The L-moment based regional approach to curve numbers for Slovak and Polish Carpathian catchments

AbstractThe main objective of the paper was to propose and evaluate the performance of a regional approach to estimate CN values and to test the impact of different initial abstraction ratios. The curve number (CN) was analyzed for five Slovak and five Polish catchments situated in the Carpathian Mountains. The L-moment based method of Hosking and Wallis and the ANOVA test were combined to delineate the area in two homogenous regions of catchments with similar CN values. The optimization condition enabled the choice of the initial abstraction ratio, which provided the smallest discrepancy between the tabulated and estimated CNs and the antecedent runoff conditions. The homogeneity in the CN within the regions of four Slovak and four Polish catchments was revealed. Finally, the regional CN was proposed to be at the 50% quantile of the regional theoretical distribution function estimated from all the CNs in the region.The approach is applied in a group of Slovak and Polish catchments with physiographic conditions representative for the Carpathian region. The main benefit of introducing a common regional CN is the opportunity to apply this procedure in catchments of similar soil-physiographic characteristics and to verify the existing tabulated CN. The paper could give rise to an alternative way of estimating the CN values in forested catchments and catchments with a lack of data or without observations.

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Initial abstraction ratio and Curve Number estimation using rainfall and runoff data from a tropical watershed

RBRH ◽

10.1590/2318-0331.241920170199 ◽

2019 ◽

Vol 24 ◽

Cited By ~ 2

Author(s):

Luiz Claudio Galvão do Valle Junior ◽

Dulce Buchala Bicca Rodrigues ◽

Paulo Tarso Sanches de Oliveira

Keyword(s):

Conversion Factor ◽

Poor Performance ◽

Curve Number ◽

Storm Events ◽

Rainfall Runoff ◽

Initial Abstraction ◽

Rainfall Depth ◽

Standard Value ◽

Tropical Watershed ◽

Runoff Events

ABSTRACT The Curve Number (CN) method is extensively used for predict surface runoff from storm events. However, remain some uncertainties in the method, such as in the use of an initial abstraction (λ) standard value of 0.2 and on the choice of the most suitable CN values. Here, we compute λ and CN values using rainfall and runoff data to a rural basin located in Midwestern Brazil. We used 30 observed rainfall-runoff events with rainfall depth greater than 25 mm to derive associated CN values using five statistical methods. We noted λ values ranging from 0.005 to 0.455, with a median of 0.045, suggesting the use of λ = 0.05 instead of 0.2. We found a S0.2 to S0.05 conversion factor of 2.865. We also found negative values of Nash-Sutcliffe Efficiency (to the estimated and observed runoff). Therefore, our findings indicated that the CN method was not suitable to estimate runoff in the studied basin. This poor performance suggests that the runoff mechanisms in the studied area are dominated by subsurface stormflow.

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A Daily Water Balance Model Based on the Distribution Function Unifying Probability Distributed Model and the SCS Curve Number Method

Water ◽

10.3390/w14020143 ◽

2022 ◽

Vol 14 (2) ◽

pp. 143

Author(s):

Marwan Kheimi ◽

Shokry M. Abdelaziz

Keyword(s):

Distribution Function ◽

Water Balance ◽

Soil Water ◽

Storage Tank ◽

Water Storage ◽

Curve Number ◽

Water Balance Model ◽

Balance Model ◽

Soil Water Storage ◽

Daily Water

A new daily water balance model is developed and tested in this paper. The new model has a similar model structure to the existing probability distributed rainfall runoff models (PDM), such as HyMOD. However, the model utilizes a new distribution function for soil water storage capacity, which leads to the SCS (Soil Conservation Service) curve number (CN) method when the initial soil water storage is set to zero. Therefore, the developed model is a unification of the PDM and CN methods and is called the PDM–CN model in this paper. Besides runoff modeling, the calculation of daily evaporation in the model is also dependent on the distribution function, since the spatial variability of soil water storage affects the catchment-scale evaporation. The generated runoff is partitioned into direct runoff and groundwater recharge, which are then routed through quick and slow storage tanks, respectively. Total discharge is the summation of quick flow from the quick storage tank and base flow from the slow storage tank. The new model with 5 parameters is applied to 92 catchments for simulating daily streamflow and evaporation and compared with AWMB, SACRAMENTO, and SIMHYD models. The performance of the model is slightly better than HyMOD but is not better compared with the 14-parameter model (SACRAMENTO) in the calibration, and does not perform as well in the validation period as the 7-parameter model (SIMHYD) in some areas, based on the NSE values. The linkage between the PDM–CN model and long-term water balance model is also presented, and a two-parameter mean annual water balance equation is derived from the proposed PDM–CN model.

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Land use influences stream bacterial communities in lowland tropical watersheds

Scientific Reports ◽

10.1038/s41598-021-01193-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Karina A. Chavarria ◽

Kristin Saltonstall ◽

Jorge Vinda ◽

Jorge Batista ◽

Megan Lindmark ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

Bacterial Communities ◽

Secondary Forest ◽

Stream Water ◽

Community Diversity ◽

Forested Catchments ◽

Unifrac Distance ◽

Cattle Pasture ◽

The Impact

AbstractLand use is known to affect water quality yet the impact it has on aquatic microbial communities in tropical systems is poorly understood. We used 16S metabarcoding to assess the impact of land use on bacterial communities in the water column of four streams in central Panama. Each stream was influenced by a common Neotropical land use: mature forest, secondary forest, silvopasture and traditional cattle pasture. Bacterial community diversity and composition were significantly influenced by nearby land uses. Streams bordered by forests had higher phylogenetic diversity (Faith’s PD) and similar community structure (based on weighted UniFrac distance), whereas the stream surrounded by traditional cattle pasture had lower diversity and unique bacterial communities. The silvopasture stream showed strong seasonal shifts, with communities similar to forested catchments during the wet seasons and cattle pasture during dry seasons. We demonstrate that natural forest regrowth and targeted management, such as maintaining and restoring riparian corridors, benefit stream-water microbiomes in tropical landscapes and can provide a rapid and efficient approach to balancing agricultural activities and water quality protection.

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Influence of Overheating Degree on Material Reliability of A390.0 Alloy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.191.23 ◽

2012 ◽

Vol 191 ◽

pp. 23-28 ◽

Cited By ~ 6

Author(s):

Jaroslaw Piątkowski

Keyword(s):

Tensile Strength ◽

Distribution Function ◽

Weibull Distribution ◽

Fatigue Testing ◽

Testing Machine ◽

Time To Failure ◽

The Impact ◽

Failure Evaluation ◽

Graphic Interpretation ◽

Gravity Cast

The object of the studies was A390.0 alloy (AlSi17Cu5Mg), similar to A3XX.X series, gravity cast into sand and metal moulds. This alloy is mainly used for cast pistons operating in I.C. engines, for cylinder blocks and housings of compressors, and for pumps and brakes. The A390.0 alloy was poured at temperatures 880 and 980°C, holding the melt for 30 minutes and casting from the temperature of 780°C. The assessment of the impact of the degree of overheating was to analysis the tensile strength. Studies were carried out on a normal-running fatigue testing machine, which was the mechanically driven resonant pulsator. For the needs of quantitative reliability evaluation and the time-to-failure evaluation, the procedures used in survival analysis, adapted to the analysis of failure-free operation with two-parametric Weibull distributions, were applied. Having determined the boundary value σ0 for Weibull distribution, the value of „m” modulus was computed along with other coefficients of material reliability, proposed formerly by the authors. Basing on the obtained results, a model of Weibull distribution function was developed for the tensile strength with respective graphic interpretation.

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ANN-SCS-based hybrid model in conjunction with GCM to evaluate the impact of climate change on the flow scenario of the River Subansiri

Journal of Water and Climate Change ◽

10.2166/wcc.2019.221 ◽

2019 ◽

Vol 11 (4) ◽

pp. 1150-1164

Author(s):

Swapnali Barman ◽

Rajib Kumar Bhattacharjya

Keyword(s):

Land Use ◽

Land Cover ◽

Hybrid Model ◽

Curve Number ◽

Future Trend ◽

Land Use Land Cover ◽

Ann Model ◽

Non Linear ◽

The Future ◽

The Impact

Abstract The River Subansiri, one of the largest tributaries of the Brahmaputra, makes a significant contribution towards the discharge at its confluence with the Brahmaputra. This study aims to investigate an appropriate model to predict the future flow scenario of the river Subansiri. Two models have been developed. The first model is an artificial neural network (ANN)-based rainfall-runoff model where rainfall has been considered as the input. The future rainfall of the basin is calculated using a multiple non-linear regression-based statistical downscaling technique. The proposed second model is a hybrid model developed using ANN and the Soil Conservation Service (SCS) curve number (CN) method. In this model, both rainfall and land use/land cover have been incorporated as the inputs. The ANN models were run using time series analysis and the method selected is the non-linear autoregressive model with exogenous inputs. Using Sen's slope values, the future trend of rainfall and runoff over the basin have been analyzed. The results showed that the hybrid model outperformed the simple ANN model. The ANN-SCS-based hybrid model has been run for different land use/land cover scenarios to study the future flow scenario of the River Subansiri.

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Variability of the Initial Abstraction Ratio in an Urban and an Agroforested Catchment

Water ◽

10.3390/w12020415 ◽

2020 ◽

Vol 12 (2) ◽

pp. 415 ◽

Cited By ~ 5

Author(s):

Adam Krajewski ◽

Anna E. Sikorska-Senoner ◽

Agnieszka Hejduk ◽

Leszek Hejduk

Keyword(s):

Land Use ◽

Curve Number ◽

Threshold Value ◽

Storm Events ◽

Direct Runoff ◽

Initial Abstraction ◽

Land Use Types ◽

Rainfall Depth ◽

Storm Rainfall ◽

Service Curve

The Curve Number method is one of the most commonly applied methods to describe the relationship between the direct runoff and storm rainfall depth. Due to its popularity and simplicity, it has been studied extensively. Less attention has been given to the dimensionless initial abstraction ratio, which is crucial for an accurate direct runoff estimation with the Curve Number. This ratio is most often assumed to be equal to 0.20, which was originally proposed by the method’s developers. In this work, storm events recorded in the years 2009–2017 in two small Polish catchments of different land use types (urban and agroforested) were analyzed for variability in the initial abstraction ratio across events, seasons, and land use type. Our results showed that: (i) estimated initial abstraction ratios varied between storm events and seasons, and were most often lower than the original value of 0.20; (ii) for large events, the initial abstraction ratio in the catchment approaches a constant value after the rainfall depth exceeds a certain threshold value. Thus, when using the Soil Conservation Service-Curve Number (SCS-CN) method, the initial abstraction ratio should be locally verified, and the conditions for the application of the suggested value of 0.20 should be established.

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Probing the strange content of the proton with charm production in charged current at LHeC

The European Physical Journal C ◽

10.1140/epjc/s10052-019-7362-7 ◽

2019 ◽

Vol 79 (10) ◽

Author(s):

Hamed Abdolmaleki ◽

◽

Valerio Bertone ◽

Daniel Britzger ◽

Stefano Camarda ◽

...

Keyword(s):

Distribution Function ◽

Strange Quark ◽

Parton Distribution Function ◽

Charm Production ◽

Charged Current ◽

Kinematic Range ◽

Multi Scale ◽

Potential Improvement ◽

The Impact

Abstract We study charm production in charged-current deep-inelastic scattering (DIS) using the xFitter framework. Recent results from the LHC have focused renewed attention on the determination of the strange-quark parton distribution function (PDF), and the DIS charm process provides important complementary constraints on this quantity. We examine the current PDF uncertainty and use LHeC pseudodata to estimate the potential improvement from this proposed facility. As xFitter implements both fixed-flavor- and variable-flavor-number schemes, we can compare the impact of these different theoretical choices; this highlights some interesting aspects of multi-scale calculations. We find that the high-statistics LHeC data covering a wide kinematic range could substantially reduce the strange PDF uncertainty.

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Optimized Process Parameters for a Reproducible Distribution of Relaxation Times Analysis of Electrochemical Systems

Batteries ◽

10.3390/batteries5020043 ◽

2019 ◽

Vol 5 (2) ◽

pp. 43 ◽

Cited By ~ 14

Author(s):

Markus Hahn ◽

Stefan Schindler ◽

Lisa-Charlotte Triebs ◽

Michael A. Danzer

Keyword(s):

Distribution Function ◽

Electrochemical Impedance ◽

Regularization Parameter ◽

Relaxation Times ◽

Measurement Data ◽

Complex Impedance ◽

Lithium Ion ◽

Parameter Study ◽

Model Free ◽

The Impact

The distribution of relaxation times (DRT) analysis offers a model-free approach for a detailed investigation of electrochemical impedance spectra. Typically, the calculation of the distribution function is an ill-posed problem requiring regularization methods which are strongly parameter-dependent. Before statements on measurement data can be made, a process parameter study is crucial for analyzing the impact of the individual parameters on the distribution function. The optimal regularization parameter is determined together with the number of discrete time constants. Furthermore, the regularization term is investigated with respect to its mathematical background. It is revealed that the algorithm and its handling of constraints and the optimization function significantly determine the result of the DRT calculation. With optimized parameters, detailed information on the investigated system can be obtained. As an example of a complex impedance spectrum, a commercial Nickel–Manganese–Cobalt–Oxide (NMC) lithium-ion pouch cell is investigated. The DRT allows the investigation of the SOC dependency of the charge transfer reactions, solid electrolyte interphase (SEI) and the solid state diffusion of both anode and cathode. For the quantification of the single polarization contributions, a peak analysis algorithm based on Gaussian distribution curves is presented and applied.

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Bootstrap-current computations for a stellarator-reactor plasma

Journal of Plasma Physics ◽

10.1017/s0022377800015294 ◽

1990 ◽

Vol 44 (3) ◽

pp. 431-453 ◽

Cited By ~ 2

Author(s):

W. D. D'Haeseleer ◽

W. N. G. Hitchon ◽

C. D. Beidler ◽

J. L. Shohet

Keyword(s):

Distribution Function ◽

Kinetic Equation ◽

Physical Interpretation ◽

Collision Operator ◽

Numerical Code ◽

Parallel Flows ◽

Bootstrap Current ◽

The Difference ◽

Rotational Transform ◽

The Impact

Numerical results for the bootstrap current in a stellarator-reactor plasma are presented. The distribution function f is computed numerically from a kinetic equation that is averaged over the helical ripple. The parallel flows and the current are obtained as v‖ moments of f. The physics issues embedded in the code are discussed concisely, concentrating on the justification as to why the bootstrap current can be estimated from an averaged scheme. Results are presented for typical stellarator-reactor parameters. The numerical code FLOCS predicts that the momentum-restoring terms in the collision operator have no significant impact on the value of the bootstrap current (the difference being about 10%). The results obtained are related to the equilibrium flows, and a physical interpretation based on the kinetic picture is presented. Finally, an estimate for the impact of J‖ on the rotational transform is given.

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