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1.
While the large amount of data available makes it possible to provide a statement concerning the effects of PCDD/PCDF on the WHO TEF-reappraisal regarding the observance of dioxin emission values from waste incineration, similar values for PCBs could not be determined accurately or could only be estimated roughly for the WHO, because only limited measurement values are available for these substances. Thanks to the present availability of such measurement values from the MVA in Bielefeld-Herford, Germany and the MVR in Hamburg, Germany, it is now possible to determine a direct relationship between the low PCDD/PCDF values and the 12 different PCBs which are taken into consideration by the WHO. As the results of these investigations have shown, the statement in Section 2 claiming that there are generally only very low levels of PCDD/PCDF emissions stemming from waste incineration plants, and that the 12 additional PCBs considered by the WHO as well as the WHO TEFs lead to no relevant increase in the evaluation/calculation of the actual emission values nor to a value above the dioxin (I-TEQ) threshold value as established in the 17th BImSchV (Germany Federal regulations responsible for protecting the population from emissions), can be confirmed. A dominant role of the WHO PCB-TEQs is seen to be played by the PCB-126. The exhaust gas measurements in waste incineration plants might therefore already be sufficient if merely the dioxin-like PCB-126 values were to be used in the calculation of the dioxin I-TEQ.  相似文献   

2.
The azaarenes and the structurally analogous PAH accompany each other and occur ubiquitously in nature. Photochemical conversions like direct photolysis or the photoreaction with nitrate are important natural degradation reactions of azaarenes. Furthermore, photoreactions with chlorine and bromine radicals can be expected in nature. The reactions generate a large number of oxidized, nitrated and halogenated products with unknown toxicity. In this paper, a first screening of changes is reported in acute toxicity during the course of the photochemical reactions. As test system luminescent bacteria are used. For quinoline, isoquinoline and phthalazine the investigations show different changes of the toxicity of the reaction mixtures in dependence on the respective reaction type. The toxicity of the reaction mixtures of quinazoline and quinoxaline increases in all reactions investigated. Furthermore the reactions of bromine radicals with azaarenes also show an increase of the toxicity in all cases. Compared with the azaarenes in all reactions products with significantly higher toxicity are formed.  相似文献   

3.
4.
A number of products, such as washing agents or pharmaceuticals, enter the hydrosphere mainly with municipal wastewater. In this case the predicted environmental concentrations (PEC) of substances are largely determined by their elimination in municipal wastewater treatment plants and by the dilution ratio of wastewater in the rivers. In this article some rough estimates of the wastewater ratio in German rivers are presented and as a starting point for a more complex model for calculating the PEC more exactly, data on the fluctuation of river flow rates are shown.  相似文献   

5.
The quality of regionalizations can only be evaluated with regard to its specific purposes. In environmental monitoring, regionalizations, besides being an analysis tool, has a great importance on the selection of monitoring sites. The article describes the relationship between regionalization, selection procedure and representativeness using the example of Ecological Area Sampling (EAS) and presents the regionalization which was tested in an EAS pilot study.  相似文献   

6.
Humic substances are an important component of organic carbon in natural waters. Their character and properties are determined by the sources and the processes of their origin. Humic substances are not exclusively refractory compounds, but they are involved in several transformation processes in the water. It is not possible to directly analyze humic substances, therefore several methods were applied for their characterization. The presented LC-OCD-technique is a size-exclusion-chromatography with online UV- and carbon detection. Carbon fractions, e.?g. humic substances were differentiated by their molecular size. The portion of humic substances in sediment porewaters of the rivers Elbe, Rhine, Danube, Oder, Müritz-Elde-Waterway was determined. With only a few exceptions it ranges from 50 to 67?% of the dissolved organic carbon. The high molecular weight fraction accounts for 10 to 34?%, and the fraction of the low molecular weight substances was from 7 to 37?%. The ratio between the spectral absorption coefficient (254?nm) and the organic carbon is called SUVA (L/mg × m) and is an inidicator of the proportion of unsaturated bonds in the humic substances. Both high molecular herbal components (e.?g. cellulose, lignin) and biological degradiation products (e.?g. amino acids, sugar) are involved in sediment porewater transformation and degradiation processes. This demonstrates the distribution of the dissolved organic carbon between the fractions.  相似文献   

7.
The stability of H+, NH 4 + , and PO 4 3? ions in rainwater samples was in vestigated under different conditions cf storage and transport. Microbiological and physicochemical processes account for changes. Suppression of microbiological activities in deposition networks using conventional analyses may be achieved by adding AgCl-powder and by cooling to +4 °C.  相似文献   

8.
Background, aim, and scope Polycyclic aromatic hydrocarbons (PAH) result from incomplete combustion of almost every organic materials, e.?g. due to forest fires, residential heating, combustion engines, grilling, or smoking. PAH are predominantly distributed over the air-path. Their usage in products (e.?g. moth-balls) has been limited strictly or completely forbidden in the past. In the context of the EU Water Framework Directive (WFD), the single substances anthracene, fluoranthene and naphthalene, as well as PAHs as group of substances, are listed as “priority” substances. Background of this work is a first compilation of sources of PAH emissions, and in this context, the collection of all relevant data and information to calculate the total emissions into surface waters in Germany. Materials and methods Within the scope of diverse research projects, funded by the German Environmental Agency, the available data material concerning PAH input in surface waters has been analyzed by the Fraunhofer Institute for Systems and Innovation Research. On the basis of the collected data, a first evaluation of relevance of the different sources has been conducted using the model MONERIS. Results As a result of the atmospheric deposition, PAHs enter, to a large extent, surface waters directly or indirectly through surface runoff (e.?g. urban areas, wastewater treatment plants, erosion). Discussion Although there is still additional research need for some of the covered PAH sources, a noticeable distribution pattern of relevance emerges. Conclusions The scenarios, based on the currently known sources, show that the implementation or the neglect of emission reduction measures in the field of diffuse air-borne PAHs are crucial for the further development of the deposition of PAHs in surface waters. More far-reaching studies are necessary, e.?g. concerning emissions from inland navigation/motor boats, the inhomogeneous source “products”, or the path “erosion”. Recommendations and perspectives According to the EU-WFD, all depositions, emissions and losses of “priority hazardous” classified substances, such as the group of PAHs, have to be stopped or gradually finished in the long term. Until the year 2015, environmental quality standards (EQS) have to be met for all “priority substances”. Presently, the EQS often are not completely fulfilled for many substances of the PAH group, including benzo(a)pyrene. Reduction measures are necessary within diverse areas, especially concerning diffuse atmospheric emissions (e.?g. “residential heating”).  相似文献   

9.

Goal and Scope

The constant increase of traffic and the rising energy and material consumption both in industry and trade as well as in private households mean a constant challenge to environmental protection and to the air pollution control. With the commencement of the Federal ambient pollution control act in April 1974, the legal basis for the monitoring of air pollution was created. In future, the limit values laid down in the Council Directive 1999/30/EG, 2000/69/EG and 96/62/EG, will be valid. In town and regional planning there is a great demand for a simple index to evaluate the air quality. From the available data of PM10, NO2, O3, CO, SO2, trends of the air quality will be derived.

Methods

The indices LQI and TLQ suggested by Mayer et al. (2002) were calculated for selected stations of the air pollution monitoring network (ZIMEN) in Rhineland-Palatine. All analysis are based on hourly recorded value, Mean values and frequency distributions are used for the interpretation. Furthermore, the characteristics and trends of the indices under different weather conditions were examined and discussed.

Results

The examination figures out that the air pollutions indices at all stations show similar patterns in the period between January 2001 and December 2002. Neither the LQI, nor the TLQ shows an annual variation. Existing variations are mainly controlled by the general weather situation and the air temperature. High values of the indices appear at extremely high or low mean daily air temperature. The absolute value of the air pollution index is determined by local pollution factors.

Outlook and Recommendations

Both indices are well suitable to evaluate the air quality and to assess the effects of state-aided measures for air pollutant control. Therefore, the indices TLQ and LQI should be published as an additional information in the world wide web.  相似文献   

10.
In streams with an agricultural source of catchment, insecticide contamination and hydrodynamic stress increased with the rate of surface runoff. In this investigation, surface runoff was responsible for an insecticide contamination of the water of up to 6 μg/lParathion and of suspended particles of up to 302 μg/kgFenvalerate. Surface runoff also induced an increase of discharge up to one order of magnitude over one day. As a consequence, the number of macroinvertebrate species was discreased by 73% and the species composition was modified. Laboratory and field investigations pointed out that insecticide contamination is the most relevant cause of these observed biological changes. This work describes the population dynamics of a sensitive species and, in addition, the strategies of survival of a tolerant species.  相似文献   

11.
Background, aim and scope The United Nations Framework Convention on Climate Change understands carbon fixation in forests as an important contribution for the reduction of atmospheric pollution in terms of greenhouse gases. According to the German forest inventory on carbon in biomass an amount of 191?t C/ha was roughly estimated, without any spatial differentiation. Therefore, the aim of this investigation was to statistically identify factors that are significant for the carbon fixation and to map the spatial patterns of C sequestration in the federal state North Rhine-Westphalia. Materials and methods Together with information on climate, elevation, vegetation, and deposition, data from two forest monitoring networks were analysed statistically. Geostatistics and the decision tree algorithms Classification and Regression Trees (CART) and Chi-Square Automatic Interaction Detection (CHAID) were applied to calculate surface maps from punctual data on C in vegetation, in dead wood and in soil. Whereas spatial autocorrelation could be detected for the C loads in the humus layers, no surface maps could be calculated for the C contents of the mineral soils and for the forest trees/dead wood. Here, CART and CHAID were used to derive decision trees that were applied on available surface data to predict C loads for the entire study area. Results About 19?t C/ha could be predicted for the humus layer, 67?t C/ha for forest trees/dead wood and 90.7?t C/ha for the soil. An overall mean of 177?t C/ha was calculated for North Rhine-Westphalia lying 14?t C/ha below the German wide mean. Discussion Compared to the calculated results in another investigation a total of 68?mio. t C for the above ground dendromass was estimated. This is 11?mio. t C/ha higher than the amount calculated in this study and may be due to the fact that this value includes the C-pools in both, the brushwood and herbaceous layer in their estimations. The average C concentration in the humus layer all over Germany was found to amount for 20.7?t C/ha which is slightly above the C storage calculated for North Rhine-Westphalia. In the same study a Germany wide C average of 87.9?t C/ha was calculated which is very close to the 90.7?t C/ha calculated in this study. Conclusions The surface estimations of the C-pools in the above-ground biomass, the humus layer and the mineral soil enable to map the efficiency of the C-bounding capacity regarding the fixation of the greenhouse gas CO2. The mean values derived in this study are in good accordance with estimations based on other techniques. Recommendations and perspectives The approach presented should be verified by application to Germany wide inventory data and by means of Regression Kriging. Furthermore, the C-fixation under climate change should be calculated by combining statistical methods and the dynamic modelling tool WASMOD.  相似文献   

12.
13.

Scopes and main features

In order to explain the behaviour of the artificial radioisotope137Cs towards landscape resources in the Saar-Lor-Lux-Region, the cross-border region between southwestern Germany/ Saarland, France/Lorraine and Luxembourg, regional distribution as well as downward translocation and depth functions of137Cs in the main soil substrates of forest ecosystems in the Saarland were investigated.

Results

The study shows that the highest137Cs activities are found in the north of the Saarland, whereas the south and south-eastern regions show distinctly lower concentrations of137Cs. Migration rates range between 0.25 cm/a and 1.0 cm/a. On an average, the highest migration rates were found in the clayey-silty substrates of the lime stone areas in theMuschelkalk regions (Middle Triassic) (0.66 cm/a), followed by the loamy substrates of Lower Permian clastic sediments (Unterrotliegendes) (0.53 cm/a) and the sandy substrates of theBuntsandstein areas (Lower Triassic sandstone) (0.41 cm/a). 90 to 95% of the137Cs activities in the clay-poor soils of the Unterrotliegendes and the Buntsandstein were traced in the upper 10 cm of the humus topsoil. The substrates of the lime stone areas (Muschelkalk), in contrast to this, reveal a137Cs activity of only 70–76% at the same depth.

Conclusions

Due to the fact that the primary and secondary pores of the soil pore system, in their function as translocation pathways, decrease with increasing soil depth, a significant reduction in the migration rates of137Cs can be expected with increasing soil depth. On the other hand, the maximal migration depth of 40 cm found in shallow soils on jointed parent material, as well as on sites with high groundwater tables, implies a possible contamination of near-surface groundwater.

Future outlook

Based on the results of this study, a permanent monitoring of137Cs was added to the long-term Soil Monitoring Program run by the Federal Administrative Office of Environment of the Saarland (Landesamt für Umweltschutz des Saarlandes)  相似文献   

14.
For the two biosphere-reserves of Schorfheide-Chorin and Spreewald in the Federal State of Brandenburg, Germany, we designed a concept for a monitoring program of ecosystems which is feasible and inexpensive, and whose methodical development is transferable to other large-scale protected areas. Beside the statistical analysis of hard GIS data, we systematically used additional criteria such as naturalness, scarcity and special management, a based on expert knowledge. Thus, after an inventory of the existing ecosystems, we selected the ecosystems to be monitored from the different ecosystem groups (i.e. woods and forests, fens, lakes, rivers, arable land and grasslands) based on the following four criteria:
  1. dominance,
  2. naturalness,
  3. nation-wide scarcity and
  4. special management.
We then combined the selected ecosystems with their relevant forms of landuse to so-called ecosystem-landuse-complexes, which reflect the natural conditions as well as the human impact in the biosphere reserves. This paper presents the selection of the ecosystem landuse complexes to be monitored. Thus, for both biosphere reserves, we obtained 32 ecosystem landuse complexes in woods and forests, 32 in fens, 53 in lakes, 7 in rivers, 23 in grasslands and 20 in arable land.  相似文献   

15.
16.
Using a simple chemodynamical model, the distribution of lipophilic organic contaminants between the solid (suspended particulate matter, sediment) and the aquatic phase in waters has been studied. For numerous organic contaminants found in the river Elbe, the partitioning between the solid and aquous phases has been calculated.  相似文献   

17.
18.
The compilation of ozone data for the federal states of Hesse and Northrhine-Westphalia (NRW) in Germany indicated that the concentration of ozone level slightly decreased during the years 1990–1998. The average concentration of ozone over forest areas is significantly higher than over cities. Only the maximum figures in the years approached one another. However, values passing the legal thresholds (180 μg ozone/m3) were two to three-fold higher over forests than over cities. The ozone concentration in air is inversely proportional to the traffic density. It is suggested that the lower NOx concentration over the forest than over cities is involved in the maintenance of the higher ozone-concentration over forest areas. In the cities, the ozone is reduced by NO to almost zero at night, whereas it is reduced by only about 50% over forests with lower NO concentrations. This reduction is only partially compensated in connection with the photolysis of NO2 and the subsequent oxidation of O2 to O3 during the day. The ozone situation is principally the same in the federal states of Hesse and Northrhine-Westphalia.  相似文献   

19.
20.
For assessing product system sustainability, ecological as well as economical and social criteria have to be considered. These are very different criteria and individual valuation plays an important role when they are being compared. This paper shows how the most important economic parameter, i.e. monetary cost, can be integrated into the ecobalances of product systems without individual valuation. To do this, the less costly of two different product systems is improved until it reaches the cost of the other. The two product systems are not compared on an equal technical basis (as is notmally the case), but on the basis of equal cost. The procedure can be explained using windows as an example, assessing their production, service life (with maintenance and heating) and recycling/disposal. Standard windows with good insulating properties made of PVC, wood and aluminium are taken as the starting point. When they are compared, the ecobalances of PVC and wood windows differ only slightly, with a little greater difference for aluminium windows. The ecobalance of the aluminium window, on the other hand, is significantly different from those of PVC and wood windows. The cost of the PVC window is much lower than that of the other two systems. Because of this, PVC windows are technically improved by introducing a more expensive but better insulating glass pane, leaving the PVC window system still cheaper than the other two systems, but with drastically improved ecobalance results. If product systems with different monetary costs are to be compared using ecobalances, we propose that this be performed on an equal economical rather than an equal technical basis. Monetary cost can thus be integrated into ecobalance studies.  相似文献   

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