Anwendung der Hasse-Diagrammtechnik

Using four dynamic criteria, the following environmental changes were evaluated: Global warming; destruction, of the stratospheric ozone layer; eutrophication and acidification of aquatic ecosystems; photochemical smog; reduction of the available area of agricultural soils; loss of species diversity; consumption of resources; reduction of crop yield; forest decline; noise, and smell. These ecosystem changes, or negative effects, were characterized by four dynamic criteria: 1) Regional importance, 2) extent of alteration, 3) resilience and 4) irreversibility. A multi-criteria assessment, accounting simultaneously for all four criteria, requires a generalized concept of order. Here, the concept of partially ordered sets, visualized by Hasse diagrams, was used to derive a priority list of environmental changes. Highest priority was equally assigned to the loss of species diversity, the consumption of resources and the destruction of the ozone layer. However, these ecosystem changes are incomparable to each other concerning the four criteria used and thus require different management strategies.     

A relict trematosauroid (Amphibia: Temnospondyli) from the Middle Jurassic of the Junggar Basin (NW China)

A temnospondyl ilium from the uppermost Toutunhe Formation (Middle Jurassic, Callovian) of the southern Junggar Basin is described. Among the known temnospondyls it is very unusual in morphology because of its very long and slender shaft. It compares closely only to the ilium of one of the latest known trematosaurids from the Ladinian of southern Germany. The Toutunhe Formation has also yielded vertebrae and skull fragments of temnospondyls which belong to the brachyopid Gobiops from the Upper Jurassic of Mongolia. Brachyopoid ilia do not, however, display a morphology similar to that of the new specimen. It is therefore concluded that this specimen represents a second taxon of temnospondyl from the Toutunhe Formation, which probably represents the latest surviving trematosauroid. The Trematosauroidea, which was hitherto exclusively known from the Lower to early Upper Triassic, therefore joins the Brachyopoidea – and possibly the Capitosauroidea – as another group of temnospondyls which survived the end-Triassic mass extinction.     

Nitrifying community analysis in a single submerged attached-growth bioreactor for treatment of high-ammonia waste stream.

This study investigated the nitrifying community structure in a single-stage submerged attached-growth bioreactor (SAGB) that successfully achieved stable nitrogen removal over nitrite of a high-strength ammonia wastewater. The reactor was operated with intermittent aeration and external carbon addition (methanol). With influent ammonia and total Kjeldahl nitrogen ranging from 537 to 968 mg/L and 643 to 1510 mg/L, respectively, 85% nitrogen removal was obtained, and effluent was dominated by nitrite (NO2-/NOx > 0.95). Nitrifying community analysis using fluorescence in situ hybridization (FISH), with a hierarchical set of probes targeting known ammonia-oxidizing bacteria (AOB) within beta-proteobacteria, showed that the AOB community of the biofilter consists almost entirely of members of the Nitrosomonas europaea/eutropha and the Nitrosococcus mobilis lineages. Image analysis of FISH pictures was used to quantify the identified AOB, and it was estimated that Nitrosomonas europaea/eutropha-like AOB accounted for 4.3% of the total volume of the biofilm, while Nitrosococcus mobilis-like AOB made up 1.2%; these numbers summed up to a total AOB fraction of 5.5% of the total volume on the biofilm. Nitrite-oxidizing bacteria (NOB) were not detectable in the biofilm samples with probes for either Nitrospira sp. or Nitrobacter sp., which indicated that NOB were either absent from the biofilters or present in numbers below the detection limit of FISH (< 0.1% of the total biofilm). Nitrite oxidizers were likely outcompeted from the system because of the free ammonia inhibition and the possibility that the aeration period (from intermittent aeration) was not sufficiently long for the NOB to be released from the competition for oxygen with heterotrophs and AOB. The nitrogen removal via nitrite in a SAGB reactor described in this study is applicable for high-ammonia-strength wastewater treatment, such as centrate or industrial wastes.     

Investigation on the chemical structure of nonextractable residues of the fungicide cyprodinil in spring wheat using 13C-C1-phenyl-cyprodinil on 13C-depleted plants-an alternative approach to investigate nonextractable residues

13C-labelled cyprodinil was applied on 13C-depleted wheat plants with 27-fold field application rate. A control experiment applying same amounts of 14C-cyprodinil showed that main portions of the residues were detected in the cellulose (15% NER), hemicellulose (28.3% NER), and lignin fraction (23.3% NER). 16.7% were detected in water soluble polymers, 6% in both, pectin and protein fraction, and 4% in the starch containing fraction. Free cyprodinil was detectable by TLC in all fractions except lignin. A direct characterization of the residues in vivo by CP-MAS was not successful. Cell wall fractions were further analysed by liquid state NMR to determine the structure of the mobilized highly polymer/polar residues: Within lignin, where most of the residues were located at field application rate, neither intact cyprodinil nor its metabolites could not be detected. The 13C-label introduced was probably incorporated in the polymer as natural lignin monomers and thus are not considered as bound residues according to IUPAC definition.     

Internationally harmonized approach to biomonitoring trace element atmospheric deposition

The International Atomic Energy Agency (IAEA) has been systematically supporting work on biomonitoring air pollution using plants since 1997. Such studies are presently being supported by the IAEA in 14 countries within a co-ordinated research project. The main emphasis of this project is on (1) identification of suitable biomonitors of atmospheric pollution for local and/or regional application, and (2) their validation for general environmental monitoring, whenever possible. Although the participants are using different plants as biomonitors in their research in geographically and climatically diverse parts of the world, they are harmonising sampling approaches and analytical procedures. In this paper, an overview of these activities is given, along with the details, where possible. In all of these activities, proficiency testing and analytical quality assurance are important issues, which merit special attention. Within the scope of an intercomparison exercise, two lichen materials were distributed among the participating laboratories and a proficiency test was organised. The results obtained proved satisfactory performance for most participating laboratories.     

Use of 15N-depleted artificial compost in bound residue studies

Association of bound residues to soil humic matter may be accomplished by different binding mechanisms such as sequestration in hydrophobic interiors of the organic material or covalent linkage to the organic matter. The structures and chemical environments of compounds can be observed by NMR spectroscopy. We applied 15N-NMR spectroscopy to study the soil-bound residues of 15N-labeled simazine. As the 15N-isotope has a low sensitivity and natural abundance 15N-NMR experiments require long measurement times and often result in low signal-to-noise (S/N) ratios. Therefore, in addition to the use of 15N-labeled simazine, 15N-depleted compost was used to reduce the amount of background signal and enhance the sensitivity. The compost was produced from maize and wheat plants grown on sand with 15N-depleted NH4NO3 as sole nitrogen source. The plants were freeze-dried, ground and mixed with sand for composting. After a composting period of 224 days analysis of the compost revealed a 15N-content of 267 ppm as opposed to a natural abundance of 3650 ppm. Characterization of this artificial compost produced parameter values similar to those of a natural compost. The 13C-NMR-spectra of the humic and fulvic acids during different stages of maturity showed that there was a shift from single-bond functional groups to more complex double-bond and aromatic structures. Experiments with this compost showed an increased signal intensity. The improved sensitivity made it possible to obtain interpretable NMR signals in contrast to experiments with 15N-simazine on native soil where no signals were detectable. The data indicated that the bound residues of simazine are composed of metabolites resulting from N-dealkylation and triazine ring destruction. Silylation of the bound residues showed a very strong binding of the residues to the matrix as only a small fraction could be solubilized.     

Der VG?D 2005 im überblick

Ohne Zusammenfassung     

Remote monitoring of air pollutant emissions from point sources by a mobile lidar/sodar system

This paper describes remote monitoring of air pollutant emissions by a mobile lidar (light detection and ranging)/ sodar (sound detection and ranging) system. First, measurements are carried out in the flue gas plume of a public power plant. The investigations focus mainly on quantifying SO2 emissions, but the uncertainties of such measurements are also emphasized. Furthermore, an example providing valuable data sets for the development and validation of plume dispersion models is outlined with measurements of the dilution of SO2 along the plume axis. Series of repeated determinations of SO2 emissions show a large variation in the obtained flux values, with moderate margins of error. Incomplete recording of the plume within the individual lidar scans, induced by strong looping movements of the flue gas plume, predominantly causes the variations of flux values. Therefore, the highest flux values determined are considered to be the most exact. This is verified by a comparison of measured fluxes with in situ measurements made by the plant operators. The results further indicate that lidar measurements illustrate the location and dimension of aerosol plumes better than the location and dimension of the plumes of gaseous compounds. The wind direction affecting the plume at any moment can be determined faster by lidar than by sodar because the latter requires much longer time intervals of signal averaging. Measurements show higher concentrations of SO2 compared with results from a Gaussian plume model for periods of less than 5 min after dispersion. The findings emphasize the suitability of remote sensing for detecting emissions and for investigating the propagation and dilution of air pollutant plumes.     

Application of ground-based Lidar for studies of the dynamics of ozone in a mountainous basin

A ground-based Differential Absorption Lidar was employed to study the dynamics of atmospheric O3 within the planetary boundary layer of a basin in the 'Fichtelgebirge' mountains, NE Bavaria. In particular, the night-time dynamics of O3 linked to the ground were investigated. The Lidar system measured vertical profiles of O3 up to 1 km above ground. For detailed analysis of the night-time dynamics of ozone, supplementary data from three ground-based stations (measuring mixing ratios of O3 and NO(x), as well as meteorological parameters) are essential. The Lidar results could be evaluated with these data from various altitudes above the basin floor. For the station with the largest (vertical) distance to the ground-based Lidar, the agreement was very good at all times. The Lidar method proved to be useful for examining the spatial distribution of O3. The observed night-time decrease of O3 at the bottom of the basin was due to deposition and to advection of air masses containing less O3 from the mountain slopes.     

Surface solar ultraviolet radiation: A theoretical approach of the SUVR reaching the ground in Athens, Greece

Daily total ozone observations made during 1985–1993 by both the Total Ozone Mapping Spectrometer (TOMS) flown on the Satellite Nimbus-7 and the Dobson Spectrophotometer have been used in order to investigate the fluctuations of the daily broad-band and spectral solar ultraviolet radiation reaching the ground. This investigation has been performed by employing a recently developed parametric algorithm for the estimation of the spectral and broad-band solar ultraviolet radiation which takes the total ozone variations into consideration. Total ozone reductions during the summertime from 1985 to 1993 over Athens, Greece (37.6° N, 23.4° E), cause an increase in the ultraviolet irradiance which reaches the ground of 0.54 %, 0.98 %, 2.60 % and 0.79 % per decade for the months of July at 300 nm, 312 nm, 320 nm and UVB (280-320 nm), respectively.