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51.
以广东省五华县为例,以行政村为单元,在政策指标测算法的基础上,从自然环境状况、经济保障能力和社会因素等3方面构建理论潜力修正模型,将理论潜力修正为可实现潜力,并根据土地适宜性评价估算增加耕地潜力,以期为科学编制农村土地整治规划提供依据。研究表明,五华县农村居民点用地布局分散、规模小、空间差异显著,呈现出沿河谷、沿交通线路分布的典型特征。到2020年,农村居民点整治理论潜力为5683.91 hm2,北部村庄的整治潜力较大;可实现潜力修正系数为0.54,与理论潜力相差较大,各行政村之间差异明显;新增耕地潜力系数介于0.32-0.94,预计新增耕地1943.41 hm2,琴江、五华河沿线村庄的新增耕地潜力较大。建议实施差别化的农村居民点整治对策,推进五华县农村土地整治。  相似文献   
52.
杨洋  马学广  王晨 《人文地理》2015,30(5):91-98
基于长时间序列夜间灯光遥感数据,本研究从国家、八大经济区、省、地等四个尺度综合分析了中国1992-2010年土地城镇化水平时空动态特征。结果表明,在1992-2010年间:中国土地城镇化水平增长迅速,年均增长率为8.34%,明显高于同时期人口城镇化水平增长速度;土地城镇化水平区域差异十分显著,东部沿海经济区在八大经济区中土地城镇化水平最高且增长速度最快,香港、澳门特别行政区土地城镇化水平远高于其它省区;土地城镇化的热点区域主要集中分布于长三角、山东半岛、海峡西岸等11个城市群地区。  相似文献   
53.
抗日战争时期的史家与史学   总被引:1,自引:0,他引:1  
抗战时期,广大爱国史学工作者紧扣时代脉搏,以抗敌御侮为学术主旨,自觉为抗战提供历史借鉴、精神动力和智力支持,面向大众开展历史知识的普及教育,在抗日民族统一战线的旗帜之下展开思想交锋和学术争鸣;其学术活动在回应时代需求的同时,也使史学自身得到丰富和发展。  相似文献   
54.
Ritual landscapes at sea are marked in the cognitive world of coastal people by a primary antagonism between sea and land. This contrast is negotiated by liminal 'foreign' agents, selected for their symbolic adherence to either part. The primary source of maritime culture is fishing as a survival of past hunter-gatherer societies. Forms of religious or magical management of this contrast are manifold, from recent superstitious magic to powerful symbols in ancient worship, objects, art, architecture and cult. Also described are ways of using the sea on land as a magic metaphor and a fundamental point of reference. Related dichotomies and ways of negotiating them, such as the liminal agent, exist elsewhere in the cognitive world of pre-industrial societies, so these ideas could have applications in archaeology.
© 2005 The Nautical Archaeology Society  相似文献   
55.
There is a growing movement toward collaborative stakeholder participation in environmental policy. Rather than calling for a reliance on government officials to solve environmental problems, this approach calls for empowering a community of stakeholders to contribute meaningfully. Scholars examining citizen participation have investigated the performance of such efforts. This study examines one important aspect of performance, the impact of stakeholder participation on policymaking at the local level. A multiple‐case analysis of county‐level, community‐based task forces working on farmland preservation planning in Ohio, U.S., reveals patterns of policymaking processes and the near‐term impacts of collaborative planning. These patterns are linked to scholarship using prior empirical studies as well as the Institutional Analysis and Development framework, which integrates physical, social, and institutional variables to examine collective decision‐making related to natural resources. Results indicate that the degree of policy change is associated closely with local contextual factors, rather than internal group factors often emphasized in studies of citizen advisory committees and collaborative groups.  相似文献   
56.
Despite being a major site of recent population growth and, arguably, a key arena for sustainability concerns, the rural‐urban fringe has received relatively little attention in the literature concerning Australian cities and urban policy. To address this shortcoming the authors review post‐World War II efforts to plan the rural‐urban fringes of Sydney and Adelaide and find a number of issues for contemporary policy‐makers. First, the fringe is becoming increasingly complex due to multi‐faceted demographic change, a broadening economic base and demands for better environmental management, all within the context of an evolving understanding of sustainability. Second, water resource management, partly under the auspices of integrated natural resource management, is assuming a much higher priority than in early fringe planning endeavours, which emphasised urban containment, agricultural land protection and landscape conservation. Third, and partly as a consequence of this shift of priorities, there is also evidence of changes to the nature and focus of policy tools used in the fringe, with land management concerns now cutting across traditional land use planning. Finally, and fundamentally, these observations raise questions about how future governance of the fringe should be organised. Together these four themes pose an enthralling series of challenges for policy‐makers for which much more research and discussion are needed.  相似文献   
57.
Research on past human diets in the southern Lake Titicaca Basin has directed us to investigate the carbon and nitrogen stable isotopes of an important dietary element, fish. By completing a range of analyses on modern and archaeological fish remains, we contribute to two related issues regarding the application of stable isotope analysis of archaeological fish remains and in turn their place within human diet. The first issue is the potential carbon and nitrogen isotope values of prehistoric fish (and how these would impact human dietary isotopic data), and the second is the observed changes in the fish isotopes through time. Out of this work we provide quantitative isotope relationships between fish tissues with and without lipid extraction, and a qualitative analysis of the isotopic relationships between fish tissues, allowing archaeologists to understand these relationships and how these values can be applied in future research. We test a mathematical lipid normalization equation to examine whether future researchers will need to perform lipid extraction procedures for Lake Titicaca fish. We also analyze a number of aquatic plants to better understand the range of isotopic signatures of the Lake Titicaca ecosystem. We use these data to better understand prehistoric human diet and the role that fish may have played in the past as well as potential changes in local lake ecology through time.  相似文献   
58.
南京滨江开发区吴墓出土建衡元年买地券券文中未释读、误读或漏读的部分,可补释校订为十一月丁巳朔、丹杨、卜安冢宅、从地主古糸买地、糸卖承买、先立可信等。虽然券文从形式到内容仿照现实生活中的地契,但其中的面积、地价和地主姓名仍有可能出于虚构。  相似文献   
59.
The form of many Canadian cities has dramatically evolved over the past six decades due to urban sprawl. Several patterns can characterize this evolution including unlimited horizontal expansion of the city, leapfrog, and low‐density residential development at the outskirts, and widespread strip commercial and power centre retail development. Hamilton, Ontario is an example of a Canadian city that has experienced suburbanization and sprawled development for several decades. However, the nature of this sprawled development is unclear and its impact on urban form is not entirely understood. In this article, several hypotheses pertaining to sprawled land development and urban form are postulated and tested. The tests rely on point source data of the developed land parcels in Hamilton during the period 1950–2003. A number of spatial statistics techniques, including kernel estimation and complete spatial randomness (CSR) K‐function tests, are employed to examine the emerging nature of urban form. We hypothesize that while the city has been sprawling, the ongoing land development process is leading urban form into multinucleation. To support this assumption, we further hypothesize the existence of an interdependent spatial relationship between residential and commercial land uses at the emerging nuclei. Accordingly, we examine the strength of co‐clustering among these land use activities over time. The findings indicate that while the city has been sprawling, several consequent urban nuclei with mixed land use activities have been emerging and become more visible in recent years. This is an indication that the city's form is progressively becoming multinuclear. Furthermore, the estimates for the 1990s indicate interdependence between the locational patterns of residential and commercial land development. Co‐clustering between these two types of land uses is bi‐directional and occurs at a time lag of three to seven years. These findings affirm the existence of interdependence between land use activities at the observed nuclei, which support the emergence of a multinucleation.  相似文献   
60.
唐常春  樊杰  陈东  胡望舒 《人文地理》2013,28(2):98-103
以长株潭结合部暮云镇为例,主要采用2004与2010年土地利用数据,从动态变化与多维综合视角,对行政边界区域土地利用与空间发展的特征、机制及问题进行系统分析,在此基础上归纳理论模式。研究表明:①暮云镇土地利用结构由农村型向城镇型快速转变,城镇用地比重年均约增加2个百分点,其中居住、教育科研、交通和工业等用地增加显著;②受主体功能定位、过境通道建设、周边城市辐射差异和规划管理制度变迁等因素影响,暮云镇空间格局与扩张模式快速演变,芙蓉大道沿线新增城镇用地占全镇82.78%,北、中、南区域开发强度分别上升20.95%、7.96%和1.58%,城镇用地平均图斑面积增长2.04倍。③研究区土地利用与空间发展存在诸多阶段性和结构性问题,应加强综合路网建设、公共设施用地供给、建设用地优化布局与集约利用以及生态环境保护。  相似文献   
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