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151.
152.
遥感和GIS支持下的湘西北喀斯特山区县域农业生态环境脆弱度评价 总被引:4,自引:0,他引:4
将GIS和遥感技术引入传统的脆弱度定量评价方法,采用专家咨询法和层次分析法建立指标体系,应用GIS建立评价模型,对典型的湘西北喀斯特山区农业生态环境脆弱度进行了评价。结果显示,研究区存在澧水河谷和以罗水乡为中心西北部两个农业生态环境脆弱度高值区,农业生态环境脆弱度分布与由人类活动所致的胁迫脆弱度分布匹配。根据评价结果,为了避免农业生态环境退化,应采取加强东南和西北山区坡耕地退耕还林、增加水田比重和减少西北农业区农药、化肥和地膜的使用量等措施。 相似文献
153.
地理信息系统在资源环境评价与管理中的应用 总被引:1,自引:0,他引:1
介绍了地理信息系统在资源环境评价与管理中的具体功能,讨论了GIS,RS,GPS在资源环境特别是水资源和精准农业管理上的应用,并指出地理信息系统作为一种信息处理工具能满足数字信息获取的三个阶段:数据的收集、数据的分析、数据的转换和信息处理。 相似文献
154.
Lars Krogh M.Sc. 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):90-100
Krogh, Lars: The Major Soils of a Village in Northern Burkina Faso. Geografisk Tidsskrift 93:90–100. Copenhagen 1993. In the Oudalan Province of Sahelian Northern Burkina Faso soil investigations have been carried out in order to evaluate the sustainability of millet production with emphasis on the dynamics of soil fertility. Some results of pedological investigations carried out in 1990 are included. Three commonly occurring soil types in a village territory are examined and their genesis and fertility discussed. Analyses show that the soils are inherently low in organic matter. The level of macro-nutrients is low, soil structure is weak or unfavourable: all probably due to a combination of natural and human factors. Crop yields are generally low and cannot be raised without more intensive cultivation. 相似文献
155.
Nathan Scholl 《The Professional geographer》2013,65(2):286-287
This study assessed the spatial distribution of vulnerability to extreme heat in 1990 and 2000 within metropolitan Phoenix based on an index of seven equally weighted measures of physical exposure and adaptive capacity. These measures were derived from spatially interpolated climate, normalized differential vegetation index, and U.S. Census data. From resulting vulnerability maps, we also analyzed population groups living in areas of high heat vulnerability. Results revealed that landscapes of heat vulnerability changed substantially in response to variations in physical and socioeconomic factors, with significant alterations to spatial distribution of vulnerability especially between eastern and western sectors of Phoenix. These changes worked to the detriment of Phoenix's Hispanic population and the elderly concentrated in urban-fringe retirement communities. 相似文献
156.
157.
Medicinal plant cultivation and gathering can play a vital role in the course of livelihood diversification for the marginalized population living in remote areas. However, this requires an integration of the respective production networks that allows the producers a fair and reliable income and does not endanger rare plant species. This paper analyses the situation within the Indian state of Uttarakhand, and identifies structures and entities hindering medical plant cultivation and its potentials. Based on the broad network understanding of the Global Production Network approach, the case study focuses on the middlemen and their hidden embeddedness. It shows how governmental organizations and in particular non‐governmental organizations and farmers' institutions can help to overcome clandestine structures of illegal trade and contribute towards a redesign of the medicinal plant network in a more equitable and transparent way. 相似文献
158.
Richard Grant 《Urban geography》2013,34(1):86-108
Abstract The full diversity of economic activities in the informal economy is not well understood. The apartheid legacy of limiting informal entrepreneurship explains the most obvious geographical patterns in South Africa. After a decade and a half since the end of apartheid, however, knowledge about the places from which informal entrepreneurs operate is incomplete. Retailing is overemphasized and production firm entrepreneurs, both male and female, remain a neglected spatiality. This study reports on a survey of 100 firms in Soweto and in-depth interviews with 30 firm owners. The findings challenge the representations of isolated urban entrepreneurs dependent on inherited social capital and of women's exclusive engagement in retail. Entrepreneurs create their own social capital in work-related realms, but there are important gender differences. More finely tuned conceptualizations of entrepreneurs and of gendered working spaces need to be developed so that policy does not perpetuate unitary myths and incomplete spatial representations. [Key words: entrepreneurship, Soweto, informal economy, gender.] 相似文献
159.
国内外有机农业发展演化与区域比较研究 总被引:2,自引:0,他引:2
本文对世界有机农业发展演化进行梳理,将其发展历程分为产生、发展和增长阶段,并介绍了各阶段的主要特点。以大洋洲、北美洲、欧洲和亚洲有机农业发展较好的区域进行典型性对比分析,选取有机农田面积、有机农业从业人员和有机产品销售等标志性指标,综述了世界有机农业的发展动态,并对各地区有机农业发展的成功经验进行总结。简述我国有机农业的发展演化,从有机产品贸易额、有机农产品产区分布和有机企业空间分布总结了我国有机农业的发展现状,并提出我国未来有机农业的发展对策。 相似文献
160.
Abstract Groundwater development potential in northern Ghana (108 671 km2) has been assessed by combining spatial layers for five critical factors—recharge rate, regolith thickness, transmissivity, borehole success rate and static water level—through a multi-criteria analysis approach to rank development potential from the viewpoint of groundwater availability and accessibility at a resolution of 1 km2. The results indicate a high potential for development in the study area, as about 70% of the area was found to have high to moderate groundwater availability, while 83% has high to medium groundwater accessibility. Comparing the two main hydrogeological environments, the Precambrian Basement rocks (PCB) area was found to generally have a higher groundwater development potential than the Voltaian Sedimentary rocks (VSB). More detailed investigation revealed that the VSB can produce a small proportion of exceptionally high-yielding boreholes that can support large-scale irrigation. A test of the reliability of results showed that generally, the majority of high- and low-yielding boreholes fall in areas predicted by the model as having high and low groundwater availability, respectively. Editor D. Koutsoyiannis; Associate editor D. Hughes Citation Forkuor, G., Pavelic, P., Asare, E., and Obuobie, E., 2013. Modelling potential areas of groundwater development for agriculture in northern Ghana using GIS/RS. Hydrological Sciences Journal, 58 (2), 437–451. 相似文献