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71.
The greenhouse gases subject to emission reduction commitments under the UN Climate Convention include the fluorinated compounds sulphur hexafluoride (SF6), perfluorocarbons (PFCs) and hydrofluorocarbons (HFCs). The present study projects the emissions of these gases in Germany over the 1995–2010 period, with and without additional emission abatement efforts In the business-as-usual scenario, total emissions of the three fluorinated gases rise over the 1995–2010 period from 11,1 to 27.4 million tonnes CO2 equivalent. This rise is attributable to 72% to HFCs, used above all for refrigeration and stationary air-conditioning, for mobile air-conditioning, for blowing extruded polystyrene (XPS) foam and for one-component polyurethane (PU) foam. Soundproof glazing is the largest SF6 emission sector. Most PFC emissions come from semiconductor manufacturing and aluminium smelting. The reduction scenario does not achieve a stabilisation of fluorinated gas emissions either. The rate of growth is only slowed, with 11.1 million tonnes CO2 equivalent in 1995 growing to 14.9 million in 2010. The measures proposed to attenuate emissions growth are: mandatory equipment maintenance in refrigeration and stationary air-conditioning, refrigerant substitution of HFCs by CO2 in mobile air-conditioning, partial HFC substitution by CO2 in XPS foam blowing, 95% HFC substitution by flammable hydrocarbons in one-component PU foam. Complete SF6 phase-out is considered to be feasible in soundproof glazing. The PFC emissions of the semiconductor industry can be cut by 85% by new chamber cleaning technologies.  相似文献   
72.
Ausblick     

Beitragsserien 2008

Ausblick  相似文献   
73.
This study aimed at statistically investigating the association between the internal exposure of children and young adults to uranium (U) and epidemiologically relevant external determinants of exposure. The investigation was performed with data from two studies within the framework of the German health-related environmental monitoring program: The German Environmental Survey for Children (GerES IV) conducted by the Federal Environment Agency (Umweltbundesamt) with data on 1,780 children 3–14 years of age and their home environment and the German Environmental Specimen Bank (ESB, section: human specimens) with data on 2,253 students 20–29 years of age. Both studies provided data on the U levels in human urine for all probands. GerES IV furthermore provided an extensive environmental and demographic database on, e.g., U levels in drinking water. The data from GerES IV and ESB were linked by GIS to spatially relevant exposure information, including background values of U in stream sediments and in upper and lower soils, U levels in mosses and particulate matter in the lower atmosphere, precipitation and elevation as well as forest density. Bivariate correlation analysis and two decision tree models showed moderate but significant associations between U in human urine and U levels in drinking water, stream sediments and upper and lower soils. Future investigations considering additional epidemiologically relevant data sets may differentiate the results. Furthermore, the sample design of future environmental epidemiology studies should take the spatial evaluation of the data into greater account.  相似文献   
74.
75.

Purpose  

Climate warming can change the geographic distribution and intensity of the transmission of vector-borne diseases such as malaria. The transmitted parasites usually benefit from increased temperatures as both their reproduction and development are accelerated. Lower Saxony (northwestern Germany) has been a malaria region until the 1950s, and the vector species are still present throughout Germany. This gave reason to investigate whether a new autochthonous transmission could take place if the malaria pathogen was introduced again in Germany.  相似文献   
76.
77.
Background, Aim, and Scope The introduction of genetically modified plants (GMP) into the European agriculture primarily has been investigated in respect of economical aspects, its impacts on conventional crops, and direct or indirect effects on human health. Potential ecological impacts, especially their long term and large scale implications, were out of focus, usually. A special task is to protect the integrity of nature reserves. According to §?23 of the German Nature Protection Law (BNatSchG) nature reserves are to protect nature and landscape properties by preserving and developing existing as well as by re-establishing biotopes of wild and endangered species. According to §?34a of the BNatSchG the use of GMP has to be accompanied by an environmental impact analysis of possible risks like it has to be done in projects affecting the integrity of Flora-Fauna-Habitats (FFH) or European bird sanctuaries. Considering this, the joint research project “Recommendations for isolation distances concerning the cultivation of genetically modified plants in the neighbourhood of protected areas” which was promoted by the Federal Agency for Nature Conservation (BfN) aimed at describing possible risks for biocoenoses in conservation areas that could be caused by the cultivation of GMP in their vicinity and at evaluating measures which could mitigate or hinder negative effects. The article at hand concentrates on describing the implications which would emerge when introducing different isolation distances concerning the cultivation of herbicide resistant oil seed rape (HR-OSR) and insect resistant maize (B.?t.-maize) near protection areas. On the other hand, a methodology is introduced which was developed to classify the German nature reserves according to their potential endangerment by GMP cultivation and to minimise calculation efforts for modelling possible impacts. Materials and Methods In 2003, there were around 7,400 nature reserves which covered 3?% of the whole territory of Germany. A geographical information system (GIS) was used to integrate geometries of conservation areas, land use data (CORINE landcover), agricultural information on district level as well as a map of German ecoregions. At first, it was evaluated how much arable land for B.?t.-maize or HR-OSR cultivation would remain if introducing different isolation distances around nature reserves (NSG). Furthermore, the NSG were aggregated to several homogenous classes reflecting different levels of cultivation intensities in their vicinity and different geometric properties. This was realised calculating a geometric coefficient (GC) which describes the ratio of periphery and area of each NSG in order to abstract the risk of GMP invasion. The density of maize and rape cropping near the NSG was expressed by a cultivation coefficient (CC). According to regional agricultural surveys, this was calculated by adding up the area of maize and rape fields within a radius of 1,000?m (maize) and 4,000?m (rape), respectively, around the NSG. Results Considering an isolation distance of 1,000?m around the NSG, 90?% of the farmland in Germany would be available for GMP cultivation. 50?% would remain when establishing an isolation distance of 4,000 m. The combination of GC and CC resulted in a total of nine risk categories (RC) describing the potential risk of endangerment by GMP cultivation in the vicinity of NSG. Areas with highest risk were grouped in RC nine where the smallest NSG (+ GC) in the main cultivation areas of maize or corn (+ CC) were summarised. With a numerical proportion of 7?% those sites cover only 0.4?% of total area of all NSG. All nature reserves showing highest CC values had a total proportion of 60?%. Discussion The derivation of GC and CC was based on a hierarchical approach and was implemented by complex GIS procedures. This makes it easy to calculate additional values for different GMP, protection areas or isolation distances. The RC were useful for choosing representative modelling sites in order to minimise calculation efforts when modelling possible impacts of GMP cultivation in vicinity of nature reserves. Conclusions The assessment of isolation distances around protection areas should be performed for each area individually concerning the GMP specific effects and dispersal properties as well as the protected organisms and the main protection targets. Especially HR-OSR is critical because of its volunteers and hybridisation partners. Another main source of GMP dispersal into protection areas might be the contamination of conventional seeds with transgene OSR seeds. Recommendations and perspectives Before defining and applying particular measures in order to protect conservation areas from possible impacts due to GMP cultivation a political and societal discussion is necessary in order to assess which GMP induced impacts may be tolerated. This has to be supported by additional scientific studies based on empirical and estimated data evaluating possible dispersal distances of GM pollen and possible environmental impacts of released transgenes and their toxins. According to the EU Directive 2001/18/EC the cultivation of GMP should be accompanied by a case-specific monitoring and general surveillance, as well. It should be realised as soon as possible, since the release and the cultivation of GMP in Germany have been started, already. The monitoring should be complemented by the implementation of a web-based geoinformation system (WebGIS) which enables the compilation and evaluation of the data and relevant geodata.  相似文献   
78.
Ecological insights into the usually high complexity of interaction webs demand a simplification of their structure to concentrate on the most important interactions within a community. One way to achieve this goal is to use functional groups (FGs). Using simple and partial Mantel tests the vertical interactions between FGs from different trophic levels were studied both at a disturbed grassland site and at a similar but undisturbed site. The resulting interaction structures of both ecosystems were compared. (i) An approximately 50% higher vertical FG-connectance could be found in the undisturbed than in the disturbed grassland; (ii) a much higher percentage of significant correlations did exist between FGs in the undisturbed than in the disturbed system; and (iii) the disturbed grassland was characterized by more simply structured biotic interaction patterns. From these results it was concluded that (a) Mantel tests are a useful tool for detecting significant interaction patterns (web links) between FGs, and that (b) FG-connectance is a powerful measure of complexity and functional diversity of communities.  相似文献   
79.
Carbon and oxygen isotopes were determined on 40 recrystallized shells of Late Jurassic bivalves from the Lusitanian Basin of Portugal. In contrast with the oxygen isotopes, which exhibited considerable diagenetic distortion, the carbon isotopes are thought to preserve a record of the salinity of the Jurassic marginal marine seas in which these bivalves lived. The reconstructed palaeosalinities range from 35‰ (euhaline) to 5‰ (oligohaline). Comparing these values with the palaeosalinity reconstructed from a palaeoecological analysis of 17 stratigraphic levels within the basin, the independently derived values agree in most cases. Strongly differing values are explained as being due to biotic factors and to diagenetic distortion of the isotopic signal; they are less likely to be due to small-scale time-averaging or insufficient microstratigraphic sampling. On the whole, the carbon isotope analyses are thought to produce reasonable palaeosalinity values, although data from infaunal, originally aragonitic bivalves appear to be less reliable than those from epifaunal bivalves with a predominantly or exclusively calcitic shell. As diagenetic alteration of the carbon isotope signal is, however, unpredictable and biotic effects on the isotopic composition are insufficiently known, palaeosalinity reconstructions based on stable isotope data should be supported by palaeoecological data.  相似文献   
80.
The first appearance of bluetongue disease, a biting midge-borne viral infection of ruminants, in August 2006 in Germany struck farmers, veterinary departments and superior authorities, as well as disease and pest control managers completely unprepared. During the summer and autumn months of the past year, the virus spread across borders in the Netherlands, Belgium, Germany, France and Luxembourg, and was eventually demonstrated on more than 2000 farms where numerous cattle and sheep fell ill or even perished. According to our limited epizootiological knowledge on bluetongue disease, the management of the crisis was of minor success. Particularly with respect to the vectors of bluetongue disease, our information is so restricted that directed vector control is impossible at present. Basic data regarding distribution, ecology and behaviour of the various species of biting midges in Germany is lacking. However, in these times of globalisation and fundamental ecological and climatic changes, in which the spread/import and establishment of vectors of disease and the agents they carry must be expected, it is essential to initiate monitoring programmes. These should be integrated into the ongoing environmental monitoring and designed by using geographic information systems and surface geodata. The monitoring data should be used to calculate predictive GIS maps of the distribution of ceratopogonids in space and time as well as to perform risk assessments with regard to bluetongue disease or other diseases transmitted by arthropods.  相似文献   
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