Bibliographies thématiques / River discharges

Littérature scientifique sur le sujet « River discharges »

Auteur : Grafiati
Publié le 25 mai 2024

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres

Choisissez une source :

Sommaire

Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « River discharges ».

À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.

Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.

Articles de revues sur le sujet "River discharges"

1

Klink, F. J. « An Alternative Approach to Achieve a Clean River Meuse ». Water Science and Technology 29, no 3 (1 février 1994) : 121–23. http://dx.doi.org/10.2166/wst.1994.0079.

Texte intégral
Résumé :
The municipality of Rotterdam and two regional drinking-water companies jointly started an action programme in an attempt to reduce the sources of pollution in consultation with the dischargers. Rotterdam aims to reach written agreements with each relevant discharger in which the discharger is committed to reduce his discharge in order to improve the Meuse water quality. In exchange Rotterdam relinquishes legal claims upon the discharger. Results of the measured discharges are presented. The 8 major dischargers of Br, Cd, NH4 and P each contribute up to 79% of the total contaminant discharge into the Meuse.
Styles APA, Harvard, Vancouver, ISO, etc.
2

Brilly, M., K. Kavčič, M. Šraj, S. Rusjan et A. Vidmar. « Climate change impact on flood hazard ». Proceedings of the International Association of Hydrological Sciences 364 (16 septembre 2014) : 164–70. http://dx.doi.org/10.5194/piahs-364-164-2014.

Texte intégral
Résumé :
Abstract. Climate changes have a high impact on river discharges and therefore on floods. There are a few different methods we can use to predict discharge changes in the future. In this paper we used the complex HBV model for the Vipava River and simple correlation between discharge and precipitation data for the Soča River. The discharge prediction is based on the E-OBS precipitation data for three future time periods (2011–2040, 2041–2070 and 2071–2100). Estimated discharges for those three future periods are presented for both rivers. But a special situation occurs at the confluence where the two rivers with rather different catchments unite, and this requires an additional probability analysis.
Styles APA, Harvard, Vancouver, ISO, etc.
3

Ponomarev, Evgenii I., Tatiana V. Ponomareva et Anatoly S. Prokushkin. « Intraseasonal Dynamics of River Discharge and Burned Forest Areas in Siberia ». Water 11, no 6 (31 mai 2019) : 1146. http://dx.doi.org/10.3390/w11061146.

Texte intégral
Résumé :
This study demonstrates the dependence between the forest burning rates and abnormal decrease in Siberian river discharges under the conditions of the permafrost zone. Our study area is in Central Siberia and Eastern Siberia/Yakutia. Four rivers (Podkamennaya Tunguska, Lower Tunguska, Aldan, and Viluy) were selected for the study. We analyzed the long-term and seasonal variation of river discharges (archive of The Global Runoff Data Centre for 1939–2015) together with the forest burning dynamics within the river basins (archive of Sukachev Institute of Forest for 1996–2015). We compared the discharges per year with the 77-year average value. Abnormally low levels of discharge constituted 58–78% of the averaged annual rate. An analysis of available chronologies of extreme fire events and relative burned areas (RBAs) showed a high correlation with intra-seasonal data on the runoff minima. The most significant response of river discharges to the wildfire effect was shown for the late summer/autumn season after extreme wildfires during the summer period. The deficit of the runoff was not explained by a low precipitation. Late summer and autumn anomalies of discharge were typical (r = −0.57…−0.77, p < 0.05) for rivers of Central Siberia in seasons of extreme forest burning. The correlation was lower for rivers of Eastern Siberia/Yakutia.
Styles APA, Harvard, Vancouver, ISO, etc.
4

Lou, Hezhen, Pengfei Wang, Shengtian Yang, Fanghua Hao, Xiaoyu Ren, Yue Wang, Liuhua Shi, Juan Wang et Tongliang Gong. « Combining and Comparing an Unmanned Aerial Vehicle and Multiple Remote Sensing Satellites to Calculate Long-Term River Discharge in an Ungauged Water Source Region on the Tibetan Plateau ». Remote Sensing 12, no 13 (6 juillet 2020) : 2155. http://dx.doi.org/10.3390/rs12132155.

Texte intégral
Résumé :
Research into global water resources is challenged by the lack of ground-based hydrometric stations and limited data sharing. It is difficult to collect good quality, long-term information about river discharges in ungauged regions. Herein, an approach was developed to determine the river discharges of 24 rivers in ungauged regions on the Tibetan Plateau on a long-term scale. This method involved coupling the Manning–Strickler formula, and data from an unmanned aerial vehicle (UAV) and the Gaofen-2, SPOT-5, and Sentinel-2 satellites. We also compared the discharges calculated by using the three satellites’ data. Fundamental information about the rivers was extracted from the UAV data. Comparison of the discharges calculated from the in-situ measurements and the UAV data gave an R2 value of 0.84, an average NSE of 0.79, and an RMSE of 0.11 m3/s. The river discharges calculated with the GF-2 remote sensing data and the in-situ experiments for the same months were compared and the R2, RMSE, and the NSE were 0.80, 1.8 m3/s, and 0.78, respectively. Comparing the discharges calculated over the long term from the measured in-situ data and the SPOT-5 and Sentinel-2 data gave R2 values of 0.93 and 0.92, and RMSE values of 2.56 m3/s and 3.16 m3/s, respectively. The results showed that the GF-2 and UAV were useful for calculating the discharges for low-flow rivers, while the SPOT-5 or the Sentinel-2 satellite gave good results for high-flow river discharges in the long-term. Our results demonstrate that the discharges in ungauged tributaries can be reliably estimated in the long-term with this method. This method extended the previous research, which described river discharge only in one period and provided more support to the monitoring and management of the tributaries in ungauged regions.
Styles APA, Harvard, Vancouver, ISO, etc.
5

Timuhins, Andrejs, Valērijs Rodinovs et Māris Kļaviņš. « Wavelet analysis of the Baltic region river runoff longh-term trends and fluctuations ». Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 64, no 5-6 (1 janvier 2010) : 229–35. http://dx.doi.org/10.2478/v10046-011-0009-1.

Texte intégral
Résumé :
Wavelet analysis of the Baltic region river runoff longh-term trends and fluctuations The study of changes in river discharge and flood regime can provide important information on climate change and its impacts. Wavelet analysis offers new possibilities to study changes of river discharge patterns in regard to periodical processes on a background of climate change. In this study wavelet analysis was used to study long-term changes of river discharge in the Baltic region. Periodic oscillations of discharge intensity, and low- and high-water flow years are common for the major rivers in the Eastern Baltic region. Main frequencies of river discharge were estimated to be 14, 28, 37 years for the studied rivers. Wavelet analysis allowed to identify similarities between the river discharge regime, and thus, the factors influencing it. Years of maximal and minimal discharges for major rivers were identified and the impact of large-scale atmospheric circulation processes on the river discharge was studied.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Shi, Xiaoqing, Tianling Qin, Hanjiang Nie, Baisha Weng et Shan He. « Changes in Major Global River Discharges Directed into the Ocean ». International Journal of Environmental Research and Public Health 16, no 8 (25 avril 2019) : 1469. http://dx.doi.org/10.3390/ijerph16081469.

Texte intégral
Résumé :
Under the influence of global climate change, the discharges of major global rivers directed into the ocean have undergone significant changes. To study the trends and causes in discharge variation, we selected 40 large rivers and analyzed their annual discharges near their estuaries from 1960 to 2010. The method of runoff variation attribution analysis based on the Budyko hypothesis for large-scale basins was developed, in which influencing factors of human activities and glacial melting factors were added to the formula. The contribution rate of climate factors and human activities to changes in discharge were quantitatively identified. Climatic factors include precipitation, evapotranspiration and glacial melting. Human activity factors include underlying surface and artificial water transfer. The contribution rate is determined by the elastic coefficient, which is obtained by the ratio of change rate of each factor and the change rate of runoff. The results indicated that the discharges predominantly showed downward trends with a few upward trends. Rivers in North America and Africa showed downward trends, and those in Europe principally showed upward trends. Climate was the main influencing factor of discharges changes, and only approximately 25% of river discharges were greatly affected by human activities. River discharges in 75% of the basins which mainly contains subtropical monsoon humid climate and savanna climate zones showed upward trends. In the four basins which are mainly contains tropical rainforest climate and tropical monsoon climate, they all showed downward trends. The trend of discharges in the temperate monsoon climate, temperate continental climate, and temperate maritime climate cannot be accurately judged because of irregular variation. The discharges in the mid-high latitudinal zones predominantly showed upward trends, while those in the mid-low latitudinal zones with the influence of human activities showed downward trends.
Styles APA, Harvard, Vancouver, ISO, etc.
7

He, Li. « Estimation of Flood Travel Time in River Network of the Middle Yellow River, China ». Water 12, no 6 (29 mai 2020) : 1550. http://dx.doi.org/10.3390/w12061550.

Texte intégral
Résumé :
The flood travel time (FTT) along the Longmen-Tongguan Reach, part of the stem channel of the Middle Yellow River, is shorter than 30 h, and estimating the FTT of different discharges propagating from Wubu Hydrology Station to Tongguan Hydrology Station is necessary. However, the propagation of floods in this river network, the main channel of the Wubu-Tongguan Reach and related tributaries, has rarely been analyzed due to the lack of geometry data. Thus, a one-dimensional (1D) dynamic model was selected to simulate the FTT along the WT reach. Firstly, the 1986 flood event was selected to calibrate the physical parameters in the hydraulic model. Secondly, the FTT with different discharges (500–9000 m3/s) were estimated with calibrated parameters. Thirdly, an empirical formula based on simulated results was fitted. This empirical formula could be used to describe the relation between discharges, distances to Tongguan Hydrology Station, and the FTT. Analyses showed that the discharges with minimum FTT were different for different tributaries. For the river reach between Wubu Hydrology Station and the Wuding River, the discharge and corresponding minimum FTT were 6000 m3/s and approximately 30.4–34 h, respectively. For the river reach between the Zhouchuan and Qingjian Rivers, the discharge and FTT were 3000–3500 m3/s and 21–26.8 h, respectively. The formula can be used to estimate the FTT of flood events, which would be cost-saving and time-saving for river management. Sensitivity analyses indicated that the FTT were sensitive to the Tongguan elevation and Manning’s roughness coefficient in the main channel.
Styles APA, Harvard, Vancouver, ISO, etc.
8

Chen, Y. C. « Flood discharge measurement of mountain rivers ». Hydrology and Earth System Sciences Discussions 9, no 11 (8 novembre 2012) : 12655–90. http://dx.doi.org/10.5194/hessd-9-12655-2012.

Texte intégral
Résumé :
Abstract. An efficient method that accounts for personal safety, accuracy and reliability for measuring flood discharge of mountain rivers is proposed. It is composed of new measurement method, tools, and techniques. Measuring flood discharge from mountain rivers by using conventional method is costly, time-consuming, and dangerous. Thus previous discharge measurements for mountainous areas were typically based on estimated precipitation, which alone cannot generate accurate measurements. This study applies a novel flood discharge measurement system composed of an Acoustic Doppler Profiler and crane system to accurately and quickly measure velocity distributions and water depths. Moreover a novel and efficient method for measuring discharge, which is based on the relationship between mean and maximum velocities and the relationship between cross-sectional area and gauge height is applied to estimate flood discharge. Flood discharge from mountain rivers can be estimated easily and rapidly by measuring maximum velocity in the river crosssection and the gauge height. The measured flood discharges can be utilized to create a reliable stage-discharge relationship for continuous estimations of discharge using records of water stage. The proposed method was applied to the Nanshih River, Taiwan. Results of measured discharges and estimated discharges only slightly differed from each other, demonstrating the efficiency and accuracy of the proposed method.
Styles APA, Harvard, Vancouver, ISO, etc.
9

Wrzesiński, Dariusz, et Leszek Sobkowiak. « Detection of changes in flow regime of rivers in Poland ». Journal of Hydrology and Hydromechanics 66, no 1 (1 mars 2018) : 55–64. http://dx.doi.org/10.1515/johh-2017-0045.

Texte intégral
Résumé :
Abstract The aim of this study is to detect changes in flow regime of rivers in Poland. On the basis of daily discharges recorded in 1951-2010 at 159 gauging stations located on 94 rivers regularities in the variability of the river flow characteristics in the multi-year period and in the annual cycle were identified and also their spatial uniformity was examined. In order to identify changes in the characteristics of river regime, similarities of empirical distribution functions of the 5-day sets (pentads) of discharges were analyzed and the percent shares of similar and dissimilar distributions of the 5-day discharge frequencies in the successive 20-year sub-periods were compared with the average values of discharges recorded in 1951-2010. Three alternative methods of river classification were employed and in the classification procedure use was made of the Ward’s hierarchical clustering method. This resulted in identification of groups of rivers different in terms of the degree of transformation of their hydrological regimes in the multi-year and annual patterns.
Styles APA, Harvard, Vancouver, ISO, etc.
10

Cai, Mingyong, Jixi Gao, Xuanmei Fan, Sihan Liu, Wenming Shen et Chaoyang He. « Estimation of River Discharge Using Unmanned Aerial Vehicle (UAV) Based on Manning Formula for an Ungauged Alpine River in the Eastern Qilian Mountains ». Water 14, no 13 (30 juin 2022) : 2100. http://dx.doi.org/10.3390/w14132100.

Texte intégral
Résumé :
River discharge is crucial to water resources development and ecological protection. However, in some arid areas of northwest China, it is still difficult to measure discharge accurately. In this study, unmanned aerial vehicle (UAV) imagery has been used to estimate river discharge at two river sections in the upper reaches of the Shiyang River in the eastern part of the Qilian Mountains based on the Manning formula. The estimated discharges at those two sections are 1.16 m3/s and 3.11 m3/s, respectively. Taking the discharges measured by an acoustic Doppler current profiler (ADCP) as the reference, the relative error of the estimates is below 5%, which is accurate enough for water resources management in mountain basin regions. Multiple high-resolution satellite images were also used to calculate water discharges at the two sections, which were in good agreement with the discharges estimated from UAVs. This study demonstrates the feasibility of using UAVs to estimate river discharge, which is of great significance for future regional-scale water resource assessments.
Styles APA, Harvard, Vancouver, ISO, etc.
Plus de sources

Thèses sur le sujet "River discharges"

1

Cloete, Gert Christiaan. « River discharges derived from single velocity measurements ». Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50087.

Texte intégral
Résumé :
Thesis (MScEng)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: This work investigates methods to theoretically determine the lateral velocity distribution across a river from which factors may be derived to translate a single point velocity into average velocity for the river as a whole. A wide range of field data from vanous nvers was analysed. This produced over a hundred velocity distributions with which to compare theoretical distribution results. Four theoretical approaches were considered: the one-dimensional method (Manning's equation), a two-dimensional flow formula solved as an initial-value-problem, a two dimensional flow formula solved as a boundary-value-problem and an empirical method developed from energy principles. The one-dimensional and initial-value-problem approaches were unsuccessful. The boundary-value and empirical approach did however produce promising results. Surprisingly the analysis of the field data revealed patterns of similarity which could produce accurate results without the need of a theoretical approach.
AFRIKAANSE OPSOMMING: Metodes word ondersoek om teoreties 'n laterale snelheidsverspreiding oor 'n rivier te bepaal en sodoende 'n faktor te vind waarmee 'n gemete enkelpuntsnelheid in die rivier omgeskakel kan word na 'n gemiddelde snelheid vir die rivier in geheel. Vloeimeetdata van verskeie nviere IS geanaliseer. Sodoende is meer as 100 snelheidsverspreidings gegenereer waarmee die teorie vergelyk kon word. Vier teoretiese benaderings is gevolg: Manning se een-dimensionele vloeivergelyking, 'n twee dimensionele vloei-vergelyking opgelos met behulp van 'n beginwaarde, 'n twee dimensionele vloei-vergelyking opgelos met behulp van randwaardes, en 'n empiriese metode ontwikkel vanuit energie beginsels. Die een-dimensionele- en beginwaarde-benaderings was me suksesvol me. Die randwaarde- en empiriese benaderings het wel belowende resultate gelewer. Selfs verwerking van die gemete stroommetings het waardevolle inligting gelewer: daar bestaan duidelike ooreenkomste in die snelheidsverspreidings wat gebruik kan word om die verspreidingsfaktor mee te bereken sonder om teoretiese oplossings te soek.
Styles APA, Harvard, Vancouver, ISO, etc.
2

Aulinas, Masó Montse. « Management of industrial wastewater discharges in river basins through agents'argumentation ». Doctoral thesis, Universitat de Girona, 2009. http://hdl.handle.net/10803/7804.

Texte intégral
Résumé :
La gestió de l'aigua residual és una tasca complexa. Hi ha moltes substàncies contaminants conegudes però encara moltes per conèixer, i el seu efecte individual o col·lgectiu és difícil de predir. La identificació i avaluació dels impactes ambientals resultants de la interacció entre els sistemes naturals i socials és un assumpte multicriteri. Els gestors ambientals necessiten eines de suport pels seus diagnòstics per tal de solucionar problemes ambientals.
Les contribucions d'aquest treball de recerca són dobles: primer, proposar l'ús d'un enfoc basat en la modelització amb agents per tal de conceptualitzar i integrar tots els elements que estan directament o indirectament involucrats en la gestió de l'aigua residual. Segon, proposar un marc basat en l'argumentació amb l'objectiu de permetre als agents raonar efectivament. La tesi conté alguns exemples reals per tal de mostrar com un marc basat amb agents que argumenten pot suportar diferents interessos i diferents perspectives. Conseqüentment, pot ajudar a construir un diàleg més informat i efectiu i per tant descriure millor les interaccions entre els agents. En aquest document es descriu primer el context estudiat, escalant el problema global de la gestió de la conca fluvial a la gestiódel sistema urbà d'aigües residuals, concretament l'escenari dels abocaments industrials. A continuació, s'analitza el sistema mitjançant la descripció d'agents que interaccionen. Finalment, es descriuen alguns prototips capaços de raonar i deliberar, basats en la lògica no monòtona i en un llenguatge declaratiu (answer set programming).
És important remarcar que aquesta tesi enllaça dues disciplines: l'enginyeria ambiental (concretament l'àrea de la gestió de les aigües residuals) i les ciències de la computació (concretament l'àrea de la intel·ligència artificial), contribuint així a la multidisciplinarietat requerida per fer front al problema estudiat. L'enginyeria ambiental ens proporciona el coneixement del domini mentre que les ciències de la computació ens permeten estructurar i especificar aquest coneixement.
Wastewater management is a very complex task. There is a high number of known and an increasing number of unknown pollutants whose individual and collective effects are very difficult to predict. Identifying and evaluating the impacts of environmental problems resulting from the interactions between our social system and its natural environment is a multifaceted critical issue. Environmental managers require tools to support their diagnoses for solving these problems. The contributions of this research work are twofold: first, to propose the use of an agent-based modelling approach in order to conceptualize and integrate all elements that are directly or indirectly involved in wastewater management. Second, to propose a framework based on argumentation that allows to reason effectively. The thesis provide some real examples to show that an agent-based argumentation framework can deal with multiple interests and different agents' perspectives and goals. This help to build a more effective and informed dialog in order to better describe the interaction between agents. In this document we first describe the context under study, scaling down the global river basins system to the urban wastewater systems and giving some more details for the specific scenario of industrial wastewater discharges. Then, we analyze the system in describing intelligent agents that interact. Finally, we propose some reasoning and deliberation prototypes by using an argumentation framework founded on non-monotonic logics (i.e. permitting to learn things that were previously not known) and the answer set programming specification language (i.e. a declarative programming language). It is important to remark that this thesis links two disciplines: environmental engineering (specifically the area of wastewater management) and computer science (specifically the area of artificial intelligence), contributing to the required multidsciplinarity needed to confront the complexity of the problem under study. From environmental engineering we obtain the domain knowledge whereas the computer science field permits us to structure and specify this knowledge.
Styles APA, Harvard, Vancouver, ISO, etc.
3

Holt, Tom. « The effect of proposed Soviet river diversions on Arctic Sea ice processes ». Thesis, University of East Anglia, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278089.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Jian, Jun. « Predictability of Current and Future Multi-River discharges : Ganges, Brahmaputra, Yangtze, Blue Nile, and Murray-Darling Rivers ». Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19777.

Texte intégral
Résumé :
Thesis (Ph.D)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2008.
Committee Chair: Judith Curry; Committee Chair: Peter J Webster; Committee Member: Marc Stieglitz; Committee Member: Robert Black; Committee Member: Rong Fu.
Styles APA, Harvard, Vancouver, ISO, etc.
5

Dias, Francisco Josà da Silva. « HidrodinÃmica of discharges to the river estuary of the Rio Jaguaribe (CE.) ». Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1728.

Texte intégral
Résumé :
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
The increasing of greenhouse gases and of the human population, results in growing awareness of water resources managers of freshwater availability in the world, mostly in the tropics. Knowing that Brazil still presents an excellent availability of freshwater, with 33.000 m3.inhabitant.years, the Ministry of the Environment, in a recent publication, stands out that the Basins of the Eastern Northeast Atlantic, in which the Jaguaribe river is inserted, already presents a high level of estress of their water bodies, with only 45% of the minimum value of the 2.500 m3.inhabitant.years suggested by the Organization of United Nations (ONU) as being the minimum required to the exercise of the human social and economic activities. The water discharge of the Jaguaribe river basin, with 72,043 km2 of area and 633 km2 of extension, measured at the nearest seaward station, indicates historical average outflows varying between 14 Â 23 m3.s-1 in the dry season and up to 235 Â 434 m3.s-1 in the rain season. However, this fluvial discharge can not be considered as discharging to the ocean, because the basins reservoirs holds back 87% of the fluvial flow. The modeling of river flow performed in the present study at tidal river zone (ZR) and the mixture zone (ZM) interface under quadrature tides in February and June 2006, and under spring tide, in September 2005, showed total outflow varying between 58 and 183 m3.s-1 in the evaluated period. The residence time (TR) of estuarine waters was dependent on the inter-annual climatic variability varying from 3 to 2 hours in the dry station, in 2005 and 2006, respectively, and 12 hours at the season, evidencing that the volume of freshwater is not a limiting main factor for the ability of the water mass to breach the operating sea strength in the region, but the total outflow is significant, mainly during the dry station when the estuary is leached by sea waters that increase its renew capacity. Highest salinities was observed in the periods when the estuary presented lower input of fluvial waters, reaching the 36,1. The particulate suspended matter (MPS) varied seasonality between 7 and 89,7 mg/L. The MPS in September of 2005 and June of 2006 was strongly organic, and the MPS observed in February of 2006 was mostly of carbonate origin. The discharges of MPS and metals associated with it to the estuary, presented the highest values in the period of larger fluvial flow, varying between 1,9 104 x ton.year-1 in September of 2005 (12% of freshwater origin) to 2,5 105 x ton.year-1 in the period with 95% of freshwater. The same behavior is observed for the discharges of metals, such as; Fe, which in September of 2005 presented a discharge of 3 x 102 ton.year-1, whereas in the period of larger fluvial flux of 1,2 x 104 ton.year-1, having as an exception the Pb flux, which presented the highest values in the period of marine domain.
O crescente aumento da emissÃo dos gases do efeito estufa (GEE) e da populaÃÃo humana fez com que os gestores dos recursos hÃdricos redobrassem sua atenÃÃo sobre a razÃo demanda/disponibilidade hÃdrica no mundo e, principalmente nos trÃpicos. Mesmo sabendo que o Brasil ainda apresenta um excelente potencial hÃdrico, com 33.000 m3.hab-1.ano-1, o MinistÃrio do Meio Ambiente, em recente publicaÃÃo, ressalta que a bacia do AtlÃntico Nordeste Oriental, no qual o rio Jaguaribe esta inserido, jà apresenta um elevado nÃvel de estresse hÃdrico por apresentar apenas 45% do valor mÃnimo de 2.500 m3/hab/ano apontado pela ONU como sendo suficientes para a manutenÃÃo das atividades humanas, sociais e econÃmicas. A descarga hÃdrica da bacia de drenagem do rio Jaguaribe, (72.043 km2 de Ãrea e 633 km2 de extensÃo) medida pela estaÃÃo fluviomÃtrica mais prÃxima a sua foz, na regiÃo do mÃdio Jaguaribe, indica vazÃes mÃdias histÃricas variando entre 14 +23 m3.s-1 na estaÃÃo de seca atà 235 +434 m3.s-1 na estaÃÃo de chuvas. No entanto, esta descarga fluvial nÃo deve ser considerada como o aporte fluvial da bacia para o oceano, pois a aÃudagem retem 87% do fluxo fluvial do Jaguaribe em mais de 4000 barramentos. A modelagem hidrodinÃmica utilizada neste estudo a partir de medidas realizadas na interface ZR/ZM em marÃs de quadratura, fevereiro e junho de 2006, e do tipo sizÃgia, setembro de 2005, totalizou vazÃes hÃdricas entre 58 a 183 m3.s-1, no perÃodo avaliado. O tempo de residÃncia (TR) das Ãguas estuarinas mostrou dependÃncia da variabilidade climÃtica anual e inter-anual variando de 3 a 2 horas na estaÃÃo seca, em 2005 e 2006, respectivamente, enquanto que em Ãpoca de chuvas foi igual a 12 horas. Este resultado sugere que o volume de Ãgua doce nÃo à o fator limitante da competÃncia da massa de Ãgua para romper as forÃantes marinhas atuantes na regiÃo, mas a vazÃo hÃdrica total à significativa, principalmente durante a estaÃÃo seca quando o estuÃrio à lixiviado por Ãguas marinhas que aumentam sua capacidade de depuraÃÃo. As maiores salinidades foram observadas nos perÃodos em que o sistema estuarino apresentou menor aporte hÃdrico fluvial, chegando a 36,1 quando o percentual de Ãgua doce foi menor que 15%. O material particulado em suspensÃo (MPS) variou sazonalmente entre 7 e 89,7 mg/L. O MPS em setembro de 2005 e junho de 2006 foi fortemente orgÃnico, enquanto que o MPS coletado em fevereiro de 2006 foi de origem carbonÃtica. As descargas de MPS e de metais no MPS oriundos da bacia de drenagem para o estuÃrio, apresentaram variabilidade sazonal crescente de acordo com o aumento das chuvas e com os maiores valores no perÃodo de maior aporte fluvial. O mesmo padrÃo de comportamento do MPS à observado para as descargas dos metais, tais como; Fe, Al, Mn, Cu e Zn, tendo como exceÃÃo o comportamento do Pb no MPS, que apresentou os maiores valores no perÃodo de domÃnio marinho.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Millier, Helen Katherine Genevieve Ruth. « Evaluation of the impact of treated wastewaters discharges on river water phosphorus and metal concentrations ». Thesis, Kingston University, 2009. http://eprints.kingston.ac.uk/20406/.

Texte intégral
Résumé :
It is standard practice for sewage treatment plants to discharge treated wastewaters to water-bodies and, in the UK, this has been the custom since the first sewerage system was completed in London around 1865. Before sewerage networks untreated sewage waste was discharged to rivers (wet carriage) or removed from domestic dwellings by "honey wagons" (dry carriage) and taken to rural areas to be used as fertiliser (Adams & Papa, 2000). Wastewater inputs to rivers are governed by discharge consents issued by the Environment Agency in accordance with existing legislation, taking into account the physical and ecological characteristics of the receiving river. However, it has become apparent in recent years that wastewaters may have a detrimental effect on receiving rivers, particularly in terms of nutrients as they frequently discharge phosphorus (P) in concentrations > 1.0 mg P 1[sup]-1. Metals are not specifically removed by the wastewater treatment process and, although their affinity for particulates results in some removal during processing, it is suspected that dissolved metals may be present in treated wastewaters. In 2000, the E.C. introduced the Water Framework Directive, which requires water bodies within member countries to attain "good ecological status" by 2015 in terms of biological and physico-chemical water quality. An umbrella Directive, it combines existing legislation on a range of contaminants including nutrients and metals with additional environmental standards to improve the quality of European waters. The purpose of this study was to consider whether the discharge of treated sewage wastewaters is likely to prevent rivers from achieving the standards required by this legislation. During an eighteen month period, water samples were collected from two second order rivers, the Bourne and Hogsmill, up and downstream of sewage treatment works. Samples were analysed for a range of P species and metals in filtered and unfiltered river water. Ultra-filtration was carried out on a selection of samples, as finer fractions are likely to be more bioavailable. River flow data was used to calculate potential contaminant loads downstream of the input source; this data was compared against published concentrations of agricultural derived P, historically considered the major contributor of P to UK riverine waters. Until the introduction of P removal processing at the Hogsmill, downstream concentrations of all P species in both rivers, were greater than upstream by an order of magnitude. P removal reduced P concentrations in the Hogsmill by more than 60% although they remain significantly greater than upstream. The majority of P occurred as soluble reactive P (SRP), the most bioavailable species, and the continuous nature of wastewaters discharge meant concentrations were high during the growth season. Current P-removal processes may not remove sufficient P to meet quality targets recommended by the U.K. Technical Advisory Group on the Water Framework Directive. Estimated P loads upstream of the wastewaters outflow are < 8 kg SRP day[sup]-1 for both rivers, the combination of increased P concentrations and greater river water volume downstream of the outflow result in estimated P loads of > 45 kg SRP day[sup]-1 in the Bourne and > 80 kg SRP day[sup]-l for the Hogsmill (after P-stripping). Comparison of P export figures from treated sewage wastewaters, calculated using daily load figures, with those from agriculture indicate that in all but the most rural catchments, sewage wastewaters are a greater source of P. Downstream, dissolved metals concentrations were not significantly different from upstream except for As in the Bourne and Pb in the Hogsmill; neither metal exceeded regulatory limits. River sediment from the Hogsmill and Bourne, and two additional rivers receiving sewage wastewaters, the Mole and Blackwater, were analysed for total metals and P. The ability of sediments to release (SRP) was investigated using kinetic release analysis. In the absence of U.K. standards, metals concentrations in sediments were assessed using the US EPA sediment quality guidelines (SQG). A range of metals in sediments from both the Hogsmill and Mole exceeded SQG to the extent that biota was likely to be affected. Although the greatest concentrations of total phosphorus in sediment were found in the Bourne, it is the Hogsmill which exhibits most potential for the release of SRP from sediment to the water column.
Styles APA, Harvard, Vancouver, ISO, etc.
7

Drake, Chad Walter. « Assessment of flood mitigation strategies for reducing peak discharges in the Upper Cedar River watershed ». Thesis, University of Iowa, 2014. https://ir.uiowa.edu/etd/4617.

Texte intégral
Résumé :
This thesis evaluates the effectiveness of several flood mitigation strategies for reducing peak discharges in the Upper Cedar River Watershed located in northeast Iowa. Triggered by record flooding in June 2008, the Iowa Watersheds Project was formed to evaluate and construct projects for flood reduction. The Upper Cedar was selected as a pilot watershed and a hydrologic assessment was performed to better understand its flood hydrology. Evaluation of different flood mitigation strategies was performed with HEC-HMS, a lumped parameter surface water model. The hydrologic model development is described and the model applications are analyzed. The HMS model was used in several ways to better understand the flood hydrology of the Upper Cedar River Watershed. First, the runoff potential of the basin was assessed to identify the primary runoff generation mechanisms. Areas with agricultural land use and moderately to poorly draining soils had the highest runoff potential. Following, the model was used to evaluate the impact of several flood mitigation strategies - increased infiltration through land use changes, increased infiltration through soil improvements, and added storage in the watershed to hold runoff temporarily and reduce downstream flood peaks - for different flood frequency events (the 10-, 25-, 50-, and 100-year, 24-hour design rain storms) and the June 2008 flood. Although each scenario is hypothetical and simplified, they do provide benchmarks for the types of reductions physically possible and the effectiveness of strategies relative to one another. In order to reduce the impacts of flooding in the Upper Cedar, a combination of projects that enhance infiltration and/or store excess runoff will be necessary.
Styles APA, Harvard, Vancouver, ISO, etc.
8

Ayalew, Tibebu Bekele. « Physical basis of the power-law spatial scaling structure of peak discharges ». Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1537.

Texte intégral
Résumé :
Key theoretical and empirical results from the past two decades have established that peak discharges exhibit power-law, or scaling, relation with drainage area across multiple scales of time and space. This relationship takes the form Q(A)= $#945;AΘ where Q is peak discharge, A is the drainage area, Θ is the flood scaling exponent, and α is the intercept. Motivated by seminal empirical studies that show that the flood scaling parameters α and Θ change from one rainfall-runoff event to another, this dissertation explores how certain rainfall and catchment physical properties control the flood scaling exponent and intercept at the rainfall-runoff event scale using a combination of extensive numerical simulation experiments and analysis of observational data from the Iowa River basin, Iowa. Results show that Θ generally decreases with increasing values of rainfall intensity, runoff coefficient, and hillslope overland flow velocity, whereas its value generally increases with increasing rainfall duration. Moreover, while the flood scaling intercept is primarily controlled by the excess rainfall intensity, it increases with increasing runoff coefficient and hillslope overland flow velocity. Results also show that the temporal intermittency structure of rainfall has a significant effect on the scaling structure of peak discharges. These results highlight the fact that the flood scaling parameters are able to be estimated from the aforementioned catchment rainfall and physical variables, which can be measured either directly or indirectly using in situ or remote sensing techniques. The dissertation also proposes and demonstrates a new flood forecasting framework that is based on the scaling theory of floods. The results of the study mark a step forward to provide a physically meaningful framework for regionalization of flood frequencies and hence to solve the long standing hydrologic problem of flood prediction in ungauged basins.
Styles APA, Harvard, Vancouver, ISO, etc.
9

Fowler, Vivienne Frances. « The impacts of chemical discharges on the reproductive biology of the bullhead Cottus gobio and the dipper Cinclus cinclus in the Tamar catchment ». Thesis, University of Exeter, 2011. http://hdl.handle.net/10036/3092.

Texte intégral
Résumé :
It is now well established that a wide range of natural and anthropogenic chemicals present in the aquatic environment have the potential to disrupt the endocrine system of many organisms. In fish, many of these effects appear to be of a feminising nature, including stimulation of vitellogenin production and induction of intersex. In piscivorous birds these so called endocrine disrupting contaminants have been shown to impair reproduction, influencing reproductive behaviour, sex ratio, eggshell thickness and reproductive success. The effects seen in fish have been associated with high levels of oestrogenic activity in the effluent from waste water treatments works (WwTWs), but few studies have focused on the effects of WwTWs effluents on birds. In this thesis, the effects of effluents from WwTWs on fish and birds were investigated in the Tamar catchment, SW England. The work spanned making detailed assessment on the oestrogenic and anti-androgenic activity of 3 WwTWs effluents, using a variety of water sampling techniques and applying both recombinant yeast oestrogen screen (YES) and recombinant yeast androgen screen (anti-YAS) bioassays to quantify the different hormonal activities. A survey was undertaken of the hormonal activities at 13 sites to determine concentrations of contaminants in the surface waters throughout the Tamar catchment, using both recombinant yeast screens and targeted analytical chemistry for specific pollutants (LC/MS-TOF and GCMS). An ELISA was developed to quantify vitellogenin (VTG) in the bullhead (our study fish sentinel) as a biomarker of oestrogen exposure, and evidence of endocrine disruption was investigated in wild populations of the bullhead, Cottus gobio and the dipper, Cinclus cinclus. Macroinvertebrates from upstream and downstream of three WwTW's effluent discharges and from three sampling sites were also sampled as an index of overall water quality in the Tamar catchment, and as an assessment of food availability for the bullheads and dippers. For the studies on the hormonal activities in three WwTWs in the Tamar catchment, samples were collected by both spot and passive sampling; passive samplers (in replicate) were placed in the effluent discharges for a three week period, and collected on days 7, 14 and 21, spot samples were taken simultaneously. Measurement of total oestrogenic and total anti-androgenic activity was conducted using the YES and anti-YAS, respectively. Spot and passive samples were collected from 13 sites within the Tamar catchment (sampling sites were >2 km downstream of effluent discharges). Additionally, liquid chromatography mass spectrometry time-of-flight (LC/MS-TOF) was used to measure the concentration of oestrone (E1), 17β-oestrodiol (E2) and 17α-ethinylestradiol (EE2) in each sample. Gas chromatography mass spectrometry (GCMS) was used to measure the concentration of individual PBDE and PCB congeners in the spot samples only. Levels of oestrogenic and anti-androgenic activity observed in the WwTWs effluent were comparable with those measured in effluents in the UK and in other countries. Surface waters of the Tamar, away from the WwTWs effluent discharges, contained very little oestrogenic activity (<1.1 ng E2 EQs L-1), and anti-androgenic activity was undetectable. Quantification of oestrogenic activity using passive samplers showed an increasing amount of total oestrogenic activity between days 7 and 21 when measured by the both the YES and LC/MS-TOF. Low levels of PBDE congeners 47, 99, 100, 138 and 153 were detected in the spot samples taken from the Tamar catchment, with BDE 47 being the most abundant. In contrast PCBs were undetectable. Neither PBDEs nor PCBs were detected in any of the extracts from the passive samples. No assay was available to measure VTG (one of the most widely used biomarkers of oestrogen exposure in fish) in the bullhead and so an enzyme linked immunosorbant assay (ELISA) was developed for application to studies on wild bullheads in the Tamar catchment. The bullhead vitellogenin (bh-VTG) ELISA was developed successfully, and proved to be sensitive and robust, with a detection range between 10.5 and 300 ng bh-VTG mL-1 (undiluted), comparing favourably with other fish VTG ELISAs. Plasma VTG concentrations measured in male bullheads (collected from the same sites as for the water samples) ranged from below the limit of detection to 990 ng bh-VTG mL-1. Whether these upper levels in the range reflected VTG induction was difficult to conclude. Because of this controlled caged exposures with bullheads and trout were used to assess the relative levels of oestrogenicity in two key WwTWs effluent discharges and to determine the response sensitivity of the bullheads (and trout) to those effluents. These controlled exposures found no responses in plasma VTG in bullheads (ranging between 126 and 934 ng bh-VTG mL-1) suggesting a lack of sensitivity for VTG induction. This was supported by the inability to induce VTG in fish held in the laboratory and treated with steroidal oestrogens. For the effluent exposures on the caged rainbow trout, it was also found that there was no significant induction of VTG, a species normally sensitive to oestrogens. These findings may indicate that the fish were highly stressed due to the river being in spate and the movement of the cages during the controlled exposures. It may also be the case, however, that the use of immature female rainbow trout with a highly variable baseline plasma VTG concentration may prevent any detection of a response. There were no signs of sexual disruption in any of the gonads analysed from either male or female wild bullheads, demonstrating that any hormonal activity present in the catchment away from the WwTWs effluents was not sufficient to induce adverse effects on reproductive development. An interesting feature noted in the male testes of the bullheads was the presence of spermatid masses, which have been recorded in 10 other Cottidae species, but not previously in the bullhead. For the studies on dippers, eggs were collected from the nests of breeding dippers to measure for sperm numbers and morphology from sperm trapped in the perivitelline membrane (PVM), and the yolks were analysed for PBDEs, PCBs and organochlorine pesticides (OCPs) by GCMS, for E1, E2, and EE2 by LC/MS-TOF. Eggs of the dipper were collected from nests at the 13 sampling sites, plus an additional three sites and over three years of field study. The number of sperm trapped in the PVM ranged between three and 188, with a mean of 68.78 ± 8.78 SE. Dipper sperm had not previously been characterised, and was found to be similar to other passerine sperm, in that the head was helical, complemented by a mitochondrial helix or keel, which continued in a spiral around the flagellum. Sperm were classed as ‘abnormal’ if they did not adhere to this typical structure. No assessment of motility could be made in relation to the structural abnormalities seen. Contaminants in the dipper eggs were dominated by BDE 99, an unusual result considering the dippers aquatic lifestyle. PCB 153 was the most common PCB, and p,p’-DDE was the most abundant OCP; all other pesticides tested were below the limit of detection, as were the levels of all three steroid oestrogens. There was inter- and intra-nest variability between contaminant burdens in all eggs as well as the number of sperm trapped in the PVM, but there was no relationship between sperm number and the level of contaminant loadings in the eggs. There were no correlations between contaminants and oestrogenic activity measured in the water samples, and plasma VTG concentrations in bullheads or contaminant loadings in eggs, or indeed sperm number. Analysis of macroinvertebrate assemblages proved that the surface waters of the Tamar catchment were of ‘very good’ quality, even in close proximity to WwTWs effluent discharges.
Styles APA, Harvard, Vancouver, ISO, etc.
10

Klingner, William. « The effects of increased infiltration and distributed storage on reducing peak discharges in an agricultural Iowa watershed : the Middle Raccoon River ». Thesis, University of Iowa, 2014. https://ir.uiowa.edu/etd/4664.

Texte intégral
Résumé :
The devastating Floods throughout Iowa in 2008 caused homes to be lost, people to be displaced, and cost billions in economic damages. This left State Officials pondering how to limit the damages of large magnitude floods in the future. From the legislative sessions following this tragedy came the Iowa Flood Center and funding through the Department of Housing and Urban Development (among others) to begin the Iowa Watersheds Project. The project was tasked with the planning, implementation and evaluation of watershed projects to lessen the severity and frequency of flooding in Iowa. One test watershed studied was the Middle Raccoon River watershed in West Central Iowa. To study the impacts of basin-wide flood mitigation strategies on the Middle Raccoon River watershed, the hydrologic modeling software HEC-HMS was used in conjunction with the geographic analysis software, ArcGIS. A model was developed and calibrated to best represent the observed hydrologic response at USGS stream gages located at Bayard, IA and Panora, IA. Once complete, a series of flood mitigation techniques were applied to the watershed model, and run with the 10-, 25-, 50-, and 100-year SCS design storms. These techniques include increasing infiltration by modifying land use, and applying a distributed storage system (ponds). Both practices are shown to have the ability to reduce peak discharge, from 4 percent to 56 percent, depending on the location in the watershed, the severity of the design storm, and the extent of the flood mitigation technique. Although research describing the effects of distributed storage and increased infiltration currently exist, this study details the process in which these effects can be modeled in a heavily agricultural Iowa watershed using a simplified lumped parameter model (HEC-HMS). With recent major flooding events in Iowa, the methods and tools in this report will be valuable in predicting the effectiveness of flood projects prior to project construction.
Styles APA, Harvard, Vancouver, ISO, etc.
Plus de sources

Livres sur le sujet "River discharges"

1

Lawlor, Sean M. Determination of channel-morphology characteristics, bankfull discharge, and various design-peak discharges in western Montana. Reston, Va : U.S. Geological Survey, 2004.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Lawlor, Sean M. Determination of channel-morphology characteristics, bankfull discharge, and various design-peak discharges in western Montana. Reston, Va : U.S. Geological Survey, 2004.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Lawlor, Sean M. Determination of channel-morphology characteristics, bankfull discharge, and various design-peak discharges in western Montana. Reston, Va : U.S. Geological Survey, 2004.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Lawlor, Sean M. Determination of channel-morphology characteristics, bankfull discharge, and various design-peak discharges in western Montana. Reston, Va : U.S. Geological Survey, 2004.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Lawlor, Sean M. Determination of channel-morphology characteristics, bankfull discharge, and various design-peak discharges in western Montana. Reston, Va : U.S. Geological Survey, 2004.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

Lawlor, Sean M. Determination of channel-morphology characteristics, bankfull discharge, and various design-peak discharges in western Montana. Reston, Va : U.S. Geological Survey, 2004.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

Lawlor, Sean M. Determination of channel-morphology characteristics, bankfull discharge, and various design-peak discharges in western Montana. Reston, Va : U.S. Geological Survey, 2004.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Parrett, Charles. Flood discharges in the upper Mississippi River basin, 1993. [Washington, D.C.] : U.S. G.P.O., 1993.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Parrett, Charles. Flood discharges in the upper Mississippi River basin, 1993. [Washington, DC] : U.S. G.P.O., 1993.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Wharton, Geraldene. Guidelines for estimating flood discharges in Britain from river channel dimensions. Southampton : University of Southampton, Dept. of Geography, 1989.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
Plus de sources

Chapitres de livres sur le sujet "River discharges"

1

Devlin, Michelle, et Jon Brodie. « Nutrients and Eutrophication ». Dans Springer Textbooks in Earth Sciences, Geography and Environment, 75–100. Cham : Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-10127-4_4.

Texte intégral
Résumé :
AbstractExcess nutrientsfrom fertiliser application, pollution discharge and water regulations outflow through rivers from lands to oceans, seriously impact coastal ecosystems. Terrestrial runoff of waters polluted with nutrients (primarily nitrogen [N] and phosphorus [P] compounds) from point source/s, such as sewage treatment plant (STP) discharges, and diffuse sourcesvia river discharges, such as fertiliser losses, are having devastating adverse effects in coastal and marine ecosystems globally (Carpenter et al., Ecol Appl 8:559–568, 1998; Halpern et al., Science 319:948–952, 2008; Crain et al., Ecol Lett 11:1304–1315, 2008; Smith and Schindler, Trends Ecol Evol 24:201–207, 2009). The nutrients can be dissolved such as dissolved nitrate and Phosphate typically discharged from STPs or agricultural runoff or in a particulate form, often associated with soil erosion.
Styles APA, Harvard, Vancouver, ISO, etc.
2

Santos, Rodrigo, et João Nuno Fernandes. « Estimation of River Flow Discharges Using Image Processing ». Dans Testing and Experimentation in Civil Engineering, 363–74. Cham : Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-29191-3_30.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Sfîcă, Lucian, Andreea-Diana Damian, Adrian Grozavu, Andrei-Ion Niță et Marius-Victor Bîrsan. « Synoptic Conditions Associated with Floods and Highest Discharges on Lower Danube River (1980–2010) ». Dans The Lower Danube River, 329–55. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-03865-5_11.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Quraishee, G. S. « Variation in the Indus River Discharges and their Hazards ». Dans Natural and Man-Made Hazards, 369–75. Dordrecht : Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1433-9_26.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Babovic, V., et M. Keijzer. « Forecasting of River Discharges in the Presence of Chaos and Noise ». Dans Flood Issues in Contemporary Water Management, 405–19. Dordrecht : Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4140-6_42.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

Gnjato, Slobodan, Tatjana Popov, Goran Trbić et Marko Ivanišević. « Climate Change Impact on River Discharges in Bosnia and Herzegovina : A Case Study of the Lower Vrbas River Basin ». Dans Climate Change Management, 79–92. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-03383-5_6.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

de Jonge, V. N. « Response of the Dutch Wadden Sea ecosystem to phosphorus discharges from the River Rhine ». Dans North Sea—Estuaries Interactions, 49–62. Dordrecht : Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-2000-2_5.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Kohnová, S., et J. Szolgay. « Regional Estimation of Design Flood Discharges for River Restoration in Mountainous Basis of Northern Slovakia ». Dans Flood Issues in Contemporary Water Management, 41–47. Dordrecht : Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-011-4140-6_4.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Hiyama, Tetsuya, Shigemi Hatta et Hotaek Park. « River Discharge ». Dans Ecological Studies, 207–29. Singapore : Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-6317-7_9.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Polonsky, A., E. Voskresenskaya et V. Belokopytov. « Variability of Northwestern Black Sea Hydrography and River Discharges As Part of Global Ocean-Atmosphere Fluctuations ». Dans Sensitivity to Change : Black Sea, Baltic Sea and North Sea, 11–24. Dordrecht : Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5758-2_2.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.

Actes de conférences sur le sujet "River discharges"

1

Bojilova, Elena. « STATISTICAL ANALYSIS OF YANTRA RIVER FLOW ». Dans 23rd SGEM International Multidisciplinary Scientific GeoConference 2023. STEF92 Technology, 2023. http://dx.doi.org/10.5593/sgem2023/3.1/s12.20.

Texte intégral
Résumé :
The study is focused on statistical analysis of river discharges. The registered river flow regime and hydrological characteristics of Yantra River are investigated. Yantra watershed is situated in North Bulgaria and belongs to Danube river basin Directorate. The current study is focused on the low flows. Thirteen hydrometrics stations located in the watershed are available for the investigation. Data used are from monitoring network of the National institute of meteorology and hydrology, Bulgaria. The flow duration analysis was carried out for each gauged river within watershed. Flow duration analysis provides information on the percentage of time that flows are equalled or exceeded. Some baseflow indices were calculated in order to estimate the relative contribution of groundwater or baseflow. The obtained results clearly show a significant contribution of subsurface inflow to surface river runoff. The time of occurrence of minimum daily discharges (by month) were extracted from database and values were analysed. The minimum daily water discharge has the greatest frequency in the four summer months based on the performed analysis. In second place are the winter months when we work with three seasons each with four months duration. The magnitude of the low flow event was studied using frequency analysis. The probability of occurrence of different flows was calculated. Regional regression analysis was applied. Regionalization scheme and regression curves are presented and discussed. The obtained results show that the most of the rivers from the watershed have a similar behaviour at low flow. This study is focused on flow metrics that best describe the flow regime and the hydrological characteristics of Yantra river. Furthermore, hydrological studies are important for all types of environmental investigations � fish habitat, water intakes, stream productivity, etc. In the recent years we are dealing with co-called ecological flow. Particularly the low flow statistical analysis is crucial for determination of ecological flows in the sense of European water framework directive.
Styles APA, Harvard, Vancouver, ISO, etc.
2

Kolesnik, Andrii, et Zhannetta Shakirzanova. « Methodological basics of forecasting floods on the rivers of Transcarpattia ». Dans International Conference of Young Scientists on Meteorology, Hydrology and Environmental Monitoring. Ukrainian Hydrometeorological Institute, 2023. http://dx.doi.org/10.15407/icys-mhem.2023.011.

Texte intégral
Résumé :
The formation of floods of mixed origin in the cold and warm periods of the year is characteristic of the rivers of Transcarpathia. They are often accompanied by significant and prolonged flooding of territories, sometimes with catastrophic consequences. For the purpose of warning about dangerous hydrological phenomena, an urgent task is hydrological forecasting of maximum levels and water flows during periods of floods on rivers. The object of the research is the Tysa River and its tributaries, which are characterized by the formation of maximum runoff from melting snow and rainfall in the winter-spring period. The Carpathians, which occupy the southwestern part of Ukraine, play a major role in shaping the climate of the territory under consideration, where a mountain climate associated with heavy precipitation is created. It should be noted that heavy precipitation in the Tysa river basin is characterized by a long duration and intensity of precipitation. Such rains are accompanied by the rapid formation of catastrophic river floods, mudslides and floods. The purpose of this work is the analysis of modern mathematical models for forecasting the maximum water levels and discharges of floods and the creation of a methodology for short-term forecasting of the flood flow of Transcarpathian rivers. Mathematical models of rain and snow-rain runoff of mountain rivers were developed as structural components of basin prognostic systems (in the Tysa basin - "Tysa", in the Latorica river basin - "LATORICA", 2011). Such models were created at the Ukrainian Research Hydrometeorological Institute of the State Emergency Service of Ukraine and the National Academy of Sciences of Ukraine (UkrHMI) https://uhmi.org.ua/dep/hydro/ and are implemented in the operational activities of the Transcarpathian Regional Center for Hydrometeorology http://gmc.uzhgorod.ua/vgpro.php. These models are conceptual with concentrated parameters and serve for short-term forecasting of runoff (discharges /levels) during rain and snow-rain floods and long-term forecasting of spring flood characteristics. In foreign practice, a new generation MIKE 11 modeling complex has been developed and is used in the operational practice of European countries. In UkrHMI, the adaptation of the NAM RR MIKE 11 hydrological model to calculation and forecast modeling of both average daily and maximum discharges of the mountain rivers of Transcarpathia (the rivers Tysa, Rika, Borzhava). The quality of NAM module calibration is related to the quality and availability of hydrometeorological data and the impact of anthropogenic activities on river flow. In addition, as part of the adaptation of the MIKE 11 model, predictive hydrological modeling was carried out based on the data of the WRF NMM mesoscale short-term weather forecast model and satisfactory results were obtained. The basis of the development of the method of forecasting the maximum flood water levels by the authors is the method of appropriate levels for the Tysa River, taking into account the data of automatic posts under different conditions of the formation and superimposition of flood waves along the river and its tributaries. The physical basis of the method of forecasting discharges and water levels in river sections is the Saint-Venant equation, which reflects the basic patterns of movement of river waves in a one-dimensional approximation. The essence of the method is to establish an empirical relationship between the appropriate levels (discharges) of water observed in the upper and lower reaches. The prematurity of the forecast is equal to the difference in the timing of the occurrence of such levels (discharges) in the specified creations. Thus, in order to warn about the negative consequences of passing the maximum water levels of floods of mountain rivers of Transcarpathia, which are caused by heavy precipitation or melting snow, it is carried out both when using modern prognostic mathematical models and when using the method of appropriate discharges or water levels.
Styles APA, Harvard, Vancouver, ISO, etc.
3

Bogning, Sakaros, Frederic Frappart, Fabien Blarel, Fernando Nino, Gil Mahe, Frederique Seyler, Jean-Jacques Braun, Raphael Onguene et Jacques Etame. « Estimating River Discharges in the Ogooue River Basin Using Satellite Altimetry Data ». Dans IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2018. http://dx.doi.org/10.1109/igarss.2018.8519574.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

MOSIEJ, Józef, et Teresa SUCHECKA. « THE ROLE OF IRRIGATION IN RIVER VALLEYS TO DEVELOP WATER QUALITY, PRODUCTION OF BIOMASS AND SUSTAINABLE RURAL DEVELOPMENT - CASE STUDY ». Dans RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.076.

Texte intégral
Résumé :
Ner river and its valley for over 170 years has been receiver for sewages from the city of Łódź. The natural system of this region (on the border of the watershed location, limitations of water supplies sources, lack of bigger natural rivers) in connection to city growth, lead to forming of specific system involving an agglomeration and water supplies system as well as wastewaters utilization system. The Ner river valley has the great potential to be effective in production biomass for energy purposes. Irrigation with polluted Ner river water cover fast growing plants high water and nutritional requirements. This would also work for the improvement of Ner river water quality. The achievement of good quality of water is not possible without irrigation of agricultural land in river valley. An amount of sewage discharged to Ner (193,017 m³ per day) several times higher then its natural flow in river. This is a result of strategy of water supply that is supported by transfer of water from Pilica river and underground water uptake for agglomeration. Relatively high runoff coefficient in years 1952 – 2011 was equal to 0.325 for Ner, in comparison to 0.17 for other rivers in Warta watershed. Despite the low natural flow Ner river discharges annually relatively high contaminants’ load to Warta river. In the analysed period (1995-2003) the annual average flow of Ner river amounted 10 % of annual average Warta river flow below its estuary. The share of analysed indicators of contaminants’ load approximated 27 % for total nitrogen, 37 % for phosphorus, 39 % for BOD5 and 28% for suspended solids. In the period 2004-2011 the annual average flow of Ner river amounted 13.8 % of annual average Warta river flow. The share of investigated pollutants loads consists 27.9 % for total nitrogen, 42.6 % for phosphorus, 19.8 % for BOD5 and 19.6 % for suspended solids.
Styles APA, Harvard, Vancouver, ISO, etc.
5

Chamoun, S., G. De et A. Schleiss. « Experimental investigation on turbidity current venting under restrained outflow discharges ». Dans The International Conference On Fluvial Hydraulics (River Flow 2016). Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742 : CRC Press, 2016. http://dx.doi.org/10.1201/9781315644479-227.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

Diermanse, F., J. Kwadijk, J. Beckers et J. Crebas. « Statistical trend analysis of River Rhine and Meuse discharges ». Dans BHS 3rd International Conference. British Hydrological Society, 2010. http://dx.doi.org/10.7558/bhs.2010.ic9.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

Miller, C. J., S. Kumar, S. Jasim et L. Schweitzer. « Hydraulic Modeling of PPCP Discharges in the Detroit River ». Dans World Water and Environmental Resources Congress 2005. Reston, VA : American Society of Civil Engineers, 2005. http://dx.doi.org/10.1061/40792(173)478.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Amsler, M., M. Blettler, I. Ezcurra de et J. Best. « Ecologic implications at a large junction of highly unequal discharges and sediment loads ». Dans The International Conference On Fluvial Hydraulics (River Flow 2016). Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742 : CRC Press, 2016. http://dx.doi.org/10.1201/9781315644479-266.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Holický, M., K. Jung et M. Sýkora. « Assessment of extreme discharges of the Vltava River in Prague ». Dans FLOOD RECOVERY, INNOVATION AND RESPONSE 2008. Southampton, UK : WIT Press, 2008. http://dx.doi.org/10.2495/friar080101.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Bačová Mitková, Veronika, et Dana Halmová. « ESTIMATION OF THE FLOOD MAXIMUM VOLUMES FOR VARIOUS DURATIONS OF THE RIVER RUNOFF AND THEIR MUTUAL DEPENDANCES : A CASE STUDY ON HRON RIVER IN SLOVAKIA ». Dans XXVII Conference of the Danubian Countries on Hydrological Forecasting and Hydrological Bases of Water Management. Nika-Tsentr, 2020. http://dx.doi.org/10.15407/uhmi.conference.01.17.

Texte intégral
Résumé :
This work deals with the determination of the annual maximum discharge volumes on the Hron River for the runoff time duration t = 2, 5, 10, and 20 days. The series of 84 years (1931–2015) mean daily discharges of the Hron River at Banská Bystrica station was used as input data to calculate the maximum annual volumes of runoff of the Hron River. Subsequently, the theoretical curves of exceedance of the maximal discharge volumes were determined by the LogPearson distribution of the Type III. This type of probability distribution is used to estimate maximum (extreme) values across a range of natural processes. The results of the estimated T-year volumes by using PL III distribution were compared to other types of theoretical distribution functions used in hydrological extreme analyses in Slovakia (Gamma, Log-normal, etc.). The second part of our work was focused on the bivariate modelling of the relationship between T-year maximum volumes with different duration and peak discharges. In the case of modelling without evaluating this mutual dependence of the flood wave characteristics, they may be overestimated (in the case of the negative dependence) or underestimated (in the case of the positive dependence). The Archimedean class of copula functions was used as mathematical tool for the dependence modelling. The LP III distribution was used as marginal probability distribution function. Subsequently joint and conditional return periods of the T-year maximum annual flows and T-year maximum volumes with different time duration were calculated. The first one defines joint return periods as: the return periods using one random variable equaling or exceeding a certain magnitude and/or using another random variable equaling or exceeding another certain magnitude. The second one is conditional return periods for one random variable, given that another random variable equals or exceeds a specific magnitude.
Styles APA, Harvard, Vancouver, ISO, etc.

Rapports d'organisations sur le sujet "River discharges"

1

Specht, W. L. Instream Biological Assessment of NPDES Point Source Discharges at the Savannah River Site, 2000. Office of Scientific and Technical Information (OSTI), juin 2001. http://dx.doi.org/10.2172/782224.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Becker, C. D. Feeding bionomics of juvenile chinook salmon relative to thermal discharges in the central Columbia River. Office of Scientific and Technical Information (OSTI), octobre 1994. http://dx.doi.org/10.2172/10188605.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Specht, W. L. Instream biological assessment of NPDES point source discharges at the Savannah River Site, 1997-1998. Office of Scientific and Technical Information (OSTI), février 2000. http://dx.doi.org/10.2172/752020.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

ARMY ENGINEER DISTRICT NEW ORLEANS LA. Stages and Discharges of the Mississippi River and Tributaries and Other Watersheds in New Orleans District for 1993. Fort Belvoir, VA : Defense Technical Information Center, janvier 1993. http://dx.doi.org/10.21236/ada362093.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Walshire, Lucas, Joseph Dunbar et Benjamin Breland. Stability analysis of Old River Low Sill Structure. Engineer Research and Development Center (U.S.), septembre 2022. http://dx.doi.org/10.21079/11681/45349.

Texte intégral
Résumé :
An updated stability analysis was performed on the Old River Low Sill Structure due to a change in the operating conditions from historic river sedimentation. Sedimentation of the Mississippi River channel since the 1973 spring flood has caused higher river stages at lower discharges. Numerical methods used included nonlinear analysis of pile group stability, seepage analyses, and limit equilibrium methods. The structure’s foundation was compromised during the 1973 flood, and emergency repairs were conducted to prevent scouring and undermining of the foundation by the flood scour. Rehabilitation included the reconstruction of a failed wing wall on the left abutment, rock and riprap fill in the forebay channel, and emergency grouting to fill the scour hole beneath the structure. An operating restriction was emplaced to limit the differential head across the structure due to flood damage. Taking these conditions into account, results from an updated analysis showed that full headwater uplift caused increased tension in the piles, while the increased body load caused increased compressive loads in the piles. Review of piezometric monitoring and the seepage analyses showed that full headwater uplift is unlikely, indicating the foundation grouting adequately sealed the scour hole beneath the structure. Analysis results exhibited lower magnitude compression and tension loads in the piles with design load cases compared to previous analyses. Recommendations from these analyses indicate that increased monitoring and additional investigation may support increasing the differential head limitation.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Buelt, J. L., W. Conbere, M. D. Freshley, R. J. Hicks, W. L. Kuhn, D. A. Lamar, R. J. Serne et J. L. Smoot. The predicted impacts to the groundwater and Columbia River from ammoniated water discharges to the 216-A-36B crib. Office of Scientific and Technical Information (OSTI), mars 1988. http://dx.doi.org/10.2172/5195541.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
7

ARMY ENGINEER DISTRICT NEW ORLEANS LA. Stages and Discharges of the Mississippi River and Tributaries and Other Watersheds in the New Orleans District for 1995. Fort Belvoir, VA : Defense Technical Information Center, janvier 1995. http://dx.doi.org/10.21236/ada362097.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

ARMY ENGINEER DISTRICT NEW ORLEANS LA. Stages and Discharges of the Mississippi River and Tributaries and Other Watersheds in the New Orleans District for 1994. Fort Belvoir, VA : Defense Technical Information Center, janvier 1994. http://dx.doi.org/10.21236/ada362753.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Tiffan, Kenneth F., Craig A. Haskell et Tobias J. Kock. Quantifying the Behavioral Response of Spawning Chum Salmon to Elevated Discharges from Bonneville Dam, Columbia River : Annual Report 2005-2006. Office of Scientific and Technical Information (OSTI), décembre 2008. http://dx.doi.org/10.2172/961851.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Jackson, D. G. Characterization Activities to Evaluate Chlorinated Solvent Discharges to Tims Branch from the A/M Area of the Savannah River Site. Office of Scientific and Technical Information (OSTI), février 2001. http://dx.doi.org/10.2172/775074.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
Vous pouvez également être intéressé par les bibliographies sur le sujet « River discharges » pour d’autres types de sources :
Articles de revues Thèses Livres
Nous offrons des réductions sur tous les plans premium pour les auteurs dont les œuvres sont incluses dans des sélections littéraires thématiques. Contactez-nous pour obtenir un code promo unique!

Vers la bibliographie