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91.
The premise of this article is that the planning and design of new rest camps in conservation areas should be based on ecological
principles in such a way that the plant ecology within the camp be an integral part and extension of the natural ecology of
its immediate vicinity. This is desirable so that visitors to the camp will be provided not only with facilities for resting,
eating, and sleeping, but also be able to enjoy and study the natural environment in a relaxed atmosphere. The Berg-en-Dal
rest camp, which was established in Kruger National Park, was planned in such a way and designed according to the principles
outlined by the authors in a companion article.
The planning included six zones: a control zone, day visitor zone, overnight visitor zone, staff accommodation zone, recreation
zone, and service zone. The point is stressed that plant species selected to be used as additional vegetation to those already
growing in the camp were endemic to the nine landscape facets identified in the camp. The design allowed for separation of
the various land-use zones in such a way that they would complement each other rather than be a hindrance to each other. The
camp has been built according to the plans included in this article and has proved to be a great success. The conclusion is
drawn that the planning principles are sound and should be used in the future for the planning and design of rest camps for
conservation areas in South Africa. 相似文献
92.
A four-stage method of providing conditions for improving the stability of a landscape sector is presented. In the first stage,
structure and function of the landscape system is examined, predominantly based on the results of monitoring. In the second
stage, a method is suggested for applying monitoring data to a dynamic structure with complex functions of the territory under
examination. In the third stage, the territory is optimized as to the function of particular components within it. The optimization
consists in controlling the dynamics of the flows of material, energy, and population within the sector. In the fourth stage,
the holistic function of the landscape strip should be monitored with respect to representative key factors. The entire concept
is based on assuming the existence of destabilizing processes leading to ecocritical situations and determining mitigating
factors using heuristic methods of optimization. 相似文献
93.
Four broad classes of dependent variables (psychological strain, physical illness symptoms, health-related behaviour and social participation) were associated with eleven categories of stressors and stress moderators from work and family life, using multiple logistic regression analysis for a random sample of 8700 full-time male and female members of T.C.O., a major Swedish white-collar labour federation (covering 25 per cent of the Swedish labour force). Our goal was to find broad patterns of associations by comparing relative magnitudes of effects for (a) stressors and stress moderators; (b) work and family activities, and (c) males and females. Fifty per cent of the associations between environmental factors and dependent variables were significant in the predicted direction at the 5 per cent level. However, only 5 per cent of the associations are as strong, for example, as average smoking/heart disease associations. Our primary conclusion is that job factors are the next strongest set of predictors of health and behaviour after age. Job factors are stronger than family factors for both men and women; proportionally increasing the explained variance by over 60 per cent versus roughly 20 per cent for family factors (over the 25 per cent of explanation due to demographic factors). The overall pattern of stressor/outcome associations is quite similar for men and women, although both job/outcome and family burden/outcome associations are stronger for women than for men. We failed to find a clear linkage between particular stressors and particular physical illnesses. Among the job factors, control and work load have the strongest associations; with the former predicting behaviour patterns and job satisfaction (along with social support), and the latter predicting mental strain symptoms. Family problems are associated with increased health risks (stronger for men) and family responsibilities and constraints affect health behaviour (stronger for women). Job satisfaction is the most successfully predicted outcome in the study, and is similarly affected for men and women. 相似文献
94.
M. van der Zee J. H. Stoutjesdijk P. A. A. W. van der Heijden D. de Wit 《Journal of Polymers and the Environment》1995,3(4):235-242
The biodegradability of oxidized starch and inulin has been studied in relation to the degree of periodate oxidation to dialdehyde derivatives, by measuring oxygen consumption and mineralization to carbon dioxide. A higher degree of oxidation of dialdehyde starch and dialdchyde inulin results in a lower rate at which the polymers are biodegraded. It is demonstrated that the biodegradation rate of dialdehyde inulin derivatives decreases more than that of equivalent starch derivatives. The differences in biodegradation behavior between dialdehyde starch and dialdehyde inulin, resulting from comparable modifications, are discussed in terms of conformational structure. 相似文献
95.
Jan Narveson 《Journal of Agricultural and Environmental Ethics》1995,8(2):145-156
Environmental Ethics is the ethics of how we humans are to relate to each other about the environment we live in. The best way to adjust inevitable differences among us in this respect is by private property. Each person takes the best care of what he owns, and ownership entails the free market, which enables people to make mutually advantageous trades with those who might use it even better. Public regulation, by contrast, becomes management in the interests of the regulators, or of special interests, such as lovers of rare species-not the people they're supposed to be serving. 相似文献
96.
Integrated economic-ecological analysis and evaluation of management strategies on nutrient abatement in the Rhine basin 总被引:1,自引:0,他引:1
Management of river basins involves the making of informed choices about the desired levels of economic activities and ecosystem functioning in the catchment. Information on the economic and ecological effects of measures as well as their spatial distribution is therefore needed. This paper proposes the following instruments to support decision-making in river basins: (1) the linking of models and indicators to describe the economic and ecological effects of management actions and their spatial distribution and (2) an extended evaluation framework that aims to evaluate management actions on three objectives for sustainable river management. These are cost-effectiveness, spatial equity, and environmental quality. This paper illustrates the potential of these instruments for river basin management by a case-study on nutrient management in the Rhine basin. In this case-study four nutrient abatement strategies are formulated, based on policies of the International Commission for the Protection of the Rhine and the North Sea Commission. These strategies are analysed and evaluated on their contribution to the three management objectives. Results show that none of these strategies score highest on cost-effectiveness, spatial equity and environmental quality simultaneously. It appears that cost-effectiveness is in conflict with environmental quality, whereas spatial equity and cost-effectiveness show quite close correspondence. This means that a trade-off has to be made between costs and spatial equity on the one hand, and environmental standards on the other hand. This paper offers a framework to make these trade-offs more explicit and provides quantitative information on cause-effect relationships, economic and environmental effects and the spatial distribution of these effects for various management strategies. This information can be particularly useful in the development of compromises required to establish international agreement and co-operation. 相似文献
97.
Cor van der Weele 《Journal of Agricultural and Environmental Ethics》2006,19(3):313-324
Official Dutch food information apparently tries to avoid images but is implicitly shaped by the metaphor that food is fuel.
The image of food as fuel and its accompanying view of the body as a machine are not maximally helpful for integrating two
important human desires: health and pleasure. At the basis of the split between health and pleasure is the traditional mind–body
dichotomy, in which the body is an important source of evil and bodily pleasure is sinful and dangerous. In the search for
alternatives, new metaphors are proposed that integrate mind and body as well as pleasure and health. The relevance of metaphors
for ethics is at least twofold. (1) Moral thought and theory are at least partly shaped by metaphors. In the light of this
growing recognition, the analysis of morality needs innovation. (2) With regard to food, new metaphors, such as slow food,
or the image of enjoyment as an art, enable a new search for morally responsible forms of hedonism, based on more love and
respect for human as well as animal bodies. But new metaphors are specific and selective, just like old ones. I argue that
a search for the best overall metaphor would be misguided, but that more diverse forms of attention to bodily aspects of life,
including experiences related to food, will result in richer vocabularies of the body, the mind, and body–mind relations.
This holds a promise of moral progress. 相似文献
98.
Joie C. Taylor Nick van de Giesen Tammo S. Steenhuis 《Journal of the American Water Resources Association》2006,42(4):1113-1126
ABSTRACT: Water resource management in West Africa is often a complicated process due to inadequate resources, climatic extremes, and insufficient hydrological information. Insufficient data hinder sustainable watershed management practices, one of the top priorities in the Volta River Basin. This research properly fills in missing data by modeling the hydrological distribution in the Volta River Basin. On average, discharge gages across the basin are missing 20 percent of their monthly data over 20 years. Two methods were used to supplement missing data: a statistically linear model and a conceptual hydrological model. A linear equation, developed from the regression of precipitation and runoff, was used to evaluate the quality of existing data. The hydrological model separates the system into root and groundwater zones. Measured values were used to calibrate the hydrological model and to validate the statistical model. The quality of existing data was analyzed and organized for usability. Accuracy of the hydrological model was also evaluated for its effectiveness using R2 and standard error. It was found that the hydrological model was an improvement from the linear model on a monthly basis; R2 values improved by as much as 0.5 and monthly error decreased. Monthly predictions of the hydrological model were used to fill gaps of measured data sets. 相似文献
99.
Jan Cademartori 《Natural resources forum》2002,26(1):27-44
The desert mining region of Antofagasta, Chile, enjoyed spectacular economic growth in the 1990s as a result of foreign direct investment (FDI), mainly in the exploitation of the region's rich copper deposits. In a country considered by international financial institutions to be a good example of economic performance, Antofagasta has been termed a model region,and Chile's economic and social development in the 1990s has been considered a suitable model for other Latin American countries. However, development indices based on statistical data must be examined with caution, as human welfare does not necessarily keep pace with economic growth. This article analyses the Antofagasta Region in terms of problems that may occur in conjunction with accelerated economic growth, and how these can affect the environment, as well as the regional labour market. The article also examines a regional economic strategy for Antofagasta recently proposed by the local government, and suggests new alternatives for the sustainable economic development of the region. 相似文献
100.
Anthony L. Andrady Jan E. Pegram Shuji Nakatsuka 《Journal of Polymers and the Environment》1993,1(1):31-43
Studies on three types of enhanced photodegradable polyethylenes showed tensile elongation at break to be a suitable parameter for assessing disintegration due to outdoor weathering. Disintegration rates varied greatly with exposure location, with Arizona the harshest environment and Washington and New Jersey the mildest. The rate of breakdown of the enhanced degradable polyethylenes relative to unmodified plastic was termed an enhancement factor. For the materials studied, average enhancement factors generally ranged from five to fifteen. The location-dependent variability in rate parameters can be mostly explained in terms of different average radiation levels and temperatures at these locations. A duplicate exposure protocol was developed to determine if the test data were complicated by short-term fluctuations in sunlight or temperature during exposure. 相似文献