Verglaste Filterstäube aus Müllverbrennungsanlagen

Solid waste residues from municipal solid waste incinerator flue gas cleaning systems basically consists of Al, Ca-silicates and metal oxides. At lower concentrations, environmentally harmful compounds such as alkali halide salts, heavy metals and traces of organic pollutants, e.g. PCDD, PCDF and PCB, are also present. For the reuse of the valuable materials (Al, Ca and metal oxides), an effective treatment technique for destroying the organic contaminants and separating the anorganic toxins from the non-toxic components has to be applied, which can only be achieved through thermal processing. Detailed investigations on vitrified electrostatic precipitator ash from municipal solid waste incinerator plants have shown promising results in regard to the mass balances, the chemical composition and the quality of the glass phase obtained.     

Modeling the Effects of Habitat Fragmentation on Source and Sink Demography of Neotropical Migrant Birds

Many songbird populations in the midwestem United States are structured as a network of sources and sinks that are linked by dispersal. We used a modeling approach to examine explicitly how populations respond to incremental fragmentation of source habitat and how this response may vary depending upon two life-history attributes: fidelity to natal habitat type and reproductive strength of the source. Fragmentation of source habitat led to a predictable decline in population for both attributes examined, but the manner in which populations declined varied depending upon the reproductive strength of the source and the level of fidelity. When the source was weak and produced few excess individuals, fragmentation of source habitats resulted in a predictable and parallel population decline of adults in both the source and the sink. In this situation high fidelity to natal habitats was important for maintenance of population size and structure. Low fidelity to weak sources resulted in population extinction; populations experienced a demographic cost by dispersing from high quality source habitat to low quality sink habitat. In contrast, when the source was strong and produced many excess individuals, fragmentation of the source led to population declines in both the source and the sink, but this decline was more abrupt in sink habitats. When the source was strong and produced a large excess of individuals, nonfidelity to natal habitats had little effect on metapopulation size and structure.     

Economists' opinions on environmental policy instruments: Analysis of a survey

Incentive instruments (effluent charges) are theoretically expected to be preferred to direct regulations (individual emission ceilings) by university-employed, theoretically inclined politically right-wing, professional economists living in a market-oriented country, ceteris paribus. Public sector employed, politically left-wing, professional economists living in a country with a long tradition of government involvement prefer the regulatory approach, ceteris paribus. These theoretical hypotheses tend to be supported by a bivariate probit analysis based on a survey of more than 1400 economists in five countries.     

Untersuchungen zur Charakterisierung von Brandrauch

The aim of this work is to clarify if there is a correlation between fuel and its organic combustion products. To acquire homogenous data sets for our investigations, we analysed only the measurements of the “Forschungsstelle für Brandschutztechnik” at the University of Karlsruhe. All compounds with a similar structure were grouped and structural indices were ascribed to them. This also made it possible to obtain information about the frequency of occurrence of a set of substances in fire smoke. The kind of analytical measurements used by this institute provided no or only little information about inorganic compounds, highly volatile substances like acrolein or vinyl chloride, and very poorly volatile substances (e.g. polycyclic aromatic hydrocarbons). We found that benzene, methylbenzene, ethenylbenzene and ethylbenzene are always present in fire smoke. The formation of these typical compounds is described by a model. Aside from these compounds which are typically related to the smoke from fires, substances are always observed which are typical for a distinct fuel. Many compounds which are expected to be in the smoke are highly carcinogenic. Therefore, it is necessary for people with a high exposure to the smoke of fires, e.g. firemen, to protect themselves efficiently. In order to obtain more information about the risks to health of fire smoke, toxicological investigations will be necessary.     

Assessment of a General Finite Line Source Model and CALINE4 for Vehicular Pollution Prediction in Ireland

A comparative evaluation of two Gaussian-based line source models namely, California line source dispersion model version 4 and the general finite line source model, is presented. The concentrations predicted by these models are compared with background-corrected ambient concentrations measured at three different distances from a motorway and performance of both models assessed in the context of integrated transport–environment modelling for regulatory purposes.     

Antagonistic interactions between plant competition and insect herbivory

Interspecific competition between plants and herbivory by specialized insects can have synergistic effects on the growth and performance of the attacked host plant. We tested the hypothesis that competition between plants may also negatively affect the performance of herbivores as well as their top-down effect on the host plant. In such a case, the combined effects of competition and herbivory may be less than expected from a simple multiplicative response. In other words, competition and herbivory may interact antagonistically. In a greenhouse experiment, Poa annua was grown in the presence or absence of a competitor (either Plantago lanceolata or Trifolium repens), as well as with or without a Poa-specialist aphid herbivore. Both competition and herbivory negatively affected Poa growth. Competition also reduced aphid density on Poa. This effect could in part be explained by changes in the biomass and the nitrogen content of Poa shoots. In treatments with competitors, reduced aphid densities alleviated the negative effect of herbivory on above- and belowground Poa biomass. Hence, we were able to demonstrate an antagonistic interaction between plant-plant interspecific competition and herbivory. However, response indices suggested that antagonistic interactions between competition and herbivory were contingent on the identity of the competitor. We found the antagonistic effect only in treatments with T. repens as the competitor. We conclude that both competitor identity and the herbivore's ability to respond with changes in its density or activity to plant competition affect the magnitude and direction (synergistic vs. antagonistic) of the interaction between competition and herbivory on plant growth.     

Mapping atmospheric depositions of cadmium and lead in Germany based on EMEP deposition data and the European Moss Survey 2005

Background

The vertical migration of phytoplankton was investigated in natural waters using in situ fluorescence profiling, chlorophyll a concentrations and life counts at two study sites differing in coloured dissolved organic matter (cDOM) concentrations. The data from the corresponding water depths (50-cm intervals down to 10 m) and times (hourly, before dawn to sunset, several days) were related to the highly resolved (2 nm) underwater ultraviolet radiation (UVR)/photosynthetic active radiation (PAR) transparency (290 to 700 nm).

Results

Chlorophyll a maxima of mainly motile dinoflagellates were observed in situ at all days and at both study sites (open marine, brackish waters), independent on prevailing weather conditions or cDOM concentrations. Phytoplankton migration was triggered solely by irradiance in the 400- to 700-nm wavelength range (PAR) at the particular water depth, irrespective of PAR/UVR ratios and surface UVR (290 to 400 nm), after an illumination period of about 40 min. Interestingly, the PAR tolerance levels of the phytoplankton, which have been lower in cDOM-rich waters, matched their light acclimation values determined by parallel PAM measurements.

Conclusions

The response of the phytoplankton to PAR is not a sufficient protection strategy versus increasing UVR levels, which might have wide ecological implications beyond the level of primary producers to impact important ecosystem functions such as the delicate trophic interactions.     

Application of Ecological Classification and Predictive Vegetation Modeling to Broad-Level Assessments of Ecosystem Health

The Little Missouri National Grasslands (LMNG) of western North Dakota support the largest permitted cattle grazing use within all lands administered by the USDA, Forest Service, as well as critical habitat for many wildlife species. This fact, coupled with the need to revise current planning direction for range allotments of the LMNG, necessitated that a broad-level characterization of ecosystem integrity and resource conditions be conducted across all lands within the study area (approximately 800,000 hectares) in a rapid and cost-effective manner. The approach taken in this study was based on ecological classifications, which effectively utilized existing field plot data collected for a variety of previous inventory objectives, and their continuous spatial projection across the LMNG by maps of both existing and potential vegetation. These two map themes represent current and reference conditions (existing vs. potential vegetation); their intersection allowed us to assign various ecological status ratings (i.e., ecosystem integrity and resource condition) based on the degree of departure between current and reference conditions. In this paper, we present a brief review of methodologies used in the development of ecological classifications, and also illustrate their application to assessments of rangeland health through selected maps of ecological status ratings for the LMNG.