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1.
The traveling salesman's problem, in which one decides which order between n locations minimizes total travel distance, was used as a laboratory analogue of spatial decisions in large-scale environments. In an experiment in which university students were observed while solving this problem, a group who received numerical information about distances between locations was found to minimize local distances rather than total distance, that is, to choose first the closest location from the starting location, then the closest location from that chosen, and so forth. However, if a picture of the locations was presented, total distance was minimized more frequently than local distances, presumably because subjects changed their decisions which minimized local distances when they discovered spatial patterns indicating that a shorter path existed. It was also found that a picture did not always have to be presented because subjects mentally constructed a functionally equivalent spatial representation from pieces of direction and distance or only direction information. This finding was even clearer when subjects were allowed to draw pictures of the locations.  相似文献   

2.
It has traditionally been accepted that people structure their cognitive map of the city through the five Lynch categories: path, edge, district, node and landmark. This study confirms empirically the existence of these categories in two different experiments applying two forms of multivariate analysis: hierarchical cluster analysis and correspondence analysis based on Euclidean and χ2 distances, respectively. The problematic edge category is also discussed, as well as the influence of centre-periphery dimensions on these categories.  相似文献   

3.
Two experiments examined whether differences in elevation of the terrain are encoded in cognitive maps of outdoor environments. In Experiment 1, two groups of subjects who had travelled a varying number of times between a set of locations made direct estimates in metres of the differences in elevation between the locations. The results showed that subjects in both groups had knowledge of elevation but those for whom the terrain was less familiar tended to exaggerate the differences. In Experiment 2, decision times were measured of responses to the question whether one location is below or above another one. Neither for subjects who were more, nor for subjects who were less familiar with the terrain, did the decision times vary with the distances between the locations, thus failing to support the hypothesis that differences in elevation are retrieved by a process of ‘mental travel’.  相似文献   

4.
Since the Earth Summit in Rio, declining biodiversity has become a subject of general concern for many countries. To counter these negative trends, government nature policies in Europe at least are now thought out primarily in terms of networks. They concern new areas outside nature reserves, new players and new management strategies. Consequently, these policies should themselves become the subject of new public debate. Our study concerns the analysis of the forms used to collect the data required to set up the European Union's Natura 2000 network and maps drawn as part of the Council of Europe's Pan-European Ecological Network strategy. The aim of this article, which takes the perspective developed by the sociology of science, will be to show how the forms and maps used in these new nature policies produce knowledge that precedes policy discussions to search for the best possible socio-political compromises. In other words, the knowledge that is collected in and by means of these documents, forms and maps offers a cognitive way of ‘framing’ the subsequent public debates. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

5.
This study investigated the hypothesis that there is a sex difference in the extent of children's home ranges and therefore a corresponding difference in their home area cognitive maps. Cognitive maps were elicited using a road construction kit and the resulting maps scored for embedding, extent and detail. Home ranges were investigated using a photographic recognition test and by children indicating home range extent on aerial photographs. The results supported the hypothesis of a sex difference. However, these sex-related mapping differences disappeared when children were required to create maps of areas to which both sexes had limited and controlled exposure. Thus, the original sex-related differences appear to be associated with differences in the size of familiar territory rather than with any male superiority in spatial cognition or map-building ability. The latter was shown to be related to general intelligence as reflected by scores on Raven's Progressive Matrices.  相似文献   

6.
Small-holder farmers often develop adaptable agroforestry management techniques to improve and diversify crop production. In the cocoa growing region of Ghana, local knowledge on such farm management holds a noteworthy role in the overall farm development. The documentation and analysis of such knowledge use in cocoa agroforests may afford an applicable framework to determine mechanisms driving farmer preference and indicators in farm management. This study employed 12 in-depth farmer interviews regarding variables in farm management as a unit of analysis and utilized cognitive mapping as a qualitative method of analysis. Our objectives were (1) to illustrate and describe agroforestry management variables and associated farm practices, (2) to determine the scope of decision making of individual farmers, and (3) to investigate the suitability of cognitive mapping as a tool for assessing local knowledge use. Results from the cognitive maps revealed an average of 16 ± 3 variables and 19 ± 3 links between management variables in the farmer cognitive maps. Farmer use of advantageous ecological processes was highly central to farm management (48% of all variables), particularly manipulation of organic matter, shade and food crop establishment, and maintenance of a tree stratum as the most common, highly linked variables. Over 85% of variables included bidirectional arrows, interpreted as farm management practices dominated by controllable factors, insofar as farmers indicated an ability to alter most farm characteristics. Local knowledge use on cocoa production revealed detailed indicators for site evaluation, thus affecting farm preparation and management. Our findings suggest that amid multisourced information under conditions of uncertainty, strategies for adaptable agroforestry management should integrate existing and localized management frameworks and that cognitive mapping provides a tool-based approach to advance such a management support system.  相似文献   

7.
Available estimates of potentially recoverable world mineral and fuel resources are examined with a view to determining whether everyone likely to be living on earth next century could be raised to the material living standards people in developed countries now have. It is concluded that this goal is impossible. A number of fundamentally important implications follow, especially regarding the inappropriateness of growth strategies in general, goals for Third World development, and the need for ‘de-development’ of developed countries to much more frugal, self-sufficient and cooperative social systems.  相似文献   

8.
Although for a long time environmental psychologists have been concerned with the nature and process of environmental perception and its representation in map forms, global sketch maps have not been popular in mainstream research. Further, conceptual and theoretical insights into the subject are yet to be fully achieved; and quite significantly, comparative analysis has been limited by the concentration of research efforts in the developed countries of Europe and America. In the same vein, the challenge of clarifying the psychological, spatial and social underpinnings of cognitive maps and their contributory role in day-to-day space-related problem solving and decision-making brings to the fore the need for cross-disciplinary and across-regional studies. This paper examines the world's image from an African perspective, exploring those countries of the world that are best known to Africans and the factors responsible for the pattern of recall and representation in the maps drawn by them. Some 656 maps were collected from 13 sites in 11 countries. Analysis of the frequency of inclusion of countries was first carried out; chi-square analysis was then performed on the frequency of inclusion by level of a country's economic development, population, geographical size and relative location from Nigeria and Africa. The results from qualitative interpretation show that while images of countries may have been influenced by composite and multifaceted factors, embracing historical and cultural associations, media images and invocations, Africans, nevertheless, tended to recall nations following some descending hierarchy, with ‘developed/geographically prominent countries’, ‘we’ (i.e. Africa), ‘others’ and ‘unknown’ countries as discernible clusters. From statistical test, population and spatial size of countries, the proximity of countries to the assessors and to some extent, level of economic development, were found to be significant in accounting for the pattern of recall and representation in cognitive maps. The paper shows that in spite of the evident limitations of mental sketches they hold some promise for our understanding of cross-regional variations in the images of the world, which could be important to the building of relevant social and geographical education to foster global understanding.  相似文献   

9.
European Union agri-environmental schemes aim to reduce the environmental impact of agricultural production, but were developed before consideration of greenhouse gas emissions from agriculture. Life cycle assessment methodology provided a framework for comparing emissions as kg CO2 equivalent per kg of energy corrected milk (ECM) (kg CO2 kg(-1) ECM yr(-1)) and per hectare (kg CO2 ha(-1) yr(-1)) for farms both within and outside the Irish agri-environmental scheme. The agri-environmental scheme farms operate extensive systems from 40 to 120 cows producing between 3032 and 5946 kg ECM cow(-1) lactation(-1). The cows are fed on grass, conserved silage, and concentrates. Supplementation ranged between 250 and 620 kg cow(-1) yr(-1). The conventional farms had between 30 and 77 milking cows producing 4736 to 6944 kg ECM cow(-1) lactation(-1). Supplementation ranged from 400 to 1000 kg cow(-1) yr(-1). The emissions from each unit were estimated using published emissions factors and possible error was evaluated by using ranges for each factor. Calculated emissions ranged from 0.92 to 1.51 kg CO2 kg(-1) ECM yr(-1) and 5924 to 8323 kg CO2 ha(-1). On average, total emissions from conventional farms were around 18% (p = 0.01) greater than the agri-environmental scheme farms and emissions per hectare (total area required) were 17% greater (p = 0.02) but there was no significant difference (p = 0.335) in terms of emission per unit milk produced. To evaluate greenhouse gas emissions for each farm in terms of the system intensity it was necessary to define a measure of intensification and area per liter of milk produced that was best.  相似文献   

10.
The biological health of soil is an important aspect of soil quality because of the many critical functions performed by organisms in soil. Various indicators of soil quality have been proposed, but measurements of microbial biomass are most commonly used. During decomposition of plant residues in soil the relative intensities of the O-alkyl-C signal decreases and the alkyl-C signal increases in nuclear magnetic resonance (NMR) spectra. This leads to the suggestion that the alkyl-C to O-alkyl-C ratio of a soil may indicate the degree of decomposition. Consequently, the overall resource quality of soil C as a substrate for heterotrophic microorganisms may be inversely related to the alkyl-C to O-alkyl-C ratio. Our hypothesis is that a relationship exists between the size of the soil microbial community (microbial biomass) and the quality of soil carbon as a resource for microorganisms. New data have been combined with previously published data to show that there was a significant, negative correlation between the biomass C to total C (Cmic, to Corg) ratio and the alkyl-C to O-alkyl-C ratio (p < 0.01), which supports our hypothesis.  相似文献   

11.
The results of this study indicate that manipulations of the pathway grid configuration and landmark placement in a setting cause changes in environmental knowledge. These experimental manipulations were accomplished using a realistic, dynamic simulation technique at the Berkeley Environmental Simulation Laboratory. Measures of environmental knowledge include: memory for incidental information along the simulated urban route, accuracy of route maps, relocation memory for scenes along the route, and questionnaire measures. Data are also presented showing both positive and negative effects of stress from noise on the processes of environmental cognition.  相似文献   

12.
While the People's Republic of China appears on a daily basis in all of the important newspapers around the world with its enormous successes in modernizing its economy, life in the Chinese countryside usually does not attract international attention. However, we know from a wide range of reports that the situation in the Chinese countryside is getting more and more complicated with local corruption, pollution and poverty growing in most parts of the country. The Chinese language press reports on a growing number of local uprisings in remote areas. While some analysts regard the situation in the countryside as a potential threat to the ongoing peaceful process of economic reform in China, China seems to be well prepared to cope with this change and the state is comparatively flexible in dealing with unrest among the rural population. So far the system itself has not been challenged by peasant discontent. This article introduces the idea that the distance between state and rural society is the basis of this flexibility. It will analyze a major policy document issued by the state and party leadership in order to show how state and rural society interact on the basis of a still insurmountable distance between state and rural society.  相似文献   

13.
Research on environmental activism remains poorly integrated and ill-defined and to date, there has been little examination of the relationship of environmental activism, pro-environmental behaviour and social identity. 131 students from an Australian University (M = 25.04 years old, SD = 8.17) voluntarily participated by returning an anonymous questionnaire containing an environmental activism scale, a pro-environmental behaviour scale and a social identity scale. The results revealed that while there was a significant relationship between social identity and environmental behaviour, only the citizenship component of environmental behaviour significantly predicted environmental activism. In other words, the relationship between social identity and environmental activism was indirect. This research presents the opportunity for further exploration of these relationships and to further investigate their relationship to inter-group processes.  相似文献   

14.
This pilot study proposes a social map-making method based on the link between the evaluation of the neighbourhoods and the populations residing in them. It was carried on a sample of residents of Dijon’s urban area, a French city (N = 99) divided into four groups, according to the geographical location (in the city / in the suburbs) and the social status (wealthy / disadvantaged) of their living space. The procedure is inspired by social representation gathering methods. Respondents were asked (1) to evaluate their own neighbourhood and others on two scales (social reputation and personal appreciation); (2) to evaluate populations on two similar scales; (3) to determine how these populations are spared in the different neighbourhoods. The central hypothesis of this study was that evaluations of a sector would be linked to the populations living there in the representation of the individuals. Results showed that the correlation between the evaluation of a sector and the perceived proportion of French in this sector with a good reputation is strong and positive. The method has also showed patterns of repartition in the representations of the inhabitants: while certain populations are concentrated in precise sectors, others are scattered across the territory.  相似文献   

15.
Fuzzy cognitive mapping was used to develop a participatory ecosystem management plan for Uluabat Lake, Turkey. Interviews were conducted with stakeholders belonging to six different groups. Lake pollution was the most central and most mentioned variable for stakeholders. Stakeholder groups agree that lake pollution is negatively affecting ecosystem health and thereby local economies. Thus, reducing lake pollution was chosen as the overall goal for the management plan. Possible ways to reduce lake pollution and increase ecosystem health were seen differently by the different groups. Hunters, factory managers, NGO personnel, and local people thought industry was the main cause of lake pollution, while officials from the government and local municipalities thought roads and urban development contributed the most to lake pollution. Generally the stakeholder groups did not perceive their own actions as affecting the lake as strongly as other groups thought. For example, factory managers viewed factory pollution as negatively affecting the lake but less strongly than the other groups did. According to policy option simulations, reducing lake pollution had positive effects on all variables, especially fish, birds, animal husbandry, irrigation, agriculture, and the ecological balance of the lake. Results of this analysis were used to facilitate meetings among stakeholder groups and to develop a participatory ecosystem management plan. The analysis was useful for pointing out the similarities as well as the differences among the groups. It also helped the facilitators understand the focus of each stakeholder group and enabled them to suggest activities in which each group would want to participate.  相似文献   

16.
This paper examines the relationship between quality of life indicators and the gross value of minerals production from Australian regions. We used quality of life indicators, aggregated for 71 local government areas containing mining activities, of household income, housing affordability, access to communication services, educational attainment, life expectancy, and unemployment. We find no evidence of systematic negative associations between quality of life and the gross value of minerals production. Instead, mining activity has a positive impact on incomes, housing affordability, communication access, education and employment across regional and remote Australia. Whilst we do not establish causality between mining activity and quality of life, our analysis prompts a rethink of the resource curse as it applies within a single country. We did not find evidence of a resource curse, at the local government level, in Australia’s mining regions. Nevertheless, we note observations by many other researchers of negative social impacts on specific demographic sectors, localities, families of fly-in fly-out mining operations, and individuals. This contrast may be a scale issue, with the regional benefits of mineral wealth masking highly localised inequalities and disadvantage. We suggest that there is a need to better understand these impacts and, more importantly, the types of policy mechanisms government and industry can adopt to mitigate or avoid them.  相似文献   

17.
Spatial scaling between leaf area index maps of different resolutions   总被引:1,自引:0,他引:1  
We developed algorithms for spatial scaling of leaf area index (LAI) using sub-pixel information. The study area is located near Liping County, Guizhou Province, in China. Methods for LAI spatial scaling were investigated on LAI images with 960 m resolution derived in two ways. LAI from distributed calculation (LAID) was derived using Landsat ETM+ data (30 m), and LAI from lumped calculation (LAIL) was obtained from the coarse (960 m) resolution data derived through resampling the ETM+ data. We found that lumped calculations can be considerably biased compared to the distributed (ETM+) case, suggesting that global and regional LAI maps can be biased if surface heterogeneity within the mapping resolution is ignored. Based on these results, we developed algorithms for removing the biases in lumped LAI maps using sub-pixel land cover-type information, and applied these to correct one coarse resolution LAI product which greatly improved its accuracy.  相似文献   

18.
This paper analyses the role of exploration as an uncertainty-reducing activity for a company facing resource taxation. Such exploration is of benefit, even to a risk-neutral company, because it enables a better decision to be made regarding extraction investment (Kretzer, 1994). This paper extends previous contributions to the economics of exploration in several areas which are of practical significance. First, exploration is analysed both in the context of a log-normally distributed resource deposit and of an ad valorem royalty. Second, the role of exploration in an ad valorem royalty regime is contrasted with that of a Resource Rent Tax. Finally, the relationship between exploration and resource taxation in situations of very divergent pre-exploration levels of uncertainty is considered.  相似文献   

19.
Modeling the relationship between land use and surface water quality   总被引:64,自引:0,他引:64  
It is widely known that watershed hydrology is dependent on many factors, including land use, climate, and soil conditions. But the relative impacts of different types of land use on the surface water are yet to be ascertained and quantified. This research attempted to use a comprehensive approach to examine the hydrologic effects of land use at both a regional and a local scale. Statistical and spatial analyses were employed to examine the statistical and spatial relationships of land use and the flow and water quality in receiving waters on a regional scale in the State of Ohio. Besides, a widely accepted watershed-based water quality assessment tool, the Better Assessment Science Integrating Point and Nonpoint Sources (BASINS), was adopted to model the plausible effects of land use on water quality in a local watershed in the East Fork Little Miami River Basin. The results from the statistical analyses revealed that there was a significant relationship between land use and in-stream water quality, especially for nitrogen, phosphorus and Fecal coliform. The geographic information systems (GIS) spatial analyses identified the watersheds that have high levels of contaminants and percentages of agricultural and urban lands. Furthermore, the hydrologic and water quality modeling showed that agricultural and impervious urban lands produced a much higher level of nitrogen and phosphorus than other land surfaces. From this research, it seems that the approach adopted in this study is comprehensive, covering both the regional and local scales. It also reveals that BASINS is a very useful and reliable tool, capable of characterizing the flow and water quality conditions for the study area under different watershed scales. With little modification, these models should be able to adapt to other watersheds or to simulate other contaminants. They also can be used to study the plausible impacts of global environmental change. In addition, the information on the hydrologic effects of land use is very useful. It can provide guidelines not only for resource managers in restoring our aquatic ecosystems, but also for local planners in devising viable and ecologically-sound watershed development plans, as well as for policy makers in evaluating alternate land management decisions.  相似文献   

20.
As the scope and scale of New Zealand (NZ) dairy farming increases, farmers and the industry are being challenged by Government and the New Zealand public to address growing environmental concerns. Dairying has come under increasing scrutiny from local authorities tasked with sustainable resource management. Despite recent efforts of farmers and industry to improve resource use efficiency, there is increasing likelihood of further regulatory constraints on water use and nutrient management. This study uses available data on farm-gate nitrogen (N) surpluses and milk production from the Waikato, New Zealand's largest dairying region, together with a farm scale modeling exercise, to provide a perspective on the current situation compared to dairy farms in Europe. It also aims to provide relevant guidelines for N surpluses and efficiencies under NZ conditions. Waikato dairy farms compare favorably with farms in Europe in terms of N use efficiency expressed as L milk/kg farm-gate N surplus. Achievable and realistic good practice objectives for Waikato dairy farmers could be 15,000 L milk/ha (1200 kg milk fat plus protein/ha) with a farm-gate N surplus of 100 kg/ha giving an eco-efficiency (L milk/kg N surplus) of 150, and long-term average nitrate leaching losses of approximately 25-30 kg/ha/yr. This can be achieved by increasing the N conversion efficiency through lower replacement rates (16 versus 22%), lower stocked (< 3 cows/ha) high genetic merit cows (30 L milk/day at peak) milked for longer (277 versus 240 days), feeding effluent-irrigated, home-grown, low-protein supplements to cows on high-protein, grass-clover pastures to dilute N concentration in the diet, removing some of the urinary N from the paddocks during critical times by standing cows on a loafing pad for part of the day, and through lower N fertilizer rates (50-70 kg/ha/yr compared to the norm of 170-200 kg/ha/yr) and using a nitrification inhibitor and gibberellins to boost pasture growth and the former to reduce N leaching.  相似文献   

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