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21.
当代地理学特征:发展趋势及中国地理学研究进展   总被引:17,自引:3,他引:17  
地理学是一门研究地球表层自然要素与人文要素相互作用及其时空变化规律的科学,它广泛运用现代科学技术手段,具有跨越自然科学与社会科学的性质。面对当前全球变化和可持续发展的世界性科学问题,地理学家根据学科特点和领域优势,抓住机遇、迎接挑战。目前主要研究地球表层系统各界面间的物理、化学、生物及人文过程,探讨多种过程的相互作用机理,探求人类活动与资源环境间相互协调、可持续发展的规律。地理学以“格局—结构—过程—机理”的研究思路贯穿始终。随着新技术、新方法的使用以及观测资料的不断积累,实验测试数据质量的提高和数据量的增加,当今地理学的研究在空间尺度上同时向微观、宏观两个方向扩展,模型研究不断科学化,已具备现代科学的主要特征。总体上,表现为部门地理研究深化,区域综合研究加强。长期以来,中国地理学在自然地理的综合研究、地表自然过程研究、城市与区域发展研究,以及面向社会现实的应用基础研究等方面取得了较好进展。  相似文献   
22.
Abstract: Expressions of dissatisfaction about the post‐compulsory Geography curriculum in the early 1970s were unusually concerted, leading to the creation of a National Geography Curriculum Committee. This essay reviews this history and the resulting Syllabus for Schools: Geography Forms 5–7 as a prelude to a discussion of contemporary curriculum development. The essay argues that curriculum development from 1975 and the ‘education reforms’ of the late 1980s failed to produce conditions in which satisfactory outcomes for a Geography curriculum can be assured in 2005, and that a new and concerted period of participation in curriculum discussion is required. Some goals for this process are outlined in the final section of the paper.  相似文献   
23.
In this paper, the results of a survey conducted in the Cukurova region of Turkey are presented. The aim of this research is to identify groups of farmers who differ in their risk sources and risk management strategies. The respondents to the survey were divided into three risk attitude groups, risk averse, risk seeking and risk neutral. Factor analysis has been conducted on information obtained from 112 farmers in 2000. From the findings of the research, risk sources were labelled as environmental, price, catastrophe, input costs, production and technological, political, finance, personal, marketing, health and social security. The dimensions of risk strategies were named as diversification, off-farm income, marketing, planning, financing and security.  相似文献   
24.
The recent rise in agricultural commodity prices and the expectation that high price will persist have triggered a wave of farmland expansion in regions where land resources are still available. One such region is the former Soviet Union, where the collapse of socialism caused massive agricultural abandonment and where some of these lands are now being brought back into production. Yet, the extent and spatial patterns of recultivation, and what determines these patterns, remains unclear. We examined the extent of recultivation of abandoned agricultural land in Ukraine since 2007 using a new, satellite-based recultivation map and assessed the effect of biophysical and socioeconomic determinants on recultivation patterns using boosted regression trees. We found key predictors of recultivation to be related to the suitability of land for agriculture (i.e., soil quality, temperature). Accessibility to major cities was also important, with most recultivation happening closer to settlements, but this influence varied across Ukraine. Variables related to agricultural management (fertilizer input, mechanization) and demography were negligible in explaining recultivation in our analyses. These factors suggest that recultivation patterns were primarily driven by factors related to land productivity, with recultivation focusing on the most promising areas. Given the remaining large amount of unused agricultural land in Eastern Europe and the former Soviet Union, and considering that much abandonment occurred in areas only marginally suited to agriculture, our findings provide important insights into where recultivation can be expected to happen and thus for assessing the potential socioeconomic and environmental impacts of recultivation.  相似文献   
25.
通过对国际上的政治地理学旗舰性杂志《Political Geography》2005-2015年期间391篇成果的分析,总结出国际政治地理学研究的主要研究议题为:边境与边界,环境政治,空间与尺度,领土和主权以及安全问题,选举地理,社会和文化政治,其中空间与尺度,领土和主权以及安全问题,社会和文化政治几个方向研究成果占较大比例,而其他三个方向则相对较少.通过研究方法分析发现,国际政治地理学主要采用定性分析的方法,尤其是民族志和文本分析的方法,定量分析的使用存在一定的局限性.最后,从该杂志的研究对象和研究机构两个方面的分析归纳出:欧美主导的发达国家(尤其是英国和美国)对世界政治地理学话题的学术霸权与世界南,北差异发展具有一定的相关性.在中国综合国力日渐增强,参与国际事务能力不断提高以及作为新兴的地缘政治力量崛起的社会历史背景下,政治地理学经世致用之能亟待被展现.因此,中国政治地理学发展作为发展中国家的声音势必将越来越洪亮.  相似文献   
26.
Family farms have long generated income from agricultural tourism including U‐picks, wagon rides, corn mazes and petting zoos, but contemporary agricultural tourism reflects much greater sophistication in terms of product variety, services, activities, and marketing. In Michigan, farm operators have moved beyond classic products and activities and the traditional consumer base. New sources of revenue derive from classes on beer, cider, mead and wine making, yarn spinning, perfume/soap‐making, farm markets, fishing, educational classes, school tours and hospitality including weddings and on‐farm restaurants. This case study of Michigan agricultural tourism reports results from a systematic survey of 154 agritourism operations conducted throughout the state during summer and fall of 2013 with a focus on the economic benefits of the fast‐changing sector. This study summarizes tax revenues, sales and employment trends for the farm operations participating in the survey but also quantitatively assesses the contribution of agricultural tourism to Michigan's economy through an extrapolation of the sample to estimate state‐wide totals. Results from OLS multivariate regression analysis intended to identify relationships between employment, advertising and scale to gross sales per day are also reported. These analyses show the importance of agricultural tourism to rural and peri‐urban places in Michigan and throughout the nation, while raising concerns about a growing division between large and small operators and what this growing gap may mean for the future of the sector.  相似文献   
27.
At present, flash drought occurs globally and regionally and causes a lot of socio-economic loss in a very short time. Therefore, flash drought has been regarded as one of the hottest issues in drought research. However, flash drought monitoring, prediction and decision-making have encountered a lot of challenges due to its multiple driven factors and complex spatio-temporal process. Aiming at this problem, this paper focused on the agricultural land in China, and analyzed the spatio-temporal distribution of three kinds of flash droughts (i.e., precipitation-deficit, high-temperature, and composite flash droughts) from 1983 to 2015. We studied the occurrences, duration, spatial distribution, temporal distribution, and trend of all three kinds of flash droughts. Our results demonstrated that, the occurrences of flash drought agricultural land in China increased year by year, among which high-temperature flash drought increased dramatically; duration of flash droughts had different trends, but the variations were relatively smooth; Northeast China was identified as a vulnerable area of flash drought, indicating more flash drought events and longer duration; flash droughts in China were found to concentrate in spring (high-temperature drought) and summer seasons (precipitation-deficit drought). This study is helpful for building new flash drought monitoring method and system, and it is also valuable for flash drought preparedness on regional scale.  相似文献   
28.
Climate and land use patterns are expected to change dramatically in the coming century, raising concern about their effects on wildfire patterns and subsequent impacts to human communities. The relative influence of climate versus land use on fires and their impacts, however, remains unclear, particularly given the substantial geographical variability in fire-prone places like California. We developed a modeling framework to compare the importance of climatic and human variables for explaining fire patterns and structure loss for three diverse California landscapes, then projected future large fire and structure loss probability under two different climate (hot-dry or warm-wet) and two different land use (rural or urban residential growth) scenarios. The relative importance of climate and housing pattern varied across regions and according to fire size or whether the model was for large fires or structure loss. The differing strengths of these relationships, in addition to differences in the nature and magnitude of projected climate or land use change, dictated the extent to which large fires or structure loss were projected to change in the future. Despite this variability, housing and human infrastructure were consistently more responsible for explaining fire ignitions and structure loss probability, whereas climate, topography, and fuel variables were more important for explaining large fire patterns. For all study areas, most structure loss occurred in areas with low housing density (from 0.08 to 2.01 units/ha), and expansion of rural residential land use increased structure loss probability in the future. Regardless of future climate scenario, large fire probability was only projected to increase in the northern and interior parts of the state, whereas climate change had no projected impact on fire probability in southern California. Given the variation in fire-climate relationships and land use effects, policy and management decision-making should be customized for specific geographical regions.  相似文献   
29.
The formal opportunity to learn geography in the United States is unevenly distributed across space, creating possible geography deserts. Data on the number of exams taken in Advanced Placement Human Geography (APHG) and bachelor’s degrees earned in geography are mapped at the state and regional scales. Normalized rates are ranked and grouped into quintiles. For APHG exams, states in the southeastern region of the United States are in the uppermost quintiles while states in the northeastern region are in the lowermost quintiles. The pattern for bachelor’s degrees in geography is somewhat the spatial inverse of that for APHG.  相似文献   
30.
Although 97% of U.S. farms are “family-owned,” little research examines how gender and sexual relationships – inherent in familial dynamics – influence farmers’ practices and livelihoods. Gender and sexual dynamics – shaped by race and class – affect who is considered a farmer, land management decisions, and access to resources like land, subsidies, and knowledge. We use feminist and queer lenses to illuminate how today’s agricultural gender and sexual relations are not “natural,” but when left uninterrogated are constructed in ways that harm women and queer farmers while limiting potential to develop sustainable practices. Women and queer farmers also resist, “re-orienting” gender and sexual relations in ways that expand possibilities for achieving food justice and ecological sustainability. We offer “relational agriculture” as a tool for making visible and re-orienting gender and sexual relations on farms. Relational agriculture brings sexuality into food justice and demonstrates the centrality of gender and sexuality to agricultural sustainability.  相似文献   
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