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[en] The following study treats a sector of environmental policy which must take the aspects of stabilization, maintenance and development into account. The various points of view which are associated with precautionary environmental planning are covered in detail. Whilst considering the methodological and material possibilities, appropriate attention is paid to the question of climatological air hygiene for town and regional planning. The area in question extends to the surrounding regions of the given town. (orig.)
[de]Das vorliegende Werk behandelt einen Sektor der Umweltpolitik, der Aspekte der Sanierung, Erhaltung und Gestaltung zu beruecksichtigen hat. Auf die vielfaeltigen Gesichtspunkte, die mit einer Umweltplanung im Dienst des Vorsorgeprinzips verbunden sind, wird daher ausfuehrlich eingegangen. Unter Beruecksichtigung der gegebenen methodischen und materiellen Moeglichkeiten wird eine sachgerechte Behandlung der klimatologischen lufthygienischen Fragestellungen im Rahmen der Stadt- und Regionalplanung aufgezeigt. Der raeumliche Bezug wird dabei bewusst von der Stadt auf die sie umgebende Region ausgedehnt. (orig.)
[en] The author describes the importance from the discovery of two North American scientists when finding evidences of a possible invasion of life in the terrestrial surface a lot earlier of known until now is accepted, when found indications of organisms like bacteria or algae in rocks between 800 and 1200 million years
[en] Water quality impairments due to pollutants from agricultural, rural, and urban lands continue to present environmental and health related challenges, attributable to a combination of climatic and anthropogenic factors. Changes in climate can potentially affect the movement of water and pollutants in our environment. This is particularly so in areas with subsurface drainage systems which, by design, provide rapid removal of water from landscapes but, inadvertently, provide accelerated conduits for associated pollutants. Subsurface drainage is particularly important in the U.S. Midwest region as it provides a viable means of growing crops in an otherwise waterlogged environment. In the Western Lake Erie Basin (WLEB), part of the aforementioned region, 70% of the land area is agricultural. It is generally unclear how much of the land area is in subsurface drainage (OLEPTF 2013) but best guess estimates can be derived based on the proportion of cultivated area with soils classified as poorly drained or very poorly drained (Sui and Frankenberger 2008). This basin has experienced increases in spring precipitation over the past 50 years (Sekaluvu et al. 2018) and one-day maximum precipitation is expected to increase going into the future, particularly during the spring and summer (Mehan 2018). The aim of this study was to assess the impact of changing precipitation patterns on hydrology and nutrient losses in subsurface-drained systems in the WLEB. The study site for this work was the Matson Ditch Watershed, a 46 km2 (18 mi2 ) agriculturedominated subsurface-drained watershed that is a constituent of the WLEB. Consistent with the larger Basin, agricultural land comprises about 68 % of the watershed and is dominated by corn, soybeans, and winter wheat. This study was conducted using a modelling approach with the Soil and Water Assessment Tool (Arnold et al. 1998). Methodologies and approaches are applicable beyond the study region.
[en] SolWat is a new hybrid photochemical and photovoltaic (PV) technology for simultaneous solar water disinfection (SODIS) and electricity production (Vivar at al. 2010). It was developed based exclusively on using solar energy for two final applications: (1) visible and near-infrared light to generate renewable electricity; (2) far-infrared and UV (UVA-UVB) light for bacteria inactivation. SolWat comprises a PV module and a water disinfection reactor that is fully integrated into a single unit. The PV module acts as the base of the water disinfection reactor with a water layer on top that is transparent to visible and near-infrared light. Water disinfection occurs between the water disinfection reactor´s glass cover and the PV module. The feasibility of this concept has been demonstrated in previous works (Pichel et al. 2016, 2017), which show that the hybrid system (PV + SODIS) achieves the same electrical and disinfection results as two independent systems (PV module and a disinfection reactor separately) during 6 h of experimentation. Pichel et al. (2018) have also demonstrated that under strong climate conditions, E. coli, total coliforms, Enterococcus spp. and Clostridium perfringens were completed inactivated after 3 hours of solar treatment, reducing the treatment time recommended for conventional SODIS reactors (6 h) by half. The cited works show that the PV module integrated into SolWat does not lead to major losses caused by the reduced solar irradiation received (lower current, I) as such losses are compensated by the cooling effect of the water layer being purified on top of the module (higher voltage, V). Accordingly, the refrigerated effect of water being purified on the PV module at the start of the treatment process is maximum. Thus the SolWat energy output could benefit from lower temperatures in short treatment times if properly optimised in combination with a smart water disinfection process strategy on top. This work aims to study the effect of the water disinfection reactor on the electrical performance of the photovoltaic module integrated into the SolWat system on different hydraulic retention times (HRT).
[en] CALMET/CALPUFF modeling system is frequently used in the study of atmospheric processes and pollution, and several validation tests were performed until now; nevertheless, most of them were based on experiments with a large compilation of surface and aloft meteorological measurements, rarely available. At the same time, the use of a large operational smokestack as tracer/pollutant source is not usual. In this work, first CALMET meteorological diagnostic model is nested to WRF meteorological prognostic model simulations (3x3 km2 horizontal resolution) over a complex terrain and coastal domain at NW Spain, covering 100x100 km2 , with a coal-fired power plant emitting SO2. Simulations were performed during three different periods when SO2 hourly glc peaks were observed. NCEP reanalysis were applied as initial and boundary conditions. Yong Sei University-Pleim-Chang (YSU) PBL scheme was selected in the WRF model to provide the best input to three different CALMET horizontal resolutions, 1x1 km2 , 0.5x0.5 km2 , and 0.2x0.2 km2. The best results, very similar between them, were achieved using the last two resolutions; therefore, the 0.5x0.5 km2 resolution was selected to test different CALMET meteorological inputs, using several combinations of WRF outputs and/or surface and upper-air measurements available in the simulation domain. With respect to meteorological aloft models output, CALMET PBL depth estimations are very similar to PBL depth estimations using upper-air measurements (rawinsondes), and significantly better than WRF PBL depth results. Regarding surface models surface output, the available meteorological sites were divided in two groups, one to provide meteorological input to CALMET (when applied), and another to models validation. Comparing WRF and CALMET outputs against surface measurements (from sites for models validation) the lowest RMSE was achieved using as CALMET input dataset WRF output combined with surface measurements (from sites for CALMET model input). Following, CALPUFF model was applied to simulate the local atmospheric diffusion of SO2 (as an inert tracer) from a large power plant smokestack (with four parallel independent liners), considering two different stack configurations (one single point source as a summa of four liners vs. one point source per liner) and two different CALMET meteorological simulations (using as input dataset only the WRF model output vs. only surface and upper-air meteorological measurements). Comparison of those CALPUFF simulations results against the hourly average ground level concentration (glc) measurements shows that the best model performance was obtained by using only WRF model output as CALMET input; also, better glc results are obtained considering one point source per liner in CALPUFF simulations. (Author)
[en] Results of a conference on the title subject are reported. Recommendations are given based on which policy makers can handle uncertainties in decision making processes. One of the cases in this report concerns energy supply security. Another case is about air quality
[nl]Onzekerheid wordt voor het overheidsbeleid een steeds belangrijkere factor, zowel door de groeiende complexiteit van de beleidsomgeving als door hoge economische, maatschappelijke en politieke kosten van beleidsfouten. Tegelijkertijd blijkt het voor beleidsmakers moeilijk te zijn om in het beleid goed rekening te houden met relevante onzekerheden. Op de conferentie wisselden onderzoekers en beleidsmakers vanuit verschillende beleidsterreinen hun ervaringen uit. Aan het slot van de publicatie wordt een tiental aanbevelingen gedaan voor een betere omgang met onzekerheid. Een van de besporken voorbeelden betreft de energievoorzieningszekerheid, terwijl een andere casus over luchtkwaliteit gaat
[en] There is a keen awareness of the effects of water quality on human health and behaviour in developing countries arising from well documented cases which can be found in the literature. Also in Nigeria there are various concerns about incidents of toxic waste disposal, groundwater pollution through oil spillages, waste disposal practices by agricultural, domestic and industrial activities which affect the domestic water supplies and the environment. The aims of this paper are to highlight the role of water quality in human health; provide a framework for water related health assessment, present results of case studies and recommend appropriate strategies to safeguard human health from contaminated water sources. Major health problems, other than those due to micro-biological contamination of water sources, such as cholera and typhoid, have not been reported or linked to water supplies in Nigeria. Yet there are symptoms of and growing incidences of various diseases, such as psychopathic and neurological disorders which have been linked to contaminated water supplies in developed countries. The major, minor and trace concentrations of elements in water supplies in Nigeria are usually determined in the ppm range whereas most trace elements are hazardous to human health in the ppb or μg/l levels. The reason for this state of affairs is that the instrumentation required for determination of elemental concentrations at the ppb level is not readily available to researchers. Most reports on water quality do not provide any links to the major health problems which have been demonstrated elsewhere as responsible for major pathologic and neurologic disorders, including outright fatalities. Recent studies in Europe and Japan link several diseases, including kidney failure, mood disturbance and other neurologic disorders, heart, liver and kidney damage including death from eating poisonous fish caught in polluted waters, to contamination of water supplies by heavy metals in trace concentrations. Most of the ailments, including mood disturbances and psychological disorders, are reportedly on the increase in most urban and industrialized areas of Nigeria. Perhaps a study should be conducted among the population in order to relate the pattern of water pollution related diseases to health factors in Nigeria
[en] The selection of water quality variables to be sampled is a highly complicated issue with significant cost implications since there are several variables to choose from. Essentially, there are five significant issues that need to be stressed regarding variables to be monitored: (a) variable selection should be based on objectives of monitoring; that is, the type and nature of information required for water quality assessment must be identified first; (b) the selection of variables should be realized by a systematic approach as a monitoring network itself is a family of systematically operated monitoring stations; (c) variable to be monitored, i.e., constituents and pollutants, should be selected so as to identify the biochemical composition of the aquatic ecosystem (constituents), including those that characterize the natural driving forces and the anthropogenic impact (pollutants) representing the modifying forces; (d) a number of investigations has to be carried out before making the selection among a large number of variables (e.g. water quality criteria, pollution inventories and impacts, water use, etc.); (e) economics of monitoring play a significant role in selection of variables to be sampled. Practically, there are no standard methods that may be used in either the selection of variables or the assessment of an already selected list of variables monitored. To this end, the current paper proposes an approach that may facilitate the selection or assessment procedure. The study presents the above
[en] Determining the accurate rate of pollution decay coefficient is an important issue in water quality management due to its effects on oxygen consumption in rivers. The main purpose of this paper is to determine the decay rate coefficient (Kc) of Talar River, Iran, by means of field experiments and to specialize empirical equations in spring and summer. Former studies on this topic have been published by Yeli Zink et al. (2016) for simulation of parameters in three stations including COD, NH4-N and TP and hydraulic characteristics by QUAL2K model; the results of two methods to obtain the decay rate coefficient have been compared. Later, Feria Diaz et al. (2017) estimated the decay rate coefficient and the re-aeration coefficient of Sinu River in northwestern Colombia. The main parameters included BOD, DO, temperature and hydraulic characteristics; the values of Kc are between 0.1 and 0.37 according to Streeter and Phelps equation. Recently, Abdollahi et al. (2018) evaluated the best equations of the re-aeration rate coefficient, among 29 most used equations based on the dissolved oxygen modelling for Karoon River, Iran, at different seasons (2010-2011). Using Qual2Kw5.1 software, the relevant modelled re-aeration rate coefficients for each season were equal to 0.62, 0.23, 0.33 and 1.59 (d-1 ), respectively. Moghimi-Nezad et al. (2018) studied the seasonal variation of self-purification capacity of Karoon River, Iran. Results indicated that the decrease of nitrate in January and February and the decrease of BOD for all months except October up to 30% had the most positive effects on river water quality. The 30% decrease of wastewater flow rate containing pathogens had the most positive effects on the river water quality.