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131.
The risk assessment of genetically-modified plants pursuant to Annex II B of EU Directive 94/15/EC assumes that it is possible to infer the environmental impacts of a crop plant from its characteristics, so most of Annex II should also be applicable to conventional plants. To test this, we surveyed reports on the ecological impacts of the cultivation of non-transgenic crop plants with novel or improved traits and, in three cases, investigated whether Annex II B would have been adequate to indicate the effects. Such an assessment appears to be feasible only if the time frame on which it is based is short, so that long-term effects cannot be assessed. Secondly, the plant must be genetically homogenous which is not always granted, e.g. with forest-trees. Thirdly, the cultivation area must be defined. Differences in the behaviour of foreign plants between their original and cultivation habitats may be ecologically relevant and should be assessed. In the (few) cases where direct inference of the observed effects was possible from inherent traits, these effects often correlated with poor adaptation to local environmental conditions. The ecological impacts of traits that had been introduced in order to overcome poor adaptation may differ widely according to the way in which the traits are exploited. In practice, the effects of agricultural measures are more important than the effects of gene transfer and invasiveness, although the latter currently play a major role in risk assessment. In the light of these deliberations, a modification of Annex II B of EU Directive 94/15/EC is suggested.  相似文献   
132.
Regional Environmental Change - African land systems play a decisive role in addressing future sustainability challenges for food and energy supply—in Africa and potentially elsewhere....  相似文献   
133.
The biogenic fraction of a simple solid recovered fuel (SRF) mixture (80 wt% printer paper/20 wt% high density polyethylene) is analyzed with the in-house developed adapted balance method (aBM). This fairly new approach is a combination of combustion elemental analysis (CHNS) and a data reconciliation algorithm based on successive linearisation for evaluation of the analysis results. This method shows a great potential as an alternative way to determine the biomass content in SRF. However, the employed analytical technique (CHNS elemental analysis) restricts the probed sample mass to low amounts in the range of a few hundred milligrams. This requires sample comminution to small grain sizes (<200 μm) to generate representative SRF specimen. This is not easily accomplished for certain material mixtures (e.g. SRF with rubber content) by conventional means of sample size reduction.This paper presents a proof of principle investigation of the sample preparation and analysis of an SRF model mixture with the use of cryogenic impact milling (final sample comminution) and the adapted balance method (determination of biomass content). The so derived sample preparation methodology (cutting mills and cryogenic impact milling) shows a better performance in accuracy and precision for the determination of the biomass content than one solely based on cutting mills. The results for the determination of the biogenic fraction are within 1–5% of the data obtained by the reference methods, selective dissolution method (SDM) and 14C-method (14C-M).  相似文献   
134.
This article presents a comprehensive data set on Austria’s terrestrial carbon stocks from the beginnings of industrialization in the year 1830 to the present. It is based on extensive historical and recent land use and forestry data derived from primary sources (cadastral surveys) for the early nineteenth century, official statistics available for later parts of the nineteenth century as well as the twentieth century, and forest inventory data covering the second half of the twentieth century. Total carbon stocks—i.e. aboveground and belowground standing crop and soil organic carbon—are calculated for the entire period and compared to those of potential vegetation. Results suggest that carbon stocks were roughly constant from 1830 to 1880 and have grown considerably from 1880 to 2000, implying that Austria’s vegetation has acted as a carbon sink since the late nineteenth century. Carbon stocks increased by 20% from approximately 1.0 GtC in 1830 and 1880 to approximately 1.2 GtC in the year 2000, a value still much lower than the amount of carbon terrestrial ecosystems are expected to contain in the absence of land use: According to calculations presented in this article, potential vegetation would contain some 2.0 GtC or 162% of the present terrestrial carbon stock, suggesting that the recent carbon sink results from a recovery of biota from intensive use in the past. These findings are in line with the forest transition hypothesis which claims that forest areas are growing in industrialized countries. Growth in forest area and rising carbon stocks per unit area of forests both contribute to the carbon sink. We discuss the hypothesis that the carbon sink is mainly caused by the shift from area-dependent energy sources (biomass) in agrarian societies to the largely area-independent energy system of industrial societies based above all on fossil fuels.  相似文献   
135.
Journal of Material Cycles and Waste Management - With the rapid growth of healthcare waste and improvement of people’s environment awareness, the sustainability of healthcare waste...  相似文献   
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At the Sulm River, an Austrian lowland river, an ecologically orientated flood protection project was carried out from 1998-2000. Habitat modeling over a subsequent 3-year monitoring program (2001-2003) helped assess the effects of river bed embankment and of initiating a new meander by constructing a side channel and allowing self-developing side erosion. Hydrodynamic and physical habitat models were combined with fish-ecological methods. The results show a strong influence of riverbed dynamics on the habitat quality and quantity for the juvenile age classes (0+, 1+, 2+) of nase (Chondrostoma nasus), a key fish species of the Sulm River. The morphological conditions modified by floods changed significantly and decreased the amount of weighted usable areas. The primary factor was river bed aggradation, especially along the inner bend of the meander. This was a consequence of the reduced sediment transport capacity due to channel widening in the modeling area. The higher flow velocities and shallower depths, combined with the steeper bank angle, reduced the Weighted Useable Areas (WUAs) of habitats for juvenile nase. The modeling results were evaluated by combining results of mesohabitat-fishing surveys and habitat quality assessments. Both, the modeling and the fishing results demonstrated a reduced suitability of the habitats after the morphological modifications, but the situation was still improved compared to the pre-restoration conditions at the Sulm River.  相似文献   
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A stable isotope15N-nitrogen test (ESIMA = Ecotoxicological Stable Isotope Metabolic Assay) was developed to assess biological effects and the potential toxicological hazard of chemicals and contaminated environmental samples on plant metabolism. The assay measures the effect of toxicants on the incorporation of a15N labelled tracer into the total nitrogen fraction (both the nonprotein and protein fraction) of plants. Segments ofPisum arvense epicotyls are used as test substrates because of their high metabolic activity. The plant material is incubated under standardised conditions for two hours; subsequently15N incorporation is analysed by determining the15N abundance (15N atom-%) in the epicotyl segments. The effects of toxicants are evaluated by comparing the15N incorporation rates of control tissue and epicotyl segments exposed to individual chemicals or complex environmental samples. The specificity and sensitivity of effects as indicated by ESIMA were compared with effects as measured by two established ecotoxicological bioassays, the pollen tube growth test using pollen ofNicotiana sylvestris and the bacterial luminescence inhibition test using pollen ofPhotobacterium phosphoreum. The results of the study clearly indicate the suitability of ESIMA for assessing toxic impacts on plant nitrogen metabolism. Prof. Dr. habil. Hans Faust dedicated to his 70th birthday.  相似文献   
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