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دورة حياة الماء
يعد هذا الكتاب دورة حياة الماء وهو مخصص للأطفال يستهدف الطفولة المبكرة تعمل على استثمار الطفل في بناء المهارات المختلفة المرتبطة بالخيال والابتكار وقوة الشخصية والبحث عن حلول إبداعية ويستمد الطفل من خلالها الكثير من العلم والمعرفة والمعلومات ويعد من المنهج السلوكي التربوي رائع يعلم الطفل كيف يستخلص من مشكلاته وكيف يبني شخصيته بشكل مميز.
BOOK
Spatiotemporal variations of bacterial communities and functional genes in the water and sediments of a typical river influenced by reservoir operations
IntroductionMicroorganisms are essential for cycling phosphorus and nitrogen and play a crucial role in maintaining the health and stability of river ecosystems. The reservoir operation changes the river's hydrological processes, forming reservoir inundation areas and influencing the diversity of microorganisms and their environmental functions.MethodsTo study the microbial composition and action mechanism in rivers affected by reservoir operation, Xiangxi River, the closest tributary to the Three Gorges Dam on the Yangtze River, was sampled to examine the spatiotemporal fluctuations of bacterial populations and functional genes in water and sediments. The physicochemical properties, microbial communities and functional genes were analyzed in August 2022 and June 2023.ResultsSpatially, except for conductivity, the chlorophyll (Chl), dissolved oxygen (DO), and pH values in the upper reaches of the basin were higher than those in the mouth (where it joins the Yangtze River). Specific physicochemical gradients created by the reservoir operation drove spatial and temporal shifts in bacterial community structure. In water samples (W), dominant microbial species included Exiguobacterium and Candidatus Fonsibacter, contributing to organic matter degradation and nutrient transformation. Nitrospira indicated their roles as nitrifiers or denitrifiers in sediment samples (S), essential for nitrogen cycling. In the mouth zone, Methyloceanibacter dominated in the transition zone, and they were involved in methane or organic metabolism.DiscussionThe dominance of Microcystis in the upstream region reflected its prevalence in nutrient-rich, algal-rich environments. Paralia in the middle of the river highlighted the favorable conditions of suitable light and moderate flow rates for diatom growth. Reservoir regulation also altered the functional gene composition, making it more similar to that found in lake ecosystems. The most abundant functional genes were those associated with Amino Acid Transport and Metabolism, while phosphorus-related genes predominantly involved energy production and conversion. The dominance of genes linked to electron transport underscored the pivotal role of microbial respiration and oxidative phosphorylation in energy metabolism, which was fundamental to ecosystem productivity.
Journal Article
An intelligent SWMM calibration method and identification of urban runoff generation patterns
The accuracy of urban runoff simulation using the Storm Water Management Model (SWMM) largely depends on parameter calibration. This study proposes a universal and effective method to enhance model accuracy by optimizing parameter value ranges through an unsupervised intelligent clustering algorithm. Simulation scenarios with varying proportions of pervious and impervious areas are established, and sensitivity analysis is conducted to rank key parameters and identify dominant runoff generation patterns. The results show that when the impervious area is less than 10%, the most sensitive parameters are Zero.Imperv, N.Imperv, and Dstore-Imperv, indicating that runoff primarily originates from pervious surfaces. As the impervious area increases, runoff generation shifts to impervious areas, where the Unit Hydrograph Model, with fewer parameters and a simpler calibration process, leads to higher simulation accuracy. These findings improve the reliability of SWMM calibration and provide a reference for setting accuracy requirements under different urban surface conditions.
Journal Article
Analytical Model of Velocity Distribution and Penetration Characteristics in Water‐Level Fluctuation Zone With Vegetation
As a critical ecological transition zone between aquatic and terrestrial ecosystems, the water‐level fluctuation zone significantly influences flow structure through vegetation morphology. Conventional analytical velocity models inadequately address the variation in vegetation with water depth. In this study, we developed a hydrodynamic coupled model with vertically varying leaf vegetation widths and derived its analytical solutions. We have updated the dynamic invasion width formula in the context of studying vegetation‐flow interactions within water‐level fluctuation zones. This work quantitatively investigates flow interactions at the main channel‐floodplain interface, establishes a dynamic relationship between the resistance coefficient and vegetation geometric parameters, and proposes a modified Kármán coefficient expression incorporating free water layer corrections under submerged conditions. Experimental and numerical validation revealed the shear layer evolution mechanisms and turbulent kinetic energy redistribution patterns (vertical‐lateral) under semi‐vegetated conditions. This study overcomes the traditional assumption of vegetation homogeneity. The findings will provide a fundamental basis for research on dissolved oxygen variations and pollutant diffusion processes in the littoral zone under vegetation‐flow interactions. It also analyzes the vertical variations in vegetation morphology within water‐level fluctuation zones, and offering a high‐precision analytical tool for eco‐hydrological simulations under vertically graded vegetation configurations and associated hydrodynamic impacts in these zones.
Journal Article
Characterization and Environmental Risk Assessment of Coal-based Solid Waste Towards Underground Backfilling
This study evaluated the feasibility of coal-based solid waste as a subsurface fill material based on its physicochemical properties and potential environmental risks. The results show that the special physical structure and the chemical composition of coal-based solid wastes are advantageous as filling materials. In terms of physical structure, the spheres improve the flowability and mixing homogeneity of the mixture, while lumps give stabilizing support; the special chemical compositions also improve the strength, durability and corrosion resistance of the filler. The contents of Cd, As, Cr, Cu, Ni and Co in coal-based solid waste are less directly harmful to the environment, but arsenic showed a relatively strong enrichment. Cd in coal gangue and desulfurized gypsum were medium or very high risk due to strong migration and bioavailability, respectively, while Co in desulfurized gypsum present a medium risk. Both coal gangue and desulfurized gypsum may contaminate the underground environment, the other materials pose less threat to the environmental. In engineering applications, attention should be paid to the main contaminant As, as well as Cd and Co because of their mobility and high bioactive fraction, to reduce potential environmental risk.
Journal Article
Study on multi-scenario and multi-water source allocation in Henan water supply area of Yellow River considering extreme drought
The water supply of water resources allocation under extreme drought is insufficient, and the limited available water resources make it urgent to tap the potential of water supply. In this study, the Yellow River water supply area in Henan Province is taken as an example to study the multi-water source allocation under extreme drought. According to the Palmer Drought Severity Index (PDSI), the extreme drought years are selected, and the water supply and demand balance in the extreme drought years is analyzed, and the water shortage degree of each water supply area is obtained. In this study, unconventional water, flood resource utilization and elastic exploitation of groundwater are used as potential water sources. Different water supply scenarios are set up according to different potential tapping measures, and multi-scenario supply increase under extreme drought is explored. In the case of severe drought, the amount of potential tapping water has been significantly improved through different scenarios of potential tapping measures. The amount of potential tapping water in the three scenarios is 1.499 hundred million m 3 , 2.745 hundred million m 3 and 3.991 hundred million m 3 . Under different water supply scenarios, the total water shortage has been reduced from 4.555 hundred million m 3 to 3.054 hundred million m 3 , 1.808 hundred million m 3 and 0.562 hundred million m 3 , respectively. The total water shortage rate decreased from 31.07% to 20.83%, 12.33% and 3.83%, respectively. A multi-water source allocation model with the goal of minimizing water shortage is constructed, and a multi-scenario supply increase allocation scheme is proposed, which provides a basis for the study of water supply increase allocation to alleviate the drought degree of the Yellow River Water Supply Area in Henan. Through the Multi-scenario potential tapping of multiple water sources, the existing potential water volume can be maximized, which is conducive to reducing the water supply pressure and water use restrictions of conventional water sources, improving the support capacity and guarantee capacity of water resources, and reducing the economic and social development bottlenecks caused by extreme drought.
Journal Article
Evolution and attribution analysis of baseflow on both banks of the Wei River basin
Baseflow is a crucial component of river runoff and river ecological health. Reliable baseflow separation and attribution of its drivers are important for sustainable water management in arid and semi-arid basins. We analyzed 18 tributaries on the north and south banks of the Wei River basin (2006–2020). Nine baseflow separation methods were compared, and performance was evaluated using NSE and KGE. We then assessed trends of hydro-meteorological variables and quantified the contributions of climate change and human activities to baseflow changes. Among the nine methods, F2 performed best, with the highest mean NSE (0.73) and mean KGE (0.76) across the 18 sites. Baseflow on both banks showed a non-significant increasing trend (P > 0.05). Precipitation significantly affected baseflow on both banks, and potential evapotranspiration also had a significant influence on the south bank (P < 0.05). Attributions differed spatially: on the south bank, baseflow changes at Laoyukou, Dayu, and Luolicun were mainly climatedriven (63.26%, 58.81%, and 74.55%), while on the north bank only Fenggeling and Qianyang were mainly climate-driven (72.29% and 53.92%); most other stations were mainly influenced by human activities. The optimal separation method and the contrasting attributions between banks highlight strong spatial heterogeneity in baseflow controls and underscore the importance of considering both climatic drivers and human activities in basin management.
Journal Article
Remote sensing of the terrestrial water cycle
Remote Sensing of the Terrestrial Water Cycle is an outcome of the AGU Chapman Conference held in February 2012. This is a comprehensive volume that examines the use of available remote sensing satellite data as well as data from future missions that can be used to expand our knowledge in quantifying the spatial and temporal variations in the terrestrial water cycle. Volume highlights include: - An in-depth discussion of the global water cycle - Approaches to various problems in climate, weather, hydrology, and agriculture - Applications of satellite remote sensing in measuring precipitation, surface water, snow, soil moisture, groundwater, modeling, and data assimilation - A description of the use of satellite data for accurately estimating and monitoring the components of the hydrological cycle - Discussion of the measurement of multiple geophysical variables and properties over different landscapes on a temporal and a regional scale Remote Sensing of the Terrestrial Water Cycle is a valuable resource for students and research professionals in the hydrology, ecology, atmospheric sciences, geography, and geological sciences communities.
eBook
Performance evaluation of global hydrological models in six large Pan-Arctic watersheds
Global Water Models (GWMs), which include Global Hydrological, Land Surface, and Dynamic Global Vegetation Models, present valuable tools for quantifying climate change impacts on hydrological processes in the data scarce high latitudes. Here we performed a systematic model performance evaluation in six major Pan-Arctic watersheds for different hydrological indicators (monthly and seasonal discharge, extremes, trends (or lack of), and snow water equivalent (SWE)) via a novel Aggregated Performance Index (API) that is based on commonly used statistical evaluation metrics. The machine learning Boruta feature selection algorithm was used to evaluate the explanatory power of the API attributes. Our results show that the majority of the nine GWMs included in the study exhibit considerable difficulties in realistically representing Pan-Arctic hydrological processes. Average APIdischarge (monthly and seasonal discharge) over nine GWMs is > 50% only in the Kolyma basin (55%), as low as 30% in the Yukon basin and averaged over all watersheds APIdischarge is 43%. WATERGAP2 and MATSIRO present the highest (APIdischarge > 55%) while ORCHIDEE and JULES-W1 the lowest (APIdischarge ≤ 25%) performing GWMs over all watersheds. For the high and low flows, average APIextreme is 35% and 26%, respectively, and over six GWMs APISWE is 57%. The Boruta algorithm suggests that using different observation-based climate data sets does not influence the total score of the APIs in all watersheds. Ultimately, only satisfactory to good performing GWMs that effectively represent cold-region hydrological processes (including snow-related processes, permafrost) should be included in multi-model climate change impact assessments in Pan-Arctic watersheds.
Journal Article
GCIP, global energy and water cycle experiment (GEWEX), continental-scale international project
Efforts to understand climate variability and predict future climate change have highlighted many aspects of the hydrologic cycle and the exchange of energy and water at the atmosphere-surface interface as areas of critically needed study. The very nature of weather and climate demands that an international perspective and a comprehensive research approach be applied to understand these important issues.In response to this need, the international partners of the World Climate Research Program developed GEWEX (Global Energy and Water Experiment) as a major focus of international study. As the first of five continental-scale experiments, the GEWEX Continental Scale International Project (GCIP) was established to quantitatively assess the hydrologic cycle and energy fluxes of the Mississippi River basin.GCIP focuses on understanding the annual, interannual, and spatial variability of hydrology and climate within the Mississippi River basin; the development and evaluation of regional coupled hydrologic/atmospheric models; the development of data assimilation schemes; and the development of accessible, comprehensive databases. Improved water resource management on seasonal to interannual time scales is also a key GCIP goal. This book reviews the GCIP program, describes progress to date, and explores promising opportunities for future progress.
eBook