Large Reservoir Research Articles

Review of the development of requirements to ensure the safe operation of inland waterway vessels

The article reviews the development of requirements for vessels operating on inland waterways. The key points in the formation of the regulatory framework of the Russian Classification Society in terms of ensuring the safe operation of river vessels, taking into account the specifics of external loads on the hull of the vessel, are considered. The methods and approaches that became the basis of the existing Rules were formed in the 60-70s of the 20th century after the appearance of water reservoirs, the conditions of navigation in which differed significantly from river navigation. The next stage of development was the appearance of mixed (river-sea) navigation vessels based on river vessels operating in large lakes and reservoirs of inland waterways. By the end of the 1970s, mixed navigation vessels became a separate group, for which the requirements of normative documents for the safety of operation differed significantly from those for river vessels. First of all, this concerned the seaworthiness characteristics (stability, strength, freeboard) of the vessel's hull and its equipment, supplies, and devices. At the beginning of the 21st century, a study was carried out on the possibility of operating inland navigation vessels in coastal sea areas and in wind-wave protected areas with a maritime regime of navigation. The results have been applied in the Russian Classification Society's Regulations for roadstead and harbor navigation vessels (Guideline R.015-2006). The article analyses and confirms the necessity to develop a similar algorithm allowing assigning permissible operational restrictions for vessels whose class is lower than the basin class. The conditions for ensuring the safety of vessel operation should be assigned based on adjusted approaches that take into account the specifics of forecasting wind-wave parameters of water areas on inland waterways.

A Review of the Effects of Limnoperna fortunei (Dunker, 1857): Invasion on Hydraulic Structures and Ecosystems and Their Control

We review the research on L. fortunei over the past 22 years, systematically elucidating its impacts on ecological environments and water engineering structures. We explored the effects of external factors on the invasion and spread of L. fortunei, as well as the internal factors that impact the ecological environment and water engineering structures. We also provide new perspectives and directions for L. fortunei control. The major research findings include the following: (1) L. fortunei negatively impacts hydraulic structures, being hard to remove and capable of damaging them, disrupting normal operations. (2) L. fortunei’s ecological impact is multifaceted: it reduces water cloudiness and organic matter by filtering suspended particles and depositing feces, but its decay after death consumes dissolved oxygen, increasing chemical oxygen demand and lowering water quality. (3) L. fortunei control techniques are effective for localized use in small bodies of water and aqueducts, but their control in large open reservoirs is difficult to achieve with one method. Existing control methodologies for L. fortunei were systematically evaluated across multiple dimensions, including engineering applicability and feasibility, technical advantages and limitations, and economic cost-effectiveness. This comprehensive analysis establishes a decision-support framework for optimizing control strategy selection in diverse engineering scenarios and application contexts.

Regulatory Impacts of the Three Gorges Dam on Long-Term Terrestrial Water Storage Anomalies in the Three Gorges Reservoir Area: Insights from GRACE and Multi-Source Data

Understanding the impact of human activities on regional water resources is essential for sustainable basin management. This study examines long-term terrestrial water storage anomalies (TWSA) in the Three Gorges Reservoir Area (TGRA) over two decades, from 2003 to 2023. The analysis utilizes data from the Gravity Recovery and Climate Experiment (GRACE) and its successor mission (GRACE-FO), complemented by Global Land Data Assimilation System (GLDAS) models and ECMWF Reanalysis v5 (ERA5) datasets. The research methodically explores the comparative contributions of natural factors and human activities to the region’s hydrological dynamics. By integrating the GRACE Drought Severity Index (GRACE-DSI), this study uncovers the dynamics of droughts during extreme climate events. It also reveals the pivotal role of the Three Gorges Dam (TGD) in mitigating these events and managing regional water resources. Our findings indicate a notable upward trend in TWSA within the TGRA, with an annual increase of 0.93 cm/year. This trend is largely due to the effective regulatory operations of TGD. The dam effectively balances the seasonal distribution of water storage between summer and winter and substantially reduces the adverse effects of extreme droughts on regional water resources. Further, the GRACE-DSI analysis underscores the swift recovery of TWSA following the 2022 drought, highlighting TGD’s critical role in responding to extreme climatic conditions. Through correlation analysis, it was found that compared with natural factors (correlation 0.62), human activities (correlation 0.91) exhibit a higher relative contribution to TWSA variability. The human-induced contributions were derived from the difference between GRACE and GLDAS datasets, capturing the combined effects of all human activities, including the operations of the TGD, agricultural irrigation, and urbanization. However, the TGD serves as a key regulatory facility that significantly influences regional water resource dynamics, particularly in mitigating extreme climatic events. This study provides a scientific basis for water resource management in the TGRA and similar large reservoir regions, emphasizing the necessity of integrating the interactions between human activities and natural factors in basin management strategies.

Calibrating Streamflow and Hydrological Processes in Geological Regions Using a Combined Soft and Hard Calibration Approach

ABSTRACTConventional catchment‐scale models are often calibrated using a single set of parameters and considering only statistical performance, overlooking hydrological aspects of great relevance for a realistic modeling outcome. The main objectives of this study were to set up a hydrological model in the Tagus River headwaters (Spain) with the new version of the soil and water assessment tool and to develop a novel calibration and evaluation procedure to simulate the hydrological processes realistically, particularly focusing on groundwater contribution. The model was parameterized at three geological regions, and its performance was evaluated in representative sub‐catchments, addressing both soft and hard calibration to focus not only on daily streamflow but also on two hydrological indices: the runoff coefficient and the groundwater contribution. Results were then evaluated at the reservoir catchment level (two large reservoirs constitute the catchment outlet) and further validated on reservoir inflows. After this innovative procedure that incorporates a zonal calibration and a comprehensive model evaluation, a very good statistical performance was obtained, with NSE, R2, and PBIAS values (monthly) of 0.86, 0.88, and 2.5% for the Entrepeñas Reservoir inflows, and of 0.89, 0.91, and −8.5% for Buendía Reservoir. This performance was achieved while maintaining realistic values for the hydrological indices, providing a robust representation of the hydrological processes.

Periodic flooding alters ecological processes and carbon metabolism efficiency of riparian soil microbial communities in the three Gorges Reservoir area, China.

Periodic flooding alters ecological processes and carbon metabolism efficiency of riparian soil microbial communities in the three Gorges Reservoir area, China.

Identifying large vulnerable water reservoirs using passive seismic monitoring

Identifying large vulnerable water reservoirs using passive seismic monitoring

Large Molecular and Dust Reservoir of a Gravitationally Lensed Submillimeter Galaxy behind the Lupus I Molecular Cloud

Large Molecular and Dust Reservoir of a Gravitationally Lensed Submillimeter Galaxy behind the Lupus I Molecular Cloud

Formation of Iron-Helium Compounds under High Pressure.

We report the formation of fcc and distorted hcp iron-helium compounds with x in FeHe_{x} up to 0.13 and 0.48, respectively, based on experiments at 5-54GPa and ∼1000-2820 K. Upon releasing pressure under room temperature, these fcc and distorted hcp FeHe_{x} were still observed by XRD and SIMS measurements. Our first-principles calculations indicate that fcc and hcp FeHe_{x}, with helium atoms occupying the tetrahedral and trigonal-planar interstitial sites (instead of the octahedral sites), are dynamically stable throughout 0-50GPa. These results support that the Earth's core can be a large reservoir of primordial ^{3}He.

Water: The Essential Component of Our Inner Solar System

If our solar system started with the terrestrial planets initially covered with water, then a reasonable progression of events result in the presently observed inner solar system. Two principal assumptions have been made. One is that molten rock and the iron rich cores of the terrestrial planets can dissolve appreciable quantities of water. The other is that our solar system was formed initially from cold gas and dust which contained due to condensation large quantities of water. Water then became trapped in the cores and molten rock of the forming terrestrial planets. This in essence implies that our star formed as a lone star since if more than one star was involved it is unlikely that the gas and dust could be cold as to condense large quantities of water. Phase transitions involving water and carbon dioxide play a crucial role in the transition from this initial water covered state to what is observed today. Of the four terrestrial planets of our solar system Earth is the only one that developed mechanisms that allowed liquid water to be retained. Thus, Earth is the only terrestrial planet in our solar system that has the possibility for billion-year stability to allow evolution to work over a sufficiently long time for the evolution of intelligent life. The principal reasons for this are the presence of a magnetic field and plate tectonics that allow long term planet surface stability. The progression from an earlier state to what we see today was largely completed about 2 billion years ago so long term evolutionary development where possible should have proceeded. Mars is believed to have had surface water in this early stage but lost that as did Mercury and Venus. Volume changes upon the phase changes of water and carbon dioxide play a crucial role in driving the geology of Mars. The sublimation of carbon dioxide from solid to gas phase must play a crucial role in creating caverns and crevices below the surface if lifeforms are to exist on Mars. Simple lifeforms are then expected to exist below the surface of Mars. Recent seismic measurements indicate that both Earth and Mars possess large reservoirs of water well below the surfaces of each planet.

Anomalous δ15N values in the Neoarchean associated with an abundant supply of hydrothermal ammonium

Unusually high δ15N values in the Neoarchean sedimentary record in the time period from 2.8 to 2.6 Ga, termed the Nitrogen Isotope Event (NIE), might be explained by aerobic N cycling prior to the Great Oxidation Event (GOE). Here we report strongly positive δ15N values up to +42.5 ‰ in ~2.75 – 2.73 Ga shallow-marine carbonates from Zimbabwe. As the corresponding deeper-marine shales exhibit negative δ15N values that are explained by partial biological uptake from a large ammonium reservoir, we interpret our data to have resulted from hydrothermal upwelling of 15N-rich ammonium into shallow, partially oxic waters, consistent with uranium isotope variations. This work shows that anomalous N isotope signatures at the onset of the NIE temporally correlate with extensive volcanic and hydrothermal activity both locally and globally, which may have stimulated primary production and spurred biological innovation in the lead-up to the GOE.

Trophic niche interactions among native and non-native fish species vary spatially in one of the world's largest reservoirs

Trophic niche interactions among native and non-native fish species vary spatially in one of the world's largest reservoirs

Can large animals direct the fate of the vast arctic soil carbon reserves – a review

Abstract Arctic areas store vast soil carbon reserves that are highly sensitive to be released into the atmosphere due to a warming climate. Large arctic herbivores may shape this sensitivity, but owing to high spatial and temporal variation in their ecosystem effects, the conditions under which herbivores might negate soil carbon losses have remained elusive. Here, we summarize the main pathways by which ungulates may counteract unwanted climatic feedbacks of the ongoing warming. Firstly, they may counteract the climate-induced shrubification; secondly, induce ecosystem state transitions from shrub and moss dominance to grass and forb dominance; and thirdly, contribute to colder winter soil temperatures. In non-permafrost soils, these pathways feed back on climate mostly via herbivory-induced increases in albedo and, potentially, decreased sensitivity to wildfire-induced soil carbon losses. In permafrost soils, herbivores may additionally enhance soil carbon storage as the colder winter soil temperatures induced by vegetation change and trampling-associated compaction of snow may prevent permafrost melting under warming. The role of current large animal populations in the first pathway (i.e., counteracted shrubification) is already documented in many parts of the Arctic. Yet, the second and third pathway (i.e., ecosystem state transitions and snow-mediated permafrost feedbacks have only limited occurrence today and would require drastic increases in the number and diversity of herbivores to change arctic climate feedbacks at a larger scale, imposing a high degree of uncertainty on the feasibility of such efforts. Given the alarming trends the arctic carbon stocks are facing, a better understanding of the contribution of large herbivores to the carbon cycle is more urgent than ever before. This information would not only be relevant if introducing animal populations into areas with large carbon reservoirs, but also support the survival of current animal populations that already counteract shrubification and the warming-induced increase in albedo in many areas.

Exploratory Analysis on the Chemical Composition of Aquatic Macrophytes in a Water Reservoir—Rio de Janeiro, Brazil

This study explores the chemical composition of different macrophyte species and infers their potential in extracting nutrients and some heavy metals from water as well as the use of macrophytes’ biomass as natural fertilizers. It used a dataset obtained from a previous study composed of 445 samples of chemical concentrations in the dried biomass of 16 macrophyte species collected from the Santana Reservoir in Rio de Janeiro, Brazil. Correlation tests, analysis of variance, and factor analysis of mixed data were performed to infer correspondences between the macrophyte species. The results showed that the macrophyte species can be grouped into three different clusters with significantly different profiles of chemical element concentrations (N, P, K+, Ca2+, Mg2+, S, B, Cu2+, Fe2+, Mn2+, Zn2+, Cr3+, Cd2+, Ni2+, Pb2+) in their biomass (factorial map from PCA). Most marginal macrophytes have a lower concentration of chemical elements (ANOVA p-value < 0.05). Submerged and floating macrophyte species presented a higher concentration of metallic and non-metallic chemical elements in their biomass (ANOVA p-value < 0.05), revealing their potential in phytoremediation and the removal of toxic compounds (such as heavy metal molecules) from water. A cluster of macrophyte species also exhibited high concentrations of macronutrients and micronutrients (ANOVA p-value < 0.05), indicating their potential for use as soil fertilizers. These results reveal that the plant’s location in the reservoir (marginal, floating, or submerged) is a relevant feature associated with macrophytes’ ability to remove chemical components from the water. The obtained results can contribute to planning the management of macrophyte species in large water reservoirs.

Clinical and epidemiological features of the 2019 West Nile Fever outbreak in the city of Krasnodar: an observational study

For the Krasnodar Territory, West Nile fever (WNF) is an emergent infection with insufficiently studied clinical and epidemiological manifestations. The question of the role of the urban environment in the formation of new endemic foci remains open. Objective of the study: to characterize the main clinical and epidemiological manifestations of WNF and to determine the possible location of foci in the city of Krasnodar using the example of the 2019 outbreak. Methods. A retrospective analysis of 78 inpatient observation cards for WNF confirmed by ELISA and PCR in 2019 was conducted. The selection condition was the presence of patients within the city of Krasnodar and its suburbs within a month before the onset of the disease. Using the electronic resource "Yandex maps", data on the actual place of residence of patients is reflected, a map is built to determine possible epidemic foci in the city of Krasnodar and adjacent areas. Results. The outbreak of WNV in Krasnodar in July - September 2019, with a peak in August, was associated with the presence of large reservoirs and small water bodies inside the city. In the structure of clinical forms, meningeal and meningoencephalic (77.4%) prevailed (group 1), the influenza-like form was noted in 25.6% (group 2). There were no gender differences, the average age was 44.7 ± 0.51 years, 65% belonged to the unemployed group and pensioners. Comorbid pathology was present in 84.5% of patients in the 1st group and 35.0% in the 2nd, pathology of the cardiovascular system prevailed (46.1%). Typically, an acute onset with febrile fever, general cerebral and meningeal symptoms; development of meningitis with moderate lymphocytic pleocytosis. In the flu-like form, subfebrile fever was observed in 50% of cases, with exanthema (65%), lymphadenopathy (40%), hyperemia and granularity of the oropharyngeal mucosa (75-50%), and cough (30%) being the most common. Conclusion. Mapping the probable points of human infection confirmed the importance of intra-urban water bodies and helped to identify risk zones for infection transmission. Effective prevention of WNV in cities requires a set of surveillance measures for water bodies within populated areas, mosquito control, and migratory bird control. For timely diagnosis, PCR and ELISA methods for WNV markers should be included in a comprehensive examination of patients with meningitis and meningoencephalitis, as well as with fever of unknown genesis with catarrhal syndrome, exanthema, and lymphadenopathy in the summer-autumn period in the southern regions of Russia.

Spatiotemporal Distribution of Methane Concentration and Emissions in the Northeastern Reservoir with Ice-Covered Characteristics

Climate-sensitive ice-covered reservoirs are critical components of methane (CH4) release. To reveal the spatial characteristics of CH4 concentrations, diffusive fluxes and bubble fluxes during the ice-covered and ice-free periods in northern reservoirs, and in order to clarify the critical influences on their variations. We selected Dongfeng Reservoir, a large reservoir in Northeast China, and conducted six field investigations of CH4 concentrations and emissions in deep and shallow waters during the ice-covered (January 2022 and January 2023) and ice-free (July 2022, October 2022, March 2023, and September 2023) periods. The results showed that spatially, surface CH4 concentration and diffusive flux were significantly higher in shallow water than those in deep water. CH4 bubble flux had the largest range of variation in shallow water, while there was no obvious spatial difference in the proportion of CH4 in bubbles. Temporally, surface CH4 concentration, diffusive flux, bubble flux, and the proportion of CH4 in bubbles were generally high in summer and low in autumn. The surface CH4 concentration had the largest range of variation in winter, and the CH4 concentration under the ice was significantly higher in shallow water than those in deep water. Water depth determines the release of CH4 bubbles from sediments and is the basis for determining deep and shallow water based on bubbles. Ice cover leads to significant differences in CH4 production and transport compared with ice-free periods by indirectly changing the water environment and directly altering the CH4 release. CH4 accumulated under the ice and in the ice will greatly increase the CH4 release potential during the spring ice-melt period. Overall, this study improves the understanding of CH4 emissions from reservoirs characterized by ice-covered periods and provides theoretical basis for comprehensive estimation of CH4 emissions from reservoirs.

Ant Colony Optimization for Accelerated Pathway Identification in Connection Element Method Reservoir Models: A Fast-Track Solution for Large-Scale Simulations

In recent years, reservoir models based on the Connection Element Method (CEM) have gained extensive application in reservoir development. This mesh-free modeling approach effectively captures all flow paths and flow-splitting coefficients between nodes, providing a clear view of flow interactions and accurately identifying primary connectivity pathways between injection and production wells. However, the traditional approach of traversing flow paths and splitting coefficients imposes a significant computational load, particularly when applied to large reservoirs with numerous virtual wells. To enhance simulation efficiency, this paper introduces a novel method leveraging the Ant Colony Optimization (ACO) algorithm to efficiently identify the path with the highest splitting coefficient between well pairs. This approach rapidly calculates and filters the dominant connectivity paths between injection and production wells in CEM models. A comparative analysis shows that, while the ACO algorithm provides limited benefit with a small number of connectivity paths, it significantly outperforms the conventional depth-first search algorithm as the number of experimental wells increases.

Seasonal water storage of large reservoirs exacerbates eutrophication risk in the fluctuating backwater zone: A case study of Three Gorges Reservoir, China

Seasonal water storage of large reservoirs exacerbates eutrophication risk in the fluctuating backwater zone: A case study of Three Gorges Reservoir, China

Baseline tritium measurements in Thailand's water bodies: Supporting sustainable nuclear energy development.

Baseline tritium measurements in Thailand's water bodies: Supporting sustainable nuclear energy development.

Microplastics in sandy soils: Alterations in thermal conductivity, surface albedo, and temperature.

Microplastics in sandy soils: Alterations in thermal conductivity, surface albedo, and temperature.

Evaluating 36 years of fishing sustainability in a large reservoir

Various fishing activities are common economic practices in large hydroelectric reservoirs, such as Itaipu. Consequently, the Itaipu company has monitored artisanal commercial fishing since the formation of its reservoir. In this study, we used long-term monitoring data to evaluate the sustainability of this fishing activity in the Itaipu Reservoir, one of the largest reservoirs in the Neotropical region. Sustainability was evaluated by analyzing raw data patterns, evaluating species abundance distributions, building surplus production models, and forecasting biomass under different fishing scenarios. This evaluation spanned 36 years (1987–2022) and provided insights into 25 fish stocks. Additionally, we examined changes in stocks before and after 2000, coinciding with the construction of a fish pass and Porto Primavera Dam, a large upstream hydroelectric power plant. Our results show that, even after 40 years since the formation of the reservoir, biomass yields continue to decline, with fishing not being the primary cause, and certain stocks only being recorded after 2000. In 2022, we identified 12 fish stocks as sustainable, nine as recovering biomass, and four as overfished. We consider fishing in the Itaipu Reservoir to be currently sustainable, though concerns persist regarding the four overfished stocks and the decreasing biomass, which could pose future challenges for fishing activities in the reservoir. Additionally, the data suggests that even 40 years after the reservoir was formed, fish populations may not yet be stable in large reservoirs.