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1.
Sci Total Environ ; 842: 156751, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35724783

RESUMO

One of the most severe climate risks that is expected to affect all regions is related to stormwater. Climate models, constructed based on long-term trends, show that extreme weather events such as storms, cloudbursts and a large rise in sea level will be significant in the coming decades. Moreover, even the frequency and intensity of "normal" rainfall events, such as microbursts, are expected to be remarkably higher than today in some regions. The efficiency of urban drainage systems is affected by the land use in its whole catchment. In addition to the climate stress, there is ongoing continuous densification of urban space, resulting in more buildings and larger areas being covered with impervious surfaces. Planning decisions today approving such compaction do not consider the impacts beyond the close proximity of the land parcel. As a result, by following the current planning practices, cities are becoming extremely vulnerable to stormwater flooding (flash floods). This study presents a holistic and dynamic planning method - the Extreme Weather Layer (EWL) - that makes it possible to analyse the impact of a single development (e.g. paving a gravel parking lot with asphalt or turning an area of urban greenery into a shopping centre) on the performance of the urban drainage system and therefore on the flooding risk of the whole catchment. The EWL is based on a widely accepted drainage modelling engine coupled with GIS system and other databases which provide spatial information. Thus, the EWL combined with the systemic approach of turning from grey to green infrastructure could be a smart tool for implementing NBS solutions for stormwater management in climate adaptation in urban areas. This smart tool could indicate how much more green infrastructure is needed and which places in the city the mitigative NBS measures would help significantly.


Assuntos
Clima Extremo , Aclimatação , Cidades , Mudança Climática , Inundações , Chuva , Tempo (Meteorologia)
2.
Sensors (Basel) ; 21(11)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198799

RESUMO

Commercial unmanned aerial vehicles continue to gain popularity and their use for collecting image data and recording new phenomena is becoming more frequent. This study presents an effective method for measuring the concentration of fluorescent dyes (fluorescein and Rhodamine WT) for the purpose of providing a mathematical dispersion model. Image data obtained using a typical visible-light camera was used to measure the concentration of the dye floating on water. The reference measurement was taken using a laboratory fluorometer. The article presents the details of three extensive measurement sessions and presents elements of a newly developed method for measuring fluorescent tracer concentrations. The said method provides tracer concentration maps presented on the example of an orthophoto within a 2 × 2 m discrete grid.

3.
PeerJ ; 9: e10938, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33665035

RESUMO

BACKGROUND: This paper analyzes the impact of changes in fertilization on crop yields and the runoff of nutrients from a small agricultural catchment (176 km2) to a shallow bay, using the SWAT model. Puck Bay is part of the Gulf of Gdansk and belongs to the Baltic Sea. The whole area of Puck Bay (364 km2) is protected (Natura 2000) yet despite this it suffers from eutrophication problems due to the relatively minimal depth and difficult water exchange. METHODS: The paper presents a comparison of the calculated yields and the runoff of nutrients and pesticides in the SWAT model, for a small agricultural coastal catchment. Calculations were made for 13 crop scenarios with weather data from 2011 to 2019. For each crop, an agriculture calendar was made. Two variants of fertilization were considered (autofertilization mode and according to the calendar). The nutrient runoff was calculated depending on the adopted scenario. In addition, the fate of selected pesticides was simulated. RESULTS: Depending on the crop, the annual load of NO3into the stream ranged from 0.74 to 3.65 kg ha-1. The annual load of organic phosphorous into the stream was between 0.686 and 3.64 kg ha-1. This is lower than in the majority of EU or Baltic countries. The surface runoff of dissolved Glyphosate was equal to 286 mg ha-1. The annual loads of nutrients from the catchment area are equivalent in both fertilization modes. Regardless of the selected fertilization mode, in addition to the dosage, the form of nutrients is important for the model.

4.
Water Environ Res ; 81(11): 2353-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19957767

RESUMO

The aim of this study was to use computational fluid dynamics for predicting the behavior of reactive pollutants (ammonia and phosphate) in the aerobic zone of the bioreactor located at the Wschod wastewater treatment plant in Gdansk, Poland. The one-dimensional advection-dispersion equation was combined with simple biokinetic models incorporating the Monod-type expressions as source terms for the two pollutants. The problem was solved numerically by a multi-step splitting technique algorithm. The dispersion coefficient, E(L), was estimated using a statistical method and numerical optimization based on experimental data from three tracer studies. With the first method, the values of EL varied within the range 1082 to 1860 m2/h and 695 to 1355 m2/h, respectively, in sections 1 and 2 of the aerobic zone. Except for one case, deviations of the corresponding numerically optimized values of E(L) did not exceed 14%. The maximum specific rates of nitrification [r(n,max,20) = 4.6 g N/(kg VSS h)] and phosphate uptake [r(Pupt,max,20) = 13.5 g P/(kg VSS h)] at T = 20 degrees C were determined based on laboratory batch experiments. With minor adjustments of the kinetic parameters, the model was capable of accurately predicting the longitudinal profiles of ammonia and phosphate in the aerobic zone, and the simulation results were presented using the actual horizontal geometry of the bioreactor as a background.


Assuntos
Amônia/química , Modelos Teóricos , Fosfatos/química , Poluentes Químicos da Água/química , Reatores Biológicos , Simulação por Computador
5.
Water Environ Res ; 77(5): 525-32, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16274087

RESUMO

A model of temperature dynamics was developed as part of a general model of activated-sludge reactors. Transport of heat was described by the one-dimensional, advection-dispersion equation, with a source term based on a theoretical heat balance over the reactor. The model was compared to several reference models, including a tanks-in-series model and the dispersion model with heat components neglecting biochemical-energy inputs and other activated-sludge, heat-balance terms. All the models were tested under steady-state and dynamic conditions at a full-scale facility, the Rock Creek wastewater treatment plant in Hillsboro, Oregon, using meteorological data from a station located 16 km from the plant. The dispersion model and tanks-in-series model matched in situ temperature data with absolute-mean errors less than 0.1 degrees C. Neglecting biochemical-heat-energy inputs in the activated-sludge reactor underestimated temperatures by up to 0.5 degrees C. The biochemical-heat-energy inputs accounted for 30 to 40% of the total heat flux throughout the year.


Assuntos
Reatores Biológicos , Esgotos/química , Temperatura , Meio Ambiente , Modelos Teóricos , Fatores de Tempo
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