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Conditions of physico-chemical and microbiological characteristics of agricultural soil of groundwater source of city Smederevska Palanka - Trnovce [Serbia]
2006
Pivic, R. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Rasulic, N. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Nikolovski, M. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Popovic, V. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu
In the frame of the project Water Supplying of the Cities and Protection of the Groundwater Quality in the Velika Morava Valley, was obtained the analysis of potential polluters of groundwater source of city Smederevska Palanka - Trnovce. This paper presents results of water physical, chemical and microbiological characteristics of soil. According to the results of research and way of usage of the soil, it was concluded that agricultural production does not have negative influence on quality of the groundwater source.
Afficher plus [+] Moins [-]Quality of the spring waters with regard to the level of lead, cadmium and zinc on territory of the Northern Kosovo and Metohija [Serbia]
2006
Babincev, Lj.M. (Fakultet tehnickih nauka, Kosovska Mitrovica (Serbia))
This is the presentation of the content of heavy metals (Pb, Cd and Zn) originating from the several representative locations of the natural water springs in the Northern Kosovo and Metohija . For the determination of presence and content of Pb, Cd and Zn in these spring waters the Potentiometric stripping analysis (PSA) method was used as a high-sensitive and selective electroanalytical technique.
Afficher plus [+] Moins [-]Nutrients and chlorophyll a dynamics in the inner part of Boka Kotorska Bay [Montenegro]
2006
Krivokapic, S. (Prirodno-matematicki fakultet, Podgorica (Montenegro). Studijska grupa za biologiju), E-mail: sladjana69@yahoo.com | Vuksanovic, N. (Institut za biologiju mora, Kotor (Montenegro)) | Stankovic, Z. (Prirodno-matematicki fakultet, Kragujevac (Serbia). Institut za biologiju i ekologiju)
Investigation of the nutrients and chlorophyll a concentrations, as indicators of trophic level, in the period from September 2003 to August 2004 in three sampling locations in the inner part of Boka Kotorska Bay varied widely. Nitrate concentration ranged from 0.0 to 2.42 mg/l at the surface and from 0.02 to 3.88 mg/l at the bottom, nitrate concentration from 0.02 to 0.21 mg/l at the surface and from 0.01 to 0.6 mg/l at the bottom, phosphate concentration from 0.03 to 0.18 mg/l at the surface and from 0.01 to 0.22 mg/l at the bottom, silicate concentration from 0.0 to 1.42 mg/l at the surface and 0.45 mg/l at the bottom respectively. Value of phytoplankton biomass, as represented by chlorophyll a, ranged from 1.02 to 8.68 mg/cubic meter and from 0.49 to 5.23 mg/cubic meter at the bottom. According to the UNEP criteria during the investigated period it can be concluded that the area in question is mesotrophic with the exception of December when it is eutrophic.
Afficher plus [+] Moins [-]Young fish find on mixed coastal water along Montenegrin coast [Adriatic sea, Montenegro]
2006
Joksimovic, A. (Institut za biologiju mora, Kotor (Montenegro)), E-mail: acojo@cg.ac.yu | Mandic, S. (Institut za biologiju mora, Kotor (Montenegro)) | Mickovic, B. (Univerzitet u Beogradu, Beograd (Serbia). Centar za multidisciplinarne studije) | Djurovic, M. (Institut za biologiju mora, Kotor (Montenegro)) | Pesic, A. (Institut za biologiju mora, Kotor (Montenegro)) | Mandic, M. (Institut za biologiju mora, Kotor (Montenegro))
Formation of ozonation byproducts in groundwater subjected to aeration/preozonation and coagulation
2006
Agbaba, J. (Prirodno-matematicki fakultet, Novi Sad (Serbia)), E-mail: agbaba@ih.ns.ac.yu | Dalmacija, B. (Prirodno-matematicki fakultet, Novi Sad (Serbia)) | Klasnja, M. (Tehnoloski fakultet, Novi Sad (Serbia))
This work considers the effect of the ozonation process on formation of aldehydes in groundwater pretreated by aeration/preozonation (2.0 g O3/cubic meter) and coagulation with polyaluminium-chloride (5 and 10 g Al/cubic meter). Experiments were carried out on a semi-industrial plant of 2 cubic meter/h capacity. It was found that in the course of ozonation NOM content shows a decrease (up to 54% TOC), whereas content of aldehydes increases by 1.0-14 microgram/L, depending on the water pretreatment and applied ozone dose. The most prominent changes in specific aldehydes content during ozonation were detected after applying ozone dosages of 0.5-2.0 mg O3/mg TOC.
Afficher plus [+] Moins [-]Adventage of ozonization in treatment of groundwater
2006
Kaut, I. (Vodovod i kanalizacija, Pancevo (Serbia)), E-mail: kaut@eunet.yu | Savic, Z. (Vodovod i kanalizacija, Pancevo (Serbia))
Treatment of groundwater with increase contents of ammonia, iron and manganese, needs more content of oxigen then realized in proceeding of aeration. Beside enriching water of oxigen, ozonization gives other important effects. For the first time, ozonization is practicaled on plant in Pancevo (Serbia), and it is base for define all of positive experiences. From this, we can recognize priorities of this proceeding, which will be aranged in this report.
Afficher plus [+] Moins [-]Caractérisation expérimentale et modélisation des effets des pratiques culturales sur la pollution nitrique d'un aquifère en zone de grande culture
2006
Beaudoin, Nicolas
Les eaux superficielles et souterraines doivent recouvrer une bonne qualité chimique et biologique avant 2015, d'après la Directive Cadre Européenne. Les Bonnes Pratiques Agricoles (BPA) établissent un compromis entre les risques de pollution et de perte de revenu. Le résultat minimal escompté est de respecter la norme de potabilité de 50 mgNO3.L-1 dans les eaux de captage et d'éviter les transferts de pollution de l'hydrosphère vers l'atmosphère. Cependant leur mise en oeuvre ne garantit pas d'atteindre ces objectifs ; cela nécessite des moyens de quantifier l'impact des pratiques agricoles effectives sur la pollution nitrique. Nous avons testé différentes méthodes de quantification, en nous appuyant sur les données issues d'une expérimentation partenariale de prévention de la pollution, menée sur le site de Bruyères (02). La question finalisée est "quel est l'impact des BPA, appliquées de façon systématique, à l'échelle d'un bassin"? La question de recherche est "peut-on modéliser la pollution nitrique, en situation agricole, à l'échelle du bassin hydrologique"? Le site d'étude est un plateau de 187 ha qui alimente une nappe d'eau souterraine, sise dans le Lutétien. Cette nappe alimente 5 sources principales qui connaissent une pollution croissante depuis 1970. Les 21 parcelles cultivées du plateau ont fait l'objet d'une mise en oeuvre systématique des BPA, par les 3 agriculteurs, depuis 1990. Les pratiques agricoles et l'hydrogéologie du site ont été caractérisées. Les débits des sources répondent aux pluies efficaces dans un délai d'une semaine. Le temps moyen de séjour de la molécule de Tritium dans l'aquifère est de 25 ans, à cause de l'épaisseur de la zone non saturée. Compte tenu de ce délai, un niveau intermédiaire d'évaluation est nécessaire : les pertes sous la zone racinaire. Les méthodes de quantification diffèrent selon leur degré de dépendance aux données expérimentales : i) le modèle de calcul LIXIM, associé avec toutes les données observées; ii) un modèle stochastique de réponse des cultures à la dose d'azote, initialisé annuellement; iii) le modèle fonctionnel dynamique STICS, qui peut simuler les pertes du système sol- plante- atmosphère de façon continue pendant plusieurs années. Les prédictions des variables d'intérêt économique et environnemental sont confrontées, aux données observées, aux échelles de la station et du bassin. Les impacts environnementaux et économiques, de différents scénarios de prévention de la pollution, sont simulés. Les reliquats d'azote minéral à la récolte et en entrée d'hiver sont proches et stables dans le temps avec respectivement 41 et 57 kgN.ha-1. L'intégration des flux calculés avec LIXIM, à l'échelle de la rotation culturale, conduit à lisser le facteur culture et à faire du type de sol le principal déterminant de la concentration. La teneur en nitrate moyenne pondérée, de l'eau de percolation, est de 46 mgNO3.L-1 pour la zone cultivée et de 37 mgNO3.L-1 pour l'ensemble du bassin. Ce bon résultat est confirmé qualitativement par la baisse constatée des teneurs de plusieurs captages depuis l'an 2000. Le temps de réponse de l'aquifère serait égal à la moitié de son temps de renouvellement. L'abattement de la teneur en nitrate de l'eau de percolation permis par les BPA, relativement à un scénario conventionnel, est compris entre 27 et 39 %, suivant la méthode de simulation. Le coût des BPA est de 0.07 | Surface and groundwaters must regain good chemical and biological quality before 2015 according to European Directives. Good Agricultural Practices (GAPs) establish a compromise between the risks of pollution and the loss of revenue. The minimum result expected is conformity with the drinking water standard of 50 mgNO3.L-1 in the collected water and the avoidance of transfer of pollution from the hydrosphere into the atmosphere. However their implementation does not guarantee that these objectives will be reached ; that requires a means of quantifying the impact of effective agricultural practices on nitrate pollution. We have tested different methods of quantification by using data from a collaborative experiment on pollution prevention, carried out on the site of Bruyères (02). The question targeted was « what is the impact of GAP, applied regularly, on the scale of a catchment area ? » The research question was « can nitrate pollution be modelled, in a farming situation, on the scale of a catchment area ? » The study site is a plateau of 187 ha which supplies a groundwater aquifer located in the Lutetian geological layer. This aquifer feeds five main springs which have suffered increasing pollution since 1970. The 21 cultivated fields on the plateau were subjected to regular implementation of GAPs by the three farmers since 1990. The farming practices and the hydrogeology of the site were characterised. The flow rates of the springs respond to effective rainfall after a delay of a week. The mean residence time of the tritium molecule in the aquifer is 25 years, because of the thickness of the unsaturated zone. In view of this delay, an intermediate level of evaluation is necessary : the losses under the root zone. The methods of quantification differ according to their degree of dependence on the experimental data : i) the LIXIM mathematical model, associated with all the observed data ; ii) a stochastic model of crop response to the nitrogen rate, initialised each year, iii) the functional dynamic model STICS, which can simulate the losses of the soil/plant/atmosphere system continuously over several years. The predictions of the variables of economic and environmental interest are compared with the observed data on the scale of the station and of the basin. The environmental and economic impacts for different scenarios of pollution prevention are simulated. The mineral nitrogen residues at harvest and at the beginning of winter are similar and stable over time at 41 et 57 kgN.ha-1 respectively. The averaging of the losses, calculated with LIXIM, over the crop rotation, smooths out the crop factor and makes the soil type the principal determinant of the concentration. The mean weighted nitrate concentration in the percolating water is 46 mgNO3.L-1 for the cultivated zone and 37 mgNO3.L-1 for the whole basin. This good result is confirmed qualitatively by the fall observed in the contents at several collection points since the year 2000. The response time of the aquifer would be equal to half of its renewal time. The reduction in the nitrate content of the percolation water permitted by GAPs, compared with a conventional scenario, is between 27 and 39%, depending on the simulation method. The cost of the GAPs is 0.07 €.m-3 of drinked water, making prevention competitive with water treatment at the Bruyères site. Dynamic modelling with STICS appears to be effective in the agricultural situation, but its reliability depends on the availability and relevance of the databases used to calibrate it. It can take account of a large number of technical inputs and their long-term interactions. Coupling STICS with a geographical information system (GIS) enables the spatial variability of the physical and cultural features of the environment to be integrated. However it is not possible to guarantee the reliability of the predictions for both any time and any place. Access to the precise value of parameters like the crop’s maximum rooting depth or the stock of organic nitrogen is simply not feasible. According to the STICS model, the nitrogen losses simulated in gaseous form are equal to those in solution. This result needs to be verified. Bearing in mind these limitations, modelling based on experimentation can become a management tool for nitrogen in cropping systems on a regional scale. The problem of limiting nitrate leaching is shifted towards the conception of sustainable cropping systems.
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