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991.
Satellite imagery has proven potential in farm level applications, especially in the US Upper Midwest where the farm sizes are large enough to be studied using high and medium resolutions. In order for farmers to use this technology to improve their productivity and income, it is imperative that they be sufficiently exposed to the technology so that they are able to take full advantage of it. Training of farmers and ranchers in satellite imagery use started at the University of North Dakota in 2000 and has been refined over time. The basic ‘hands on’ training involves downloading imagery from the Upper Midwest Aerospace Consortium (UMAC) website, downloading and use of free visualization software programs available on the web and an introduction to the various application possibilities. Advanced training, which involves more complex extraction of useful information from digital images, is also available to those who complete the basic training. Over 500 farmers, ranchers, crop consultants and other end users have been trained through this programme and the results are beginning to show through the success stories of cost savings and environmental benefits that have emerged.  相似文献   
992.
The Kou watershed is characterized by important water resources used for drinking, agriculture (especially in the irrigated areas), industry and the preservation of aquatic fauna and flora. For several decades, there has been increasing pressure on the Kou's water resources, partly because of the expansion of the irrigated agricultural areas. This study was conducted to examine this issue, focusing on one specific irrigated area. In order to monitor the expansion of irrigated areas in developing countries, a low-cost remote sensing method based on Landsat images and aerial photographs was developed. The method is based on maximum-likelihood classification, followed by backward and forward change detection analysis requiring agronomic expertise. Using pixel trajectory analysis, the method connects all pixels to their consecutive states in order to correct their current states. The study showed that the irrigated area has expanded by almost 70% over 20 years, with most of this expansion occurring in the past 10 years. The method, if validated, could be used to obtain better information on past occupation in the rural irrigated areas for which there is currently no archived data, making temporal analyses impossible.  相似文献   
993.
Abstract

In this paper we analyse all currently available simulated climate scenarios, proposed by the Spanish Agency of Meteorology (AEMET), for the period 2010–2040 on the geographical area covered by the Júcar River basin, located in eastern Spain. This is done through the validation of these scenarios using historical records, and by assessing the impact on water resources for the next 30 years by means of a hydrological model. By taking the period 1960–1990 as the control period, a careful comparison of its historical records against AEMET scenarios is performed. Although temperature records are modelled properly, precipitation data are widely underestimated in a range from 8% to 29%. This wide variability observed in the control period is also found in the precipitation scenarios for the period 2010–2040. The impact on water resources shows a great degree of dispersion, ranging from –13.45% to 18.1% with a mean value of –2.13%.
Editor Z.W. Kundzewicz; Associate editor F. Hattermann  相似文献   
994.
对2013年中期地震预测的研究结果(一年尺度)进行了阐述与分析。该预测综合了三性法判据、静中动判据和垂震底继模式,给出了2013年左右在鲜水河断裂带上发生7级以上大震的可能性很大的结论。重点预测了两个具体发生的区域,预测的区域与2013年4月20日芦山7.0级地震的震源区相差70~80km左右。预测结果震级与时间吻合,但地点上发生了偏离。文中重点回顾研究了基于三性法,静中动、垂震底继方法的预测过程。  相似文献   
995.
The aim of this study was to quantitatively assess vegetable production and consumption in an urban fringe area in Metro Manila, the Philippines. We conducted field investigations into vegetable production at a farm within a subdivision, monitored customers for 1 week at the farm's vegetable stand, interviewed customers of the stand, and conducted household monitoring and interviews to identify purchasing behavior. We also conducted an object-based WorldView-2 image analysis of a larger area to identify current and potential future vegetable farming plots and a spatial analysis using GIS to visualize the vegetable production/consumption ratio. We found that about one-third of current vegetable demand could be supplied by greater promotion of vegetable farming in vacant lots and by setting up more vegetable stands at spatial intervals less than 1-km. Subdivision regulations also influenced vegetable farming because of the level of social acceptance of caretakers of vacant lots. The current planning and institutional framework does not consider social contexts in land use and planning. We suggested that a new framework is necessary; it should consider balancing the formation of social capital and formalize planning and institutional procedures to support sustainable local vegetable production.  相似文献   
996.
根据科学性、层次性、可行性和代表性的原则,构建了五台山生态旅游发展评价指标体系,该体系包括生态旅游环境、生态旅游社区、传统文化和生态旅游发展4个子系统、12个评价要素和32个评价因子.运用熵权法确定了评价因子权重,并采用多目标线性加权函数模型对评价指标进行了综合.研究表明:1.评价结果和事实基本相符,表明构建的五台山生态旅游发展评价指标体系具有一定的科学性和可操作性;2.使用熵权法对五台山生态旅游发展评价指标赋权,计算过程简单,研究结果相对客观、公正;3.五台山生态旅游发展目前正处于发展阶段.为了提升五台山生态旅游发展水平,建议采取创新生态旅游发展方式,加快依托城镇的旅游生态建设,完善旅游社区参与机制,加强传统文化遗产的保护和管理等措施.  相似文献   
997.
Australian farmers navigate their contemporary circumstances through the use of different business and legal arrangements that are shaped by the commercial realities of farming and the aspirations of farm-owning households. In posing the question ‘Family or Enterprise?’, this paper examines the extent to which various household and farm business indicators are associated with different forms of farm ownership, namely sole proprietorships, partnerships, trusts and companies. Results from a postal survey of farm enterprises in Victoria, Australia suggest that both household and enterprise factors contribute to the business structure used, although the strongest determinants appear to be those factors that are less well understood in the rural geographical and sociological literature: household composition, farmer age and farm size. Greater scrutiny of the business instruments deployed by farmers to manage family and enterprise pressures should inform expectations of the fate of family farming in advanced financialised economies.  相似文献   
998.
Geografisk Tidsskrift, Danish Journal of Geography 106(2): 87–102, 2006

The paper presents trends in past and present land use patterns in parts of a former homeland of KwaZulu-Natal, and discusses the changing role of farming. It suggests that an understanding of the transition in rural land must take into account the impact of rural-urban relations and the Colonial and Apartheid socio-spatial policies. A sequence of map data is analysed and compared with interviews with residents of the studied area and official data concerning actual and prospected development. The data demonstrate how population pressures and changing sources of income during the Apartheid period have resulted in a land use system dominated by home gardens and some attempts to develop small-scale commercial farming, while traditional subsistence farming has gradually decreased. On this background the prospects for small-scale commercial farming are discussed. It is argued that at least four aspects may explain why commercial farming is still marginal: the troubled land allocation system, the continued dependency on cash income for successful farming, the institutional obstacles to farmers from the homeland who wish to develop market relations, and the changing territorial logics that have characterized demarcation and land use in the post-Apartheid period.  相似文献   
999.
As a multifunctional activity and land use, urban agriculture supports a range of objectives, from urban greening to food security. However, it is often left out of urban policy. As a result of the highly contextual and cross-cutting nature of urban agriculture, there are relatively few comprehensive and formalized regulatory tools to draw from. Different cities around the world are now deciding how to fit urban agriculture into the urban agenda; however, in many places urban agriculture continues to operate in the absence of legitimization due to its relatively mobile and dynamic nature. This article looks at the importance of local and central governments in promoting sustainable urban agriculture. Through participatory action research, it examines the cases of Dar es Salaam, Tanzania and Copenhagen, Denmark to understand stakeholder interactions, as well as present and future barriers to the conservation of existing urban agriculture and future initiatives. The findings suggest that municipal recognition and institutional support for urban agriculture is an important component in increasing the sustainability of related initiatives. Local and central government plays a role in the legitimization and institutionalization of urban agriculture through the facilitation of multi-stakeholder processes, policy development and the conservation and allocation of land.  相似文献   
1000.
Agriculture is often not included in the baseline greenhouse gas (GHG) emission inventories created for local low carbon economy plans in Poland and other European countries. We therefore estimate the size of the carbon footprint from agricultural sources and indicate the share of agriculture in the total GHG emissions in selected Polish communes (LAU level 2). We propose a solution whereby local government units can estimate their carbon footprint independently and monitor the impact of actions taken to reduce emissions. The value of the carbon footprint from agriculture in the selected communes varies from .5 to 46.5 thousand Mg CO2eq/year, with a mean value of 12.6 thousand Mg CO2eq/year and a standard deviation of 11.4 thousand Mg CO2eq/year. Per capita, these values range from 10 kg CO2eq/year to 8.4 Mg CO2eq/year, with a mean of 1.1 Mg CO2eq/year and a standard deviation of 1.5 Mg CO2eq/year. In all communes, the contribution of agriculture to total emissions is at an average of 14% (values range from .2 to 57.4%). The obtained results confirm the appropriateness of including emissions from the agricultural sector and other related sources in low carbon economy plans.  相似文献   
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