River Flow Research Articles

Predicting Stream Flows and Dynamics of the Athabasca River Basin Using Machine Learning

Streamflow forecasting is of great importance in water resource management and flood warnings. Machine learning techniques can be utilized to assist with river flow forecasting. By analyzing historical time-series data on river flows, weather patterns, and other relevant factors, machine learning models can learn patterns and relationships to present predictions about future river flows. In this study, an autoregressive integrated moving average (ARIMA) model was constructed to predict the monthly flows of the Athabasca River at three monitoring stations: Hinton, Athabasca, and Fort MacMurray in Alberta, Canada. The three monitoring stations upstream, midstream, and downstream were selected to represent the different climatological regimes of the Athabasca River. Time-series data were used for model training to identify patterns and correlations using moving averages, exponential smoothing, and Holt–Winters’ method. The model’s forecasting was compared against the observed data. The results show that the determination coefficients were 0.99 at all three stations, indicating strong correlations. The root mean square errors (RMSEs) were 26.19 at Hinton, 61.1 at Athabasca, and 15.703 at Fort MacMurray, respectively, and the mean absolute percentage errors (MAPEs) were 0.34%, 0.44%, and 0.14%, respectively. Therefore, the ARIMA model captured the seasonality patterns and trends in the stream flows at all three stations and demonstrated a robust performance for hydrological forecasting. This provides insights and predictions for water resource management and flood warnings.

Identifikasi dan Pemetaan Konsentrasi Salinitas dan Suhu Permukaan Laut di Pesisir Kabupaten Probolinggo dengan Data Citra Satelit Landsat-8

The coastal area of ​​Probolinggo City is flowed by six rivers, namely the Kedunggaleng River, Umbul River, Banger River, Legundi River, Kasbah River and Pancur River. With an average flow length reaching 3.80 km. The river flows throughout the year from the south to the north according to the slope of the coastal area of ​​Probolinggo City. These activities can result in interactions between fresh water and sea water. This interaction influences the distribution pattern of salinity and sea surface temperature in the Probolinggo Coastal waters. Salinity and sea surface temperature are one of the biggest factors causing corrosion in the sea which can damage building structures around the sea. Based on this background, research is needed to monitor the distribution of salinity and sea surface temperature values ​​for 2020 to 2024 on the Probolinggo Coast using Landsat-8 satellite imagery. In this research, direct sample collection and measurement were used, for measuring salinity values ​​a Refractometer was used for sea surface temperature using an Infrared Thermometer. After data collection, regression and ANOVA tests were carried out on the data with the aim of finding out whether there were differences in in-situ data with sensor data from Landsat-8 satellite imagery. The results of the algorithm modeling were obtained, the algorithm model for processing image salinity was the Band_3 wavelength with the Logarithmic equation with y = 10.534ln(x) + 58.369 and the degree of determination value R^2 = 0.2499. Meanwhile, for sea surface temperature, the Exponential equation is y = 25.637e^3.1286x and the degree of determination R^2 = 0.0847. The analysis results from the ANOVA test for the H1 salinity value are accepted, meaning there is a significant difference between the in situ salinity value and the Landsat-8 satellite image salinity value from 2020 to 2024. Meanwhile, for the H1 sea surface temperature, it is accepted, meaning there is a significant difference between in situ SST and Satellite image SST from 2020 to 2024.

River mouths are hotspots for terrestrial organic carbon burial on the Sunda Shelf: Implications for tropical coastal carbon sequestration

Tropical small mountainous rivers (SMRs), characterized by extensive basin weathering, discharge high amounts of sediments and particulate terrestrial organic carbon (OCterr) into the ocean. Burial of OCterr in marine sediments is important for atmospheric CO2 sequestration, yet its rate and efficiency remain not fully understood. Previous studies indicated generally low burial rates and burial efficiencies of OCterr in tropical coastal ocean settings influenced by SMRs but lacked detailed insights into specific processes and quantitative estimates of burial efficiencies. This study investigated δ13C values of bulk OC (δ13COC) and OCterr biomarker proxies (BIT, #ringstetra, ΣIIIa/ΣIIa and %C32 1,15-diol indices) in river surface sediments on the Malay Peninsula and marine surface sediments on the adjacent Sunda Shelf to quantify sedimentary OCterr contents, burial rates, and burial efficiencies along the river-estuary-ocean continuum. The substantial variation in δ13COC and OCterr biomarker proxies between riverbed and shelf sediments revealed a strong decrease in fractional OCterr contribution offshore and alongshore. Using a two-endmember mixing model based on δ13COC, we determined average OCterr contents of 1.40, 0.80, and 0.05 wt% in riverbed, river-mouth, and shelf sediments, respectively. The low OCterr contents in offshore sediments are attributed to physical mechanisms (such as local hydrodynamic regime and clay mineral flocculation) that affect sediment dispersal. This process leads to notably high burial rates of terrigenous sediment (11.5 ± 2.1 kg/m−2(−|-) yr−1) and OCterr (99.2 ± 29.0 g/m−2(−|-) yr−1) at river mouths. In comparison, burial rates of OCterr were significantly lower (0.1–0.5 g/m−2(−|-) yr−1) offshore due to strong degradation of OCterr, resulting in a lower overall OCterr burial efficiency across the study area (18.2 %) compared to the global marginal sea average (21 %). These findings highlight the significance of carbon burial at the mouths of SMRs as CO2 sinks, whereas degradation of OCterr during offshore transport is a potentially large CO2 source in the tropical coastal ocean.

The transport and vertical distribution of microplastics in the Mekong River, SE Asia

Rivers are primary vectors of plastic debris to oceans, but sources, transport mechanisms, and fate of fluvial microplastics (<5mm) remain poorly understood, impeding accurate predictions of microplastic flux, ecological risk and socio-economic impacts. We report on microplastic concentrations, characteristics and dynamics in the Mekong River, one of the world’s largest and polluting rivers, in Cambodia and Vietnam. Sampling throughout the water column at multiple localities detected an average of 24 microplastics m-3 (0.073mgl-1). Concentrations increased downstream from rural Kampi, Cambodia (344km from river mouth; 2 microplastics m-3, 0.006mgl-1), to Can Tho, Vietnam (83km from river mouth; 64 microplastics m-3, 0.182mgl-1) with most microplastics being fibres (53%), followed by fragments (44%) and the most common polymer being polyethylene terephthalate (PET) or polyester. Pathways of microplastic pollution are expected to be from urban wastewater highlighting the need for improved wastewater treatment in this region. On average, 86% of microplastics are transported within the water column and consequently we identified an optimum sampling depth capturing a representative flux value, highlighting that sampling only the water surface substantially biases microplastic concentration predictions. Additionally, microplastic abundance does not linearly follow discharge changes during annual monsoonal floods or mirror siliclastic sediment transport, as microplastic concentrations decrease rapidly during higher monsoon flows. The findings reveal complex microplastic transport in large rivers and call for improved sampling methods and predictive models to better assess environmental risk and guide policy.

Perspectives on Northern Gulf of Alaska salinity field structure, freshwater pathways, and controlling mechanisms

The biologically productive Northern Gulf of Alaska (NGA) continental shelf receives large inputs of freshwater from surrounding glaciated and non-glaciated watersheds, and a better characterization of the regional salinity spatiotemporal variability is important for understanding its fate and ecological roles. We here assess synoptic to seasonal distributions of freshwater pathways of the Copper River discharge plume and the greater NGA continental shelf and slope using observations from ship-based and towed undulating conductivity-temperature-depth (CTD) instruments, satellite imagery, and satellite-tracked drifters. On the NGA continental shelf and slope we find low salinities not only nearshore but also 100-150 km from the coast (i.e. average 0–50 m salinities less than 31.9, 31.3, and 30.8 in spring, summer, and fall respectively) indicating recurring mid-shelf and shelf-break freshwater pathways. Close to the Copper River, the shelf bathymetry decouples the spreading river plume from the direct effects of seafloor-induced steering and mixing, allowing iron- and silicic acid-rich river outflow to propagate offshore within a surface-trapped plume. Self-organized mapping analysis applied to true color satellite imagery reveals common patterns of the turbid river plume. We show that the Copper River plume is sensitive to local wind forcing and exerts control over water column stratification up to ∼100 km from the river mouth. Upwelling-favorable wind stress modifies plume entrainment and density anomalies and plume width. Baroclinic transport of surface waters west of the river mouth closely follow the influence of alongshore wind stress, while baroclinic transport east of the river mouth is additionally modified by a recurring or persistent gyre. Our results provide context for considering the oceanic fate of terrestrial discharges in the Gulf of Alaska.

Nitrogen, sulfur, iron, and microbial communities co-shape the seasonal biogeochemical behaviors of As and Sb in coastal tidal flat wetlands associated with rivers

Arsenic (As) and antimony (Sb) are affected by complex biogeochemical processes in coastal ecosystems. However, the influence of N, S, Fe, and microbial communities on the biogeochemistry of As and Sb in coastal tidal flat wetlands remain uncertain, particularly when rivers flow into these areas. This study combined diffusive gradients in the thin-film technique with high-throughput sequencing to investigate the release and vertical distribution of As and Sb in river and coastal tidal flat wetland sediments. The results indicated a distinct stratification phenomenon in the As release at depths ranging from 20mm to −150mm. At river sites, the release of As occurred in the upper layer (above −40mm), with peak values of 4.3 and 9.3μg/L at HS and SY sites in summer, respectively, likely due to anaerobic ammonium oxidation. In the lower layer (below −40mm), both As and Sb were released, and this was possibly due to Fe reduction. However, at the coastal tidal flat sites, the release of As and Sb may have been driven by anaerobic ammonium oxidation, dissimilatory nitrate reduction to ammonium, sulfate reduction, and Fe reduction. At the river sites, As exhibited increased activity during the summer, and the residual forms were converted more easily into mobile forms. Sb remained relatively stable during both winter and summer. Conversely, both As and Sb primarily existed in residual forms and exhibited higher stability during summer in the coastal tidal flat sites. The microbial phyla Nitrospirota (3.6−7.0%) and Acidobacteriota (9.5−10.2%) were more prevalent at the river sites, whereas Desulfobacterota (8.8−12.0%) and Firmicutes (0.13−27.9%) were more prevalent at the coastal tidal flat sites. The bacterial genera involved in the N, S, and Fe transformation processes differed between the two sites, and they were primarily Thiobacillus, Limnobacter, and Sulfurovum at the river sites and Sva1033, Anaeromyxobacter, and Sva0485 at the coastal tidal flat sites. In this study, the microorganisms that mediated N, S, and Fe complex processes at various depths in the sediment–water interface were decoupled to elucidate the effect of these processes on the biogeochemical behavior of As and Sb as they move from rivers to coastal tidal flat wetlands. Environmental ImplicationCoastal wetlands have been experiencing heavy metal contamination, particularly in the estuarine regions affected by industrial activities. It is still not well understood how As and Sb behave biogeochemically in river and coastal tidal flat wetlands. This study provided an in-depth understanding of the effect of nitrogen, sulfur, iron, and microbial communities on the behavior of As and Sb in these areas. This study also highlights the eutrophication may increase As/Sb pollution in river areas. And these heavy metals may accumulate in seafood, potentially leading to heightened health risks of As and Sb poisoning in coastal tidal flat wetlands.

ABUNDANCE AND DIVERSITY OF PHYTOPLANKTON IN RIVER FLOWS IN BANJAREJO VILLAGE IN SUPPORTING THE PRODUCTIVITY OF TRADITIONAL PONDS IN BANJAREJO VILLAGE, LAMONGAN

Banjarejo Village River close by in a way direct with aquaculture areas so that the main water source used for irrigate pond originate from river water. Problems in the Banjarejo Village River is lack of management waste domestic nor waste activity agriculture can influence water quality and existence phytoplankton. Therefore that's the goal study this for know composition type, abundance, diversity, uniformity and dominance phytoplankton in rivers as material information management pond traditional and River. Taking sample done month December 2023 and January 2024 at time morning, afternoon and evening. Research sites found 3 stations. The main parameters observed covers abundance, diversity, uniformity and dominance phytoplankton. Meanwhile, the supporting parameters in the form of bulk data rain and water quality. Composition results type phytoplankton found in the Banjarejo Village River as many as 17 genera from 4 classes phytoplankton (Bacillariophyceae, Chlorophyceae, Cyanophyceae and Xanthophyceae). The value of abundance phytoplankton in the river flow in Banjarejo Village in the month December and January are included in type waters mesotrophic, index diversity medium, index even uniformity, and index dominance show that no there is a genus that dominates. Brightness, ammonia, nitrate and nitrite values in December and January overall exceeded the maximum limit. As for the test results of other parameters like temperature, DO, pH, salinity and phosphate still in optimal category for growth phytoplankton.

Reservoir Regulation Changed Terrestrial Particulate Organic Carbon Transport and Burial Processes off the Yellow River Mouth

AbstractThe dynamic behavior of particulate organic carbon (POC) is crucial for understanding biogeochemical carbon cycling in coastal and oceanic environments. However, intense watershed human activities have significantly altered the POC transport and burial in the estuary‐coast continuum. Here, we developed a novel parameterization scheme that incorporates grain‐size constraints to investigate the dispersal and accumulation processes of POC off the Yellow River mouth during the water‐sediment regulation scheme (WSRS) using a three‐dimensional hydrodynamic model (FVCOM). The result shows that the model successfully captures the offshore transport and hydrodynamic sorting of POC, which leads to a progressive increase in POC content with offshore dispersion and significant variations in POC and sediment deposition across different isobaths. Rapid fluctuations in river discharge and sediment composition during WSRS stages result in noticeable differences in sedimentation patterns for sediment and POC. At the Water‐regulation stage, distinct differences are observed in the distribution of riverine POC and sediment across various isobaths. In contrast, during the Sediment‐regulation stage, these differences are significantly reduced due to the finer riverine sediment. Compared to the sediment‐regulation, the Water‐regulation plays a crucial role in enhancing the effective burial of POC. Coarse‐grained sediment can form an armored layer that protects OC from disturbance. Additionally, increased runoff during this stage promotes the offshore transport of POC to a less energetic environment (&gt;10 m in depth). This study provides valuable insights into POC dynamics in high‐turbidity estuarine and coastal environments. It underscores the importance of employing comprehensive modeling approaches to elucidate these complex processes.

Statistical analysis of water quality and cyclone impacts along the south Odisha coast, east coast of India

Water quality along south Odisha coast (25km stretch), east coast of India was studied collecting monthly samples at 10 different sampling stations from June 2008 to March 2011 and June 2012 to May 2017. The samples were analysed for salinity, dissolved oxygen (DO), total suspended solids (TSS) and pH. In addition, river discharge, siltation, rainfall and wind speed data were also collected from 2008 to 2017 at the study region and their impacts on coastal water quality were assessed along with the impacts of cyclonic storms. Anomalies of water quality parameters and their seasonal variability were assessed. Spatio-temporal variation of these parameters and multivariate statistical techniques such as factor analysis, correlation coefficient and, descriptive statistics were applied to the observed datasets. Results indicate that, salinity is positively correlated with wind speed at 0.05 significance level while negatively correlated with river discharge. TSS is positively correlated with siltation at 0.01 significance level. DO values are also positively correlated with strong wind speed. Nutrient driven primary production helps pH to be higher at Rushikulya river mouth during monsoon and post-monsoon as compared to at all other stations. Throughout the year, the study environment remains alkaline. Due to impacts of cyclonic storms, water quality parameters show significant reduction in salinity and enhancement in TSS, DO and pH during the post-cyclone period while the seasonal trend is maintained during the pre-cyclone period. Factor analysis reveals the factors controlling the hydrographic behaviour of seawater. The spatial variation in coastal water quality is very high and dominates over the temporal variation. Importance of coastal water quality assessment in relation to coastal ecosystem and disaster is discussed.

In search of non-stationary dependence between estuarine river discharge and storm surge based on large-scale climate teleconnections

Compound floods may happen in low-lying estuarine environments when sea level above normal tide co-occurs with high river flow. Thus, comprehensive flood risk assessments for estuaries should not only account for the individual hazard arising from each environmental variable in isolation, but also for the case of bivariate hazard. Characterization of the dependence structure of the two flood drivers becomes then crucial, especially under climatic variability and/or change that may affect their relationship. In this article, we demonstrate our search for evidence of non-stationarity in the dependence between river discharge and storm surge along the East and Gulf coasts of the United States, driven by large-scale climate variability, particularly El-Niño Southern Oscillation and North Atlantic Oscillation (NAO). Leveraging prolonged overlapping observational records and copula theory, we recover parameters of both stationary and dynamic copulas using state-of-the-art Markov Chain Monte Carlo methods. Physics-informed copulas are developed by modeling the magnitude of dependence as a linear function of large-scale climate indices, i.e., Oceanic Niño Index or NAO index. After model comparison via suitable Bayesian metrics, we find no strong indication of such non-stationarity for most estuaries included in our analysis. However, when non-stationarity due to these climate modes cannot be neglected, this work highlights the importance of appropriately characterizing bivariate hazard under non-stationarity assumption. As an example, we find that during a strong El-Niño year, Galveston Bay, TX, is much more likely to experience a coincidence of abnormal sea level and elevated river stage.

MONITORAMENTO DE RECURSOS HIDRÍCOS POR ALTIMETRIA ESPACIAL

Although most of the space missions discussed here have not been primarily dedicated to hydrology, 31 years of spatial altimetry have provided complementary data that can be used to create hydrological products for watersheds, such as time series water levels, estimates of river flows, longitudinal riverbed altitude profiles, minimum and maximum elevations, or leveling of stations in situ. The raw data still suffer from uncertainties of several decimeters. Today, altimetry techniques are evolving rapidly. One direction is the change of the radar band, from Ku to Ka. Another change is the replacement of the current LR Mode with SAR or Interferometry modes. Both evolutions tend to drastically decrease the imaged range, reducing both the contamination of the echo by the environment of the water body, and improving the vertical accuracy. Finally, as of 2015, the research missions were replaced by operational ones, making the longevity of the sampling sites more certain. All the aforementioned technical evolutions have been grouped together in the SWOT mission, a Ka-band interferometric altimeter, the first satellite mission actually dedicated to providing full coverage of continental waters, launched in December 2022.

Heterogeneous long-term and seasonal brine evolution, and Artemia fecal pellet controls on Urmia Lake (NW Iran) salt-crust formation and mineralogy

ABSTRACT Urmia Lake resides as a substantial hypersaline lake characterized by notable fluctuations in water salinity, brine composition, and water level over long-term, annual, and seasonal intervals. Extremely rapid water elevation fall (&amp;gt; 7 m) in the last three decades has caused the formation of a salt crust on the lake floor. A manmade stone causeway divided the lake into two relatively deeper northern parts with minimal water inputs and a shallower southern part with maximal river inflows. Restricted water flow through the narrow water passage of the causeway leads to complex salinity processes, brine evolution, and salt-crust formation in Urmia Lake. This research analyzes the ionic composition of lake-sediment and salt-crust pore water, the mineralogy of salt crusts, and the ionic composition of both surface and deep lake waters during both the wet and dry seasons of 2019. The findings indicate that the northern and southern parts of the lake undergo stratification during wet seasons due to significant freshwater input, whereas they become homogenized during dry seasons through progressive evaporative concentration and water mixing. The spatial and temporal variations in the lake brine type (primary Na-Mg-Cl) and ionic composition contribute to the formation of a halite salt crust (NaCl &amp;gt; 97%) with heterogeneous mineralogy and thickness. In Urmia Lake, the variable thickness and mineralogy of the exposed marginal salt crust suggest rapid salt-crust reorganization by annual and seasonal deposition and dissolution processes. Conversely, the submerged central salt crust, with continuous thickening and constant mineralogy, remains unaffected by seasonal variations in brine type and dissolution processes. It is noteworthy to mention that Artemia (a brine shrimp) controls the mineralogy of the lake salt crust through the deposition of calcium and carbonate ions in the form of biochemical fecal pellets.

The eastward intrusion of the Lena River into the East Siberian Sea since the early Holocene

The sedimentary environments and material sources of the eastern and northeastern Lena Delta differ in coarse-grained components and garnet geochemistry, particularly in the Buor-Khaya Bay, where the material composition is primarily influenced by the Lena River, while the Yana Bay sediment is controlled by the Yana River. Analysis of detrital minerals in core LV83–32-3, located in northern Yana Bay, indicates dominant primarily fluvial input from the Yana River, with secondary contributions from the Lena River and minor inputs from coastal permafrost erosion since the early Holocene. During the sea-level rise period from 8.5 to 5 ka, four significant fluvial discharge events from the Yana River were identified, marked by high mica contents, associated with multiple climate warming events. From ∼5 to 1.6 ka, an increasing Lena River runoff transported coastal permafrost material via river flow or river ice, evident in a gradual rise in plagioclase content. After 1.6 ka, a sharp decrease in hypersthene and garnet contents suggests reduced Lena River discharge, coinciding with a similar decline in hypersthene content in the core of the East Siberian Sea since 1.8 ka. Two prominent Lena River fluvial events, dated to 7.1 and 3.7 ka, are identified by the event layers containing minerals typical of the Lena River, rich in hypersthene, garnet and zircon, along with substantial coarse-grained debris such as quartz, plagioclase, siderite and clayey tubes. These two events are also recorded in the East Siberian Sea. The 7.1 ka discharge event may coincide with the separation of the New Siberian Islands from the mainland, while the 3.7 ka event represents a widely distributed Lena River floodplain event.

Differential tectonic activity along the southern boundary of the Qilian Mountains: Insights from low-temperature thermochronology, seismic data, and fluvial geomorphology

The Cenozoic development of the Tibetan Plateau is one of the most remarkable events in the geosciences. The southern boundary of the Qilian Mountains is a spectacular basin-mountain boundary in the northern Tibetan Plateau offering a valuable opportunity to investigate the growth processes and mechanisms of the Tibetan Plateau. Structural activity is significantly variable across the northern Qaidam basin, and the underlying reason for these differences remains uncertain. To address this issue, we undertook an analysis of two main watersheds—the Tataleng and Yuqia River watersheds—encompassing the middle section of the northern Qaidam basin. This study utilized a multidisciplinary approach combining fluvial geomorphology, low-temperature thermochronology, and seismic data to comprehensively investigate the structural activity within the northern Qaidam basin. The high channel steepness index, young low-temperature thermochronologic ages, concentrated earthquakes, and numerous knickpoints along the piedmont area of the Qaidam Shan collectively suggest that this region is among the most structurally active areas along the southern boundary of the Qilian Mountains. The varying levels of structural activity in the northern Qaidam basin could be linked to the intense glacial erosion in the Qaidam Shan during the Quaternary. Moreover, the flow orientation observed in the bedrock mountains is consistent with the N-S compressional stress field in the northern Qaidam basin during the early Cenozoic, representing a stark contrast to the modern NE-SW stress field. In this way, this research supports the understanding that river geomorphic parameters, including river steepness index and flow direction, are valuable tools for unveiling the regional tectonic evolution in bedrock mountain areas.

Analysis of Stakeholder Discourses on Petroleum Exploration and Production in the Brazilian Equatorial Margin

The exploration and production (E&amp;amp;P) of oil and natural gas in the Brazilian Equatorial Margin, particularly at the Amazon River Mouth, has become a subject of intense national and international debate. This study analyzes public discourses related to those activities within the context of Brazil&amp;rsquo;s environmental commitments under the Paris Agreement. The analysis spans the period from President Lula da Silva&amp;rsquo;s third inauguration, in January 2023, to May 2024, focusing on political and economic approaches. The method involved systematic literature review, discourse analysis, and content analysis, using the Atlas TI software as a content analysis tool to manage, code and categorize textual data. The results show the predominance of the right to development, ecological modernization, and energy clout narratives. The common but differentiated responsibilities narrative is deeply rooted in these dominant narratives and undermines the opposition to oil production in the Brazilian Equatorial Margin. The analysis reveal the complexity of the discursive coalitions formed and simultaneously offers insights to help public policymakers balance economic development, energy security, and environmental sustainability.

Climate shapes baseflows, influencing drought severity

Abstract Baseflow, the sustained flow from groundwater, lakes, and snowmelt, is essential for maintaining surface water flow, particularly during droughts. Amid rising global water demands and climate change impacts, understanding baseflow dynamics is crucial for water resource management. This study offers new insights by assessing baseflow controls at finer temporal scales and examining their relationship with hydrological drought flows. We investigate how climatic factors influence seasonal baseflow in 7138 global catchments across five major climate regions. Our analysis identifies precipitation as the primary driver, affecting 58.3% of catchments, though its impact varies significantly across different climates. In temperate regions, precipitation dominates (61.9% of catchments), while in tropical regions, evaporative demand is the leading factor (47.3%). Snow fraction is particularly crucial in both snow-dominated (20.8%) and polar regions (48.5%). Negative baseflow trends generally emerge where the effects of evaporative demand or snow fraction outweigh those of precipitation. Specifically, in northern regions and the Rocky Mountains, where snow fraction predominantly controls baseflow changes, a negative trend is evident. Similarly, in tropical catchments, where evaporative demand drives baseflow changes, this also leads to a negative trend. Additionally, our findings indicate that baseflow changes are closely linked to hydrologic drought severity, with concurrent trends observed in 69% of catchments. These findings highlight the relationship between baseflow changes, the severity of hydrologic drought and shifts in precipitation, evaporative demand, and snow dynamics. This study provides crucial insights for sustainable water resource planning and climate change adaptation, emphasizing the importance of managing groundwater-fed river flows to mitigate drought impacts.

Establishment of Regional Regulations For Coastal Area Rehabilitation As An Environmental Restoration Effort In Buru District

Introduction: Research entitled "Establishment of Regional Regulations for Coastal Area Rehabilitation as an Environmental Recovery Effort in Buru Regency". Purposes of the Research: The specific aim of this research is to find out and analyze the impact of traditional mining activities on environmental damage in coastal areas, especially in Kayeli Bay, Buru Regency as the estuary of rivers affected by mining activities and to find and analyze the importance of establishing Regional Rehabilitation Regulations as an effort to restore the marine and coastal environment. in Buru Regency.Methods of the Research: This research uses an exploratory type of empirical normative research. This research approach is a statutory approach, a concept approach and a case approach. The data collection techniques used in this research were interviews and literature study.Results of the Research: Mining activities using dangerous chemicals carried out over a period of 23 years have had a major impact on the environmental conditions of Buru Regency. Environmental pollution and destruction not only occurs in mining areas but also land, river flows, bays, coasts and seas which are the final estuaries of mining remains. Kayeli Bay is an important area for fishing, to support the daily lives of around 50,000 village communities. coast. Kaiely Bay is located between 3º 15' 55” - 3º 22' 50” S and 127º 01'35”-127º 01'35” E and is an estuary in nature because it is influenced by the surrounding land, through runoff that enters through rivers that empties into the bay. Continuous abundance of nutrients causes an increase in water fertility. On the other hand, Kaiely Bay is also able to supply and fertilize the surrounding waters with nutrients and a high concentration of chlorophyll-a, namely &gt; 6 mg/L.

Characteristics of Mudflow Distribution and Evolution of Mudflow Fan in Erlian Village

Debris flow in the upper Yellow River is very developed and is generally characterized by wide distribution with large numbers and a high frequency of occurrence. This paper analyses the distribution characteristics, material composition, and formation causes of the Erlian debris flow fan in the eastern part of the Guide Basin and discusses the relationship between debris flow fan and river evolution. Results show that: (1) At least 66 debris flow gullies and 20 large debris flow accumulation fans have been developed on both sides of the Yellow River in the eastern Guide Basin. (2) In the Erlian Village area, the Yellow River channel has experienced the accumulation, erosion, destruction, and accumulation process of debris flow fans in 16 kaB.P., 16 ka B.P.–8 ka B.P., and 8 kaB.P., respectively, the late-accumulation fan has been continuously extruding the Yellow River channel since 8 kaB.P., and the Yellow River channel has been shifted to the south by at least 1.25 km during the period of 8 ka. (3) Five accumulation periods for the Late Mudslide Fan were identified by classifying the 16 kaB.P. and 8 kaB.P. early and late mudslide fans. This study can provide theoretical and technical support for preventing debris flow disasters in the upper reaches of the Yellow River and has certain reference and reference values.

Unexpected Transient Dynamics of Meandering Rivers With Unsteady Flows

AbstractRiver meandering dynamics are here explored in light of unsteady water flows. While mathematical models have usually focused on constant discharges—a reasonable and widely adopted approach for long‐term considerations—we show that varying flows strongly affect the short‐term planimetric evolution of meanders, before the cutoff occurrence. In particular, flow variability slows down the meanders' dynamics while does not significantly influence the wavelength selection. We support our arguments with numerical simulations and theoretical (linear and nonlinear) analyses, showing that an interplay between out‐of‐phase river geometry and flow is responsible for the meander‐dynamics slowdown. Our results suggest that accounting for flow variability is critical in assessing yearly to decadal meander dynamics with important implications for river engineering and management strategies.

A framework for generating rating curves in Mahanadi River using hydrodynamic model and radar altimetry data

ABSTRACT The limited availability of in-situ data has drawn attention towards using remote sensing techniques to monitor river flow. Radar altimetry data has been used to generate stage-discharge rating curves through power-law relations and empirical methods. However, evaluating hydrodynamic models for rating curve generation using multi-mission altimetry data in data-scarce regions is lacking. We used altimetry data (Jason 2, Jason 3, SARAL/AltiKa, Sentinel 3A, and Sentinel 3B) over the Mahanadi River to evaluate rating curves at virtual stations. The HEC-RAS hydrodynamic model was set up, identifying seven virtual stations along the Mahanadi River from Boudh to Mundali Barrage. Statistical evaluation of ‘water level’ (RMSE 0.27-0.88 m) and ‘discharge’ (KGE 0.52 to 0.88) components of the generated rating curves showed significant agreement with radar altimetry data. These rating curves at virtual stations offer a cost-effective tool for monitoring river flows at additional locations.