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Sediment is a universal issue that generated in the river catchment and affects the river flow, reservoir capacity, hydropower generation and dam structure. This paper aims to present the result of experimentation in sediment load estimation using various machine learning algorithms as a powerful AI approach. The data was collected from eight locations in upstream area of Ringlet reservoir catchment. The input variables are discharge and suspended solid. It is found that there is strong correlation between sediment and suspended solid with correlation coefficient of R=0.9. The developed ML model successfully estimate the sediment load with competitive results from ANN, Decision Tree, AdaBoost and SVM. The best result is produced by SVM (ν-SVM version) where very low RMSE is generated for both training and testing dataset despite its more complicated hyperparameters setup. The results also show a promising application of machine learning for future prediction in hydro-informatic systems.

Humanity has always been closely linked to rivers, benefiting from their resources while producing impacts associated with their activity.Thus, river systems have been exposed to multiple stressors, which have affected the quality of water and their biological communities, such as those attached to substrata (biofilms) or those that are suspended in water (phytoplankton). On the other hand, biological communities also respond and contribute to the transformation and/or degradation of certain anthropogenic organic compounds, such as pharmaceuticals. This thesis investigates the chemical state of the river systems and their impacts on the biological communities, using different approaches and scales La humanitat ha estat sempre íntimament lligada als rius, beneficiant-se dels seus recursos però també produint impactes vinculats a la seva activitat. Així doncs, els sistemes fluvials han estat exposats a múltiples estressos, que han afectat la qualitat de l’aigua així com a l’ecosistema de les seves comunitats biològiques, com les adherides al biofilm o bé les que estan en suspensió a l’aigua, com el fitoplàncton. A més, les comunitats biològiques també responen i contribueixen a la transformació i/o degradació d’alguns compostos orgànics d’origen antropogènic, com els fàrmacs. Aquesta tesi investiga l’estat químic dels sistemes fluvials, i els seus impactes, utilitzant diferents aproximacions i escales La realització d’aquesta tesi no hagués estat possible sense el suport econòmic dels projectes SCARCE [Consolider-Ingenio CSD2009-00065] i GLOBAQUA [Grant Agreement No. 603629]

This paper aims to make a social and environmental assessment through the Rapid Assessment Protocols (RAP) method, in the low course of the Reis Magos river basin and in the Jacaraípe river mouth. To this end, bibliographic readings were developed about the main theories approached here, such as river systems. In addition, a PAR was made for the visual assessment of the above bodies of water with fourteen questions to be evaluated and analyzed, which involve natural and social characteristics around these rivers. The results were satisfactory, as it allowed us to infer a series of considerations about the evaluated rivers and, thus, produce scientific material that can collaborate with the governing bodies and society in urban and environmental planning. Este trabalho objetiva fazer uma avaliação socioambiental por meio do método dos Protocolos de Avaliação Rápida (PAR), no baixo curso da bacia hidrográfica do Rio Reis Magos e na foz do Rio Jacaraípe. Para tanto, foram desenvolvidas leituras bibliográficas acerca das principais teorias aqui abordadas, a exemplo dos sistemas fluviais. Além disso, foi confeccionado um PAR para a avaliação visual dos corpos d’água supracitados com quatorze questões a serem avaliadas e analisadas, das quais envolvem características naturais e sociais em torno desses rios. Os resultados foram satisfatórios, pois permitiram inferir uma série de considerações sobre os rios avaliados e, assim, produzir material científico que possa colaborar com os órgãos gestores e a sociedade nos planejamentos urbano e ambiental.

International audience; The behavior and impact of trace metals discharged into rivers depend on their solid/liquid fractionation and the fate of these two phases according to hydro-sedimentary processes. The solid/liquid fractionation depends on many environmental factors which imply uncertainties of several orders of magnitude in the evaluation of the partition coefficients, whether by geochemical modelling, in situ measurements or sorption-desorption experiments. In this context, this paper presents a model of solid/liquid fractionation of trace metals with suspended sediments in rivers which integrates the hydro-sedimentary conditions and the properties of the watershed. Its comparison with the 137Cs concentrations measured in the Rhône River (France) thanks to monitoring shows that the solid/liquid fractionation of 137Cs with suspended sediments in rivers depends on chemical processes but also and above all on variations in water flow rate, size and load of suspended sediments and the balance between anthropogenic discharges and the average trace metal content of soils in the watershed.

In ungauged catchments, flood hydrographs are usually simulated/reconstructed by simple rainfall-runoff and routing models. Horton’s and Schumm’s ratios serve as the input data for many of these models. In this paper, more than 800 Carpathian catchments (up to 35.2 km2 in area) were investigated in context of the “Horton’s and Schumm’s laws”. Results reveal that the “law of stream number” and “law of stream areas” are fulfilled in almost all catchments. The mean that values of the bifurcation ratio (RB) and the area ratio (RA) reach 3.8 and 4.8, respectively, and are thus comparable to values reported in other regions of the world. However, the “law of stream lengths” is not fulfilled in more than half of the catchments, which is not consistent with many theoretical studies reported in the literature. Only 383 (48%) catchments fulfill the “law of stream length”, with the mean value of the length ratio (RL)=2.3. There was no relationship found between the geological/geomorphological settings that influence river system development and the spatial distribution of catchments where the “law of stream length” was or was not was fulfilled. A similar conclusion was reached for the spatial distribution of the RB, RL, and RA ratios. These results confirmed that the use of Horton’s and Schumm’s ratios for the evaluation of the influence of geological/geomorphological settings on the river system development is limited. Among the lumped hydrological models, those requiring the RB, RL, and RA ratios have been extensively studied over last decades. This study suggests that the application of these models may be limited in small catchment areas; therefore, more attention should be placed on the development of hydrological models where the RB, RL, and RA ratios are not necessary.

Although many recent studies have quantified the potential effects of climate change on water resource systems, the scientific community faces now the challenge of developing methods for assessing and selecting climate change adaptation options. This paper presents a method for assessing impacts and adaptation strategies to global change in a river basin system at different temporal horizons using a hydro-economic model. First, a multiobjective analysis selects climate change projections based on the fitting of the climate models to the historical conditions for the historical period. Inflows for climate change scenarios are generated using calibrated rainfall-runoff models, perturbing observed meteorological time series according to the projected anomalies in mean and standard deviation. Demands are projected for the different scenarios and characterized using economic demand curves. With the new water resource and demand scenarios, the impact of global change on system performance is assessed using a hydro-economic model with reliability and economic indices. A new economic loss index is defined to assess the economic equity of the system. Selected adaptation strategies are simulated to compare performance with the business-as-usual scenario. The approach is applied to the Jucar River water resource system, in eastern Spain, using climate projections from the European Union (EU) ENSEMBLES project. Results show that the system is vulnerable to global change, especially over the long term, and that adaptation actions can save €3–65 million/year., Water Policy Center, Public Policy Institute of California, Estados Unidos, Instituto Universitario de Investigación de Ingeniería del Agua y Medio Ambiente, Universitat Politècnica de València, España, Unidad de Granada, Instituto Geológico y Minero de España, España

This study is focussed on a comprehensive investigation on the state of pollution of Danube and Sava rivers in Belgrade region. Different complementary analytical approaches have been used covering both (i) organic ccontaminants in river water by target analyses of hormones and neonicotinoids as well as non-target screening analyses and (ii) heavy metals in sediments. Finally, some common water quality parameters have been analysed. The overall state of pollution is on a moderate level. Bulk parameters did not reveal any unusual observation. Also quantification of preselected organic contaminants did not point to elevated pollution. A more significant contamination was measured for chromium, nickel, zinc and partially copper in sediments with values above target values according to Serbian regulations. Lastly, non-target screening analysis revealed a wider spectrum of organic contaminants comprising pharmaceuticals, technical additives, personal care products and pesticides. The study presented a comprehensive view on the state of pollution of Sava and Danube rivers and is the base for setting up further monitoring programs. As a superior outcome it has been illustrated how different chemical analyses can point to different assessments of the river quality. The comparison of target and non-target analyses pointed to potential misinterpretation of the real state of pollution.

A risk-based safety approach is indispensable to support decision-making on flood protection strategies and measures. In most deltaic areas, flood risk analysis involves more than analysing the flood hazard and the potential damage, and flood defence systems also play an important role. In such systems consisting of rivers, estuaries and flood defences, interaction effects between local failures and hydraulic loadings and reliability elsewhere in the system can be significant. Hitherto, such system behaviour has been paid little attention in flood risk analysis approaches. This paper presents a computational framework for analysing flood risk while fully accounting for system behaviour. The approach is based on Monte Carlo sampling, in which the number of computationally expensive hydrodynamic model runs is reduced significantly to only those realisations, for which the flood defence system fails. A case study illustrates the approach and demonstrates that fully accounting for system behaviour can make a significant difference for both, reliability of flood defence structures and flood risk in terms of individual risk to life as well as economic damage.

The river system of Lepenica was drawn by using the GeoMedia programme in projections of 1:25 000, 1:50 000 and 1:300 000. Different type of information was shown using each of these projections, because smaller projections show more general information, and vice versa. Using the Horton, Strahler and Schrewe Methods we were able to divide rivers into types according to their sizes. We are also able to show the density of river network as well as their physio-geographical characteristics due to their dependence on each other. Big influence on the current appearance of the river network is due to one of the physio-geographic factors called geology. Geological composition of the Lepenica flow is very convoluted. This convolution is mainly based on their origin but it’s also stratigraphical. Based on the division of rivers into their types we are able to calculate the number of watercourses, based on the Schrewe Method. Using this method we can also make conclusions with regards to density of river network. Placing the rivers into different classes is mainly used as the basis of watercourse comparisons. These methods are not only used in hydrology, but also in many other scientific areas. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Istraživanje klimatskih promena na životnu sredinu - praćenje uticaja, adaptacija i ublažavanje]

δ13C and δ15N values in suspended matter were used to examine the seasonal (late summer 2004 and spring 2005) relationship with hydrological characteristics of the River Sava watershed in Slovenia. d13C values range from - 29.2 to - 23.0 ‰ and δ15N values from 0.5 to 16.7 ‰ and indicate that the samples are a mixture of two end members: modern soils and plant litter. A simple mixing model was used to indicate that soil organic carbon prevails over plantlitter and contributes more than 50 % of suspended material. The total suspended solid flux (TSS) is estimated to be 1.3 × 1012 g/year. Anthropogenic impact was detected only in a tributary stream of the River Sava which is located in an agriculture-industrial area and is reflected in higher δ15N values in suspended matter in the late summer season.

Over the last decade several computational models, and several types of model, have been developed to simulate the response of river systems to environmental change over time scales of decades to millennia: hydrological models, flood inundation models, channel morphology models, channel network models, models of river meandering and river braiding, alluvial stratigraphy models, and landscape evolution models. Each type of model simulates different aspects of a river's response to changes in environmental inputs such as climate and land-use — and to changes in these inputs. And each type of model has its abilities, advantages and limitations. We provide an overview of the different types of model that have been developed, and we evaluate their suitability for testing hypotheses about past environmental conditions, as well as for investigating the response of alluvial river systems to future environmental change. Additionally, we discuss the general issues and problems of computational modelling (e.g. scale and resolution, data availability, process representation, process parameterization, model calibration, non-linearity, and uncertainty), and the extent to which these hamper the usefulness of the models as a tool in environmental landscape studies. Finally, we identify trends in computational modelling research to outline possible future directions of the discipline.

The standard experimental methods used for sampling suspended loads in large rivers are usually time consuming, unsafe, rather expensive, and have a limited spatial resolution. Acoustic Doppler current profilers (ADCPs), usually applied to measure the flow discharge, may also be used to assess the suspended sediment concentration by analyzing the backscattering acoustic strength. Though important efforts have been dedicated to test this method, results are not as reliable as engineering practices require, especially in large fluvial systems. In this paper, the correlation between the corrected backscatter from a 1,200kHz ADCP and the suspended concentration from a depthintegrated sampler is presented and discussed. Despite the assumptions required to utilize this method (i.e., monosized grain and homogeneous vertical concentration), the results showed acceptable differences when they were compared with traditional methods. An evaluation of the backscatter and attenuation of sound produced by fine and coarse material is presented. Finally, the total suspended load of bed sediment is assessed using moving-boat ADCP measurements and compared with results from the corresponding standard method. Differences are at most 46%. Fil: Latosinski, Francisco Guillermo. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Szupiany, Ricardo Nicolas. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Garcia Rodriguez, Carlos Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina. Universidad Nacional de Córdoba. Facultad de Cs.exactas Físicas y Naturales. Departamento de Hidraulica; Argentina Fil: Guerrero, Massimo. Universidad de Bologna; Italia Fil: Amsler, Mario Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentina

UNSW Water Research Laboratory Technical Report No. 2014/04

In view of present-day water stress, water transitions are necessary, incorporatingboth technological innovation and institutional reform. Water provisions andproblems involve a range of diverging interests and values, with which acorresponding range of actors and stakeholders are connected. This paperfocuses on both the social and the technological dynamics around riverdevelopment and management, and explores the margins and possibilities ofstakeholder involvement in water transitions. It draws on cases from TheNetherlands, Bangladesh and China. QC 20120109

11 páginas, 9 figuras, A synthetic review examines present knowledge of fluvial macroinvertebrates in Spain. Many works have been strictly descriptive, and most have aimed at the application of biotic indices in water quality studies. Nevertheless, new awareness in the 1980s, fostered by the Spanish Association of Limnology, has begun to stir works that carry more profound implications regarding community ecology and lotic ecosystems.