scholarly journals Predição do escoamento superficial e consequentes alagamentos em centros urbanos

2020 ◽  
Vol 11 (5) ◽  
pp. 1-11
Author(s):  
Marco Aurélio Calixto Ribeiro de Holanda ◽  
Willames De Albuquerque Soares ◽  
Diogo Botelho Correa de Oliveira
Keyword(s):  

Os alagamentos são um problema em vários centros urbanos decorrentes da descaracterização natural do solo e do aumentando do escoamento superficial. A caracterização hidrodinâmica dos solos pode ser realizada por ensaios de campo ou laboratoriais visando a predição destes alagamentos. Sendo assim, objetivou-se estimar o escoamento superficial de água no solo por meio de simulações utilizando o Hydrus-1D, para explicar os alagamentos que ocorrem numa área urbana. Para obtenção dos parâmetros hidrodinâmicos seguiu-se a metodologia do Beerkan of Estimation Soil Transfer (BEST) realizada em laboratório com colunas de acrílico e dois solos distintos, enquanto que as simulações do escoamento superficial foram feitas com Hydrus-1D. Por meio das curvas de infiltração verificou-se que o solo menos arenoso possui uma capacidade de infiltração menor. A primeira simulação mostrou que o escoamento superficial cumulativo foi de 355,67 mm dia-1 enquanto que na segunda simulação o escoamento superficial acumulado foi de 362,03 mm dia-1. A realização dos ensaios de infiltração apenas na superfície do perfil do solo podem acarretar em resultados imprecisos, uma vez que a discrepância entre os valores simulados do escoamento superficial chegam a 105,14%. Deste modo, para uma estimativa de escoamento superficial mais precisa são necessários sucessivos ensaios de infiltração em diferentes profundidades.

2012 ◽  
Vol 16 (8) ◽  
pp. 2485-2497 ◽  
Author(s):  
B. Leterme ◽  
D. Mallants ◽  
D. Jacques

Abstract. The sensitivity of groundwater recharge to different climate conditions was simulated using the approach of climatic analogue stations, i.e. stations presently experiencing climatic conditions corresponding to a possible future climate state. The study was conducted in the context of a safety assessment of a future near-surface disposal facility for low and intermediate level short-lived radioactive waste in Belgium; this includes estimation of groundwater recharge for the next millennia. Groundwater recharge was simulated using the Richards based soil water balance model HYDRUS-1D and meteorological time series from analogue stations. This study used four analogue stations for a warmer subtropical climate with changes of average annual precipitation and potential evapotranspiration from −42% to +5% and from +8% to +82%, respectively, compared to the present-day climate. Resulting water balance calculations yielded a change in groundwater recharge ranging from a decrease of 72% to an increase of 3% for the four different analogue stations. The Gijon analogue station (Northern Spain), considered as the most representative for the near future climate state in the study area, shows an increase of 3% of groundwater recharge for a 5% increase of annual precipitation. Calculations for a colder (tundra) climate showed a change in groundwater recharge ranging from a decrease of 97% to an increase of 32% for four different analogue stations, with an annual precipitation change from −69% to −14% compared to the present-day climate.


2021 ◽  
Author(s):  
Alice Künzel
Keyword(s):  

<p>Winterweizen ist die wichtigste Kulturpflanze in Deutschland, weshalb in der vorliegenden Arbeit eine statistisch-klimatologische Analyse der Evapotranspiration von Winterweizen mittels Lysimeterdaten und Modellergebnissen in Groß Lüsewitz, Brandis und Potsdam erfolgte. Die ausgewählten Standorte unterscheiden sich hinsichtlich der klimatischen und edaphischen Verhältnisse. In Groß Lüsewitz und in Brandis wird die aktuelle Evapotranspiration (AET) mittels Lysimetern gemessen. Diese Messdaten wurden mit der modellierten AET der Bodenwasserhaushaltsmodelle METVER und HYDRUS-1D verglichen, wobei nur Anbaujahre des Winterweizens am jeweiligen Lysimeterstandort berücksichtigt wurden. Für Potsdam erfolgte für vier Klimaperioden nur eine modellbasierte Auswertung der AET. Die Analyse beschränkt sich an allen Standorten auf die Vegetationsperiode des Winterweizens, welche die Monate März bis August umfasst.</p> <p>Die für das Wachstum des Winterweizens entscheidenden Monate sind April bis Juni. In dieser Hauptwachstumszeit ist der Wasserverbrauch des Winterweizens am größten, weshalb eine kontinuierliche Wasserversorgung gewährleistet sein muss. Die Analyse ergab, dass die Variabilität der gemessenen AET mittels beider Bodenwasserhaushaltsmodelle an den Lysimeterstandorten, wenn auch unterschiedlich gut im Vergleich zur gemessenen AET auf den Lysimetern, simuliert werden konnte.</p> <p>Die potentielle Evapotranspiration (ETP) wird in METVER mit einem modifizierten Berechnungsansatz nach Turc-Wendling und in HYDRUS-1D nach dem Ansatz von Penman-Monteith modelliert. In Groß Lüsewitz und in Potsdam wurden trotz der unterschiedlichen Berechnungsansätze ähnliche Ergebnisse erzielt. Für Brandis dagegen ergaben sich deutlich unterschiedliche Ergebnisse.</p> <p>Wenn sehr trockene Bedingungen in einzelnen Monaten der jeweiligen Anbaujahre vorlagen, war die Differenz zwischen der modellierten ETP des jeweiligen Bodenwasserhaushaltsmodells und der gemessenen AET auf den Lysimetern deutlich ausgeprägt. Anhand des verwendeten Ariditätsindexes konnte festgestellt werden, dass in Groß Lüsewitz die Vegetationsperiode des Winterweizens bei METVER in vier und bei HYDRUS in einem von insgesamt 26 Anbaujahren durchweg sehr trocken war. In Brandis waren es bei METVER drei und bei HYDRUS zwei von insgesamt 12 Anbaujahren.</p> <p>Mittels einer modellbasierten Trendanalyse der ETP und der AET am jeweiligen Standort konnte für Groß Lüsewitz im Zeitraum 1975-2020, für Brandis (1981-2020) und für Potsdam (1901-2020) eine zunehmende Trockenheit festgestellt werden, sodass die Bewässerung von Winterweizen hier zukünftig an Bedeutung gewinnen wird.</p>


2018 ◽  
Vol 66 (2) ◽  
pp. 232-245 ◽  
Author(s):  
Vakhtang Shelia ◽  
Jirka Šimůnek ◽  
Ken Boote ◽  
Gerrit Hoogenbooom

AbstractAccurate estimation of the soil water balance of the soil-plant-atmosphere system is key to determining the availability of water resources and their optimal management. Evapotranspiration and leaching are the main sinks of water from the system affecting soil water status and hence crop yield. The accuracy of soil water content and evapotranspiration simulations affects crop yield simulations as well. DSSAT is a suite of field-scale, process-based crop models to simulate crop growth and development. A “tipping bucket” water balance approach is currently used in DSSAT for soil hydrologic and water redistribution processes. By comparison, HYDRUS-1D is a hydrological model to simulate water flow in soils using numerical solutions of the Richards equation, but its approach to crop-related process modeling is rather limited. Both DSSAT and HYDRUS-1D have been widely used and tested in their separate areas of use. The objectives of our study were: (1) to couple HYDRUS-1D with DSSAT to simulate soil water dynamics, crop growth and yield, (2) to evaluate the coupled model using field experimental datasets distributed with DSSAT for different environments, and (3) to compare HYDRUS-1D simulations with those of the tipping bucket approach using the same datasets. Modularity in the software design of both DSSAT and HYDRUS-1D made it easy to couple the two models. The pairing provided the DSSAT interface an ability to use both the tipping bucket and HYDRUS-1D simulation approaches. The two approaches were evaluated in terms of their ability to estimate the soil water balance, especially soil water contents and evapotranspiration rates. Values of thedindex for volumetric water contents were 0.9 and 0.8 for the original and coupled models, respectively. Comparisons of simulations for the pod mass for four soybean and four peanut treatments showed relatively highdindex values for both models (0.94–0.99).


2013 ◽  
Vol 13 (1) ◽  
pp. 161-174 ◽  
Author(s):  
Pedro Tyaquiçã da Silva Santos ◽  
Sylvana Melo dos Santos ◽  
Suzana Maria Gico Lima Montenegro ◽  
Artur Paiva Coutinho ◽  
Glawbber Spíndola Saraiva de Moura ◽  
...  
Keyword(s):  

Na atualidade, metade da população mundial reside em centros urbanos, e os impactos negativos decorrentes de eventos hidrológicos têm sido recorrentes, visto que, com o aumento da impermeabilização, há redução nas taxas de infiltração, levando à diminuição da recarga dos aquíferos e à diminuição do escoamento de base. Consequentemente, o escoamento superficial é intensificado, aumentando a frequência e a magnitude dos picos de cheia, o que pode resultar na ocorrência de inundações, especialmente nos centros urbanos. Por outro lado, verifica-se já há algum tempo o emprego de telhados verdes em várias partes do mundo para contribuição arquitetônica estética e melhoria do conforto ambiental. Além desses enfoques, esta solução vem sendo tratada, também, como uma estrutura de controle do escoamento pluvial. Considerando características reais e os dados obtidos em campo, foi realizada a simulação da dinâmica da água em dois telhados verdes, com o emprego do código computacional Hydrus-1D, para diferentes intensidades de precipitação, visando verificar o desempenho desse sistema construtivo na redução do escoamento superficial. Os hidrogramas de saída mostraram-se qualitativamente adequados e quantitativamente coerentes e pode-se concluir que os telhados verdes constituem importantes dispositivos no amortecimento do escoamento superficial oriundo dos telhados, para as condições climáticas da área investigada.


Author(s):  
Jianmin Bian ◽  
Qian Wang ◽  
Siyu Nie ◽  
Hanli Wan ◽  
Juanjuan Wu

Abstract Fluctuations in groundwater depth play an important role and are often overlooked when considering the transport of nitrogen in the unsaturated zone. To evaluate directly the variation of nitrogen transport due to fluctuations in groundwater depth, the prediction model of groundwater depth and nitrogen transport were combined and applied by least squares support vector machine and Hydrus-1D in the western irrigation area of Jilin in China. The calibration and testing results showed the prediction models were reliable. Considering different groundwater depth, the concentration of nitrogen was affected significantly with a groundwater depth of 3.42–1.71 m, while it was not affected with groundwater depth of 5.48–6.47 m. The total leaching loss of nitrogen gradually increased with the continuous decrease of groundwater depth. Furthermore, the limited groundwater depth of 1.7 m was found to reduce the risk of nitrogen pollution. This paper systematically analyzes the relationship between groundwater depth and nitrogen transport to form appropriate agriculture strategies.


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