rss_2.0Sciendo RSS Feed for Journal of Hydrology and Hydromechanicshttps://sciendo.com/journal/JOHHhttps://www.sciendo.comhttps://sciendo-parsed.s3.eu-central-1.amazonaws.com/647223c9215d2f6c89dbd2cb/cover-image.jpghttps://sciendo.com/journal/JOHH140216https://sciendo.com/article/10.2478/johh-2024-0013<abstract> <title style='display:none'>Abstract</title> <p>Novel soil datasets and the application of pedotransfer functions provide soil hydraulic input data for modelling hydrological processes at different scales. We aimed to evaluate the reliability of soil hydraulic parameters derived by indirect methods in simulation of soil moisture time series and water budgets at profile level of three sites (Forest, Orchard and Grassland) from a Central European catchment (Lake Balaton, Hungary). Five soil-vegetation-atmosphere model variants were set up with the Hydrus-1D model for each site, differing only in the parametrization of input soil data: i) a calibrated reference, ii) measured values, iii) values predicted from measured basic soil properties, iv) values predicted from national soil map information, v) values derived from the 3D soil hydraulic dataset of Europe. Calibrated soil parameters led to Nash-Sutcliffe efficiency 0.50, 0.54 and 0.71 for the Forest, Orchard and Grassland Site respectively. The outcomes for model efficiency of soil moisture underline the superiority of local databases over regional ones and the need for more detailed vertical discretization during modelling. The model performance according to soil moisture and water budget accuracy led to different rank order of model variants. Water budget comparisons indicated moderate differences between the hydrologic fluxes simulated by the different model variants, emphasizing the uncertainties associated with soil hydraulic parametrization either at local or at watershed scale.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00132024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0014<abstract> <title style='display:none'>Abstract</title> <p>This study explores how the ice cover on water surfaces affects the deformation of the channel bed around non-submerged spur dikes. Laboratory experiments have been conducted by using two types of model ice cover with different roughness coefficients and three sands with different median grain sizes. The effects of various layout angles of non-submerged spur dikes on the maximum scour depth and scour patterns around spur dikes have been evaluated. Results showed that the dike orientation angle is the critical factor influencing the maximum scour depth. The presence of an ice cover and its roughness coefficient dramatically affect the channel bed deformation around spur dikes. The combined effect of the dike orientation angle, ice cover roughness, and flow Froude number resulted in different scour patterns. For instance, the upstream length of scour holes decreases by approximately 60% when the dike angle changes from 90º to 60º, while an increase in flow rate by about 50% leads to a 20% increase in the downstream length of scour holes. Equations have been derived to determine the maximum scour depth around spur dikes, considering the effects of ice cover, bed material and the dike layout angles.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00142024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0011<abstract> <title style='display:none'>Abstract</title> <p>The construction and operation of waterworks has a significant impact on natural ecosystems. The evaluation of their negative impact and the proposal to minimize their impact, as well as the revitalization, especially of large rivers, have been given great importance in recent decades. The main goal of the study is to present impact of Gabčíkovo Waterwork on forest ecosystems after 30 years of damming. Specially evaluated are monitoring sites where changes are observed in the Slovak part of the so-called inland delta, i.e., between old and new riverbed of the Danube. The assessment of changes in terrestrial vegetation on selected monitoring sites was compared with the assessment of parallel measured soil moisture data. At the same time, data from the National Forestry Centre were also used to monitor changes in the state of forest ecosystems in the whole area of interest.</p> <p>When comparing the species composition from state to 2015 and from the period before GW was put into operation (in 1990) an increase was found in the area share of hardwood floodplain forest by 5.77% and the area shares of softwood floodplain forests decreased by 1.71%. Between 1990 and 2015, 68.43% of the territory remained unchanged at the level of forest type groups. A change in habitat conditions towards drier forest types was recorded on 23.61% of the territory.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00112024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0015<abstract> <title style='display:none'>Abstract</title> <p>Studies across multiple soils find increasing pH decreases water repellency. In this study, water repellency and a range of other soil physical properties of bulk soils, aggregates and intact specimens were measured on a long-term pH field experiment on a single sandy loam soil under a ley-arable crop rotation, with soil pH adjustments occurring annually by adding FeSO₄ or CaCO₃, to lower or raise the pH, respectively. Crop impacts were investigated by comparing 3rd year grass-white clover to spring oats, at the beginning (May) and end (September) of the growing season to allow soil structure comparisons. As in previous research, increased CO₂ microbial respiration (<italic>p</italic>&lt;0.05) was found with increasing pH along the gradient, but in this study, we found only the aggregate and soil bulk density affected by soil pH. Soil-water contact angles differed between crops (<italic>p</italic>&lt;0.05), as well as the repellency index of soil aggregates, however, there was no soil pH effect. Overall, differences in data were found to be a result of the various crops in the rotation rather than by soil pH, indicating only minor impacts on soil physical characteristics after &gt; 55 years of chemical additions to amend soil pH.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00152024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0012<abstract> <title style='display:none'>Abstract</title> <p>Proper characterization of the unsaturated hydraulic properties in rocks is significant for predicting fluid flow in soil, hydrogeologic, and petroleum science and engineering problems. In this study, we contributed rigorous analysis of the unsaturated hydraulic properties of three reservoir rock samples (Berea Sandstone, Guelph Dolomite, and Indiana Limestone). An improved version of the standard evaporation method (HYPROP) was developed to cater specifically to rock samples. The improved HYPROP setup enables measurements of local water pressures within rock samples without disturbing the upper portion of the samples. The obtained results were compared with those obtained using the conventional pressure plate method and a state-of-the-art nuclear magnetic resonance (NMR) method. Observed data were analyzed in terms of four different unimodal and bimodal hydraulic functions. The HYPROP data were found to be relatively close to the pressure plate data of two carbonate rocks. The NMR-based data were reasonably consistent with the HYPROP data, with differences likely due in part to the fact that they were obtained using two different 5-cm long plugs taken from the same core. Heterogeneity along the rock cores from which the samples were taken could be a major reason for the observed differences, and hence should be considered in reservoir analyses.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00122024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0018<abstract> <title style='display:none'>Abstract</title> <p>This paper presents an experimental and numerical study of the freezing-thawing behavior of water in fully saturated sand. A relatively inexpensive and easily replicable experimental procedure was developed to simulate the freezing-thawing cycles in a medium-sized sand sample placed in a modified commercial freezer. By insulating the sides and bottom of the sample well, while allowing good thermal conductivity at the top of the sample, a nearly vertical advance of the freezing and thawing front was achieved. A series of freeze-thaw cycles were performed with higher and lower temperature gradients. A numerical multiphysics model, assuming an axially symmetric geometry based on the transient heat transfer during the phase transition, used a parametric approach to estimate the effective thermal properties of the sand-water-ice system. A good agreement between experimental and modelling results was shown, but slightly different parameter sets were obtained for each temperature gradient. The presented method could be a simple way to characterize the freeze-thaw process in natural and artificial porous materials.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00182024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0017<abstract> <title style='display:none'>Abstract</title> <p>Soil erosion is a complex and highly heterogeneous process with a wide range of environmental and economic impacts. Its estimation is particularly challenging and modelling is typically used for erosion estimation over large areas. The aim of this study was to compare the two leading empirical and physical erosion estimation models, i.e. the Revised Universal Soil Loss Equation (RUSLE) and the Water Erosion Prediction Project (WEPP). The models were calibrated and validated using data collected from field experiments conducted in agricultural lands of Mexico. The simulated rainfall experiments involved measuring erosion from field plots subjected to four tillage systems (No crop, Conventional tillage, Conventional tillage + residues, and Handspike) under two antecedent soil moisture conditions (dry and wet). Different calibration approaches based on the factors K and C for RUSLE, and interrill erodibility and hydraulic conductivity in WEPP were tested. The best-performing methods in RUSLE involved measuring the K factor and adopting the recommended C factor by the National Forestry Commission of Mexico. In WEPP, the best results were obtained when interrill erodibility was estimated from experimental measurements. Overall, RUSLE outperformed WEPP in most of the treatments except for CT under WAMC.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00172024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0019<abstract> <title style='display:none'>Abstract</title> <p>River bank protection is vital in hydraulic river engineering to preserve natural rivers, lands, and critical constructions such as bridges. Spur dikes are erosion-protective structures that protrude outward from the river bank in different orientations to deflect the flow away from the riverbank. The present experimental study provides insight into the temporal variation in bed morphology and scours around rectangular-shaped spur dikes with different orientations, such as 60º, 90º, and 120º. Also, maximum scour depth (MSD) is developed compared to the condition when downward seepage is applied. The experiments examined the suitability of various spur dike orientation configurations and the scour development over time, specifically at intervals of 2, 12, and 24 hours, and compared with 24 hours (Seepage). Results showed that the orientation angle of 90º generated the highest scour depth, while the least scour depth was found with an orientation angle of 120º. The downward seepage intensifies the motion of sediment particles and leads to an escalated particle detachment, resulting in deeper scour depressions. The development of scour depth is initiated from the spur dike tip and reaches its maximum there. The deposition of sand particles shifted downstream, and a dune-like structure formed near the second spur dike.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00192024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0016<abstract> <title style='display:none'>Abstract</title> <p>The Groundwater Ubiquity Score (GUS) is widely used to indicate the relative leachability of pesticides based on the soil half-life and the adsorption partition coefficient. In this manuscript, we derive mathematically the Theoretical Groundwater Ubiquity Score (TGUS) that, based on considerations of the preferential movement of pesticides to groundwater and a first-order pesticide degradation model, leads to a similar function as the GUS model. In the preferential flow model, movement to groundwater is fast, and the adsorption partition coefficient is thus not used for calculating the travel time to the groundwater (as it is in the advective-dispersive equation) but rather only determines the distribution of the pesticide between the water and soil phases. Both the GUS and TGUS models well predict the groundwater contamination of the originally studied pesticides for rainfall event(s) that caused pesticide leaching from 30 days after application. The theoretically derived Groundwater Ubiquity Score (TGUS) shows, in accordance with experimental evidence, that for leaching events shortly after spraying, the mass lost to (and resulting concentration in) groundwater is inversely related to the adsorption partition coefficient and not necessarily to the GUS index.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00162024-08-15T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0009<abstract> <title style='display:none'>Abstract</title> <p>Soil erosion monitoring is essential for the ecological evaluation and dynamic monitoring of land resources via remote sensing technology. In this paper, we provide new insights into the existing problems and development directions of traditional models, which are supported by new technologies. An important role is played by remote sensing information acquisition technology in the qualitative and quantitative evaluation of soil erosion, and the data and technical support provided are systematically reviewed. We provide a detailed overview of the research progress associated with empirical statistical models and physically driven process models of soil erosion, and the limitations of their application are also summarized. The preliminary integration of remote sensing data sources with high spatial and temporal resolution and new technologies for soil erosion monitoring enables the high-precision quantitative estimation of sediment transport trajectories, the watershed river network density, and the terrain slope, enhancing the accuracy of erosion factor identification, such as spectral feature recognition from erosion information, gully erosion feature extraction, and vegetation coverage estimation. However, the current erosion models, driven by algorithms and models, are not comprehensive enough, particularly in terms of the spatial feature extraction of erosion information, and there are limitations in the applicability and accurate estimation of such models.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00092024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0004<abstract> <title style='display:none'>Abstract</title> <p>Climate change can have a profound impact on river flooding, leading to increased frequency and severity of floods. To mitigate these effects, it is crucial to focus on enhancing early warning systems and bolstering infrastructure resilience through improved forecasting. This proactive approach enables communities to better plan for and respond to flood events, thereby minimizing the adverse consequences of climate change on river floods. During river flooding, the channels often take on a compound nature, with varying geometries along the flow length. This complexity arises from construction and agricultural activities along the floodplains, resulting in converging, diverging, or skewed compound channels. Modelling the flow in these channels requires consideration of additional momentum transfer factors. In this study, machine learning techniques, including Gene Expression Programming (GEP), Artificial Neural Networks (ANN), and Support Vector Machines (SVM), were employed. The focus was on a compound channel with converging floodplains, predicting the shear force carried by the floodplains in terms of non-dimensional flow and hydraulic parameters. The findings indicate that the proposed ANN model outperformed GEP, SVM, and other established approaches in accurately predicting floodplain shear force. This research underscores the efficacy of utilizing machine learning techniques in the examination of river hydraulics.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00042024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0008<abstract> <title style='display:none'>Abstract</title> <p>The article deals with the determination of the influence of the relative width of an approach channel with a rectangular cross-section on the discharge of clean water flowing over thin-plated weirs with a triangular notch and zero height of the weir above the bottom of the approach channel. To evaluate the influence, the Kindsvater-Shen equation was modified by introducing the basic effective discharge coefficient and the coefficient of the relative width of the approach channel. The coefficient of the relative width of the approach channel was determined based on the evaluation of data from three extensive experimental research investigations. It is valid for the entire possible range of relative widths of the approach channel and for the range of notch angles from 5.25° to 91.17°. The relative error of discharge determination is approximately up to ±2% over the entire range of discharges used in the conducted experimental research. The evaluation made it possible to determine the boundary distinguishing the partially contracted weirs from the fully contracted weirs in terms of impact on discharge.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00082024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0005<abstract> <title style='display:none'>Abstract</title> <p>Due to the increased number of forest fires, a detailed examination and knowledge of the effects of the microclimatic conditions of forests is currently significant. The study carried out in Arboretum Borova hora (Slovak Republik), investigates the influence of meteorological factors (air temperature, relative humidity), the value of the Angström index, and the danger class of the Angström index on the moisture content of fine fuel at the edge of a beech forest stand, but also in its interior. We tested three working hypotheses: a) meteorological conditions differ significantly between the edge and the interior of the beech forest, b) the moisture content of fine fuel is higher in the beech forest interior than at the forest edge, c) the Angström index fire danger class is higher at the edge of the beech forest than in its interior. We created a calibration curve that was also used to measure the humidity of beech leaves with the help of the ME 2000 hygrometer. Our results show that edge beech stands are significantly more susceptible to fires, lower air humidity and fine fuel moisture content, and higher air temperatures than forest interiors. From our point of view, the microclimate is considered the main factor that explains the difference between the vegetation structure of the forest edge and the forest interior.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00052024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0010<abstract> <title style='display:none'>Abstract</title> <p>Enhanced understanding of flow resistance in open channels with emergent vegetation is essential for flood management and river ecosystem restoration. The presence of vegetation can significantly alter bed resistance, leading to a challenge in accurately predicting flow discharge, water levels, sediment transport, and bed deformation. Previous studies on vegetated flows have focused on vegetation resistance, on which the impact of vegetation has been ignored or poorly estimated. This study proposes a new analytical model, built upon the momentum conservation law, to predict flow resistance to vegetated zones in a plain bed without bed forms, explicitly quantifying bed resistance and vegetation resistance in a corollary manner. The proposed model is benchmarked against five typical sets of laboratory experiments. It is demonstrated that the present model using a modified logarithmic velocity distribution performs best, whereas that assuming a uniform velocity profile considerably overestimates the vegetation resistance and neglects the effect of vegetation on bed resistance. The ratio of bed resistance to the total resistance is shown to range between 5% and 40%, and it decreases with increasing vegetation density and decreases with water depth. Therefore, bed resistance cannot be ignored when modelling shallow water flow with sparsely distributed vegetation. It is also revealed that vegetation arrangements significantly affect flow resistance, and therefore a model incorporating the effect of vegetation arrangement performs better. Overall, the present model facilitates a viable and promising tool for quantifying flow resistance in emergent vegetated channels.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00102024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0006<abstract> <title style='display:none'>Abstract</title> <p>According to many authors, hydrological modelling is one of the fundamental techniques for determining the impacts of various environmental changes on the quantitative characteristics of the aquatic environment. This study examines the effects of landscape changes induced by the need to respond to climate change and the natural urban development of the rural setting on the discharge from the small catchment. The SWAT model was applied to a small catchment of Kopaninsky Stream in the traditional agricultural part of the Czech Republic. According to the results, the most effective approach for reducing the consequences of hydrological extremes in the catchment and retaining more water in the landscape is the properly spaced placement of grassland and forest enclaves in the developing urban structure. In practice, each land use category’s overall percentage of representation is less significant than its relative arrangement.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00062024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0001<abstract> <title style='display:none'>Abstract</title> <p>Layered soils can consist of a thin little permeable upper layer over a more permeable subsoil. There are not many experimental data on the influence of this upper layer on infiltration. The mini-disk infiltrometer set at a pressure head of –3 cm was used to compare infiltration of nearly 40 mm of water in homogeneous loam and clay soil columns with that in columns made by a thin layer (1 and 3 cm) of clay soil over the loam soil. For each run, the Horton infiltration model was fitted to the data and the soil sorptivity was also estimated by considering the complete infiltration run. For the two layered soils, the estimates of initial infiltration rate and decay constant were similar but a thicker upper layer induced 2.4 times smaller final infiltration rates. Depending on the infiltration parameter and the thickness of the upper layer, the layered soils were characterized by 2.2–6.3 times smaller values than the loam soil and 2.2–6.6 higher values than the clay soil. Sorptivity did not differ between the homogeneous clay soil and the layered soil with a thick upper layer and a thin layer was enough to induce a decrease of this hydrodynamic parameter by 2.5 times as compared with that of the homogeneous loam soil. Even a thin upper layer influences appreciably infiltration and hydrodynamic parameters. Layering effects vary with the thickness of the upper layer and the considered parameter. The applied experimental methodology could be used with other soils and soil combinations.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00012024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0003<abstract> <title style='display:none'>Abstract</title> <p>The study aims to presents flow heterogeneity over rough permeable and impermeable gravel-bed stream. The rough permeable stream is prepared by laying multiple layers of gravel, whereas its impermeable counterpart is presented by a resin-casted gravel-bed. In general, a common approach can be found in literature to mimic an impermeable bed by laying single layer of gravels, therefore some results are compared with single layer gravel-bed stream keeping the hydraulic conditions same. An acoustic Doppler velocimeter was used for flow measurements whereas; double averaging (DA) methodology was adopted for data analysis. The larger flow penetration depth and intense flow mixing in permeable gravel-bed infer sufficient impetus for organized flow turbulence and damping of DA Reynolds shear stresses whereas; the wall-blocking in resin-casted gravel-bed prevents fluid infiltration which leads to follow the linear stress profile away from the crest level. The damping of DA Reynolds shear stress (RSS) is compensated by enhanced DA form-induced shear stress (FISS). The results are further analysed under the light of the energy budget to characterize the mass-momentum exchange as it penetrates the subsurface layers. The energy budget indicates negative pressure energy diffusion rates corroborating gain in turbulence production in the permeable gravel-bed stream.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00032024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0002<abstract> <title style='display:none'>Abstract</title> <p>In this study, the influence of riverbed silting on the groundwater regime in a lowland area was investigated. The study area is situated at the Rye Island (Žitný Ostrov) in Slovakia, along the Gabčíkovo – Topoľníky canal, which is part of the drainage-irrigation canal system constructed in this locality. The Rye Island is an area with very low slope (0.25 10^–4) and good climatic conditions for aquatic vegetation, therefore the canals are influenced by intensive silting processes. The spatial and temporal patterns of surface water – groundwater exchange are significantly influenced by the thickness of riverbed sediments and their permeability. The aim of this study was to evaluate the thickness and hydraulic conductivity of bed sediments in the Gabčíkovo – Topoľníky canal and to examine their influence on the groundwater – surface water interaction in the area. The hydraulic conductivity of the sediments was assessed from undisturbed samples by the falling head method. The obtained data were used for numerical simulations of groundwater heads by the TRIWACO model for different drainage and infiltration resistance conditions in the area of interest. The results of this study can support the planning of canal maintenance.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00022024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2024-0007<abstract> <title style='display:none'>Abstract</title> <p>Coastal wetlands are transitional ecosystems between land and sea. Participants of citizen science programs have detected frequent floods in wetlands, as well as small pools that appear and then disappear. Considering that it is not clear whether their main hydrologic drivers are of marine or continental origin, we studied the El Culebrón wetland located in the Chilean semi-arid zone. El Culebrón is strongly influenced by extreme rain events. This wetland also experiences seasonal changes in its water stage (WS). A high mean sea level agreed with 41% of the WS rises. High intensity storm surges coincided with 53% of WS peaks. A small tsunami in 2022 impacted the WS, and another very intense tsunami flooded it in 2015. An apparent diurnal cycle in the WS was discarded due to an instrumental artifact. The combination of the aforementioned factors provided an explanation for 91% of the WS rises. The probable and novel mechanism for sea level and storm surge influence on WS is the formation of a sand barrier between the coastal lagoon and the sea. As a whole, El Culebrón receives varied influences from both the sea and the mainland, but it seems to be more dependent on freshwater sources.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2024-00072024-05-09T00:00:00.000+00:00https://sciendo.com/article/10.2478/johh-2023-0044<abstract> <title style='display:none'>Abstract</title> <p>This study investigates the performance of two lumped hydrological models, BILAN and GR2M, in simulating runoff across six catchments in the Gambia River Basin (Senegal) over a 30-year period employing a 7-year sliding window under different climatic conditions. The results revealed differences in overall performance and variable sensitivity of the models to hydrological conditions and calibration period lengths, stemming from their different structure and complexity. In particular, the BILAN model, which is based on a more complex set of parameters, showed better overall results in simulating dry conditions, while the GR2M model had superior performance in wet conditions. The study emphasized the importance of the length of the calibration period on model performance and on the reduction of uncertainty in the results. Extended calibration periods for both models narrowed the range of the Kling-Gupta Efficiency (KGE) values and reduced the loss of performance during the parameter transfer from calibration to validation. For the BILAN model, a longer calibration period also significantly reduced the variability of performance metric values. Conversely, for the GR2M model, the variability rate did not decrease with the length of the calibration periods. Testing both models under variable conditions underscored the crucial role of comprehending model structure, hydrological sensitivity, and calibration strategy effects on simulation accuracy and uncertainty for reliable results.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/johh-2023-00442024-02-08T00:00:00.000+00:00en-us-1