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981.
Jeroen van Rooijen 《Journal of Agricultural and Environmental Ethics》1989,2(3):235-240
Knowledge of the backgrounds of students of behaviour working in the field of applied animal behavior science may help us to recognize their influence on conclusions reached in a particular study and on more general points of view. This recognition may result in a speed up of the progress in this science, to the benefit of science and animals. Some types are: (1) Eco-ethologists (ethologists of the hunters-type). They like to stalk healthy wild animals in their natural environment. They are less interested in the abnormal behavior of domestic animals under husbandry circumstances. (2) Behaviorists. These are psychologists that still think in a man-animal dichotomy. They are not interested in animals for their own sake but as models for human behavior. (3) Behavior physiologists. These biologists are not primarily interested in behavior. Because of the type of experiments they perform they have an aversity against animal protectionists. (4) Ethologists of the farmers type. These ethologists want to posses animals, collect animal species, take care of them and breed them. They are able to speak on approximately the same wavelength as farmers as well as animal protectionists. (5) Zootechnicians of the farmers type. These scientists want to make a living out of animals and like to take care for them. They are also able to speak at approximately the same wavelength as farmers and animal protectionists. 相似文献
982.
The recycling sector in India, which consists of a comprehensive trade and production sector, is rather complex. Nevertheless, it creates important benefits for both the economy and the environment. In order to comprehend the system, a case study has been performed on the recycling sector (paper, plastic, glass and non-ferrous metal) in Bangalore (India), focussing on the market structure, the scale of operation, employment effects, constraints, and recent developments. It was found that this highly competitive and labour-intensive industry is largely dependent on cheap labour and the supply of solid waste from the local trade system. Its mostly informal nature results from the ‘unregisteredness’ of the materials. Consequently, government involvement is avoided as much as possible. With present growth rates, prospects of recycling in Bangalore are advancing. Yet, problems such as lack of supply and loss of quality emerge. Therefore, quality control and market conditions should be improved. 相似文献
983.
Pascal de Decker Erwin Lammens Paul van der Sluys Leopold van der Vliet Peter J. Van Severen 《Journal of Environmental Planning and Management》1987,30(2):91-98
This article deals with Flanders’ urbanity. At the moment Flanders, a part of Belgium, is responsible for its own town and country planning. Nevertheless, today's picture of urbanity is, for the greatest part, the result of Belgian policy. The results are nothing to be proud of. In fact Flanders has no urbanity anymore, nor a real rurality. Everywhere in the countryside there are houses and other constructions; on the other hand and consequently the centres of cities and villages are in decay. The following text tries to draw, very briefly, the problems and the development of the problems in urban and rural Flanders. The roots have to be searched in the 19th century, especially in the constitution of Belgium, which is one of the most liberal on earth. The first part of the article is dealing with the history of urbanisation, whilst the second part deals with some recent evolutions in housing and housing policy, in employment and employment policy, in transport and transport policy. Finally, the third part is concerned with the town and country planning which has to structure the developments in spatial use for housing, industrial building and so on, but which has failed. 相似文献
984.
This paper discusses the major developments in regional policy in the Netherlands by relating the policy instruments and locations to stages in the socio‐economic and political development of the Netherlands from 1945 onwards. It concludes that, at present, the spatial dimension of economic policy has lost importance, and the support for peripheral regions is restricted. 相似文献
985.
Theoretically, a resource rent tax is neutral in that it does not influence the allocation of resources. However, the application of such fundamental principles in the tax formula of the South African gold mining industry negates the neutrality principle. A progressive element in the tax rate encourages mining of submarginal ores - leads to misallocation of resources. However, it substantially reduces the financial risks of a mining company engaged in the extraction of a commodity characterized by price volability, such as gold, and permits economies of scale in mining and encourages conservation of a non-renewable resource. As long as prices increase faster than costs, the advantages of this system probably exceed the disadvantages. The choice of the threshold rate in such a tax system is critical. If it is too high it will encourage mining of submarginal ores, and if too low it does not recognize the peculiar risks of gold mining investments. 相似文献
986.
Marcel van der Perk Philip N. Owens Lynda K. Deeks Barry G. Rawlins 《Water, Air, & Soil Pollution: Focus》2006,6(5-6):443-451
A spatially extensive geochemical data set of stream water and bed sediment composition across the Tamar catchment in south-west
England was analysed to identify the key bed sediment properties that control the in-stream dissolved reactive phosphorus
(DRP) concentrations during baseflow conditions. Linear regression analysis of the streamwater DRP concentrations and the
distribution coefficient K
d for DRP revealed that the former is positively correlated with total SiO2 and Al2O3, and negatively correlated with K2O. The primary control on these major element distributions is the dominant bedrock geology. The data suggest that streamwater
DRP concentrations are mainly controlled by adsorption to clay minerals. Where P concentrations in streamwater were considerably
elevated by inputs from point sources, DRP concentrations are also controlled by precipitation of hydroxyapatite. 相似文献
987.
The combined XAD-4/8-Ames test procedure for concentrating and detecting trace amounts of organic mutagens, as already described for surface water, is shown to be suitable for drinking water as well. DMSO is as effective as acetone in eluting the adsorbed mutagens, and optimal recovery of overall mutagenic activity is observed at a flow rate of 2–4 bed volumes/min. The drinking water of 6 cities in The Netherlands, which prepare their drinking water from the rivers Rhine and Meuse, has been tested for mutagenic activity. Mutagenic activity could be demonstrated in 4 cities. Dose-related responses are observed with concentrates of as little as 500 ml of drinking water and the 4 cities clearly differ with regard to the type of mutations induced (TA 98 or TA 100) and the effect of metabolic activation. The absence of mutagenic activity in drinking water of 2 cities indicates that by a proper combination of treatment processes the organics which are responsible for the detected mutagenic activity in drinking water can be removed to a high degree. 相似文献
988.
989.
Betti M Aldave de las Heras L Janssens A Henrich E Hunter G Gerchikov M Dutton M van Weers AW Nielsen S Simmonds J Bexon A Sazykina T;European Commission Marina II study 《Journal of environmental radioactivity》2004,74(1-3):255-277
Enhanced levels of naturally occurring radioactive materials (NORM) are produced through various industrial operations and may lead to discharges to the marine environment. A recent study, called MARINA II, carried out for the European Commission considered discharges of radionuclides from the NORM industries to north European marine waters and their consequences. There are two main sources that were considered in the study. The use of phosphogypsum during the production of phosphoric acid by the fertiliser industry and the pumping of oil and gas from the continental shelf in the North Sea which produces large quantities of water contaminated with enhanced levels of naturally occurring radionuclides. Discharges of alpha emitting radionuclides from these two industries have contributed significantly to the total input of alpha emitters to north European waters over the period 1981-2000 (data were not available prior to 1981). Discharges due to the use of phosphogypsum have declined since the early 1990s and are now very low. Discharges from the oil and gas industries stabilised in the second half of the 1990s and are now the major contributor to alpha discharges to the region. As most European countries do not report discharges of radioactivity with the water produced during extraction, there is considerable uncertainty in the discharges used in the study. The impact of the discharges has been estimated both in terms of the effect on non-human biota and the radiological impact for people. In the 1980s the radiation dose rates to marine biota in the region around a phosphate plant on the north-west coast of England were as high due to the discharges from the phosphate plant as those near to the Sellafield reprocessing plant due to its discharges. In recent years the additional dose to marine biota in this region due to the past NORM discharges is of the same order of magnitude as the natural background. The collective dose rate was estimated to determine the radiological impact on people. The peak collective dose rate from the NORM industries occurred in 1984 and was just over 600 manSv y(-1). The collective dose rate fell with time as discharges from the phosphate industry reduced and was estimated as under 200 manSv y(-1) in 2000. 相似文献
990.
van Put P Debauche A De Lellis C Adam V 《Journal of environmental radioactivity》2004,72(1-2):177-186
Following the recognition of their usefulness by the authorities and the scientific community, automatic water monitoring networks were developed again to be able to measure seawater. For that purpose, they had to be fully autonomous, with low power consumption (solar panel power supply), wireless communicating (satellite, GSM, radio) and very sensitive (a few Bq/m3). 相似文献