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501.
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503.
Contributing to the debate on the causes of Himalayan environmental degradation, the status and management of four watersheds
in the Upper Pokhara Valley were studied using information available from land use analysis, household surveys conducted in
1989 and 1992, deliberations held with villagers, and field observations. Accordingly, areas under forests and grazing lands
were found being depleted at relatively high rates between 1957 and 1978 due mainly to the government policy of increasing
national revenue by expansion of agricultural lands, nationalization of forests, steadily growing population, and dwindling
household economy. Despite the steady growth of population, this process had remarkably slackened since 1978, owing primarily
to remaining forests being located in very, steep slopes and implementation of the community forestry program. Forests with
relatively sparase tree density, however, and grazing lands in the vicinity of settlements have been undergoing degradation
due to fuelwood and fodder collection and livestock grazing. In many instances, this is aggravated by weak resource management
institutions. Being particularly aware of the economic implication of land degradation, farmers have adopted assorted land
management practices. Still a substantial proportion ofbari lands in the hill slopes is vulnerable to accelerating degradation, as the arable cropping system is being practiced there
as well. The perpetuation of the local subsistence economy is certain to lead, to a further deterioration of the socioeconomic
and environmental conditions of watersheds. To facilitate environmental conservation and ecorestructuring for sustainable
development, a broad watershed management strategy is outlined with focus on alleviating pressure on natural resources. 相似文献
504.
Karl H.E. Kroemer 《Journal of Safety Research》1983,14(3):131-136
Body dimensions are main determiners of equipment dimensions. Design for the “average user” is not suitable. Selected percentile values at the lower and upper extremes of the variable distribution determine minimum and maximum equipment dimensions or adjustment ranges. Interactions among design variables must be considered. This paper applies this rationale to the determination of major equipment dimensions of video display terminal (VDT) workstations. While the approach is generally usable, the specific data describing the U.S. population used in this paper indicate design ranges appropriate for North America. Since American body dimensions are quite comparable to most European data, the equipment dimensions should also be suitable for use in Europe. 相似文献
505.
506.
Karl Herrmann 《Die Naturwissenschaften》1958,45(5):111-112
507.
We explore the topic of restorative justice in organizations. The tradition of restorative justice directs attention to the aftermath of wrongdoing. We highlight three ways offenders (making amends), victims (extending forgiveness), and organizations (fostering reintegration) restore justice in the workplace. Our paper concludes with questions for future research and inquiry. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
508.
Lavorel Sandra Grigulis Karl Leitinger Georg Kohler Marina Schirpke Uta Tappeiner Ulrike 《Regional Environmental Change》2017,17(8):2251-2264
Regional Environmental Change - Land use and spatial patterns which reflect social-ecological legacies control ecosystem service (ES) supply. Yet, temporal changes in ES bundles associated with... 相似文献
509.
Rodrigo Navia Olga Rubilar M Cristina Diez Karl-Heinz Schmidt Gerhard Behrendt Karl E Lorber 《Waste management & research》2007,25(2):119-129
The volcanic soils of southern Chile have demonstrated a high capacity to adsorb environmental pollutants, but for an industrial application, a stable solid material is necessary. The objective of this work was to produce a stable ceramic material through a process involving volcanic soil-polyurethane foam produced with recycled polyethylene terephthalate (PET)-polyols, and further thermal treatment. The selected foam formulation with 35.4% volcanic soil (< 63 microm) seems to be the most suitable for thermal treatment, with temperature steps at 700, 850, 1000 and 1200 degrees C. The porous ceramic material obtained has a stable solid form and an improved chlorophenols adsorption capacity (comparable to natural zeolites) that makes it suitable for advanced wastewater treatment and landfill leachate depuration. 相似文献
510.
Biodegradation experiments of various polycyclic aromatic hydrocarbons were studied with mixed bacteria culture under aerobic conditions. An easy‐to‐handle clean‐up procedure was developed for PAH and their metabolites simultaneously as well as a gc‐ms‐method to identify and quantify these compounds. Anthracene and dibenzothiophene are completely degradable in an aqeous system, whereas biodegradation of benzo(k)fluoranthene and benzo(h)quinoline is possible only in an oil‐in‐water‐system with dodecane as cosubstrate. No degradation of nitronaphthalene was observed in aqueous systems. New metabolites are 2,3‐dihydroxybenzothiophene, hydroxybenzothiophenecarbonic acid and benzothiophenequinone for dibenzothiophene and hydroxyfluoranthenic acid for benzo(k)flouranthene. Whereas the former metabolites are degradable under the experimental conditions, the latter accumulates during the degradation experiment. The results are important for microbiological wastewater treatment, since knowledge of biodegradation processes is indespensable for the successful treatment of PAH‐containing wastewater. 相似文献