Proceedings of the 39th IAHR World Congress最新文献

{"title":"Impacts of climate change on the tourist-carrying capacity at La Playa beach (Sardinia, IT)","authors":"A. Sulis, G. Manca, Oumeima Yezza, S. Serreli","doi":"10.3850/iahr-39wc2521711920221876","DOIUrl":"https://doi.org/10.3850/iahr-39wc2521711920221876","url":null,"abstract":"","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"228 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122355838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical and physical modeling of Ponte Liscione (Guardial-fiera, Molise) dam spillways and stilling basin","authors":"M. Moroni, Myrta Castellino, P. De Girolamo","doi":"10.3850/iahr-39wc2521711920221465","DOIUrl":"https://doi.org/10.3850/iahr-39wc2521711920221465","url":null,"abstract":"Issues such as the design or reauditing of dams due to the occurrence of extreme events caused by climatic change are mandatory to address to ensure the safety of territories. These topics may be tackled numerically with Computational Fluid Dynamics and experimentally with physical models. This paper describes the 1:60 Froude-scaled numerical model of the Liscione (Guardialfiera, Molise, Italy) dam spillway and the downstream stilling basin. The k-ω SST turbulence model was chosen to close the Reynolds-averaged Navier–Stokes equations (RANS) implemented in the commercial software Ansys Fluent ®. The computation domain was discretized using a grid with hexagonal meshes. Experimental data for model validation were gathered from the 1:60 scale physical model of the Liscione dam spillways and the downstream riverbed of the Biferno river built at the Laboratory of Hydraulic and Maritime Constructions of the Sapienza University of Rome. The model was scaled according to the Froude number and fully developed turbulent flow conditions were reproduced at the model scale (Re > 10,000). From the analysis of the results of both the physical and the numerical models, it is clear that the stilling basin is undersized and therefore insufficient to manage the energy content of the fluid output to the river, with a significant impact on the erodible downstream river bottom in terms of scour depths. Furthermore, the numerical model showed that a less vigorous jet-like flow is obtained by removing one of the sills the dam is supplied with.","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127416644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydraulic characterization of low flow drip irrigation emitters used in intensive horticultural crops in Almeria (Spain)","authors":"M. Moreno-Pérez, Rafael Baeza-Cano, J. Roldán-Cañas, Gema Cánovas-Fernández, R. Reyes-Requena","doi":"10.5194/egusphere-egu21-2338","DOIUrl":"https://doi.org/10.5194/egusphere-egu21-2338","url":null,"abstract":"<p>In the present work, a selection of drip irrigation emitters used in greenhouse horticultural crops in the province of Almeria, Spain, were hydraulically evaluated, studying their hydraulic behavior and whether they meet with quality standards. Since manufacturers are offering lower flow emitters less spaced, all drippers tested are low flow. The hydraulic characterization will indicate the discharge and emission uniformity of the manufactured emitters, which are the fundamental parameters for the study of water use efficiency in drip irrigation. In the province of Almeria, water is a limiting factor due to the existence of a semi-arid climate, and, in addition, these limited water resources are used by intensive agriculture which causes a high consumption of these resources.</p><p>In total, 21 emitters have been evaluated, including all possible drippers according to their type of insertion (inline, pinched or online and interlinea), hydraulic behaviour (non-compensating and self-compensating) and, within the compensating ones, (anti-draining and non anti-draining). Its flow rates are between 1 and 2.4 l/h, except for a non-compensating interlina emitter of 3.8 l/h.</p><p>To carry out these tests, the criteria of the ISO 9261:2004 standard have been followed, calculating the coefficient of manufacturing variation and the emitter discharge equation on a test bench located in the La Mojonera Centre (Almeria) of the IFAPA (Andalusian Institute of Agricultural and Fishing Research and Training).</p><p>The results of this study show very good behavior in most of the emitters, and, as a consequence, a low coefficient of manufacturing variation has been obtained. The discharge equation obtained in the laboratory shows a low emisi&#243;n exponent in the self-compensating emitters, being, therefore, the compensation of the pressures very high in all cases. No statistically significant differences have been found between self-compensating and non-compensating emitters by analysing their manufacturing variation coefficients. Nor have any significant differences been found between self-compensating emitters according to whether they are anti-draining or non-anti-draining, considering also the coefficient of variation. In anti-draining emitters, all closing pressures are not satisfied according to the standard, and are exceeded with very high values. The opening pressure is met for two of the four emitters, and one of those that does not meet it does so with a very large value.</p>","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121361713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of anthropic changes on the propagation of the Gleno dam break wave in the Valle Camonica floodplain ","authors":"Riccardo Bonomelli, M. Pilotti, G. Fariña","doi":"10.5194/EGUSPHERE-EGU21-9983","DOIUrl":"https://doi.org/10.5194/EGUSPHERE-EGU21-9983","url":null,"abstract":"<p>The catastrophic flood following the Gleno dam break, which occurred in 1923, has been investigated in the literature (Pilotti et al., 2011, Milanesi and Pilotti, 2021) considering the 20 km long steep alpine valley separating the dam location from the hamlet of Corna. In this contribution, we investigate the propagation of the flood wave from Corna, where the computed hydrograph from previous investigation provides the upstream boundary condition, as far as the Lake Iseo outlet in Sarnico, where two controversial documents attest its effect on the lakeshore. In the middle, the flood crossed 30 km of a wide pre-alpine floodplain that has been deeply modified over the last century &#160;and crossed 25 km of a deep lake.</p><p>The simulation has been accomplished by coupling 2 different 2D solver of the Shallow Water Equations: the well-known HEC-RAS 2D software was used to cover the floodplain from Corna up to the Lake Iseo inlet, while a finite volume scheme was used to simulate the lake behaviour in response to the incoming flood. The finite volume scheme used to model the lake is based on the WAF solver developed by Toro (Toro, 2001) and further adapted to account for the geometry of lake Iseo using an unstructured mesh. The scheme used retains shock-capturing capabilities and well-balanced properties able to withstand the constantly changing bathymetry of the lake as well as the unsteadiness of the hydrodynamics modelled. As a first step, the simulation was performed on the topography derived from the LIDAR DTM surveyed in 2008-2009. A computational mesh was built with average grid size of 10 m aligned in correspondence of levees and other singularities. This first simulation dramatically shows how the propagation of the flood wave was affected by the presence of linear structures such as levees and road embankments, absent in 1923 as shown by historical maps. For this purpose, the linear structure that affect the flow was removed from the 2008-2009 DTM and a second simulation was performed in order to compare the different flow hydrograph at the inlet of the lake.</p><p>An important fallout of the modeling effort is the reconstruction of the 1923 original bathymetry of the river in Valle Camonica, to be compared with the present one, affected by 100 years of river training works. The comparison of the flood propagation using the two bathymetries highlights the consequences of systematic hydraulic works on the hazard distribution for the same event. Paradoxically, the residual risk is now much higher than 100 years ago. Moreover, the simulations show that the claim of a 50 cm high bore at the inlet of the Oglio river is unsubstantiated by the model results and that an important request of damages was probably based on a false statement.</p>","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122178556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic development of sediment infiltration in an artificial river bed","authors":"S. Haun, Assem Mayar, M. Noack, S. Wieprecht","doi":"10.5194/EGUSPHERE-EGU21-1603","DOIUrl":"https://doi.org/10.5194/EGUSPHERE-EGU21-1603","url":null,"abstract":"<div>\u0000<div>The infiltration and accumulation of fine sediments in gravel-bed rivers leads to a reduction of the existing pore space and may lead in a worst case to a complete clogging of the river bed. To understand the highly dynamic process of sediment infiltration, measurements with high temporal and spatial resolution are required. Within this study, the development of sediment accumulations in an artificial river bed is investigated to gain further understanding on the&#160; process of colmation. The artificial river bed, implemented in a research flume, is made of spheres with two different diameters and in different packing arrangements. Three sediment mixtures with different grain size distributions are supplied to observe the dynamic infiltration process, and to get information on the distribution over depth. In addition, supply rates and supply masses are varied during the experiments.</div>\u0000<div>&#160;</div>\u0000<div>To observe the dynamic development of sediment accumulation, the gamma-ray attenuation method is used, which provides the opportunity of non-intrusive and undisturbed continuous measurements during the experiments at a certain position. Additionally, the accumulated sediment masses are obtained right after the supply of sediments and 28 minutes later, with a high vertical resolution to detect changes as result of consolidation within the pores.</div>\u0000<div>&#160;</div>\u0000<div>From the measured amount of infiltrated sediments can be seen that the accumulated sediment mass is strongly particle size-dependent. The measurements of the fine sediment mixture show that the filling started from the bottom until the accumulation reach the surface of the artificial river bed. The experiments with the coarse sediment mixture resulted in a clogging layer in the upper section of the river bed, and subsequently less sediments reached the flume bed. By varying the supply rate, it can be seen that a higher supply rate leads to an earlier start of the infiltration and a rapid filling, while the lower supply rate resulted in a later infiltration and slow filling process. The measurements 28 minutes after the end of the experiments show, in addition, that dynamic changes happen mainly in the upper layers due to the washing of surface sediments by the flow, and only to a smaller extent by further settlements due to solidification within the pores. The feeding mass itself has no considerable effect on the infiltration behavior of the current setup, as once the pores are filled, almost no additional particles penetrate the bed.</div>\u0000<div>&#160;</div>\u0000<div>The use of a high sophisticated measurement method made it possible to investigate the infiltration process of sediments in an artificial river bed with high temporal and spatial resolution. Due to the use of different sediment mixtures, and different supply conditions, further insight on the process of fine sediment infiltration could be gained within this study.</div>\u0000</div><p>&#160;</p>","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130558644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights into fish-anthropogenic pressures relationships using machine learning techniques: the case of Castilla-La Mancha (Spain)","authors":"Carlotta Valerio, Graciela Gómez Nicola, Rocío Aránzazu Baquero Noriega, A. Garrido, L. De Stefano","doi":"10.5194/EGUSPHERE-EGU21-7119","DOIUrl":"https://doi.org/10.5194/EGUSPHERE-EGU21-7119","url":null,"abstract":"<p>Since 1970 the number of freshwater species has suffered a decline of 83% worldwide and anthropic activities are considered to be major drivers of ecosystems degradation. Linking the ecological response to the multiple anthropogenic stressors acting in the system is essential to effectively design policy measures to restore riverine ecosystems. However, obtaining quantitative links between stressors and ecological status is still challenging, given the non-linearity of the ecosystem response and the need to consider multiple factors at play. This study applies machine learning techniques to explore the relationships between anthropogenic pressures and the composition of fish communities in the river basins of Castilla-La Mancha, a region covering nearly 79 500 km&#178; in central Spain. During the past two decades, this region has experienced an alarming decline of the conservation status of native fish species. The starting point for the analysis is a 10x10 km grid that defines for each cell the presence or absence of several fish species before and after 2001. This database was used to characterize the evolution of several metrics of fish species richness over time, accounting for the species origin (native or alien), species features (e.g. pollution tolerance) and habitat preferences. Random Forest and Gradient Boosted Regression Trees algorithms were used to relate the resulting metrics to the stressor variables describing the anthropogenic pressures acting in the rivers, such as urban wastewater discharges, land use cover, hydro-morphological degradation and the alteration of the river flow regime. The study provides new, quantitative insights into pressures-ecosystem relationships in rivers and reveals the main factors that lead to the decline of fish richness in Castilla-La Mancha, which could help inform environmental policy initiatives.</p>","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126694317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new model for cross-shore surf and swash zone morphology evolution induced by nonlinear waves","authors":"T. Karambas, C. Koutitas","doi":"10.1061/(ASCE)0733-950X(2002)128:3(102)","DOIUrl":"https://doi.org/10.1061/(ASCE)0733-950X(2002)128:3(102)","url":null,"abstract":"Nonlinear wave transformation in the surf and swash zone is computed by a nonlinear breaking wave model based on the numerical solution of the Boussinesq-type equations. Instead of classical equations, higher-order equations in dispersion as well as in nonlinearity are derived and used inside and outside the surf zone. The Dibajnia and Watanabe transport rate formula involving unsteady aspects of the sand transport phenomenon is adopted for estimating sheet flow sediment transport rates as well as the bed load and suspended load over ripples. For the calculation of the suspended load induced by wave breaking, the Bailard formula is used after the consideration that the only dissipation mechanism is the wave breaking. Runup and rundown as well as sediment transport in the swash zone are incorporated in the model. The model is able to reproduce beach accretion and erosion without the use of an erosion/accretion criterion. The model is validated against large-scale experimental data.","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125980790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INFLUENCE OF VERTICAL FLUXES ON THE CLOGGING OF RIVERBED BY FINE SEDIMENT","authors":"Romain Dubuis, G. De Cesare","doi":"10.3850/iahr-39wc2521711920221145","DOIUrl":"https://doi.org/10.3850/iahr-39wc2521711920221145","url":null,"abstract":"","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114969860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of rainfall in the Upper Jeneberang River Basin, South Sulawesi, Indonesia","authors":"Ayuko Hirani Saleh, Akira Tai, M. P. Hatta, S. Yano","doi":"10.3850/iahr-39wc252171192022842","DOIUrl":"https://doi.org/10.3850/iahr-39wc252171192022842","url":null,"abstract":"","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115155547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Meta-analyzing Vertical slot fishways: what is the best design?","authors":"P. Branco, Ana Margarida Mascarenhas, Gonçalo Duarte, F. Romão, Susana Dias Amaral, M. T. Ferreira, A. Pinheiro, J. Santos","doi":"10.3850/iahr-39wc252171192022980","DOIUrl":"https://doi.org/10.3850/iahr-39wc252171192022980","url":null,"abstract":"","PeriodicalId":102126,"journal":{"name":"Proceedings of the 39th IAHR World Congress","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115166711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}