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721.
The 19th century and first half of the 20th century is one of those periods in history of rapid economical, technical and social changes. There is an ongoing mechanization, followed by a movement to rationalize production and to make it cost effective. This has created a heavy burden of occupational deaths amongst workers. In this period occupational safety is developing into a professional field. Engineers are enclosing hazards and fencing heights, shaping up safety technique, and writing very practical publications on occupational safety. These publications, predominantly published in the United States, are leading to quite some safety related metaphors, with the iceberg and the domino’s as the most famous ones. Sociologists, psychologists, and physicians are more concerned with questions related to accident causation, and these specialists are conducting research leading to two different safety theories. Causes of occupational accident are found either in the workers’ capacity to handle hazardous situations, or in external causes, like very long working hours, dangerous machines and the increased pressures of work and speed of production. The Pittsburgh survey, the first extended analysis of occupational accidents in a steel district, strongly advocated the environmental hypothesis, while the so-called ‘individual hypothesis’ is favored by the American Safety First Movement, starting as a private initiative in 1906 by US Steel, and later spreading out over Western European countries. The British Industrial Fatigue Board has given the individual hypothesis its scientific justification. Despite scientific criticism just after World War II on the concept of accident proneness and ‘unsafe acts’, its popularity is not fading. Even nowadays the famous metaphors are still part of the vocational training of safety experts, also in The Netherlands. Apparently professional and scientific developments in occupational safety are belonging to two separate worlds. Before World War II, The Netherlands is not a leading country in occupational safety but a follower, first of France and the German speaking countries. After World War I its focus is directed towards the Anglo-Saxon countries. 相似文献
722.
Environmental Management - Cattle degrade streams by increasing sediment, nutrient, and fecal bacteria levels. Riparian fencing is one best management practice that may protect water quality within... 相似文献
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Rita Santos Ronald Wennersten Eduardo B.L. Oliva Walter Leal Filho 《Journal of environmental management》2009,90(12):3708
The competitiveness, in terms of macro and micro levels of an enterprise, is often dictated by its capacity to innovate, ability to respond to the needs of the market, and resilience to challenges from competition. This paper reviews the literature on the adaptation of research and development (R&D) units in subsidiaries of multinational corporations. It focuses mainly on the impact of the technological dynamic on sustainability performance of the Brazilian subsidiary of the Swedish multinational Ericsson. Through a conceptual framework, it explores information and communication technologies (ICT) towards a transversal and comprehensive vision of levels of innovation and sustainability. 相似文献
726.
Hartmut Koehler Tobias Frische Ingo Dobner Peter Behrend Maike Schaefer Heidi Taubner Bernd Jastorff Jürgen Warrelmann Ulrich Walter 《Environmental Sciences Europe》2001,13(5):291-300
Results of a field experiment (please refer to Warrelmann et al. 2000a) document TNT-degradation and regeneration after the establishment of a phytoremediation. Various approaches are included in a complex monitoring system, which are conducted in the field (nitroaromatics in soil, seepage water, and plants; soil fauna; soil fungi; decomposition) as well as in the lab (a battery of 6 biotests). The data document a high heterogeneity of the TNT-contamination, a rapid initial decrease and a mediocre displacement of nitroaromatics in plants and seepage water. The initial rapid transformation of TNT to aminodinitrotoluenes ceases significantly after 3 months. Results of the biotest battery allow a sophisticated assessment of soil toxicity; the results from the soil ecological field investigations make the long-term effects of TNT-contamination likely. In a third part of the series of articles, a synopsis and judgement of the project will be delivered. 相似文献
727.
River habitat monitoring and assessment in Germany 总被引:1,自引:0,他引:1
Whereas assessing the biological and chemical quality of water is a standard environmental procedure in many countries, the use of habitat survey methods that assess the ecomorphological quality of rivers is relatively new. In Europe, the EC Water Framework Directive requires such assessment from all EU Member States. In Germany, the first river habitat assessments were introduced in the late 1990 s. Each federal state develops its own river habitat map using the 'On-site Survey' and/or the 'Overview Survey'. The assessment describes the difference of the actual condition from a previously defined reference condition. In practice, a defined 'potential for restoration', a more realistic condition, makes restoration activities much easier and more successful. In Germany, the first River Habitat Map 2001 was published in 2002. The survey covered 33,000 km of river length, which equates to 10% of all rivers. A wide range from 'Undisturbed' (class 1) to 'Totally Disturbed' (class 7) river units exists; 77% of them are 'Clearly Disturbed' (class 4) or in worse condition. These result reflects extensive anthropogenic impact on the environment in general, but also past intense technical river 'improvements' that focused on the protection of settlements and traffic routes from flooding, better shipping conditions, the use of water power, and drainage of floodplains for agriculture and urban development. For comparability of survey results between EU Member States, a harmonization of national survey methods is in progress. A crucial point here is the definition of the reference condition for each river (near-natural conditions), since it influences the survey results. 相似文献
728.
Heininger P Höss S Claus E Pelzer J Traunspurger W 《Environmental pollution (Barking, Essex : 1987)》2007,146(1):64-76
Nematode communities of eight sites from three river catchments were investigated in terms of the genera composition, feeding types, and life-history strategists. The sampling sites showed a gradient of anthropogenic contamination with heavy metals and organic pollutants being important factors in differentiating the sites. Nematode community structure was related to sediment pollution and the hydro-morphological structure of the sampling sites. Heavily contaminated sites were characterized by communities with high relative abundances of omnivorous and predacious nematodes (Tobrilus, c-p 3; Mononchus, c-p 4), while sites with low to medium contamination were dominated by bacterivorous nematodes (Monhystera, Daptonema; c-p 2) or suction feeders (Dorylaimus, c-p 4). The relatively high Maturity Index values in the heavily polluted sites were surprising. Nematodes turned out to be a suitable organism group for monitoring sediment quality, with generic composition being the most accurate indicator for assessing differences in nematode community structure. 相似文献
729.
Marlen D. Eve Kris M. Havstadt Walter G. Whitford Marlen D. Eve 《Environmental monitoring and assessment》1999,54(3):205-227
Considerable evidence documents that certain changes in vegetation and soils result in irreversibly degraded rangeland ecosystems. We used Advanced Very High Resolution Radiometer (AVHRR) imagery to develop calibration patterns of change in the Normalized Difference Vegetation Index (NDVI) over the growing season for selected sites for which we had ground data and historical data characterizing these sites as irreversibly degraded. We used the NDVI curves for these training sites to classify and map the irreversibly degraded rangelands in southern New Mexico. We composited images into four year blocks: 1988–1991, 1989–1992, and 1990–1993. The overlap in pixels classified as irreversibly degraded ranged from 42.6% to 84.3% in year block comparisons. Quantitative data on vegetation composition and cover were collected at 13 sites within a small portion of the study area. Wide coverage reconnaissance of boundaries between vegetation types was also conducted for comparisons with year block maps. The year block 1988–1991 provided the most accurate delineation of degraded areas. The rangelands of southern New Mexico experienced above average precipitation from 1990–1993. The above average precipitation resulted in spatially variable productivity of ephemeral weedy plants on the training sites and degraded rangelands which resulted in much smaller areas classified as irreversibly degraded. We selected imagery for a single year, 1989, which was characterized by the absence of spring annual plant production in order to eliminate the confounding effect of reflectance from annual weeds. That image analysis classified more than 20% of the rangelands as irreversibly degraded because areas with shrub-grass mosaic were included in the degraded classification. The single year image included more than double the area classified as irreversibly degraded by the year blocks. AVHRR imagery can be used to make triage assessments of irreversibly degraded rangeland but such assessment requires understanding productivity patterns and variability across the landscapes of the region and careful selection of the years from which imagery is chosen. 相似文献
730.
Anthony R. Olsen Joseph Sedransk Don Edwards Carol A. Gotway Walter Liggett Stephen Rathbun Kenneth H. Reckhow Linda J. Yyoung 《Environmental monitoring and assessment》1999,54(1):1-45
The United States funds a number of national monitoring programs to measure the status and trends of ecological and natural resources. Each of these programs has a unique focus; the scientific objectives are different as are the sample designs. However, individuals and committees, all well aware of the cost of ecological monitoring, have called for more effective monitoring programs. The objective of this paper is to summarize existing programs' statistical designs and discuss potential alternatives for improvement in national monitoring. Can we improve the current situation by providing an overall framework for the design or analysis of data from these disparate surveys? First, the paper summarizes the objectives of these surveys, compares and contrasts their survey designs as currently implemented, and determines what variables they collect. Through this process we identify commonalities and issues that impact our ability to combine information across one or more of the surveys. Three potential alternatives are presented, leading to comprehensive monitoring in the United States. 相似文献