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1.
Quadratic programming techniques were applied to household food consumption data in England and Wales to estimate likely changes in diet under healthy eating guidelines, and the consequences this would have on agriculture and land use in England and Wales. The first step entailed imposing nutrient restrictions on food consumption following dietary recommendations suggested by the UK Department of Health. The resulting diet was used, in a second step as a proxy for demand in agricultural commodities, to test the impact of such a scenario on food production and land use in England and Wales and the impacts of this on agricultural landscapes. Results of the diet optimisation indicated a large drop in consumption of foods rich in saturated fats and sugar, essentially cheese and sugar-based products, along with lesser cuts of fat and meat products. Conversely, consumption of fruit and vegetables, cereals, and flour would increase to meet dietary fibre recommendations. Such a shift in demand would dramatically affect production patterns: the financial net margin of England and Wales agriculture would rise, due to increased production of high market value and high economic margin crops. Some regions would, however, be negatively affected, mostly those dependent on beef cattle and sheep production that could not benefit from an increased demand for cereals and horticultural crops. The effects of these changes would also be felt in upstream industries, such as animal feed suppliers. While arable dominated landscapes would be little affected, pastoral landscapes would suffer through loss of grazing management and, possibly, land abandonment, especially in upland areas.  相似文献   

2.
The expert-based approach to landscape assessment developed in North America during the 1970s is still largely used in planning. It has proved its usefulness for the protection and the management of landscapes with remarkable visual attributes. However, facing growing social demands for the quality of surroundings, ordinary landscapes also raise great challenges for planning. But, to what extent is the expert-based approach to landscape assessment able to capture the value of these ordinary landscapes? What might be the more appropriate method for this purpose? This paper addresses these questions through an empirical research project in areas of intensive agricultural use in Quebec (Canada). The aim of this research was to measure and compare the ability of an expert-based approach and of a lay people-based approach, also named experiential approach, to capture the most valued components of ordinary landscapes. These methods were applied to two study areas. The first one has no recognised landscapes in any planning document while the second one has recognised landscapes for regional tourism. Forty-six inhabitants and an expert were invited to evaluate the landscapes of the study areas. The results have allowed comparison of the components valued by the expert and by the inhabitants as well as the criteria used in the assessment. They revealed differences between the expert and the lay people assessment. For inhabitants, the value of ordinary landscapes is based on a set of criteria related to emotion, to everyday experience and to their intimate knowledge of places. Thus, the formal visual criteria used by the expert appear to be clearly less important in the evaluation by lay people. As the expert perspective in landscape assessment is more closely associated to the experience of an individual which cross the territory (ex.: tourist), this paper concludes that to capture the value of ordinary landscapes in a planning perspective, a combination of approaches is necessary.  相似文献   

3.
Credibility of institutions: Forestry, social conflict and titling in China   总被引:2,自引:0,他引:2  
Peter Ho   《Land use policy》2006,23(4):588-603
In the reform of a forestry sector governed by centralist, socialist principles towards a sector suited to the challenges of the market economy, the Chinese government needs to establish institutions that can be perceived as credible by social actors. In other words, the creation of institutions that rally sufficient social and political support in order to be effective. Against this backdrop, this article consciously opts to refer to institutional “credibility” instead of the more fashionable concept of institutional “trust”. Whereas scholarly discussions about trust focus more on the relation of trust between social actors, credibility puts more emphasis on the institution itself, and the role of government in its successful creation or failure. Failure to effectively undertake institutional reform might put the social acceptability or credibility of institutions at risk, and can lead to the emergence of “empty institutions” with little, or even, a negative effect on social and political actors. Applying this concept to China's forestry sector, this article identifies three critical areas that call for careful rethinking how to “get institutions right”: the titling of forest holdings; the restructuring of the forest administration; and the design of forest laws and policies with particular reference to lease and ownership.  相似文献   

4.
This study analyses the impacts of de-coupling of agricultural support from production in Finland. A dynamic agricultural sector model, which includes 17 production regions and endogenous investments and technical change, is used in the analysis. Investment in different production techniques is dependent on the relative profitability and the spread of each technique in the population of heterogeneous farms. There are relatively few large farms which use efficient production techniques in Finland. De-coupling weakens the incentive for investment in dairy production and causes a temporary but significant slow down in dairy investments and technical change. Consequently, de-coupling is likely to result in a significant drop in milk and beef production in the next 10-20 year period if no corrective measures are taken in agricultural policy in less-favoured areas such as Finland. However, a slow recovery of investment and output levels are expected in the long run.  相似文献   

5.
In recent years, numerous articles have addressed management strategies aimed at assisting forests to adapt to climate change. However, these seldom take into account the practical and economic implications of implementing these strategies, notably, supply of forest plants and seed. Using semi-structured interviews with practitioners involved in the plant and seed supply chain in Great Britain, we highlight a series of practical and economic bottlenecks commonly encountered in the supply of locally sourced seed and domestically produced planting stock for native woodland and hedging markets. We find that adoption of alternative seed sourcing strategies, designed specifically to account for directional climate warming, is likely to exacerbate existing problems by adding further complexity to decisions nurseries make about tree species and seed origins to produce. The lack of long-term market predictability brought about by the current configuration of forestry grants and regulations and, in particular, the administrative systems for processing grant applications is identified as a major impediment to having a sustainable and competitive supply of home-grown and currently adapted planting stock. Finally, the time and effort it takes to supply healthy plants for native woodland creation projects deserves much wider recognition throughout the industry and will be crucial if planting objectives are to be met sustainably.  相似文献   

6.
Urban sprawl is considered by most environmental scientists and urban planners to be a serious environmental problem. However, public perception about parking availability often forces planning offices to recommend parking lot sizes that exceed daily demands. The recent trend of increasing the size of stores, churches and even schools comes with increasing the size of parking lots that service these buildings. The objective of this paper is to analyze space allocation of parking lots in a typical midwestern county and to estimate the supply of parking spaces to potential demand. We also estimate the loss of ecosystem services represented by the area of parking lots in this county. We found that parking lots cover 5.65 km2 (1 397 acres) of Tippecanoe County, Indiana which implies that 0.44% of the county area is devoted to parking lots. Our results show that there are approximately 2.2 parking spaces per registered vehicle, that parking lots make up more than 6.57% of the total urban footprint in this county, that the area of parking lots exceeded the area of parks in the city limits by a factor of three and that parking lot runoff and pollutants are significant compared to runoff and pollutants from these areas prior to their conversion to parking lots. As other authors have done before us we lament the poor use of land in urban regions of the United States, and encourage planners to think creatively about the use of land for parking.  相似文献   

7.
The environmental, cultural and economic consequences of land use change, including abandonment of agricultural use, have been recognized for a long time. It has often been assumed that the transformations of the agricultural systems in developed countries (and particularly in Europe) took place, for the main part, in the immediate years after the Second World War. In this paper we present a review of different statistical and cartographic sources available for a peripheral region in Europe (Galicia, Spain) characterized by small-scale farming and a very fragmented property system, that suggests otherwise: modernization of agriculture apparently took place without major changes in agricultural area until the country gained access to the European Economic Community, and the effect of Common Agricultural Policy reforms during the decade of 1990 is suggested as a major driver for the net decrease of agricultural area in the region between 1956 and 2004. On the other hand, this paper emphasizes the spatial complexity of agricultural abandonment with a case study, showing a large degree of variability at municipal scale and thus the need of future EU-level projects to work at least at municipal (Local Administrative Units 2, LAU 2) level. Finally, a multinomial logistic model for observed changes is included that shows how biophysical limitations were the main drivers behind abandonment of agriculture at parcel scale, while structural qualities related to property structure were strongly associated to the incorporation of former shrublands to agricultural use. Besides, Farm Structure Surveys were revealed as an unreliable source for the assessment of changes in total agricultural area in the studied region.  相似文献   

8.
Increased pressure on ecosystems and enhanced competition over the use of natural resources makes it necessary to develop sustainable methods for natural resource management (NRM). However, NRM is a complicated issue. It involves numerous stakeholders, with different needs, resources and perceptions of nature. Stakeholder participation will necessarily be selective, based both on theoretical assumptions about who is a legitimate stakeholder and unevenly distributed power among stakeholders. Although stakeholder involvement is important, sometimes the theory appears to be rather blunt. It has been suggested that, since different categories of stakeholders embody different perceptions of nature, cultural theory could provide important additional criteria for stakeholder involvement. Based on field studies in Naivasha, Kenya, this paper analyses pros and cons of stakeholder analysis and investigates the usefulness of cultural theory for improved stakeholder analysis.  相似文献   

9.
Agricultural intensification and abandonment have been identified as two of the more prominent and polarizing drivers of landscape change in Europe. These transitions may induce deterioration in landscape functioning and character, particularly in cultural landscapes demonstrative of evolving human-environment dynamics that have sustained environmental benefits through time. Cultural and behavioral motives are important root influences to such landscape transitions, yet efforts to address landscape degradation are often hampered by a failure to account for the heterogeneous decision-making nature of its agents of change and the inherent complexity of socio-ecological systems. Novel techniques are required to further disentangle responses to multi-level drivers and discuss alternative landscape development trajectories. Agent-based models constructed by means of participatory approaches present increasingly applied tools in this context. This study sought to capture and model the future perspectives emerging from presently occurring farming discourses in the region of Gera (Lesvos, Greece), characterized by persistent abandonment of its traditionally managed olive plantations. We constructed an agent-based model iteratively in collaboration with the local farming community and experts in landscape research. Empirical findings informed the model through the construction of a farmer typology, revealing a heavy reliance of the farming community upon sectorial profitability, prevalent cultural farming motives and emerging landscape initiatives. The model examined the de-coupled role of agricultural profitability and landscapes initiatives in shaping the behavior of land managers, mapping alternative landscape futures over a period of 25 years. Model results illustrate both increased profitability and action by landscape initiatives are required to reverse abandonment trends within the simulated time frame. The hypothesized ability of landscape initiatives to maintain and promote a cultural drive amongst adhering farmers is crucial for securing behavioral transformations towards professionalism. This study confirmed agent-based modelling to be intuitively received by stakeholders who significantly contributed to model structure refinement and the rejection of a status quo scenario.  相似文献   

10.
黑龙江省是资源大省,近几十年,在粮食、木材和石油方面为国家做出了突出贡献的同时,资源过度开发甚至破坏的现象十分突出;针对黑龙江省的自然资源与环境的状况,分析自然资源过度消耗与环境退化的经济原因。  相似文献   

11.
我国粮食生产主要影响因子的灰色关联动态分析   总被引:7,自引:0,他引:7  
根据1994~2004年我国粮食生产相关指标的统计数据,运用灰色关联理论对影响我国粮食生产的主要因素进行了关联动态分析,定量分析了粮食总产量与各因子的关系密切程度,指出了粮食单产、粮食播种面积、有效灌溉面积及受灾面积是影响中国粮食生产的最重要因素;提出了相关的发展对策。  相似文献   

12.
13.
近年来,煤炭生产事故频发,安全生产问题日益突出。加强安全生产监督,理应充分发挥科技手段的重要作用。基于计算机网络的图像监控系统,实时地捕捉监控点的信息,给生产监督管理工作中的技术手段带来了前所未有的局面。文章从煤炭安全生产监督管理的概念、特点、保障措施、组织框架以及应用中应注意的问题等方面入手,论述了图像监控系统在煤矿安全监管中的应用。  相似文献   

14.
Intensification of agriculture and industry in salinized areas poses a risk of secondary salinization. Thus, comprehensive and spatially explicit assessments are needed to assist government in developing ecologically sound policies. Few assessments have comprehensively quantified the impacts of multiple anthropogenic activities on salinization as environmental interferences and salinity autocorrelation are largely neglected. This study tried to perform such an assessment by identifying the nature of human impacts on salinization from three aspects in the Yellow River Delta (YRD) of China. A versatile GIS-based spatial autoregression (SAR) was applied to nine selected explainable variables in six sub-region models. Sub-region model was verified as an effective tool of normalizing environmental interferences because more useful spatial information was provided compared to the whole region model. GIS-SAR model fit better and performed better in quantifying human activities, compared to the conventional ordinary least square regression (OLSR) model, as SAR can deal with spatial autocorrelation in soil salinity. Among the well-defined key determinants, oil exploitation and saline aquaculture were aggregative to salinization but only in originally highly saline sub-regions, such as coastal zone and Gleyic Solonchaks (coastal saline moisture soil) area. Two agricultural activities, crop plantation and fertilization, were mainly ameliorators in most sub-regions. The most effective salinization alleviation occurred in moderately saline sub-regions, such as floodplain and Salic Fluvisols (saline moisture soil) area, which benefitted from the development of agroforests and farm ponds. The SAR sub-region model is spatially explicit for spotting the hazardous areas and some suggestions were also provided for the policy makers.  相似文献   

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