with altitude was inconsistent with hump-shaped diversity-disturbance relationship of the intermediate disturbance hypothesis, while the opposite trend was observed for the Pielou evenness index. This species distribution pattern might be caused by several synergetic attributes (e.g., the submergence depth, plant tolerant capacity to flooding, life form, dispersal mode and inter-specific competition). Vegetation types shifted from xerophytes to mesophytes and eventually to hygrophytes with the increasing flooding time in the HFZs. Hydrological alterations proved to be the paramount driver of vegetation distribution in the different HFZs. The niche analysis provided the first insights on the mechanisms of resource utilization and inter-specific competition, of which annuals could germinate quickly after soil drainage to achieve the greatest competitive advantages and occupy a larger niche space than other plants. Vegetation was still in the early stage of primary succession in the novel riparian forests. Therefore, vegetation restoration strategies should be biased towards herbaceous plants, due to annuals with better environmental adaptability, supplemented by shrubs and small trees. To establish a complete reference system for vegetation restoration, natural vegetation monitory plots in the different succession stages should be established in the different HFZs of the TGR, and their environmental conditions, community structures and inter-specific relationships further analyzed.
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Flooding threatens crop productivity, agricultural sustainability, and global food security. In this article I review the effects of flooding on plants and highlight three important gaps in our understanding: (i) effects of flooding on ecological interactions mediated by plants both below (changing root metabolites and exudates) and aboveground (changing plant quality and metabolites, and weakening the plant immune system), (ii) flooding impacts on soil health and microorganisms that underpin plant and ecosystems health, and (iii) the legacy impacts of flooding. Failure to address these overlooked aspects could derail and undermine the monumental progress made in building climate-resilient crops and soil-microbe-assisted plant resilience. Addressing the outlined knowledge gaps will enhance solutions developed to mitigate flooding and preserve gains made to date.
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Agricultural environments are becoming increasingly contaminated with plastic pollution. Plastics in the environment can also provide a unique habitat for microbial biofilm, termed the 'plastisphere', which can also support the persistence of human pathogens such as Salmonella. Human enteric Salmonella enterica serovar Typhimurium can enter agricultural environments via flooding or from irrigation with contaminated water. Using soil mesocosms we quantified the ability of S. Typhimurium to persist on microplastic beads in two agriculturally relevant soils, under ambient and repeat flood scenarios. S. Typhimurium persisted in the plastisphere for 35 days in both podzol and loamy soils; while during multiple flood events was able to survive in the plastisphere for up to 21 days. S. Typhimurium could dissociate from the plastisphere during flooding events and migrate through soil in leachate, and importantly could colonise new plastic particles in the soil, suggesting that plastic pollution in agricultural soils can aid S. Typhimurium persistence and facilitate further dissemination within the environment. The potential for increased survival of enteric human pathogens in agricultural and food production environments due to plastic contamination poses a significant public health risk, particularly in potato or root vegetable systems where there is the potential for direct contact with crops.
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BACKGROUND AND AIMS: Roots and rhizomes are critical for the adaptation of clonal plants to soil water gradients. Oryza longistaminata, a rhizomatous wild rice, is of particular interest for perennial rice breeding due to its resilience under abiotic stress conditions. While root responses to soil flooding are well-studied, rhizome responses to water gradients remain underexplored. We hypothesize that physiological integration of Oryza longistaminata mitigates heterogeneous water deficit stress through interconnected rhizomes, and both roots and rhizomes respond to contrasting water conditions. METHODS: We investigated the physiological integration between mother plants and ramets, measuring key photosynthetic parameters (photosynthetic and transpiration rate, and stomatal conductance) using an Infrared Gas Analyzer. Moreover, root and rhizome responses to three water regimes (flooding, well-watered, and water deficit) were examined by measuring radial water loss and apparent permeance to O2, along with histochemical and anatomical characterization. KEY RESULTS: Our experiment highlights the role of physiological integration via interconnected rhizomes in mitigating water deficit stress. Severing rhizome connections from mother plants or ramets exposed to water deficit conditions led to significant decreases in key photosynthetic parameters, underscoring the importance of rhizome connections in bidirectional stress mitigation. Additionally, O. longistaminata rhizomes exhibited constitutive suberized and lignified apoplastic barriers, while such barriers were induced in roots under water stress. Anatomically, both rhizomes and roots respond similarly to water gradients, showing thinner diameters under water deficit conditions and larger diameters under flooding conditions. CONCLUSION: Our findings indicate that physiological integration through interconnected rhizomes helps alleviate water deficit stress when either the mother plant or the ramet is experiencing water deficit, while the counterpart is in control conditions. Moreover, O. longistaminata can adapt to various soil water regimes by regulating anatomical and physiological traits of roots and rhizomes.
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BACKGROUND: Climate change induces perturbation in the global water cycle, profoundly impacting water availability for agriculture and therefore global food security. Water stress encompasses both drought (i.e. water scarcity) that causes the drying of soil and subsequent plant desiccation, and flooding, which results in excess soil water and hypoxia for plant roots. Terrestrial plants have evolved diverse mechanisms to cope with soil water stress, with the root system serving as the first line of defense. The responses of roots to water stress can involve both structural and physiological changes, and their plasticity is a vital feature of these adaptations. Genetic methodologies have been extensively employed to identify numerous genetic loci linked to water stress-responsive root traits. This knowledge is immensely important for developing crops with optimal root systems that enhance yield and guarantee food security under water stress conditions. RESULTS: This review focused on the latest insights into modifications in the root system architecture and anatomical features of legume roots in response to drought and flooding stresses. Special attention was given to recent breakthroughs in understanding the genetic underpinnings of legume root development under water stress. The review also described various root phenotyping techniques and examples of their applications in different legume species. Finally, the prevailing challenges and prospective research avenues in this dynamic field as well as the potential for using root system architecture as a breeding target are discussed. CONCLUSIONS: This review integrated the latest knowledge of the genetic components governing the adaptability of legume roots to water stress, providing a reference for using root traits as the new crop breeding targets.
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Mapeo Cromosómico , Deshidratación , Fabaceae , Fenotipo , Raíces de Plantas , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/fisiología , Fabaceae/genética , Fabaceae/fisiología , Adaptación Fisiológica/genética , Sequías , Inundaciones , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/fisiologíaRESUMEN
Advances in connectivity, communication, computation, and algorithms are driving a revolution that will bring economic and social benefits through smart technologies of the Industry 4.0 era. At the same time, attackers are targeting this expanded cyberspace to exploit it. Therefore, many cyberattacks are reported each year at an increasing rate. Traditional security devices such as firewalls, intrusion detection systems (IDSs), intrusion prevention systems (IPSs), anti-viruses, and the like, often cannot detect sophisticated cyberattacks. The security information and event management (SIEM) system has proven to be a very effective security tool for detecting and mitigating such cyberattacks. A SIEM system provides a holistic view of the security status of a corporate network by analyzing log data from various network devices. The correlation engine is the most important module of the SIEM system. In this study, we propose the optimized correlator (OC), a novel correlation engine that replaces the traditional regex matching sub-module with a novel high-performance multiple regex matching library called "Hyperscan" for parallel log data scanning to improve the performance of the SIEM system. Log files of 102 MB, 256 MB, 512 MB, and 1024 MB, generated from log data received from various devices in the network, are input into the OC and simple event correlator (SEC) for applying correlation rules. The results indicate that OC is 21 times faster than SEC in real-time response and 2.5 times more efficient in execution time. Furthermore, OC can detect multi-layered attacks successfully.
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This paper introduces a novel stability metric specifically developed for IQRF wireless mesh sensor networks, emphasizing flooding routing and data collection methodologies, particularly IQRF's Fast Response Command (FRC) technique. A key feature of this metric is its ability to ensure network resilience against disruptions by effectively utilizing redundant paths in the network. This makes the metric an indispensable tool for field engineers in both the design and deployment of wireless sensor networks. Our findings provide valuable insights, demonstrating the metric's efficacy in achieving robust and reliable network operations, especially in data collection tasks. The inclusion of redundant paths as a factor in the stability metric significantly enhances its practicality and relevance. Furthermore, this research offers practical ideas for enhancing the design and management of wireless mesh sensor networks. The stability metric uniquely assesses the resilience of data collection activities within these networks, with a focus on the benefits of redundant paths, underscoring the significance of stability in network evaluation.
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Purpose: To explore the relationship between post-traumatic stress disorder (PTSD) and students' academic control and academic emotion in the aftermath of a flood disaster. The findings will offer educators and relevant departments valuable insights to understand and facilitate the restoration of learning capabilities among students affected by the disaster. Methods: This study employed a combined approach of questionnaire surveys and longitudinal tracking. Students from Guangling Primary and Secondary School (Shouguang City, Weifang, Shandong Province) participated in surveys administered in September 2018, December 2018, and September 2019. The instruments utilized included the Post-Disaster Trauma Assessment Questionnaire, the Adolescent Academic Control Scale, and the mathematical version of the Achievement Emotions Questionnaire. Data analysis involved two-factor correlation and mediation effect testing. Results: Significant differences were observed in overall PTSD scores and its three dimensions between the 1-week and 1-year post-disaster assessments. Both the average PTSD score and the detection rate were higher 1 year after the disaster compared to the first week. Students' academic control demonstrated a strong positive correlation with positive academic emotions and a significant negative correlation with anxiety-related academic emotions. Cross-lagged regression analysis indicated a predictive relationship: academic control measured 3 months post-disaster significantly predicted academic emotions at the 9-month assessment, and conversely, academic emotions at the 3-month point were predictive of academic control at 9 months. In addition, academic control appears to play a complete mediating role in the relationship between PTSD and academic emotions. Conclusion: Students exhibited a range of PTSD symptoms following the disaster, with a higher prevalence noted in the first year compared to the initial week. PTSD negatively affects academic standing in these students, and is predictive of both their sense of academic control and their emotional responses to learning. Crucially, academic control and academic emotions exhibit a strong correlation and can mutually affect one another. Interventions aimed at reducing PTSD symptoms, cultivating positive academic emotions, and strengthening students' sense of academic control must therefore consider the relationship between these factors. This holistic approach will enhance psychological well-being and improve academic performance.
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Both seed germination and subsequent seedling establishment are key checkpoints during the life cycle of seed plants, yet flooding stress markedly inhibits both processes, leading to economic losses from agricultural production. Here, we report that melatonin (MT) seed priming treatment enhances the performance of seeds from several crops, including soybean, wheat, maize, and alfalfa, under flooding stress. Transcriptome analysis revealed that MT priming promotes seed germination and seedling establishment associated with changes in abscisic acid (ABA), gibberellin (GA), and reactive oxygen species (ROS) biosynthesis and signaling pathways. Real-time quantitative RT-PCR (qRT-PCR) analysis confirmed that MT priming increases the expression levels of GA biosynthesis genes, ABA catabolism genes, and ROS biosynthesis genes while decreasing the expression of positive ABA regulatory genes. Further, measurements of ABA and GA concentrations are consistent with these trends. Following MT priming, quantification of ROS metabolism-related enzyme activities and the concentrations of H2O2 and superoxide anions (O2 -) after MT priming were consistent with the results of transcriptome analysis and qRT-PCR. Finally, exogenous application of GA, fluridone (an ABA biosynthesis inhibitor), or H2O2 partially rescued the poor germination of non-primed seeds under flooding stress. Collectively, this study uncovers the application and molecular mechanisms underlying MT priming in modulating crop seed vigor under flooding stress.
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Ácido Abscísico , Inundaciones , Germinación , Giberelinas , Melatonina , Especies Reactivas de Oxígeno , Plantones , Semillas , Melatonina/farmacología , Melatonina/metabolismo , Germinación/efectos de los fármacos , Ácido Abscísico/metabolismo , Giberelinas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Plantones/metabolismo , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/genética , Semillas/efectos de los fármacos , Semillas/metabolismo , Semillas/crecimiento & desarrollo , Semillas/genética , Estrés Fisiológico , Productos Agrícolas/metabolismo , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacosRESUMEN
As urbanization continues to accelerate worldwide, urban flooding is becoming increasingly destructive, making it important to improve emergency scheduling capabilities. Compared to other scheduling problems, the urban flood emergency rescue scheduling problem is more complicated. Considering the impact of a disaster on the road network passability, a single type of vehicle cannot complete all rescue tasks. A reasonable combination of multiple vehicle types for cooperative rescue can improve the efficiency of rescue tasks. This study focuses on the urban flood emergency rescue scheduling problem considering the actual road network inundation situation. First, the progress and shortcomings of related research are analyzed. Then, a four-level emergency transportation network based on the collaborative water-ground multimodal transport transshipment mode is established. It is shown that the transshipment points have random locations and quantities according to the actual inundation situation. Subsequently, an interactive model based on hierarchical optimization is constructed considering the travel length, travel time, and waiting time as hierarchical optimization objectives. Next, an improved A* algorithm based on the quantity of specific extension nodes is proposed, and a scheduling scheme decision-making algorithm is proposed based on the improved A* and greedy algorithms. Finally, the proposed decision-making algorithm is applied in a practical example for solving and comparative analysis, and the results show that the improved A* algorithm is faster and more accurate. The results also verify the effectiveness of the scheduling model and decision-making algorithm. Finally, a scheduling scheme with the shortest travel time for the proposed emergency scheduling problem is obtained.
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A carbon paper-based gas diffusion electrode (GDE) is used with a bismuth(III) subcarbonate active catalyst phase for the electrochemical reduction of CO2 in a gas/electrolyte flow-by configuration electrolyser at high current density. It is demonstrated that in this configuration, the gas and catholyte phases recombine to form K2CO3/KHCO3 precipitates to an extent that after electrolyses, vast amount of K+ ions is found by EDX mapping in the entire GDE structure. The fact that the entirety of the GDE gets wetted during electrolysis should, however, not be interpreted as a sign of flooding of the catalyst layer, since electrolyte perspiring through the GDE can largely be removed with the outflow gas, and the efficiency of electrolysis (toward the selective production of formate) can thus be maintained high for several hours. For a full spatial scale quantitative monitoring of electrolyte penetration into the GDE, (relying on K+ ions as tracer) the method of inductively coupled plasma-mass spectrometry (ICP-MS) assisted energy dispersive X-ray (EDX) tomography is introduced. This new, cheap and robust tomography of non-uniform aspect ratio has a large planar span that comprises the entire GDE surface area and a submicrometer depth resolution, hence it can provide quantitative information about the amount and distribution of K+ remnants inside the GDE structure, in three dimensions.
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Low-Salinity Water Flooding (LSWF) is a technique aimed at modifying the interactions between rock and fluids particularly altering wettability and reducing interfacial tension (IFT). However, there remains limited understanding of how heterogeneous wettability and the presence of Initial Water Saturation (Swi) can impact the effectiveness of LSWF. This study contributes to a deeper understanding of LSWF mechanisms in the context of heterogeneous wettability, while also considering Swi. The simulations were conducted using OpenFOAM, employing a non-reactive quasi-three-phase flow solver that accounts for wettability alteration and IFT reduction during the mixing of Low-Salinity (LSW) and High-Salinity Water (HSW). A heterogeneous pore geometry is designed, and four distinct scenarios are simulated, encompassing both heterogeneous and homogeneous wettability conditions while considering the presence of Swi. These scenarios included secondary High-Salinity Water Flooding (HSWF), tertiary and secondary LSWF. Notably, the simulations reveal that secondary LSWF consistently yields the highest oil recovery across all scenarios, achieving recovery rates of up to 96.98 %. Furthermore, the presence of Swi significantly influences the performance of LSWF in terms of oil recovery, particularly in heterogeneous wettability conditions where it boosts recovery by up to 3.5 %, but in homogeneous wettability, it decreases recovery by nearly 26 %. These simulations also underscore the pivotal role played by the distribution of oil and HSW phases in profoundly affecting the outcomes of LSWF.
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Polymer flooding is an effective development technology to enhance oil recovery, and it has been widely used all over the world. However, after long-term polymer flooding, a large number of oilfields have experienced a sharp decline in reservoir development efficiency. High water cut wells, serious dispersion of residual oil distribution and complex reservoir conditions all bring great challenges to enhance oil recovery. In this study, the method of enhancing oil recovery after polymer flooding was studied by taking the S Oilfield as an example. A surfactant-polymer system suitable for high-permeability heterogeneous oilfields was developed, comprising biogenic surfactants and polymers. Microscopic displacement experiments were conducted using cast thin sections from the S Oilfield, and nuclear magnetic resonance was employed for core displacement experiments. Numerical simulation experiments were also conducted on the S Oilfield. The results show that the enhanced oil recovery mechanism of the surfactant-polymer system is to adjust the flow direction, expand the swept volume, emulsify crude oil and reduce interfacial tension. Surfactant-polymer flooding proves to be effective in improving recovery efficiency, significantly reducing the time of flooding and further enhancing the strong swept area. The nuclear magnetic resonance results indicate a high amplitude of passive utilization of residual oil during the surfactant-polymer flooding stage, highlighting the enormous potential for an increased recovery ratio. Surfactant-polymer flooding emerges as a more suitable technique to enhance oil recovery in the post polymer-flooding stage in high-permeability heterogeneous oilfields.
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Flooding is a critical factor that limits the establishment of a symbiosis between rice and arbuscular mycorrhizal fungi (AMF) in wetland ecosystems. The distribution of carbon resources in roots and the acclimation strategies of rice to flooding stress in the presence of AMF are poorly understood. We conducted a root box experiment, employing nylon sheets or nylon meshes to create separate fungal chambers that either prevented or allowed the roots and any molecules to pass through. We found that the mycorrhizal colonization rate and the expression of genes OsD14L and OsCERK1, which are involved in fungal perception during symbiosis, both increased in mycorrhizal rice roots following intermittent flooding compared to continuous flooding. Furthermore, AMF inoculation affected root morphological traits, facilitating both shallower and deeper soil exploration. Increased submergence intensity led to carbohydrate deprivation in roots, while high mycorrhizal colonization increased soil oxygen consumption and decreased the neutral lipid concentration in roots. However, mycorrhizal inoculation increased the rice photosynthesis rate and facilitated acclimation to submergence by mediating the expression of the genes OsCIPK15 and OsSUB1A to enhance rice shoot elongation and the sugar concentration in roots as a result of reduced competition for carbon between rice and AMF under different flooding conditions.
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Predation is an important factor limiting bird populations and is usually the main factor influencing nest survival. In riverine habitats, flooding poses an additional significant challenge. Our study aimed to elucidate the influence of nest location and incubation timing on the survival of common sandpiper nests in a large, semi-natural, lowland river. The survey was carried out in central Poland on the Vistula River, in 2014-2015, 2021, and 2023, along two river sections 2 km and 10 km in length. The nest survival rate was 27%, which is twice as low as that reported on small upland rivers, with flooding being an additional factor causing losses on the Vistula River. Our research showed that mammalian and avian predation accounted for 51% of losses and flooding for 49% of losses. The negative impact of floods on nest survival decreased as the breeding season progressed between May and July, while the chances of being depredated increased during the same period. Nests placed under shrubs were less likely predated than nests located in grass. Moreover, locating the nest in proximity to water increased nesting survival and in fact, more nests found in our study were situated close to the water's edge.
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BACKGROUND: Oncomelania hupensis is the exclusive intermediate host of Schistosoma japonicum in China. Snail control is an essential component of schistosomiasis elimination programme. With 70 years of continuous efforts, the range of O. hupensis had reduced significantly, but slowed down in last decades. A large number of levees against flooding were constructed along Yangtze River and its affiliated lakes in the middle and lower reaches, which influenced the hydrology and ecology in the alluvial plains. The purpose of this study was to assess the impact of levees on the distribution of O. hupensis in the middle and lower reaches of the Yangtze River. METHODS: The snail habitats were digitalised by hand-held GPS system. The years for discovery and elimination of snail habitats were extracted from historical records. The accumulated snail-infested range for each habitat was calculated on the basis of annual reports. The current distribution of O. hupensis was determined by systematic and environmental sampling. The geographical distribution of levees was obtained from satellite imagery. To assess the impact of levees, the data pertaining to O. hupensis were divided into two parts: inside and outside the Yangtze River. Joinpoint regression was utilised to divide the study time span and further characterise the regression in each period. The 5-year-period moving averages of eliminated area infested by snails were calculated for the habitats inside and outside Yangtze River. The moving routes of corresponding geographical median centres were simulated in ArcGIS. Hotspot analysis was used to determine the areas with statistical significance clustering of O. hupensis density. RESULTS: Three periods were identified according to Joinpoint regression both inside and outside Yangtze River. The area infested by O. hupensis increased in the first two periods. It decreased rapidly outside Yangtze River year over year after 1970, while that inside the Yangtze River did not change significantly. Furthermore, the latter was significantly higher than the former. It was observed that the present density of O. hupensis inside Yangtze River was lower than outside the Yangtze River. The median centre for eliminated ranges inside Yangtze River wavered between the east (lower reach) and the west (middle reach). In contrast, the median centre for eliminated ranges continuously moved from the east to the west. CONCLUSIONS: Our findings indicated that the levees had a considerable negative impact on the distribution of O. hupensis outside Yangtze River. Some hotspots observed in the irrigation areas need a sluice system at the inlet of branch for snail control. The major distribution of O. hupensis located in Hubei might be caused by severe waterlogging. The intensive surveillance should be implemented there. The biggest two freshwater lakes, the major endemic regions historically, were identified as cold spots. The long-term impact of Three Gorges Dam on the distribution of O. hupensis in the lakes should be monitored and evaluated.
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Ecosistema , Ríos , Schistosoma japonicum , Caracoles , Animales , Caracoles/parasitología , Ríos/parasitología , China , Schistosoma japonicum/fisiología , Esquistosomiasis Japónica/transmisión , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/parasitologíaRESUMEN
The distribution coefficient (Kd) of radionuclides is a crucial parameter in assessing the safety of high-level radioactive waste (HLW) geological repository. It is determined in the laboratory through batch and column experiments. However, differences in obtained Kd values from distinct experiments have not been thoroughly assessed and compared. This study evaluated strontium (Sr) sorption on different granite materials using static batch and dynamic experiments (column and core-flooding experiments). The results from batch sorption experiments showed higher Sr sorption on granite under acidic and strongly alkaline conditions, low solid-liquid ratios, and low ionic strength. In column experiments, a two-site sorption model was used to simulate Sr transport in crushed granite and mixed pure minerals. The sorption of Sr on crushed granite exhibited a higher affinity than that of mixed pure minerals. The dual-porosity transport model was employed to investigate Sr transport behavior in fractured granite in the core-flooding experiment. Kd obtained from batch sorption experiments are four to twenty times higher than those from column experiments, and two to three orders of magnitude higher than that from a core-flooding experiment. The results of this study provide valuable insights into safety assessment for the HLW geological repository.