This paper presents the results of testing the applicability of the MIKE Basin model for simulating the efficiency of scenarios for reducing water pollution. The model has been tested on the Olšava River Basin (520 km2 ) which is a typical rural region with a heterogeneous mix of pollution sources with variable topography and land use. The study proved that the model can be calibrated successfully using even the limited amount of data typically available in rural basins. The scenarios of pollution reduction were based on implementation and intensification of municipal wastewater treatment and conversion of arable land on fields under the risk of soil erosion to permanent grassland. The application of simulation results of these scenarios with proposed measures proved decreasing concentrations in downstream monitoring stations. Due to the practical applicability of proposed measures, these could lead to fulfilment of the water pollution limits required by the Czech and EU legislation. However, there are factors of uncertainty that are discussed that may delay or limit the effect of adopted measures in small rural basins.
With regard to the water quality changes, the area of the Czech part of the Elbe River basin is extraordinarily dynamic. In the 20th century it experienced an enormous increase of load of pollution. Since the beginning of the 1990´s due to the political and economical changes we have witnessed a particularly intensive decrease in the emission volume and a related increase in water quality of watercourses. However, positive changes in the pollution load balance have occurred mainly in the biggest watercourses and these changes have not been accompanied by similar development in the whole river system. Using a newly created classification methodology the basic models of dynamics of water quality changes in the Elbe River basin have been derived. Based on GIS geostatistical analysis, regions with analogous water quality development trends have been defined for selected parameters and critical areas have been identified. It has become apparent that the prevailing part of the Elbe River basin has been experiencing a gradual increase in pollution. In addition, after a previous decrease, a number of watercourses experienced a recurrence of the increase in load. These areas are priorities for further development and the control of surface water protection against pollution. and Oblast české části povodí Labe je z hlediska změn kvality vody mimořádně dynamická. Díky intenzivnímu vývoji antropogenních aktivit a společenským změnám zaznamenala v průběhu 20. století nejprve enormní nárůst zátěže znečištěním, od počátku 90. let jsme naopak svědky mimořádně intenzivního snížení objemu emisí a souvisejícího zvyšování jakosti vody v tocích. Pozitivní změny v látkové bilanci jsou však soustředěny především na největší toky – Labe a Vltavu a nejsou doprovázeny obdobným vývojem v celém povodí. Pomocí nově vytvořené metodiky klasifikace vývoje kvality vody prezentované v článku byly na základě geostatistické analýzy sestaveny základní modely časové dynamiky změn kvality vody v povodí Labe. Pro jednotlivé ukazatele byly na základě analýzy v prostředí GIS vymezeny regiony s analogickými trendy vývoje kvality povrchových vod a identifikovány kritické oblasti. Ukazuje se, že přes pozitivní vývoj jakosti vody v hlavních sídelních a průmyslových regionech v 90. letech převažující část povodí Labe stále zaznamenává v jednotlivých ukazatelích postupný nárůst znečištění, na řadě toků navíc po předchozím poklesu dochází k opětovnému nárůstu zátěže. Tyto oblasti představují prioritu pro další rozvoj a řízení ochrany povrchových vod před znečištěním.
Although the quantification of real evapotranspiration (ETr) is a prerequisite for an appropriate estimation of the water balance, precision and uncertainty of such a quantification are often unknown. In our study, we tested a combined growth and soil water balance model for analysing the temporal dynamics of ETr. Simulated ETr, soil water storage and drainage rates were compared with those measured by 8 grass-covered weighable lysimeters for a 3-year period (January 1, 1996 to December 31, 1998). For the simulations, a soil water balance model based on the Darcy-equation and a physiological-based growth model for grass cover for the calculation of root water uptake were used. Four lysimeters represented undisturbed sandy soil monoliths and the other four were undisturbed silty-clay soil monoliths. The simulated ETr-rates underestimated the higher ETr-rates observed in the summer periods. For some periods in early and late summer, the results were indicative for oasis effects with lysimeter-measured ETr-rates higher than corresponding calculated rates of potential grass reference evapotranspiration. Despite discrepancies between simulated and observed lysimeter drainage, the simulation quality for ETr and soil water storage was sufficient in terms of the Nash-Sutcliffe index, the modelling efficiency index, and the root mean squared error. The use of a physiological-based growth model improved the ETr estimations significantly.
The paper presents the results of the study of the sediments deposition process in a settling basin by using a k-ε turbulence model. The results obtained are than compared with the results obtained by using 1 and 2 D mathematical models and field measurements. In the first step, the settling basin is designed based on the formulae recommended by classical approach. The transition zone at the entrance of settling basin is then adjusted to satisfy more uniform flow at the beginning of the active zone. The flow velocity variation and bed shear stress distribution over the cross section area are furthermore analyzed and questions suggesting further development of mathematical models are identified. For the second step, a schematized settling basin is then modelled in three-dimensional laterally confined model for the purpose of dealing with turbulences that potentially bring more sediment to the side and to the end of settling basin. Finally, recommendations for the design of settling basin are given by analyzing the results obtained by both mathematical and empirical methods. By comparison of the results obtained and field measurements made in Indonesia, useful design recommendations are derived. and Príspevok obsahuje výsledky štúdia sedimentačného procesu v usadzovacej nádrži s využitím modelu turbulencie k-ε. Takto získané výsledky sú porovnané s tými, ktoré boli získané pomocou jedno- a dvojdimenzionálneho modelu a s terénnymi meraniami. Najskôr bol sedimentačný bazén navrhnutý pomocou klasických vzorcov. Prechodová zóna a vstup do usadzovacieho bazénu bol potom upravený tak, aby zabezpečil relatívne homogénne prúdenie na začiatku aktívnej zóny. Boli analyzované zmeny rýchlosti prúdenia a rozdelenie trecích napätí na dne v priečnych rezoch koryta a boli identifikované problémy, ktoré by umožnili ďalší vývoj matematických modelov tohto javu. V ďalšom kroku bol modelovaný schematizovaný usadzovací bazén ako trojrozmerný, na oboch stranách ohraničený model, aby sa dalo manipulovať s turbulenciou, ktorá by mohla potenciálne dopraviť viac sedimentov na strany a na koniec sedimentačnej nádrže. Nakoniec uvádzame odporúčania pre návrh sedimentačných nádrží, vychádzajúc z výsledkov využitia matematických aj emprických metód. Porovnaním týchto výsledkov s výsledkami terénnych meraní v Indonézii boli navrhnuté užitočné odporúčania.
Bolbelasmus (Bolbelasmus) unicornis (Schrank, 1789) (Coleoptera: Geotrupidae) is a rare and threatened beetle distributed mostly in Central, Eastern and Southeast Europe. As a species of special conservation significance it is included in Annexes II and IV of the Habitat Directive of the European Union. Several new records of this species documented using light traps and soil sampling were recently reported in Serbia (the central part of the Balkan Peninsula). In this paper we present and discuss the current distribution of this species in the region studied based on GIS occurrence data. The distribution is mapped and values of environmental variables within this beetle's range are quantified using GIS technology. In addition, we predict its potential range in Serbia using a model based on the current distribution of this beetle, environmental variables and distribution of its food source.
In Tunisia especially in the Medjerda watershed the recurring of floods becoming more remarkable. In order to limit this risk, several studies were performed to examine the Medjerda hydrodynamic. The analysis of results showed that the recurrences of floods at the Medjerda watershed is strongly related to the sediment transport phenomena. Initially, a one dimensional modelling was conducted in order to determine the sediment transport rate, and to visualize the river morphological changes during major floods. In continuity of this work, we will consider a two-dimensional model for predicting the amounts of materials transported by the Medjerda River. The goal is to visualize the Medjerda behaviour during extreme events and morphological changes occurred following the passage of the spectacular flood of January 2003. As a conclusion for this study, a comparative analysis was performed between 1D and 2D models results. The objective of these comparisons is to visualize the benefits and limitations of tested models. The analysis of the results demonstrate that 2D model is able to calculate the flow variation, sediment transport rates, and river morphological changes during extreme events for complicated natural domains with high accuracy comparing with 1D Model.
This paper presents a semi-global mathematical model for an analysis of a signal of amperometric biosensors. Artificial neural networks were applied to an analysis of the biosensor response to multi-component mixtures. A large amount of the learning and test data was synthesized using computer simulation of the biosensor response. The biosensor signal was analyzed with respect to the concentration of each component of the mixture. The paradigm of locally weighted linear regression was used for retraining the neural networks. The application of locally weighted regression significantly improved the quality of the prediction of the concentrations.
Dispersal of the sevenspotted lady beetle, Coccinella septempunctata, was measured in a series of mark-release-recapture experiments in Utah alfalfa. In three experiments, samples were taken in a radial pattern around the release point. Released beetles for the most part left the 0.36 ha (68 m diameter) sample area within 24 hours, and their average residence time in the sample area was calculated as 12, 6 and 1.6 h in the three experiments, respectively. The spatial distribution of beetles around the point of release could be described with normal distributions whose variance increased linearly in time with 3.8, 1.1 and 0.34 m2 per hour. In three additional field experiments the departure of marked beetles was compared between sugar-sprayed plots and control plots. Residence time was 20-30% longer in sugar-sprayed plots than in control plots, with mean residences of 5.3, 3.6, and 2.9 h in the sugar-sprayed plots in the three experiments, respectively, and means of 4.4, 2.7, and 2.4 h in the control plots. The density of unmarked beetles rose by a factor of 10-20 in the sugar sprayed plots during the first 4 to 6 hours following early morning spraying of sugar. This rapid and substantial increase in density cannot be explained by the slightly longer residence time in sugar-sprayed plots. We hypothesize that the aggregation in sugar-sprayed plots is mostly due to greatly increased immigration into those plots, in response to volatiles produced by the plant-pest-predator assembly.
A model experimental investigation of the accuracy of ground station coordinates, determined by Doppler satellite observations is made, depending on the number of passes, satellite altitude, orbit inclination, frequency of Doppler transmitter, intervals of Doppler counts, etc. Using satellite pases at altitudes of 1000, 3000 a 5000 km, optimization of the Doppler observations is also achieved.
A fully preserved 14th-century AD bloomery furnace was excavated in 2014 on the settlement of Kolesovka-4 (Russia, Tula district). This extraordinary find has been taken as a model for experimental work. The iron ore used came from the Loknya River, a metallurgical conglomerate used came from the archaeological site of Staraya Ryazan. The most successful result was achieved by using the conglomerate from Staraya Ryazan – three pieces of blooms were made, weighing about 1 kg, and consisting of soft iron and a large number of very coarse slag inclusions. These show a similar trace-element composition as the medieval bloom coming from the same site. Experiments conducted have shown that the bloomery furnace uncovered at the Kolesovka-4 settlement is a rational pyrotechnological construction, allowing for a large number of smelting cycles. and V roce 2014 byla na sídlišti Kolesovka-4 (Rusko, okres Tula) odkryta plně zachovaná železářská pec ze 14. stol. n. l. Tento mimořádný nález posloužil jako model pro experimentální práce. Použitá železná ruda pochází z řeky Loknja, použitý metalurgický konglomerát pak z archeologické lokality Stará Rjazaň. Nejlepšího výsledku bylo dosaženo použitím konglomerátu ze Staré Rjazani – získány byly tři kusy železné houby vážící asi 1 kg a sestávající z měkkého železa a velkého množství velmi hrubých struskových vměstků. Ty vykazují podobné složení stopových prvků jako železná houba pocházející z té samé lokality. Provedené pokusy ukázaly, že redukční pec odkrytá na sídlišti Kolesovka-4 je racionální pyrotechnologické zařízení umožňující řadu výrobních cyklů.