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Life cycle assessment-based environmental product declarations (EPDs) require the inclusion of biodiversity impacts across the entire supply chain. The objective of this study is to test the applicability of a Scandinavian biodiversity assessment tool, developed specifically for use with EPD applications, in an African desert environment, linking the industry types power generation and mining. For this purpose, a GIS-based spatial analysis tool—the biotope method—was adapted to a framework approach which allowed the selection of more suitable, site-specific biodiversity indicators. The biotope method provides a step-by-step process of defining system boundaries, mapping biotopes, categorizing biotopes based on site-specific indicators, and evaluating change in biotope status “before” and “after” the impact. The development of site-specific indicators was piloted in this study and determined by the affected ecosystem and the status of knowledge on biodiversity in this geographic area. Thus plants were used as indicators for biodiversity, and red-list status and endemism constituted the prime criteria for conservation value of plants. This in turn represented the key criterion for classifying biotopes. The tested biodiversity assessment tool has potential for application in different environments and operational settings but leaves room for improvement by including secondary impacts in the assessment and using a wider range of taxa for indicators of biodiversity.  相似文献   
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Nudibranchs (Mollusca, Gastropoda) feeding on tentacles and polyps of Cnidaria thereby ingest both latent and discharged nematocysts (NCs) along with the food mass. In eolid nudibranchs (Opisthobranchia, Aeolidacea), many of the undischarged NCs are transported to terminal cnidosacs in their body appendages (cerata) and incorporated as kleptocnidae for defense. In the present report, the occurrence and fate of NCs in the digestive tracts of eolids is compared with hydrozoan-feeding dendronotacean nudibranchs (Opisthobranchia, Dendronotacea), which may show more basic stages in the evolution of cnidosacs. Tomographic reconstructions of the distal tips of cerata were composed from series of semithin light microscopic sections, utilizing 3D-surface rendering software. Doto acuta (Dendronotacea, Dotidae) does not have cnidosacs; transmission electron micrographs show that the NCs are digested in lysosomes of digestive gland cells. In contrast, species of the genus Hancockia (Dendronotacea, Hancockiidae) have several small cnidosacs in each ceras; they accumulate NCs in the digestive cells, as well as in the cnidosacs. Many of the cnidosacs were found open to the exterior with NCs in the process of expulsion. These and other structural details suggest assigning a function of expelling the NCs to the Hancockia spp. cnidosacs. It is proposed that cnidosacs similar to those of Hancockia spp. provide a clue to understanding how the defensive function of eolid cnidosacs may have evolved. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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Mixed contamination by organic and inorganic compounds in soil is a serious problem for remediation. Most laboratory studies and field-scale trials focused on individual contaminant in the past. For concurrent bioremediation by biodegradation and bioleaching processes, we tested metal-reducing microorganism, Geobacter metallireducens. In order to prove the feasibility of the coupled process, multiple-contaminated soil was prepared. Mineralogical analyses have shown the existence of labile forms of As(V) as amorphous and/or weakly sorbed phases in the secondary Fe oxides. In the biotic experiment using G. metallireducens, biodegradation of toluene and bioleaching of As by bacteria were observed simultaneously. Bacteria accelerated the degradation rate of toluene with reductive dissolution of Fe and co-dissolution of As. Although there have been many studies showing each individual process, we have shown here that the idea of concurrent microbial reaction is feasible. However, for the practical use as a remediation technology, more details and multilateral evaluations are required in future studies.  相似文献   
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The anthropogenic emission sources of methane (CH4) and nitrous oxide (N2O) in the Federal Republic of Germany were investigated. The object of the recently completed first phase of this research project was to summarize the present knowledge about the emission sources, make a first rough estimate of the emissions, identify the need for further research in the field, and - as far as possible - discuss the existing possibilities to reduce emissions. The main CH4 emission sources identified are the landfills, stock farming and pit mining, the main N2O sources are agriculture (including a minor contribution from animal wastes) and the production of adipic acid, the latter possibly being reducible by means of a new catalytic process. The total anthropogenic emissions of CH4 from Germany are estimated at 5.4 – 7.7 million tonnes per year, contributing a share of roughly 2 % to the world-wide anthropogenic emissions (350 million t/a). Those of N2O are estimated at 200 000 – 280 000 tonnes per year (world-wide 1.4 – 6.5 million t/a).  相似文献   
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