Hydrological Characteristics Research Articles

Effect of Nostoc commune cover on shallow soil moisture, runoff and erosion in the subtropics

Nostoc commune (Nostoc commune Vaucher ex Born & Flahault) is widely distributed in grasslands within the subtropical region. Because of its morphological changes are more sensitive to moisture, it may affect the soil’s response to infiltration-runoff processes, thus significantly influencing soil moisture dynamics, runoff, and soil loss. However, the exact effects of this phenomenon are not yet fully understood. This study established a one-year monitoring experiment of soil moisture, runoff and soil erosion in the karst area of Southwest China from September 2021 to November 2022. Using bare soil (CK) as the control, two treatments of Nostoc commune cover at 100 % coverage (C1) and 50 % coverage (C2) were set up in 3 repetitions to investigate the shallow soil’s response to Nostoc commune cover and rainfall and to quantify the effects of land cover and rainfall type on runoff and soil loss. The results showed that Nostoc commune cover significantly increased the shallow-soil water content, and the effect of increasing soil water content was more significant with increasing coverage. The cumulative soil water increment (CSWI) varied greatly under different types of rainfall due to the high water-absorbing capacity of Nostoc commune. The CSWI showed C1 < C2 < CK under light rain and moderate rain events, while the CSWI showed C1 > C2 > CK under heavy rain and rainstorm events. The temporal pattern of soil moisture changed greatly under different cover treatments and rainfall events. In particular, the response time under different rainfall types varied from 10 min to 250 min. The runoff depth and soil loss in CK were 1.19–2.15 times and 1.92–14.43 times that of C1 and C2, respectively. This indicates that Nostoc commune cover has a significant effect on controlling runoff and soil erosion. In addition, the sensitivity of runoff and soil loss to the maximum 10-min rainfall intensity was higher than that of the maximum 30-min rainfall intensity, which was attributed to the rapid swelling of Nostoc commune in the hydration process, which greatly reduced runoff and soil erosion. This study can contribute to further understanding the hydrological process and soil erosion characteristics under different surface covers in humid karst areas.

Структура и динамика гидробиоценозов (фитоперифитон, зоопланктон, зообентос) рек Карельского побережья Белого моря.

This paper summarizes the results of the studies of biota structural organization and dynamics of small rivers of the Karelian White Sea coast. The chemical features and the structure of biological communities in the watercourses were investigated. Analysis of the species composition, abundance and biomass of phytoperiphyton, zooplankton, and zoobenthos was carried out. Variations in the structure of aquatic communities primarily are due to specific hydrographic and hydrological characteristics of river stretches. The paper discusses the main principles of the changes in a structure and functioning of hydrobiont communities in rivers. The trophic status of the rivers, their saprobiological state, and the significance of individual communities and biotic indices for bioindication of the ecological state of the rivers,are estimated. We concluded that the consideration of three groups of organisms enables a more comprehensive and reliable monitoring than the assessment based on a single group.

Water Resources Management In Small Islands: A Review of Public Policy Implementation In The Development of Lekloor Reservoir, Nomaha Island

Water scarcity in small island regions, including Kisar Island in Maluku, presents a pressing issue due to inadequate water resource management. This article aims to describe a holistic approach to addressing the challenges of water resource management and water scarcity on Kisar Island, Maluku. The research methodology employed is a mixed-method approach, combining technical feasibility studies for reservoir technology, policy analysis through literature reviews, and field assessments to evaluate the topographic, hydrological, and environmental conditions of Kisar Island. In the technical context, the article analyzes reservoir technology as a solution to address water issues, supported by the topographic and hydrological characteristics of Kisar Island. Additionally, the article examines relevant public policies, such as Government Regulation No. 7 of 2013 on National Spatial Planning, Provincial Regulation No. 16 of 2013 on Provincial Spatial Planning in Maluku, and District Regulation No. 1 of 2023 on District Spatial Planning in Maluku Barat Daya. Through this review, the article highlights the crucial role of policy in establishing a supportive framework for water resource management. Furthermore, the importance of local community participation in water resource management on Kisar Island is emphasized, asserting that active engagement from the local community is key to achieving success in sustainable water management efforts.

Rainfall-runoff modelling using GIS based SCS-CN method in umiam catchment region, Meghalaya, India

Rainfall-runoff is a crucial parameter and is often applied in assessing water resources. It is a significant constituent for recharging groundwater and plays an important role in understanding the hydrological characteristics of a basin for watershed management practices. In the current work, the soil conservation service-curve number (SCS–CN), coupled with GIS and remote sensing techniques, has been utilized to estimate the runoff and discharge in the Umiam Catchment area of Meghalaya for the years 2011 and 2020. This area receives heavy rainfall throughout the year, which contributes to the degradation of topsoil and the initiation of landslides. The rainfall-runoff modelling incorporates various thematic layers prepared in the GIS platform to calculate the weighted CN value. The antecedent moisture condition (AMC) was applied for CN correction. Both annual and monthly runoff and discharge were calculated for a total of four sub-watersheds. The result showed that land alteration and an increase in rainfall have been the predominant reasons for an increase in runoff in 2020 compared to 2011. Comparing both years, agricultural land, built-up, and open scrub have increased followed by shrinking open and dense forests. Sub-watersheds 2 and 4 had critical discharge changes of 75.95 and 75.82 cubic meters per second (cumec) from year 2011–2020 respectively. This study emphasizes the efficacy of SCS-CN method for simulating and estimating the runoff of a basin for better watershed planning and sustainable management at the regional level. It may also help in recognizing and examining the characteristics and volume of water resources.

Assessment of Hydrological and Meteorological Composite Drought Characteristics Based on Baseflow and Precipitation

Traditional univariate drought indices may not be sufficient to reflect comprehensive information on drought. Therefore, this paper proposes a new composite drought index that can comprehensively characterize meteorological and hydrological drought. In this study, the new drought index was established by combining the standardized precipitation index (SPI) and the standardized baseflow index (SBI) for the Jiaojiang River Basin (JRB) using the copula function. The prediction model was established by training random forests on past data, and the driving force behind the combined drought index was explored through the LIME algorithm. The results show that the established composite drought index combines the advantages of SPI and SBI in drought forecasting. The monthly and annual droughts in the JRB showed an increasing trend from 1991 to 2020, but the temporal characteristics of the changes in each subregion were different. The accuracies of the trained random forest model for heavy drought in Baizhiao (BZA) and Shaduan (SD) stations were 83% and 88%, respectively. Furthermore, the Local Interpretable Model-Agnostic Explanations (LIME) interpretation identified the essential precipitation, baseflow, and evapotranspiration features that affect drought. This study provides reliable and valid multivariate indicators for drought monitoring and can be applied to drought prediction in other regions.

Critical linkages among floodplain hydrology, geomorphology and ecology along a lowland meandering river, Illinois, USA

AbstractThe ecology of forested floodplains is intricately linked to river hydrology through the frequency, magnitude, timing and duration of floodplain inundation. Spatial variability in inundation characteristics is influenced by the geomorphic template of a floodplain, both in terms of the topography of floodplain features and connectivity of these features to the main river channel. Spatial variability in inundation, in turn, has the potential to produce spatial variability in forest ecological characteristics. This study examines the influence of floodplain geomorphic features on spatial variability in inundation frequency as well as the relationship between these geomorphic features and the ecological characteristics of a floodplain forest. The frequencies of floods of different magnitudes are determined from flow‐duration analysis of over 100 years of discharge data for a lowland meandering river in Illinois, USA. Data on discharge, stage, and topography are then used to calibrate a two‐dimensional hydraulic model of flow across the floodplain at different levels of inundation. Integrating the frequency and inundation data yields mapping of average annual inundation frequency for different parts of the floodplain. Significant differences in inundation frequency correspond to three distinct floodplain geomorphic features: secondary channels (frequency = 12%), closed depressions (frequency = 4%) and the floodplain surface (frequency = 3%). Tree density is similar among the three types of geomorphic features, but tree species composition and canopy density differ significantly between secondary channels and the floodplain surface. The results provide insight into linkages among hydrology, geomorphology and tree characteristics of forested floodplains of lowland meandering rivers.

Morphometric Analysis of Waghora Micro Watershed of Jam River Basin Using ALOS-PALSAR DEM

Intergrating Remote sensing and Geographic Information System(GIS) Proves useful for Evaluating and understanding morphometric parameters, especially Watershed Management of - Soil and Water Conservation at microlevel for sustainable Natural Resource management. The Linear , Areal and Relief characteristics of the basins Drainage can be analytsed Morphometrically. In this investigation, geospatial techniques were employed to assess the hydrological features of the Waghora Micro watershed within the Jam River basin, covering an area of 13.03 km². Utilizing the ALOS-PALSAR RTC DEM -12.5 m resolution, the basin and drainage network were delineated using ArcGIS software. The analysis revealed a dendritic drainage pattern within the Waghora micro-watershed, with drainage streams delineated up to the fourth order. The ratio of bifurcation (Rb) can be ranged within ~ 3 - 4.66, with an mean average of 3.76, showcases Geologic Structures are undistorted and the drainage system sorted by moderate peaks and lower orer streams. Additional morphometric parameters were assessed, using Form-factor(Rf), Circulatory-Ratio(Rc), and finally Elongation-Ratio(Re) values of 0.32, 0.68, and 0.62 respectively. This is a clear indication of Micro watershed being moderately Elongated with time. The Estimated Relief, Relief Ratio(Rr), relative Relief (RR) and Ruggedness Ratio Number were determined to be 75 m, 1.2, 0.97, respectively, indicating a moderate erosion potential. Overall, the study underscores the necessity for implementing – Soil and Water Conservation measures to be taken within the watershed. These findings hold significant implications for various stakeholders, including managers and decision-makers involved in Management of Watersheds and Conservation of the Natural resources using sustainable initiatives.

Manganese exposure from spring and well waters in the Shenandoah Valley: interplay of aquifer lithology, soil composition, and redox conditions

Manganese (Mn) is of particular concern in groundwater, as low-level chronic exposure to aqueous Mn concentrations in drinking water can result in a variety of health and neurodevelopmental effects. Much of the global population relies on drinking water sourced from karst aquifers. Thus, we seek to assess the relative risk of Mn contamination in karst by investigating the Shenandoah Valley, VA region, as it is underlain by both karst and non-karst aquifers and much of the population relies on water wells and spring water. Water and soil samples were collected throughout the Shenandoah Valley, to supplement pre-existing well water and spring data from the National Water Information System and the Virginia Household Water Quality Program, totaling 1815 wells and 119 springs. Soils were analyzed using X-ray fluorescence and Mn K-Edge X-ray absorption near-edge structure spectroscopy. Factors such as soil type, soil geochemistry, and aquifer lithology were linked with each location to determine if correlations exist with aqueous Mn concentrations. Analyzing the distribution of Mn in drinking water sources suggests that water wells and springs within karst aquifers are preferable with respect to chronic Mn exposure, with < 4.9% of wells and springs in dolostone and limestone aquifers exceeding 100 ppb Mn, while sandstone and shale aquifers have a heightened risk, with > 20% of wells exceeding 100 ppb Mn. The geochemistry of associated soils and spatial relationships to various hydrologic and geologic features indicates that water interactions with aquifer lithology and soils contribute to aqueous Mn concentrations. Relationships between aqueous Mn in spring waters and Mn in soils indicate that increasing aqueous Mn is correlated with decreasing soil Mn(IV). These results point to redox conditions exerting a dominant control on Mn in this region.

Changes in the structure of the hydrological characteristics of the estuary mixing zone of the Pregolya River (South-East Baltic) during saline water inflow period in autumn

Changes in the structure of the hydrological characteristics of the estuary mixing zone of the Pregolya River (South-East Baltic) during saline water inflow period in autumn

Changes in the structure of the hydrological characteristics of the estuary mixing zone of the Pregolya River (South-East Baltic) during saline water inflow period in autumn

Changes in the structure of the hydrological characteristics of the estuary mixing zone of the Pregolya River (South-East Baltic) during saline water inflow period in autumn

Landslide Susceptibility Mapping Using Machine Learning: A Case Study of Oregon

Landslide susceptibility assessment, a crucial component of disaster prevention and mitigation, has traditionally relied on geological datasets and commonly used evaluation metrics. However, these metrics, often applied to 2D susceptibility maps, may not capture the full complexity of the issue. In this study, we incorporated spatial distribution data, including a historical landslide inventory, and integrated morphological, geological, hydrological, and land-use features. This approach enabled the construction of predictive models using eight distinct algorithms. The evaluation of classifier performance scores unveiled the superior performance of gradient tree boosting. In contrast, logistic regression struggled to handle the nonlinear aspects of landslide susceptibility analysis. A finding in our research was the consistent disparity in predictive susceptibility maps, even when similar performance scores were achieved across different algorithms. This underscores the necessity of combining evaluation metrics with spatial mapping in landslide susceptibility model assessment. We also highlighted the critical role of digital elevation models in constructing effective models when feature data was limited. Conversely, when abundant information was available, the integration of multi-source data significantly enhanced the precision of landslide susceptibility mapping. Overall, this study provides valuable insights for spatial prioritization in landslide field investigations and enhances our understanding of landslide risk assessment.

Insights to the water balance of a Boreal watershed using a SWAT model

The hydrological characteristics of a watershed play a crucial role in shaping ecosystems within the Boreal zone and have a significant impact on regional environments. Knowing these characteristics, such as the distinctive topography, vegetation, soil composition, and climatic conditions in the Canadian Boreal ecozone, is essential for implementing sustainable water management. This study focuses on assessing the hydrological dynamics of the Upper Humber River Watershed (UHRW) in western Newfoundland, Canada, using the Soil and Water Assessment Tool (SWAT) model. The UHRW includes sub-basins and hydrological response units (HRUs), with diverse land uses, soil types, and slope characteristics. Key parameters influencing streamflow simulation were identified through sensitivity analysis, including the runoff curve number, the effective hydraulic conductivity, the temperature lapse rate, the soil evaporation compensation factor, and the available water capacity of the soil layer. The SWAT model, using data from the Reidville hydrometric station, shows favorable performance metrics, with R2 values of 0.79 and 0.83 during the calibration and evaluation periods, respectively. The model effectively captures seasonal and monthly flow patterns, displaying right-skewed distributions and seasonal variations. The analyzed hydrological parameters, such as precipitation, evaporation, transpiration, surface runoff, and groundwater flow, reveal their significant contributions to the water balance. The flow duration curve analysis indicates the model’s capability to estimate peak and low flows, with slight under-prediction during the recession phase. Seasonal analysis further supports the model’s performance, with positive Nash-Sutcliffe Efficiency (NSE) values ranging from 0.65 to 0.91. The study concludes that the SWAT model is suitable for simulating the hydrological processes in the studied watershed providing valuable insights for sustainable water resource management and decision-making in the UHRW. The results can be useful for other Boreal ecozone watersheds.

Study on the vertical deformations induced by terrestrial water storage changes in Huang-Huai-Hai river basin

Terrestrial water storage (TWS) variations are associated with water mass movements, which may cause the deformation displacements of the Global Navigation Satellite System (GNSS) stations. This study investigates the spatio-temporal TWS variations and addresses the relationship between deformation variations observed in the Huang-Huai-Hai River Basin (HHHRB) and local hydrological features. Results indicate that the vertical velocities at the GNSS stations induced by TWS changes are relatively small, and the impacts of the terrestrial water storage changes are mainly reflected in the changes of seasonal characteristics. Although there is a downward TWS trend from 2011 to 2022 in most HHHRB areas, velocities from the vertical displacements of both Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GFO) and the GNSS reflect that the HHHRB is undergoing an uplift process, while the magnitude of the GRACE/GFO derived velocities is much smaller than that of the GNSS solutions. Common hydrological deformations estimated from GRACE/GFO and GNSS measurements reveal that the TWS-derived displacements can explain 54.5% of the GNSS seasonal variations, with the phases of terrestrial water storage advancing by about one month relative to GNSS common signal phases. Moreover, the decrease of the groundwater storage in the HHHRB has been accelerating since 2008. After reaching its lowest level around mid-2020, it began to rise rapidly, which might be closely related to the implementation of the South-North Water Transfer Central Project.

Strategi Konservasi Daerah Tangkapan Air Danau Singkarak

Land use changes that occur in the upstream areas of the watershed will certainly result in changes in the hydrological characteristics of the watershed. Area expansion in the form of land conversion, whether into residential or agricultural land, in the process often does not pay attention to soil and water conservation principles. Therefore, sustainable water catchment management is needed to reduce increasing land degradation. This research uses the Descriptive Analysis method through the Multidimensional Scaling approach. The sustainability status of the Lake Singkarak catchment area based on the results of the RapDTA analysis is in the moderately sustainable category with an index value of 54.87%. If we look at each dimension that is included in the quite sustainable category, it is the economic dimension with an index value of 55.10% and the social dimension with an index value of 50.37%, while the ecological dimension has an index value of 49.88%.

Changes in fronts regulate nitrate cycling in Zhanjiang Bay: A comparative study during the normal wet season, rainstorm, and typhoon periods

Typhoons and rainstorms (>250 mm/day) are extreme weather events changing hydrological characteristics and thus nitrogen (N) cycle in coastal waters. However, responses of N cycle to rainstorms and typhoons and their underlying mechanisms need to be elucidated. In this study, we conducted an analysis of a comparative dataset encompassing concentrations of nitrate (NO3−), ammonium (NH4+), dissolved oxygen (DO), chlorophyll a (Chl a), hydrological parameters, dual isotopic composition of NO3− (δ15N-NO3− and δ18O-NO3−) in Zhanjiang Bay during three distinct periods: the normal wet season, rainstorm, and typhoon periods. After the rainstorm, the salinity front in Zhanjiang Bay was more weakened and steadier than that during the normal wet season, mainly because onshore wind and a large amount of freshwater was inputted into the ocean surface. This weakened and steady salinity front strengthened water stratification and provided a favorable condition for phytoplankton blooms. Correspondingly, evident NO3− deficits coincided with elevated δ15N-NO3− and δ18O-NO3− values indicated that sufficient NO3− sustained phytoplankton blooms, leading to NO3− assimilation during the rainstorm period. By contrast, due to the onshore wind induced by the typhoon, the salinity front in Zhanjiang Bay was more intensified and unsteady after the typhoon than the normal wet season. The salinity front after the typhoon was unsteady enough to enhance vertical mixing in the water column. Relatively high DO concentrations suggested that enhanced vertical mixing after the typhoon support freshly organic matter decomposition and nitrification via oxygen injection from the air into the water column. In addition, NO3− deficits coincided with elevated δ15N-NO3− values and δ18O-NO3− values demonstrated the coexistence of NO3− assimilation during the typhoon period. This study suggests that the changing processes involved in NO3− cycling after typhoons and rainstorms are associated with the stability and intensity of the salinity front altered by these weather events.

SUDS: New solution for urban flooding

Climate change causing extreme weather events across the world. The excising urban drainage system facing the great stress of managing heavy precipitation events and caused urban flooding. The specialists in the urban designing field are searching for more effective way of managing flooding events. Sustainable Urban Drainage System is kind of drainage system design which simulating nature rainwater managing practices. In this research, the SUDS is analyzed mainly from three aspects: Flood managing ability, economic benefits, and ecological benefits. This research reviews the existing SUDS examples and research basing on the SUDS designing strategies. Research has found that the SUDS is more than capable of managing stormwater but also can generate both monetary and indirect economic benefit. Furthermore, the nature feature of SUDS facilities can provide ecological benefits like providing habitats for animals, improving hydrological feature, and increase comfortability for residents. Thus, SUDS can be an ideal solution for the new urban drainage systems.

Severe flood modulates the sources and age of dissolved organic carbon in the Yangtze River Estuary

Floods in global large rivers modulate the transport of dissolved organic carbon (DOC) and estuarine hydrological characteristics significantly. This study investigated the impact of a severe flood on the sources and age of DOC in the Yangtze River Estuary (YRE) in 2020. Comparing the flood period in 2020 to the non-flood period in 2017, we found that the flood enhanced the transport of young DOC to the East China Sea (ECS), resulting in significantly enriched Δ14C-DOC values. During the flood period, the proportion of modern terrestrial organic carbon (OC) was significantly higher compared to the non-flood period. Conversely, the proportion of pre-aged sediment OC was significantly lower during the flood period. The high turbidity associated with the flood facilitated rapid transformation and mineralization of sedimentary and fresh terrestrial OC, modifying the sources of DOC. The flux of modern terrestrial OC transported to the ECS during the flood period was 1.58 times higher than that of the non-flood period. These findings suggest that floods can modulate the sources and decrease the age of DOC, potentially leading to increased greenhouse gas emissions. Further research is needed to understand the long-term impacts of floods on DOC dynamics in global estuaries.

Disentangling determinants of nearshore fish and crayfish assemblages in a canyon-shaped Mediterranean reservoir

The distinct origin and hydrological characteristics of reservoirs, shaped by fluctuating water levels and seasonal variations, play a crucial role in determining aquatic species assemblages across diverse limnological zones. This study aimed to analyze fish and crayfish assemblages in the nearshore area of a canyon-shaped Mediterranean reservoir, seeking to identify seasonal and spatial convergent patterns and infer the factors influencing them. Samplings were conducted at five stations along the longitudinal profile of the reservoir at depths around 7 m using gillnets and hoops nets. A seasonal pattern emerged regarding species abundance and biomass, with higher values recorded during the warmer period. Additionally, a spatial trend was observed, indicating higher species abundance in the middle part of the reservoir and lower abundance near the dam, particularly during the colder period. Water transparency, temperature, and the distance from the dam were identified as the most significant factors affecting species assemblages in terms of abundance and biomass. This research provides valuable insights into the intricate interplay between environmental factors, seasonal changes, and the assemblages of aquatic species in a Mediterranean reservoir, contributing to our understanding of its ecological dynamics.

Distribution and Abundance of Microplastics in Underground Rivers in the South Malang Karst Area: First Evidence in Indonesia

Introduction: The presence of microplastics in the environment increases the diversity of types of pollutants in waters, including clean water sources on the surface and underground. Karst areas have unique hydrological characteristics, with cracks and fissures between the rocks that can be potential routes for the transport and accumulation of microplastics in underground river flows. In this study, we want to know the distribution and abundance of microplastics in underground rivers in the karst area of South Malang, Indonesia. Methods: Samples were collected purposively from underground river of Lowo, Banyu and Sengik. Microplastics were prepared using a diluted solvent of 30% H2SO4 and 30% H2O2. The sediment sample was dried and then filtered twice using 300-mesh size nylon filters until microplastic particles accumulated. Results and Discussion: Microplastics were detected in all water samples, with an average abundance ranging from 1.8 to 2.3 particles per liter. Fibers were the dominant microplastic type, followed by fragments and films, while the color distribution includes blue, white, red, yellow, black, green, pink, and brown. Conclusion: Microplastic contamination has been found in underground river flows in the karst area of South Malang, Indonesia. Karst soil, traditionally viewed as a natural filter, is not impervious to plastic pollution. This suggests significantly higher surface contamination than previously assumed. Therefore, reducing surface pollution is essential to safeguard the precious quality of underground aquifers and protect public health above.

City-scale modelling of road thermal and hydrologic characteristics and failure mechanisms: Case study of Montreal

This study focuses on understanding and quantifying projected changes to road thermal and hydrologic characteristics that are associated with road failure, for the City of Montreal, Canada. To this end, city-scale modelling using a land surface model with realistic representation of urban regions, including roads, enabled by the super-resolution of 250 m, for the current 2001–2020 and future 2041–2060 periods are used. Analysis for the cold season suggests potential reduction in failures associated with thermal characteristics such as daily freeze-thaw and partial thaws, with a projected decrease of 12.5% and 2 %, respectively. Higher potential for hydrologic characteristics-related failures are likely, given projected increases in road/surface runoff in the 12–15% range. For the warm season, projected increases in thermal characteristics such as daily maximum and minimum temperatures (4–4.5 °C), and hydrological characteristics (25 %), suggest increased potential for road failure from rutting and drainage issues. Analysis performed separately for the highways and local roads reveal important spatial variability of the considered characteristics and associated failures, which can be helpful in prioritizing road sections for detailed analysis and in the development of sustainable adaptation strategies for the Montreal road network and enhancing the city's resilience to future climate change.