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This study presents a tracer technique based on the fluorescent properties of quinine to help on the visualization of shallow flows and allow a quantitative measurement of overland flow velocities. Laboratory experiments were conducted to compare the traditional dye tracer and thermal tracer techniques with this novel fluorescent (quinine) tracer by injecting a quinine solution and the other tracers into shallow flowing surface water. The leading-edge tracer velocities, estimated using videos of the experiments with the quinine tracer were compared with the velocities obtained by using thermograms and real imaging videos of the dye tracers. The results show that the quinine tracer can be used to estimate both overland and rill flow velocities, since measurements are similar to those resulting from using other commonly used tracers. The main advantage of using the quinine tracer is the higher visibility of the injected tracer under ultraviolet A (UVA) light for low luminosity conditions. In addition, smaller amounts of quinine tracer are needed than for dye tracers, which lead to smaller disturbances in the flow. It requires a simple experimental setup and is non-toxic to the environment.
João de Lima; Soheil Zehsaz; M. de Lima; Jorge Isidoro; Romeu Jorge; Ricardo Martins. Using Quinine as a Fluorescent Tracer to Estimate Overland Flow Velocities on Bare Soil: Proof of Concept under Controlled Laboratory Conditions. Agronomy 2021, 11, 1444 .
AMA StyleJoão de Lima, Soheil Zehsaz, M. de Lima, Jorge Isidoro, Romeu Jorge, Ricardo Martins. Using Quinine as a Fluorescent Tracer to Estimate Overland Flow Velocities on Bare Soil: Proof of Concept under Controlled Laboratory Conditions. Agronomy. 2021; 11 (7):1444.
Chicago/Turabian StyleJoão de Lima; Soheil Zehsaz; M. de Lima; Jorge Isidoro; Romeu Jorge; Ricardo Martins. 2021. "Using Quinine as a Fluorescent Tracer to Estimate Overland Flow Velocities on Bare Soil: Proof of Concept under Controlled Laboratory Conditions." Agronomy 11, no. 7: 1444.
Forest-fire rates have increased in Southern European landscapes. These fires damage forest ecosystems and alter their development. During the last few decades, an increase in fast-growing and highly fuel-bearing plant species such as bush, Eucalyptus globulus Labill., and Pinus pinaster Ait. has been observable in the interior of Portugal. This study aims to verify this assumption by the quantification of the biomass carbon sink in the forests of the Mação municipality. Maps of fire severity and forest biomass evolution after a wildfire event were produced for the period of 1991 to 2019. To quantify carbon retention in this region, this evolution was correlated with gross primary production (GPP) on the basis of satellite imagery from Landsat 5, Landsat 8, and MODIS MYD17A2H. Results show that wildfires in Mação increased in area and severity with each passing decade due to the large accumulation of biomass promoted by the abandonment of rural areas. Before the large fires of 2003, 2017, and 2019, carbon rates reached a daily maximum of 5.4, 5.3, and 4.7 gC/m2/day, respectively, showing a trend of forest-biomass accumulation in the Mação municipality.
Helena Fernandez; Fernando Granja-Martins; Celestina Pedras; Patrícia Fernandes; Jorge Isidoro. An Assessment of Forest Fires and CO2 Gross Primary Production from 1991 to 2019 in Mação (Portugal). Sustainability 2021, 13, 5816 .
AMA StyleHelena Fernandez, Fernando Granja-Martins, Celestina Pedras, Patrícia Fernandes, Jorge Isidoro. An Assessment of Forest Fires and CO2 Gross Primary Production from 1991 to 2019 in Mação (Portugal). Sustainability. 2021; 13 (11):5816.
Chicago/Turabian StyleHelena Fernandez; Fernando Granja-Martins; Celestina Pedras; Patrícia Fernandes; Jorge Isidoro. 2021. "An Assessment of Forest Fires and CO2 Gross Primary Production from 1991 to 2019 in Mação (Portugal)." Sustainability 13, no. 11: 5816.
Measuring and monitoring the water depth/level is a key issue when studying free-surface flows. These tasks are usually expensive in terms of time and money; however, even that expenditure is sometimes not enough to assure reliable and/or accurate results. Free-surface flows are complicated to deal with, as the instability caused by e.g., turbulence, wind, or air-entrainment, can cause important spatial and temporal fluctuations at the surface level. This work presents a non-intrusive, computer vision-based image treatment and segmentation technique that assures the detection and measurement of the free-surface water fluctuations along space and time. The laboratory physically based tests under steady flow conditions, and different channel bed roughness and slopes, showed a very good fit with manually direct measurements carried out with a point-gauge micrometre. Under unsteady flow conditions this technique also showed to successfully deal with applications requiring high spatiotemporal resolution of water depth/level measurements.
Jorge M.G.P. Isidoro; Ricardo Martins; Rita F. Carvalho; João L.M.P. de Lima. A high-frequency low-cost technique for measuring small-scale water level fluctuations using computer vision. Measurement 2021, 180, 109477 .
AMA StyleJorge M.G.P. Isidoro, Ricardo Martins, Rita F. Carvalho, João L.M.P. de Lima. A high-frequency low-cost technique for measuring small-scale water level fluctuations using computer vision. Measurement. 2021; 180 ():109477.
Chicago/Turabian StyleJorge M.G.P. Isidoro; Ricardo Martins; Rita F. Carvalho; João L.M.P. de Lima. 2021. "A high-frequency low-cost technique for measuring small-scale water level fluctuations using computer vision." Measurement 180, no. : 109477.
Urbanization leads to changes in the surface cover that alter the hydrological cycle of cities, particularly by increasing the impervious area and, thereby, reducing the interception, storage and infiltration capacity of rainwater. Nature-based solutions (NBS) can contribute to flood risk mitigation in urbanized areas by restoring hydrological functions. However, the effects of NBS on flood risk mitigation are complex and can differ substantially with the type of the NBS. Therefore, the effectiveness of NBS at the urban catchment scale is still subject to much debate, especially at the scale of urban catchments. In this study, the effects of different NBS on urban flood mitigation were evaluated for the city of Eindhoven in The Netherlands, as it has a history of urban flood events. To this end, various NBS scenarios were defined by municipal stakeholders and their impacts modelled with the numerical model Infoworks ICM. This was done for design storms with short, medium and long return periods (5, 10 and 100 years). Overall, the simulated NBS were effective in flood risk mitigation, reducing the flooded area as well as flood depth. The effectiveness of the individual NBS scenarios, however, depended strongly on the location and extension of the NBS, as well as on storm intensity. The effectiveness tended to increase with the increase in NBS surface area, while it tended to decrease with increasing storm intensity and, hence, return period. The NBS solution increasing street water storage was revealed to be more effective than those involving green car parks and green roofs. This study showed that numerical flooding models can be useful tools to assess the effects of NBS to reduce flood extent, water depth and/or velocity, providing insights that can support city planners to design and compare alternative strategies and plans for urban flood risk mitigation.
Sandra Costa; Rik Peters; Ricardo Martins; Luuk Postmes; Jan Keizer; Peter Roebeling. Effectiveness of Nature-Based Solutions on Pluvial Flood Hazard Mitigation: The Case Study of the City of Eindhoven (The Netherlands). Resources 2021, 10, 24 .
AMA StyleSandra Costa, Rik Peters, Ricardo Martins, Luuk Postmes, Jan Keizer, Peter Roebeling. Effectiveness of Nature-Based Solutions on Pluvial Flood Hazard Mitigation: The Case Study of the City of Eindhoven (The Netherlands). Resources. 2021; 10 (3):24.
Chicago/Turabian StyleSandra Costa; Rik Peters; Ricardo Martins; Luuk Postmes; Jan Keizer; Peter Roebeling. 2021. "Effectiveness of Nature-Based Solutions on Pluvial Flood Hazard Mitigation: The Case Study of the City of Eindhoven (The Netherlands)." Resources 10, no. 3: 24.
Monitoring water levels is fundamental in a variety of fields within geosciences, hydraulics, and hydrology. Examples of this can be found in the field in rivers, reservoirs, or surface runoff while, at a much lower scale, in the laboratory, e.g., open channel flow. This is an area of great complexity, due to the large diversity of spatial and temporal scales of hydraulic systems and phenomena such as the non-linearity of fluid mechanics, sediment or pollutant transport, turbulence, the interactions between water and solid surfaces (natural or artificial), or atmospheric boundary conditions. The last decade has brought important advances in techniques associated with the acquisition and analysis of images, techniques encompassed in what is currently called “computer vision”.
In this work, a methodology based on image treatment and segmentation techniques was developed, which allows the detection of the free flow water surface over time in laboratory conditions using simple video equipment.
The objective of this work was to develop and validate an algorithm for detecting the free water surface with high temporal resolution. Other specific objectives were: (i) to validate the algorithm against measurements in a steady-state flow; (ii) to test the algorithm for accentuated oscillations of the free surface resulting from different bed geometries, slope, and discharge; and (iii) to assert the feasibility of the systematic use of non-specialized and inexpensive video equipment as a level measuring device, without compromising its accuracy.
All laboratory work took place at the Laboratory of Hydraulics, Water Resources and Environment of the Department of Civil Engineering of the Faculty of Sciences and Technology of the University of Coimbra. The channel has dimensions of 4.00m × 0.15m (L×W) and the slope is adjustable. Water is supplied to the channel, in a closed circuit, from a reservoir by means of a pump and piping system, and the flow controlled by a ball valve. The algorithm developed for detecting the free surface is based on the acquisition, treatment, analysis, and segmentation of images. MATLAB® was used to code functions to recognize the edges present in an image by the image intensity gradient as well as the best-defined segment present in the image, which, in this case, corresponds to the free water surface.
Jorge Isidoro; Ricardo Martins; João de Lima. Using computer vision to monitor varying water levels: an exploratory laboratory experience. 2021, 1 .
AMA StyleJorge Isidoro, Ricardo Martins, João de Lima. Using computer vision to monitor varying water levels: an exploratory laboratory experience. . 2021; ():1.
Chicago/Turabian StyleJorge Isidoro; Ricardo Martins; João de Lima. 2021. "Using computer vision to monitor varying water levels: an exploratory laboratory experience." , no. : 1.
Recently burnt areas across the world have been documented to produce strong to extreme runoff and erosion responses. At the same time, they are well known to lose their typically blackish colour due to wildfire ashes (sensu latu, including char) relatively quickly during the early phases of the window-of-disturbance. The contribution of wildfire ash to post-fire erosion rates, however, remains poorly quantified. Arguably, this is first and foremost due to the difficulties of separating the ash and char fractions from the mineral soil fractions, at least at the routinely basis that is required for field erosion studies with high temporal resolution (say, less than 1 month) and an absolute minimum of three replicate plots per slope or treatment. To this end, the national ASHMOB project (CENTRO-01-0145-FEDER-029351) is trying to advance the knowledge of the mobilization of wildfire ash by wind and water erosion by studying it first under controlled laboratory conditions. The present study concerns the first phase of wildfire ash erosion by water, using Morgan cups to quantify the splash erosion of wildfire ash by high-intensity simulated rainfall in the Laboratory of Hydraulics, Water Resources and Environment of the University of Coimbra. More specifically, this study assessed the importance of the following factors in ash splash erosion: (1) extreme rainfall intensities, ranging from 150 to 450 mm/h; (2) source of the ash, from recently burnt woodlands dominated by maritime Pinus pinaster, Eucalyptus globulus, and Arbutus unedo; (3) ash depth or load. Preliminary analysis of the obtained results suggested that splash erosion of wildfire ash: (1) varied strongly with the applied rainfall intensity, increasing in a linear manner with increasing intensity; (2) differed markedly with the dominant tree cover, being clearly lower for the pine and eucalypt stands than for the strawberry tree stands, possibly due to the differences in soil burn severity as indicated by blackish and whitish ashes, respectively; (3) depended noticeably on ash depth, decreasing clearly with increasing ash depth and, arguably, with a greater damping capacity.
Ricardo Martins; Jacob Keizer; João R.C.B. Abrantes; Oscar González-Pelayo; Isabel Pedroso de Lima; João Luis M. Pedroso de Lima. Wildfire ash mobilization by splash under simulated rainfall in controlled laboratory conditions. 2021, 1 .
AMA StyleRicardo Martins, Jacob Keizer, João R.C.B. Abrantes, Oscar González-Pelayo, Isabel Pedroso de Lima, João Luis M. Pedroso de Lima. Wildfire ash mobilization by splash under simulated rainfall in controlled laboratory conditions. . 2021; ():1.
Chicago/Turabian StyleRicardo Martins; Jacob Keizer; João R.C.B. Abrantes; Oscar González-Pelayo; Isabel Pedroso de Lima; João Luis M. Pedroso de Lima. 2021. "Wildfire ash mobilization by splash under simulated rainfall in controlled laboratory conditions." , no. : 1.
Recently burnt areas across the world have been documented to produce strong to extreme erosion responses but these responses are much better quantified for (micro-)plots and planar hillslopes than for convergent hillslopes and catchments. The same applies, mutatis mutandis, for the effectiveness of so-called emergency stabilization measures to reduce the risks of such strong to extreme responses. The only prior study in Portugal on the mitigation of post-fire erosion beyond the planar slope scale (i.e. swales of 500-800 m2) tested mulching with eucalypt logging residues. It found the treatment to be highly effective during the first two post-fire hydrological years in the sense that soil losses were, average, 88 and 77% smaller at the three mulched swales than at the 3 untreated swales. This in spite the mulch had been applied at reduced rate (2.4 Mg ha-1) compared to preceding, plot-scale studies in the region (>8 Mg ha-1). Against this background, the present study decided to test the effectiveness of log barriers to reduce post-fire erosion beyond the planar slope scale, in particular to provide evidence supporting the post-fire land management strategy that is being developed by the INTERREG-SUDOE project EPyRIS (SOE2/P5/E0811). The study area is located in the Aveiro District of central Portugal and burnt during early September 2020. In the part of the burnt area that is being managed by the Portuguese Nature Conservation and Forests Institute (ICNF), three pairs of neighbouring micro-catchments of 0.3-0.8 ha and, in one exceptional case (due to run-on from a forest track), 2.7 ha were instrumented with sediment fences at their outlets before the occurrence of the first significant rainfall event after the wildfire. The barriers, however, could not be installed until after the subtropical storm ALPHA that hit continental Portugal on 18-19 September, also due to some delay in the contracting of a company that would have prior experience in implementing post-fire emergency stabilization measures. The sediment yields produced by this first post-fire rainfall event were used to select which of each pair of micro-catchments to be treated, i.e. the one producing most erosion. Furthermore, the initial sediment yields of the three to-be-treated micro-catchments were used to decide the number of barriers per catchment, ranging from one to three. Both these aspects of the experimental design imply that the quantification of (cost-)effectiveness will less straightforward than in case of a randomized design. In compensation, the upslope part of each barrier was covered with geotextile immediately after construction to estimate the barrier’s capacity to induce sediment deposition and, at the scale of the entire micro-catchment, its effectiveness to reduce post-fire sediment yields, even if sediment deposition will only be measured at the end of each hydrological. This envisaged poster will present the differences in sediment yields between the paired, treated and untreated micro-catchments during the first post-fire autumn-winter period, and discuss them in function of terrain characteristics of the micro-catchments, RS-based fire severity, rainfall regime and changes in surface cover as derived from RGB imagery acquired with a low-cost drone.
Jan Jacob Keizer; Joana Silva; Mathijs Augustijn; Ricardo Martins; Martinho Martins; Marta Basso; Antonio Girona-García; Liliana Simões; Diana Vieira. Mitigation of post-fire erosion from terraced micro-catchments using timber barriers. 2021, 1 .
AMA StyleJan Jacob Keizer, Joana Silva, Mathijs Augustijn, Ricardo Martins, Martinho Martins, Marta Basso, Antonio Girona-García, Liliana Simões, Diana Vieira. Mitigation of post-fire erosion from terraced micro-catchments using timber barriers. . 2021; ():1.
Chicago/Turabian StyleJan Jacob Keizer; Joana Silva; Mathijs Augustijn; Ricardo Martins; Martinho Martins; Marta Basso; Antonio Girona-García; Liliana Simões; Diana Vieira. 2021. "Mitigation of post-fire erosion from terraced micro-catchments using timber barriers." , no. : 1.
Rainfall simulation experiments are widely used in soil science, geomorphology and hydrology research and teaching. Such experimental setups are particularly important in the study of rainfall-runoff, erosion and pollutant transport processes. Rainfall simulators have been applied within laboratory- and field-based studies and have the advantage of enabling controlled and reproducible rainfall events of varying intensity, duration and drop spectra. The flexibility and adaptability of rainfall simulators to examine diverse research applications of varying temporal and spatial scales means that hundreds of tailor-made rainfall simulator setups can be identified across the literature. Although it is beneficial for researchers to adapt their experimental designs to suit their specific research objectives, the diversity in the type, sizing, form, operation and methodologies of rainfall simulators ultimately results in complications when comparing results and outputs obtained between studies.
Currently, comparisons between studies can be very difficult, if not impossible, as the different measurement methods, artificial rainfall event characteristics and test conditions result in considerable difficulties when benchmarking results and findings obtained from rainfall simulation experiments. We recommend that the scientific community should establish a set of methodological procedures aimed at harmonising basic procedures in rainfall simulator-based studies in the fields of hydrological and geomorphological sciences. This would ensure that results obtained from different rainfall simulator studies and setups are harmonised, regulated and comparable. On the one hand, this process involves harmonising rainfall simulators design characteristics, whereas further steps should focus on measurement methods and metrics so results can be more readily compared.
This presentation highlights the inherit problems in benchmarking and comparing studies at present due to large variations in the way that researchers and institutions assess and quantify rainfall simulator performance and present results. Some degree of ‘standardisation’ of rainfall simulator approaches is needed. However, standardising approaches used within rainfall simulation does not allow researchers to adapt their experimental setups to suit their specific research needs, which is one of the key benefits of using rainfall simulators. Instead, ‘harmonisation’ (i.e. ensuring that the scientific community develop a set of regulated and comparable methodological procedures and best practices for use in rainfall simulator studies whilst still allowing some degree of adaptability for specific research practices) is required. Here we present a series of harmonisation procedures, which should be developed to ensure that rainfall simulators are designed and constructed to allow for harmonisation, as well as suggesting a series of steps towards harmonising the methods and metrics used to quantify and compare experimental results.
With these objectives in mind, we aim to stimulate the discussion and enhance understanding of the difficulties and requirements of rainfall simulator based experimental research, namely by creating a platform that embraces and consults the International research community across multiple research facilities and institutes. This presentation will kick-start discussions (via web seminar sessions beginning in Summer 2021) leading up to a future international symposium addressing and acting upon these issues and disseminating the findings of this consultation period (Spring/Summer 2022 in Coimbra, Portugal). Everyone is invited to join this step towards harmonisation in rainfall simulation.
Thomas Iserloh; Jorge M. G. P. Isidoro; João L. M. P. de Lima; Miriam Marzen; M. Isabel P. de Lima; Daniel Green; Manuel Seeger; Johannes B. Ries. Moving towards harmonisation in rainfall simulation. 2021, 1 .
AMA StyleThomas Iserloh, Jorge M. G. P. Isidoro, João L. M. P. de Lima, Miriam Marzen, M. Isabel P. de Lima, Daniel Green, Manuel Seeger, Johannes B. Ries. Moving towards harmonisation in rainfall simulation. . 2021; ():1.
Chicago/Turabian StyleThomas Iserloh; Jorge M. G. P. Isidoro; João L. M. P. de Lima; Miriam Marzen; M. Isabel P. de Lima; Daniel Green; Manuel Seeger; Johannes B. Ries. 2021. "Moving towards harmonisation in rainfall simulation." , no. : 1.
In the near future, a higher occurrence of wildfires is expected due to climate change, carrying social, environmental, and economic implications. Such impacts are often associated with an increase of post‐fire hydrological and erosive responses, which are difficult to predict. Soil erosion models have been proven to be a valuable tool in the decision‐making process, from emergency response to long‐term planning, however, they were not designed for post‐fire conditions, so they need to be adapted to include fire‐induced changes. In the recent years, there has been an increasing number of studies testing different models and adaptations for the prediction of post‐fire soil erosion. However, many of these adaptations are being applied without field validation or model performance assessment. Therefore, this study aims to describe the scientific advances in the last twenty years in post‐fire soil erosion modelling research and evaluate model adaptations to burned areas that aim to include: i) fire‐induced changes in soil and ground cover, ii) fire‐induced changes in infiltration, iii) burn severity, and iv) mitigation measures in their predictions. This study also discusses the strengths and weaknesses of those approaches, suggests potential improvements, and identifies directions for future research. Results show that studies are not homogeneously distributed worldwide, neither according to the model type used, nor by regions most affected by wildfires. During calibration, 73% of the cases involved model adaptation to burned conditions, and only 21% attempted to accommodate new processes. Burn severity was addressed in 75% of the cases, whilst mitigation measures were simulated in 27%. Additionally, only a minor percentage of model predictions were validated with independent field data (17%) or assessed for uncertainties (13%). Therefore, further efforts are required on the adaptation of erosion models to burned conditions to be widely used for post‐fire management decision.
A.R. Lopes; A. Girona‐García; S. Corticeiro; R. Martins; J.J. Keizer; D.C.S. Vieira. What is wrong with post‐fire soil erosion modelling? A meta‐analysis on current approaches, research gaps, and future directions. Earth Surface Processes and Landforms 2020, 46, 205 -219.
AMA StyleA.R. Lopes, A. Girona‐García, S. Corticeiro, R. Martins, J.J. Keizer, D.C.S. Vieira. What is wrong with post‐fire soil erosion modelling? A meta‐analysis on current approaches, research gaps, and future directions. Earth Surface Processes and Landforms. 2020; 46 (1):205-219.
Chicago/Turabian StyleA.R. Lopes; A. Girona‐García; S. Corticeiro; R. Martins; J.J. Keizer; D.C.S. Vieira. 2020. "What is wrong with post‐fire soil erosion modelling? A meta‐analysis on current approaches, research gaps, and future directions." Earth Surface Processes and Landforms 46, no. 1: 205-219.
Rainfall simulation is widely used within hydrological and geomorphological sciences and is particularly important in the study of rainfall-runoff, erosion and pollutant transport processes. Rainfall simulators have been applied within laboratory- and field-based studies and have the advantages of enabling controlled and reproducible rainfall event characteristics in relation to rainfall intensity, duration, and drop spectra. The flexibility and advantages of using rainfall simulators to study a wide range of research objectives has resulted in significant diversity in the type, sizing, form, operation and methodologies of rainfall simulators, and an extensive review of rainfall simulator research has led to more than 250 different rainfall simulator setups being identified in the literature. Rainfall simulators come in all different shapes and sizes!
The adaptability of rainfall simulators to study a wide range of research areas of varying scale ultimately results in several issues when comparing results and outputs obtained from different simulator setups. In fact, comparisons between studies can be very difficult, if not impossible, as the different measurement methods, artificial rainfall event characteristics and test conditions result in considerable difficulties when benchmarking results and findings obtained from rainfall simulation experiments. Thus, the scientific community should establish set methodological procedures to allow comparisons between results obtained from different rainfall simulator setups. Harmonization of basic procedures in rainfall simulator based studies in the fields of hydrological and geomorphological sciences would ensure that results between different rainfall simulator studies are comparable, standardised and regulated. The first step in this process involves standardising rainfall simulators design characteristics, whereas further steps should focus on measurement methods and metrics so results can be compared.
This paper aims to bring together current understanding on the use of rainfall simulators within hydrological and geomorphological research, and provide a platform to discuss and enhance understanding of the requirements on the standardisation of rainfall simulator based experimental research. This paper also aims to establish an international research community focused on advancing standardisation in rainfall simulation based at different research facilities and institutes, and will kick-start discussions leading up to a future international symposium dealing with these issues (date TBC). Everyone is invited to join this (small) step towards standardisation in rainfall simulation!
Jorge Isidoro; Ian Pattison; Thomas Iserloh; João De Lima; Daniel Green; Miriam Marzen; Isabel De Lima; Alexandre Silveira; Ross Stirling. A (small) step towards standardisation in rainfall simulation experiments. 2020, 1 .
AMA StyleJorge Isidoro, Ian Pattison, Thomas Iserloh, João De Lima, Daniel Green, Miriam Marzen, Isabel De Lima, Alexandre Silveira, Ross Stirling. A (small) step towards standardisation in rainfall simulation experiments. . 2020; ():1.
Chicago/Turabian StyleJorge Isidoro; Ian Pattison; Thomas Iserloh; João De Lima; Daniel Green; Miriam Marzen; Isabel De Lima; Alexandre Silveira; Ross Stirling. 2020. "A (small) step towards standardisation in rainfall simulation experiments." , no. : 1.
RESUMO O estudo do escoamento superficial e transporte de poluentes é de grande importância, pois ajuda na prevenção de impactos ambientais, auxiliando em planejamentos a serem realizados pelo poder público. Neste trabalho, teve-se como objetivo estudar, em laboratório, a dinâmica do transporte de material (cloreto de sódio - NaCl) disposto sobre uma superfície impermeável, dissolvido pela aplicação de água via simulador de chuva, tendo como fonte de variação três variáveis independentes: declividade, intensidade de precipitação e posição do material. Utilizou-se o delineamento experimental de faces centradas, que contemplou diferentes cenários reproduzidos nos experimentos, onde se avaliou a influência das três variáveis independentes sobre às dependentes (tempo de transporte, valor de pico, tempo de pico e massa total transportada), cujas respostas foram monitoradas no exutório do modelo experimental. A análise de resultados obtidos permitiu identificar o efeito significativo da declividade e posição do material sobre todas as variáveis dependentes estudadas e ainda o efeito quadrático da declividade para o tempo de transporte e a massa total transportada. Já para a intensidade de precipitação, verificou-se influência apenas para o tempo de transporte, dentro dos intervalos de estudo com nível de significância de 95%. O modelo produzido para o tempo de transporte é capaz de explicar 90% da variabilidade dos dados, enquanto o para o valor de pico possui uma capacidade de explicação de 67,9%. O tempo de pico possui um modelo capaz de explicar 74,2% da variabilidade dos dados, e o modelo produzido para a massa total transportada possui uma capacidade de explicação de 62,4% da variabilidade dos dados.
Bruna Peterson Luque Pessoti; Alexandre Silveira; Rafael Brito De Moura; Jorge Manuel Guieiro Pereira Isidoro; Rafael De Oliveira Tiezzi; Flávio Aparecido Gonçalves. Transporte de material dissolvido em superfície impermeável sob chuva artificial analisado com a aplicação do delineamento experimental das faces centradas. Engenharia Sanitaria e Ambiental 2020, 25, 97 -106.
AMA StyleBruna Peterson Luque Pessoti, Alexandre Silveira, Rafael Brito De Moura, Jorge Manuel Guieiro Pereira Isidoro, Rafael De Oliveira Tiezzi, Flávio Aparecido Gonçalves. Transporte de material dissolvido em superfície impermeável sob chuva artificial analisado com a aplicação do delineamento experimental das faces centradas. Engenharia Sanitaria e Ambiental. 2020; 25 (1):97-106.
Chicago/Turabian StyleBruna Peterson Luque Pessoti; Alexandre Silveira; Rafael Brito De Moura; Jorge Manuel Guieiro Pereira Isidoro; Rafael De Oliveira Tiezzi; Flávio Aparecido Gonçalves. 2020. "Transporte de material dissolvido em superfície impermeável sob chuva artificial analisado com a aplicação do delineamento experimental das faces centradas." Engenharia Sanitaria e Ambiental 25, no. 1: 97-106.
Urbanization affects runoff processes and sediment transport, but the magnitude of the impacts remains poorly understood. Different spatial patterns of pervious and impervious surfaces influence flow and sediment connectivity between hillslopes and stream networks. Following years of research on the peri-urbanizing Ribeira dos Covões catchment in Portugal, this study uses laboratory rainfall simulation experiments to better assess the impact of soil and pavement patterns on runoff (amount, runoff start and stop times) and sediment transport. Based on urban cores observed in the study catchment, the investigation focused on seven spatial patterns: bare soil (S), 100% pavement (P), and 60% pavement under continuous - C - surface placed upslope (CU) and downslope (CD), and dispersed - D - over the surface with regular (DR), irregular (DI) and linear (DL) distribution. A 1.00 m × 1.00 m flume, 0.05 m deep with a 9° slope, facilitated the experiments. The study used sandy-loam soil (1500 kg m−3) with concrete slabs representing pavement. Each experiment comprised a series of four rainfall simulations, each lasting 20 min (50 mm h−1), separated by 30-min intervals, to assess the impact of different initial soil moisture conditions. Results indicate that both spatial pattern and soil moisture drive runoff. Under dry conditions, CD provides runoff that is 7 times faster and about 4% higher than that for CU. Already wet conditions, however, produced 12% more runoff on CU than on CD. The greater runoff arose from faster soil saturation, driven by soil moisture increasing more quickly during the rainfall, as well as upstream runoff from paved surfaces, though runoff took longer to reach the outlet. The dispersed pavement pattern only affected runoff amount, with DL producing the highest coefficients (40–71%) and DI the lowest (25–55%), since longer flow paths increase the opportunities for water infiltration. Additionally, CU yielded 40% more sediment transport than CD, but the three dispersed patterns did not show a significant impact (p > 0.05). The results suggest that appropriate planning can reduce flood hazard and land degradation in urban areas, in particular by using dispersed patterns of sealed surfaces to enhance water infiltration and retention.
C.S.S. Ferreira; R. Moruzzi; Jorge Isidoro; M. Tudor; M. Vargas; Antonio Ferreira; J.L.M.P. de Lima. Impacts of distinct spatial arrangements of impervious surfaces on runoff and sediment fluxes from laboratory experiments. Anthropocene 2019, 28, 100219 .
AMA StyleC.S.S. Ferreira, R. Moruzzi, Jorge Isidoro, M. Tudor, M. Vargas, Antonio Ferreira, J.L.M.P. de Lima. Impacts of distinct spatial arrangements of impervious surfaces on runoff and sediment fluxes from laboratory experiments. Anthropocene. 2019; 28 ():100219.
Chicago/Turabian StyleC.S.S. Ferreira; R. Moruzzi; Jorge Isidoro; M. Tudor; M. Vargas; Antonio Ferreira; J.L.M.P. de Lima. 2019. "Impacts of distinct spatial arrangements of impervious surfaces on runoff and sediment fluxes from laboratory experiments." Anthropocene 28, no. : 100219.
The South of the Iberian Peninsula is subject to long periods of drought followed by heavy rain events over shallow soils, promoting soil loss. The Modified Fournier Index (MFI) is a good indicator of this process; however, MFI is sometimes difficult to assess due to the scarcity of rainfall data. This study proposes a methodology using MFI and supported by a geographic information system (GIS) and geostatistics to map rainfall aggressiveness with scarce spatial rainfall data, where physiographic variables are used to overcome the lack of rainfall data. The Grândola Mountain Range in the Alentejo region, Portugal, is presented as a case study. This area is a CORINE biotope, currently under application to the Natura 2000 network, and should be considered as a priority for the conservation of the environment. The model allowed us to create a map of rainfall aggressiveness, classified according to CORINE-CEC, found to be Moderate in the mountains and Low in the coastal area of the Grândola Mountain Range. This cartography is an important tool for local and national stakeholders and authorities with responsibilities in planning and protection of the territory. The methodology can be used in regions with scarce spatial rainfall data to assess areas susceptible to rainfall-induced soil erosion.
H. Fernandez; Fernando Martins; Jorge M. G. P. Isidoro. Mapping rainfall aggressiveness from physiographical data: application to the Grândola Mountain Range (Alentejo, Portugal). Physical Geography 2019, 41, 451 -466.
AMA StyleH. Fernandez, Fernando Martins, Jorge M. G. P. Isidoro. Mapping rainfall aggressiveness from physiographical data: application to the Grândola Mountain Range (Alentejo, Portugal). Physical Geography. 2019; 41 (5):451-466.
Chicago/Turabian StyleH. Fernandez; Fernando Martins; Jorge M. G. P. Isidoro. 2019. "Mapping rainfall aggressiveness from physiographical data: application to the Grândola Mountain Range (Alentejo, Portugal)." Physical Geography 41, no. 5: 451-466.
It is widely accepted that urbanization modifies the hydrological processes, increasing runoff and flood hazard. However, after decades of research, the magnitude of the impacts is not well understood. This is partially due to spatial-temporal differences in rainfall-runoff processes over complex landscapes comprising different land-uses, typical of peri-urban areas. This study aims to investigate the impact of different spatial patterns of pavement on surface runoff, under distinct weather conditions (dry vs wet). Inspired on urban cores observed in peri-urban catchments, 7 spatial patterns were investigated: 100% pavement, 100% pervious, and 60% pavement (and 40% pervious) under continuous placement located upslope or downslope, and under dispersed patterns with regular, irregular and linear distribution. Concrete blocks were used as pavement material, whereas pervious surfaces were simulated using either bare soil, 1.5 kg·m−3 with sandy-loam texture, or commercial natural grass carpets. The 13 configurations of pavement and pervious materials, pavement-soil and pavement-grass were simulated in the laboratory, in a 1.0 × 1.0 m2 flume, with 0.05 m soil depth and 9° slope. Three rainfall simulation experiments were performed for each spatial configuration. Each experiment comprises a set of four sequential storms with 50 mm·h−1 over 20-min, interrupted by 30-min intervals, to simulate dry and increasingly wet antecedent settings. Results show that runoff is driven by both spatial pattern and soil moisture. Runoff coefficients ranged from 70–81% in fully paved surfaces to 1.4–40% in bare soil and 0.2–3.8% in grass, exhibiting increasing values from dry to wet antecedent moisture conditions, especially in bare soil. Under dry conditions, continuous pavement generates more runoff if placed downslope than upslope (28% vs 5% with grass and 37% vs 33% with bare soil). Under wet settings, however, continuous pavement generated (i) higher runoff if associated with downslope than upslope bare soil (63% vs 52%), due to saturation-excess favored by cumulative rainfall and upslope runoff; and (ii) lower runoff if associated with downslope than upslope grass surface (33% vs 24%). When considering dispersed pavement, runoff increased from dry to wet conditions, ranging from 32% to 62% and 1.3% to 23% when distributed with soil and grass covers, respectively. Adequate urban planning based on spatial patterns that maximize runoff sinks over the landscape should be considered to enhance urban flood resilience. Grass (as other covers) has higher capacity to retain and infiltrate rainfall and runoff than bare soil, and may represent a nature-based solution to mitigate flood hazard in peri-urban areas.
Ferreira; Romeu Gerardo; Jorge Isidoro; Rodrigo Moruzzi; João De Lima. Impact οf Pavement Distribution οn Hillslope Runoff ιn Peri-Urban Landscapes, Based οn Laboratorial Experiments. Proceedings 2019, 30, 10 .
AMA StyleFerreira, Romeu Gerardo, Jorge Isidoro, Rodrigo Moruzzi, João De Lima. Impact οf Pavement Distribution οn Hillslope Runoff ιn Peri-Urban Landscapes, Based οn Laboratorial Experiments. Proceedings. 2019; 30 (1):10.
Chicago/Turabian StyleFerreira; Romeu Gerardo; Jorge Isidoro; Rodrigo Moruzzi; João De Lima. 2019. "Impact οf Pavement Distribution οn Hillslope Runoff ιn Peri-Urban Landscapes, Based οn Laboratorial Experiments." Proceedings 30, no. 1: 10.
Changes in the climate system and the hydrologic regime strongly affect all water uses and human activity. The main goal of this study is to evaluate the impact of rainfall pattern change on streamflow for 26 Brazilian basins with hydropower plants. More precisely, the goal is to estimate the trends on average streamflow for the 2011–2100 period. The estimated trends result from the analysis of rainfall obtained from a possible climate scenario, among others. The annual average streamflow for this 90-year period is simulated and compared with records from 83 years of observations (1931–2013). Simulations were carried out using two rainfall-to-streamflow hydrological models: Soil Moisture Accounting Procedure (SMAP) and Stochastic Linear Model (SLM). Results from simulations show important impacts, namely, an increase of streamflow in the southern basins and a decrease in the northern basins. Such changes can lead to disastrous consequences, considering the historical exposure to floods and droughts in the southern and northeast regions, respectively. These findings, in addition to the recent severe drought events that have occurred in such regions, provide awareness of a new cycle of reform to the existing water policies and Brazilian institutional framework, which saw the completion of its first 20 years in 2017.
Rafael O. Tiezzi; Paulo S. F. Barbosa; João E. G. Lopes; Alberto L. Francato; Renato C. Zambon; Alexandre Silveira; Paulo H. B. J. Menezes; Jorge M. G. P. Isidoro. Trends of streamflow under climate change for 26 Brazilian basins. Water Policy 2018, 21, 206 -220.
AMA StyleRafael O. Tiezzi, Paulo S. F. Barbosa, João E. G. Lopes, Alberto L. Francato, Renato C. Zambon, Alexandre Silveira, Paulo H. B. J. Menezes, Jorge M. G. P. Isidoro. Trends of streamflow under climate change for 26 Brazilian basins. Water Policy. 2018; 21 (1):206-220.
Chicago/Turabian StyleRafael O. Tiezzi; Paulo S. F. Barbosa; João E. G. Lopes; Alberto L. Francato; Renato C. Zambon; Alexandre Silveira; Paulo H. B. J. Menezes; Jorge M. G. P. Isidoro. 2018. "Trends of streamflow under climate change for 26 Brazilian basins." Water Policy 21, no. 1: 206-220.
The accurate characterisation of flow from urban surfaces to sewer/stormwater systems is important for urban drainage design and flood modelling/risk identification. However, the geometrical complexity and large variety of drainage structures (linking elements) available makes model calibration and verification difficult. In this study an extensive comparison between experimentally measured and numerically modelled flow characteristics in the vicinity of ten different designs of manhole grate was performed under drainage flow in sub‐critical conditions. Using a 2D surface PIV (sPIV) system the work presents the first detailed characterisation of velocity fields around these linking elements. In addition, it provides the first detailed verification of the ability of a 2D numerical model to describe both velocity fields and drainage flows. The overall comparison shows a close relationship between numerical and the experimental results with some higher inflows in the experimental results as a consequence of a localised transition from weir to orifice condition near the void areas of the grates. It was also noted that velocity differences decreased further from the manhole, due mainly to the more directional flow. Overall the work demonstrates the potential for further use of 2D numerical models to describe flow conditions at linking elements, either directly within modelling simulations or indirectly via the characterisation of energy loss coefficients.
R. Martins; M. Rubinato; G. Kesserwani; J. Leandro; S. Djordjević; J. D. Shucksmith. On the Characteristics of Velocities Fields in the Vicinity of Manhole Inlet Grates During Flood Events. Water Resources Research 2018, 54, 6408 -6422.
AMA StyleR. Martins, M. Rubinato, G. Kesserwani, J. Leandro, S. Djordjević, J. D. Shucksmith. On the Characteristics of Velocities Fields in the Vicinity of Manhole Inlet Grates During Flood Events. Water Resources Research. 2018; 54 (9):6408-6422.
Chicago/Turabian StyleR. Martins; M. Rubinato; G. Kesserwani; J. Leandro; S. Djordjević; J. D. Shucksmith. 2018. "On the Characteristics of Velocities Fields in the Vicinity of Manhole Inlet Grates During Flood Events." Water Resources Research 54, no. 9: 6408-6422.
Accurately quantifying the capacity of sewer inlets (such as manhole lids and gullies) to transfer water is important for many hydraulic flood modelling tools. The large range of inlet types and grate designs used in practice makes the representation of flow through and around such inlets challenging. This study uses a physical scale model to quantify flow conditions through a circular inlet during shallow steady state surface flow conditions. Ten different inlet grate designs have been tested over a range of surface flow depths. The resulting datasets have been used (i) to quantify weir and orifice discharge coefficients for commonly used flood modelling surface–sewer linking equations and (ii) to validate a 2D finite difference model in terms of simulated water depths around the inlet. Calibrated weir and orifice coefficients were observed to be in the range 0.115–0.372 and 0.349–2.038, respectively, and a relationship with grate geometrical parameters was observed. The results show an agreement between experimentally observed and numerically modelled flow depths but with larger discrepancies at higher flow exchange rates. Despite some discrepancies, the results provide improved confidence regarding the reliability of the numerical method to model surface to sewer flow under steady state hydraulic conditions.
Matteo Rubinato; Seungsoo Lee; Ricardo Martins; James D. Shucksmith. Surface to sewer flow exchange through circular inlets during urban flood conditions. Journal of Hydroinformatics 2018, 20, 564 -576.
AMA StyleMatteo Rubinato, Seungsoo Lee, Ricardo Martins, James D. Shucksmith. Surface to sewer flow exchange through circular inlets during urban flood conditions. Journal of Hydroinformatics. 2018; 20 (3):564-576.
Chicago/Turabian StyleMatteo Rubinato; Seungsoo Lee; Ricardo Martins; James D. Shucksmith. 2018. "Surface to sewer flow exchange through circular inlets during urban flood conditions." Journal of Hydroinformatics 20, no. 3: 564-576.
RESUMO Um dos impactos da urbanização no meio ambiente é a alteração do processo de transformação da chuva em escoamento superficial, levando à alteração da qualidade dos recursos hídricos. Com este trabalho, objetivou-se simular o transporte de partículas em suspensão e de poluentes dissolvidos, transportados pelo escoamento, sobre uma superfície impermeável em escala de laboratório. O modelo experimental consistiu de um simulador para a aplicação de chuva artificial sobre uma superfície acrílica impermeável com 8,40 m2, na qual foram definidas quatro posições para a distribuição do cloreto de sódio e da areia fina, simulando fontes difusas de poluição. Os resultados indicaram diferenças entre os tempos de pico do transporte de poluentes dissolvidos e em suspensão, em função da posição desses. O efeito de first flush foi verificado para os poluentes dissolvidos independentemente da posição da fonte, enquanto para os poluentes transportados em suspensão o mesmo efeito só foi verificado quando a fonte estava mais próxima da saída da superfície impermeável.
Jéssica Giacchetto Felice; Alexandre Silveira; Jorge Manuel Pereira Guieiro Isidoro; Flávio Aparecido Gonçalves; Antônio Marciano da Silva. Simulação do transporte de partículas em suspensão e de poluentes dissolvidos pelo escoamento em superfícies impermeáveis: uma contribuição ao saneamento urbano. Engenharia Sanitaria e Ambiental 2018, 23, 405 -414.
AMA StyleJéssica Giacchetto Felice, Alexandre Silveira, Jorge Manuel Pereira Guieiro Isidoro, Flávio Aparecido Gonçalves, Antônio Marciano da Silva. Simulação do transporte de partículas em suspensão e de poluentes dissolvidos pelo escoamento em superfícies impermeáveis: uma contribuição ao saneamento urbano. Engenharia Sanitaria e Ambiental. 2018; 23 (2):405-414.
Chicago/Turabian StyleJéssica Giacchetto Felice; Alexandre Silveira; Jorge Manuel Pereira Guieiro Isidoro; Flávio Aparecido Gonçalves; Antônio Marciano da Silva. 2018. "Simulação do transporte de partículas em suspensão e de poluentes dissolvidos pelo escoamento em superfícies impermeáveis: uma contribuição ao saneamento urbano." Engenharia Sanitaria e Ambiental 23, no. 2: 405-414.
Hydraulic models of sewer systems are commonly used to predict the risk of urban flooding. However, suitable calibration datasets in flood conditions are scarce. The quantification of energy losses within manhole structures is a current source of uncertainty within such models. To address this gap, a scaled physical manhole model is used to quantify hydraulic energy losses during surcharging and non-surcharging conditions. Two different novel configurations were tested; (1) With and without the presence of a manhole lid; (2) With and without the presence of a shallow flow on the surface. Results showed that total head losses were found to increase in surcharging conditions. The presence of the lid also marginally increased total head losses. The datasets are used to assess the performance of a numerical urban flood model (SIPSON) and comparisons highlighted that SIPSON tends to overestimate energy losses in surcharging conditions.
M. Rubinato; R. Martins; J. D. Shucksmith. Quantification of energy losses at a surcharging manhole. Urban Water Journal 2018, 15, 234 -241.
AMA StyleM. Rubinato, R. Martins, J. D. Shucksmith. Quantification of energy losses at a surcharging manhole. Urban Water Journal. 2018; 15 (3):234-241.
Chicago/Turabian StyleM. Rubinato; R. Martins; J. D. Shucksmith. 2018. "Quantification of energy losses at a surcharging manhole." Urban Water Journal 15, no. 3: 234-241.
Catchment geomorphology is one of the most important factors governing runoff and erosion. However, its complexity is difficult to describe accurately; thus, for simplicity, many studies assume hillslopes with a uniform sloping profile. The influence of this simplification on estimating the rainfall-runoff and sediment loss processes is not well understood. In an effort to improve our understanding, this study relies on laboratory experiments using a movable rainfall simulator and a 6-m-long, 3-segment soil flume to simulate the effect of static and moving storms on differently shaped hillslopes: uniform, convex, concave, convex-concave, and concave-convex profiles. Therefore, variables, such as rainfall intensity, soil and water characteristics, and storm speed, were kept constant throughout the experiments. The work confirms empirically that storm movement and hillslope shape are central factors in the soil loss and overland flow processes. The results led to the following conclusions: (1) hillslope shape affected erosion for both nonmoving and moving rainstorms; (2) downslope moving storms led to higher runoff and sediment loss peaks than upslope moving storms; and (3) convex surfaces were the most hazardous in terms of the generation of runoff and erosion.
João L. M. P. De Lima; Jorge M. G. P. Isidoro; M. Isabel P. De Lima; Vijay P. Singh. Longitudinal Hillslope Shape Effects on Runoff and Sediment Loss: Laboratory Flume Experiments. Journal of Environmental Engineering 2018, 144, 04017097 .
AMA StyleJoão L. M. P. De Lima, Jorge M. G. P. Isidoro, M. Isabel P. De Lima, Vijay P. Singh. Longitudinal Hillslope Shape Effects on Runoff and Sediment Loss: Laboratory Flume Experiments. Journal of Environmental Engineering. 2018; 144 (2):04017097.
Chicago/Turabian StyleJoão L. M. P. De Lima; Jorge M. G. P. Isidoro; M. Isabel P. De Lima; Vijay P. Singh. 2018. "Longitudinal Hillslope Shape Effects on Runoff and Sediment Loss: Laboratory Flume Experiments." Journal of Environmental Engineering 144, no. 2: 04017097.