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131.
Helmut Haenel 《Die Naturwissenschaften》1954,41(15):362-362
132.
133.
134.
Helmut Metzner 《Die Naturwissenschaften》1973,60(11):507-515
135.
Helmut Altner 《Die Naturwissenschaften》1985,72(2):57-61
In order to discuss the justified and humane demands for more animal protection in science we need first to achieve conceptual clarity. A simple separation of highly developed animals from less developed ones is hardly possible. Although we have no reliable way of assessing pain and suffering in animals we still have the responsibility for protecting them. However, scientists will always require animal experimentation in order to further the understanding of ourselves and to improve health. These experiments should follow strict guidelines. Concrete measures for animal protection must be adapted to each case and the consequences carefully thought out. 相似文献
136.
Helmut Hölder 《Die Naturwissenschaften》1975,62(12):545-554
The term “Jurassic” refers to a manifold rock series of an epoch in the earth's history and its organic enclosures, from which-despite the lack of detail -a picture of earth surface and its life at that time can be reconstructed. This article presents the position of research and the problems it faces, which are partly of an objective and partly of a methodical nature. 相似文献
137.
Helge Torgersen Gerhard Soja Ines Janssen Helmut Gaugitsch 《Environmental science and pollution research international》1998,5(2):89-93
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
138.
Frank M. Hauser Tim Metzner Thorsten Rößler Michael Pütz Steffen Krause 《Environmental Forensics》2019,20(1):13-25
The entry of illegally discharged waste into the sewage system can cause serious damage to sewage pipes and harm the public domain. Besides industrial and communal sources, discharges from clandestine laboratories are of special forensic interest. Aim of this study is to investigate the possibility to detect clandestine discharges of possibly hazardous waste directly at the point of discharge. Tests were performed at a facility where real wastewater was pumped in a controlled way through an open sewage pipe above ground. Chloride, ammonia, pH and conductivity electrodes were investigated for their ability to detect discharges of different types of waste. Waste samples were diluted up to 50 times in a static wastewater environment and pH, conductivity and chloride electrodes were able to distinguish all waste dilutions from blank wastewater. These three electrodes were then used for dynamic tests by placing them inside flowing sewage water and discharging different types of liquid waste ten meters upstream of them. Parameters of the waste discharges like volume, time interval and speed of discharge were varied and the responses of the electrodes were collected. The dynamic tests showed that these three electrodes were able to pick up different waste discharges in a real wastewater environment. It was found that a high sampling rate of the sensors would be required to connect a certain discharge to a specific household connection. These findings highlight the possibility to locate illegal discharges, coming from a variety of sources, using the waste discharge itself. 相似文献
139.
Archetypical patterns and trajectories of land systems in Europe 总被引:1,自引:0,他引:1
Levers Christian Müller Daniel Erb Karlheinz Haberl Helmut Jepsen Martin Rudbeck Metzger Marc J. Meyfroidt Patrick Plieninger Tobias Plutzar Christoph Stürck Julia Verburg Peter H. Verkerk Pieter J. Kuemmerle Tobias 《Regional Environmental Change》2018,18(3):715-732
Regional Environmental Change - Assessments of land-system change have dominantly focused on conversions among broad land-use categories, whereas intensity changes within these categories have... 相似文献
140.
Beyene A Kassahun Y Addis T Assefa F Amsalu A Legesse W Kloos H Triest L 《Environmental monitoring and assessment》2012,184(11):7053-7063
Although waste from coffee processing is a valuable resource to make biogas, compost, and nutrient-rich animal food, it is usually dumped into nearby water courses. We carried out water quality assessment at 44 sampling sites along 18 rivers that receive untreated waste from 23 coffee pulping and processing plants in Jimma Zone, Ethiopia. Twenty upstream sampling sites free from coffee waste impact served as control, and 24 downstream sampling sites affected by coffee waste were selected for comparison. Physicochemical and biological results revealed a significant river water quality deterioration as a result of disposing untreated coffee waste into running water courses. During coffee-processing (wet) season, the highest organic load (1,900?mg/l), measured as biochemical oxygen demand, depleted dissolved oxygen (DO) to a level less than 0.01?mg/l, and thus curtailed nitrification. During off season, oxygen started to recuperate and augmented nitrification. The shift from significantly elevated organic load and reduced DO in the wet season to increased nitrate in the off season was found to be the determining factor for the difference in macroinvertebrate community structure as verified by ordination analysis. Macroinvertebrate diversity was significantly reduced in impacted sites during the wet season contrary to the off season. However, there was a significant difference in the ratio of sensitive to pollution-tolerant taxa in the off season, which remained depreciated in the longer term. This study highlights the urgency of research exploring on the feasibility of adopting appropriate pollution abatement technologies to implement ecologically sound coffee-processing systems in coffee-growing regions of Ethiopia. 相似文献