Life cycle engineering im Automobilbau

Ecobalance represents the basic principle for an environmental analysis and the starting point for the possibility of achieving improvements. Using the criteria related to both technology and ecology, this method has been expanded upon by IKP/PE and, over the course of many years, has proven to be a satisfactory method for those fields associated with industry and research. Data banks and software systems have been designed and are today applied in industry. An expansion of the holistic balancing to include the ‘social’ dimension is currently being developed by the IKP. Today, ecological decisions in technically and economically-associated areas are continuously being developed which place more emphasis on the preliminary developments than on a purely retrospective analysis. Aside from the continuous, further developments of these types of analysis with regard to never technical questions as well as the integration of newer aspects of optimization based on life cycle information (e.g. production balancing), the goal of further work includes the preparation of process-chain information in the respective in preliminary developments related to the design. The automobile industry consequently plays a significant role here, as was also the case in the initial transformation of methodology which was carried out in the 1990s. Finally, these developments are additionally motivated through the new ordinances presented to be employed throughout the entire EU. The responsibility attributed to a product over the course of its entire lifetime therefore plays a more prominent role. This is also reflected in ordinances like those related to the redemption of old automobiles or in the WEEE of the electronics industry (Directive on Waste Electrical and Electronic Equipment).     

Anwendung energetischer und nicht-energetischer Ressourcen in Energiesystemen: Vergleichende Bewertung

Goal and Scope

Which impact does the use of non-energetic abiotic resources (ores, minerals, etc.) have in life cycles of energy systems based on biogenic and fossil fuels? Is this kind of resource use less or more environmentally harmful than the utilisation of energetic abiotic resources (mineral oil, natural gas, etc.) in the same life cycles? This paper aims at answering these questions. In Part 1, a methodology is presented and applied to the life cycles of selected energy systems. Part 2 presents and discusses the results.

Methods

The applied methodology has been explained in the Part 1. For the assessment of energetic abiotic resource use, a widely recognised method is used. For the assessment of nonenergetic abiotic resource use, no overall recognised methodological approach exists. That is why for this aspect two different methods are exemplarily applied and compared with each other.

Results and Conclusion

Results show that the two assessment approaches for non-energetic resource utilisation lead to qualitatively equal results. Nevertheless they differ considerably from each other in their absolute values. This makes obvious that there is still a need for further methodological research work on that issue. Nevertheless, both methodologies yield that the accumulated effect of ore and mineral use is considerably lower than the accumulated effect of fossil primary energy utilisation in all life cycles analysed. With the assumptions made, the use of non-energetic abiotic resources only plays a comparatively subordinate role in the environmental life cycle assessment of energy systems based on biogenic and fossil fuels.

Recommendation and Perspective

Results suggest that an important resource-related impact of biomass and fossil fuel powered energy systems is caused by their consumption of fossil primary energy resources. The impact of non-energetic resource use can be neglected in comparison to that. At the same time, results also make clear that there is still a considerable need for further methodical research aiming at a standardised assessment methodology for the use of non-energetic abiotic resources.     

Genetic sub-structure and intermediate optimal outcrossing distance in the marine angiosperm <Emphasis Type="Italic">Zostera marina</Emphasis>

The spatial distribution of genetic variability depends on the spatial patterns of clonal and sexual reproduction, gene flow, genetic drift and natural selection. Species with restricted dispersal may exhibit genetic structuring within populations with immediate neighbours being close relatives, and may show differentiation among populations. Genetic structuring of a species may have important genetic, evolutionary and ecological consequences including distance-dependent mating success. In this study we used microsatellite markers to show that clones of Zostera marina in a population in the Ria Formosa, Portugal, were aggregated and covered distances of up to 3–4 m. Clones within 4 m of each other exhibited significant and positive coancestry values, reflecting the limited seed dispersal of this species. Hand-pollinations between near (0–10.9 m), intermediate (11–32 m) and far (15 km) individuals resulted in similar levels of seed set, although the near pollinations had higher, although not statistically significant, levels of seed abortion during maturation. Seeds from intermediate-distance pollinations had a significantly higher proportion of seeds germinate and shorter germination time than both the near and far seeds. Similarly, the average number of seedlings produced per pollination, used as an overall estimate of fitness, was significantly greater for the intermediate distance when compared to both near and far pollinations. These results suggest that the genetic structuring observed may result in both inbreeding and outbreeding depression, which gives rise to an intermediate optimal outcrossing distance.     

Protective skin structures in shell-less marine gastropods

Skin and stomach epithelia of the four suborders of nudibranch gastropods (Mollusca, Opisthobranchia) are characterized by large intracellular ovoid disks, here called spindles. These spindles are an evolutionary novelty in the nudibranchs; in shell-less sacoglossan species they are missing. We here examined whether the distribution and occurrence of the spindles is consistent with the assumption of a protective role against discharging nematocysts of co-habiting and prey Cnidaria. Spindles were abundant in epidermal cells of regions exposed to nematocysts, such as the cerata, the lips, the edges of lamellate rhinophores, the surfaces of non-retractile gill-like organs, as well as in the stomach epithelium of eolid and dendronotacean species which feed on Cnidaria. While cells packed with spindles almost exclusively formed the epidermis of eolid and arminacean species, they were less numerous in the skin of dendronotacean and dorid species, where glandular cells predominated. The preponderance of either glandular or spindle cells suggests a dual complementary defense strategy, on the one side the production of mucus coats and aversive glandular secretions, on the other structural defensive devices that are cushion-like entities filled with inert grains.     

Cardenolide content,emetic potency,and thin-layer chromatography profiles of monarch butterflies,Danaus plexippus,and their larval host-plant milkweed,Asclepias humistrata,in Florida

Summary This paper is the fourth in a series on cardenolide fingerprints of monarch butterflies (Danaus plexippus, Danainae) and their host-plant milkweeds (Asclepiadaceae) in the eastern United States. Cardenolide concentrations ofAsclepias humistrata plants from north central Florida ranged from 71 to 710 µg/0.1 g dry weight, with a mean of 417 µg/0.1 g. Monarchs reared individually on these plants contained cardenolide concentrations ranging from 243 to 575 µg/0.1 g dry weight, with a mean of 385 µg/0.1 g. Cardenolide uptake by butterflies was independent of plant concentration, suggesting that sequestration saturation occurs in monarchs fed cardenolide-rich host plants. Thinlayer chromatography resolved 19 cardenolides in the plants and 15 in the butterflies. In addition to humistratin,A. humistrata plants contained several relatively non-polar cardenolides of the calotropagenin series which are metabolized to more polar derivatives in the butterflies. These produced a butterfly cardenolide fingerprint clearly distinct from those previously established for monarchs reared on otherAsclepias species. In emetic assays with the blue jay,Cyanocitta cristata, the 50% emetic dose (ED₅₀) per jay was 57.1 µg, and the average number of ED₅₀ units per butterfly was 13.8, establishing that this important south eastern milkweed produces highly emetic, chemically defended monarchs. Our data provide further support for the use of cardenolide fingerprints of wild-caught monarchs to make ecological predictions concerning defence against natural enemies, seasonal movement and larval host-plant utilization by monarch butterflies during their annual cycle of migration, breeding and overwintering.     

Prior experience with eggs laid by non-nestmate queens induces egg acceptance errors in ant workers

We studied the effect of prior experience to eggs laid by nestmate and non-nestmate queens on the acceptance of queen-laid eggs by worker wood ants, Formica fusca. We transferred eggs from a non-nestmate queen into colonies during early spring, when their own queen was recommencing egg laying. A few weeks later, workers from these “experienced” colonies accepted eggs of both familiar (44% acceptance) and unfamiliar (40%) non-nestmate queens much more than workers from control colonies (2%) that had only had previous contact with their own queen’s eggs. Thus, prior exposure to eggs laid by a non-nestmate queen induces much greater acceptance of all non-nestmate queen-laid eggs. Mechanistically, we hypothesize that exposure to eggs from several queens may increase acceptance by causing a highly permissive acceptance threshold of non-nestmate queen-laid eggs rather than by widening the template for acceptable queen-laid eggs. These novel results show that egg-discrimination behaviour in F. fusca is flexible and that workers respond to the diversity of eggs experienced in their colony.