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1.
生态恢复过程中土壤有机碳的变化 总被引：1，自引：0，他引：1
李营 《云南地理环境研究》2007,19(3):40-45,54
对长汀河田严重侵蚀地采取植灌促林生态恢复措施后生态系统的土壤有机碳、可溶性有机碳和微生物生物量碳进行了研究，并以未采取生态恢复措施的严重侵蚀退化形成的光板地与村旁受保护的风水林为对照。研究结果表明：采用生态恢复措施以后，土壤有机碳含、贮量分别达到49．03g/kg和54．14t／hm^2，分别是光板地的10．43和4．06倍；土壤DOC含、贮量分别达到1.40g/kg和0．67t／hm^2，分别是光板地的10．00倍和6．50倍；土壤MBC含、贮量分别达到2．60g/kg和1.27t／hm^2，分别是光板地的6．34倍和4．23倍。 相似文献
2.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(2-3):153-169
Initially, seven usages of the term cultural landscape in Norwegian academic literature are discussed: as an areal category, as a chronological stage of development, as the human components of any landscape, as countryside, as heritage, as scenery with esthetical qualities, and as elements in the landscape with meaning for human activity. The development of cultural landscape studies in different disciplines is then examined as a response to varying assessments of relevance for problems of society. Finally, the geographer's contribution to Norwegian cultural landscape studies is assessed. 相似文献
3.
HAYDEN LORIMER 《Geographical review》2013,103(2):177-189
A long‐form essay, arranged in a sequence of eight segments, in which I travel the countryside in search of a missing person: the scarecrow. Different aspects of the centuries‐old practice of scarecrow making and bird scaring are described. Traditionally constructed as a likeness of the human form and erected in newly sown fields as a visual method for warding off feeding birds, the existence of this striking farmland contraption is variously reported: as having all but vanished and yet of making unexpected reappearances; as materially functional and complexly meaningful; as a figure summoned up by cultural memory and personal recollection; and as a focus for mixed feelings of loss, nostalgia, estrangement, and community. A version of “geographical portraiture” accumulates, in which a single, scenic landmark stands as the essay's central fascination and simultaneously operates as a cipher for stories old and new, of agricultural society, country life, landscape politics, and rural values. 相似文献
4.
Sophie McNamara 《The Australian geographer》2007,38(1):71-91
Share house living arrangements are increasingly popular for young Australians as a result of a variety of economic and social changes such as the declining affordability of home ownership and delayed and decreasing marriage rates. Despite this rise, share housing is little researched. This paper considers the idea of ‘home’ as it exists in Inner Sydney's share houses, by examining the motivations underlying the decision to live in a share house as well as the relationships between housemates, in a sample of households. Share housing was utilised mainly as a response to social factors, such as the attraction of the lifestyle and something of a rite of passage, but was also shaped by economic considerations. Share housing was viewed by most people as transitional yet still meaningful. The vast majority considered their current dwelling to be ‘home’, mainly as a result of the intimacy of relationships between housemates, and the attainment of a sense of comfort and equality. 相似文献
5.
基于县域单元的江苏省经济空间格局演化 总被引：67，自引：5，他引：62
通过ESDA相关分析,描述了20世纪90年代以来江苏省县域经济格局在空间上的变化状况.在经济总体空间格局上,江苏省县域经济发展水平表现出很强的空间自相关性,相似的地区在空间上集聚分布,热点区的空间结构多表现为以苏州、无锡为核心的罔状空间结构,且不断的向东南方向集聚.经济增长空间格局存空间分布上表现出更多的随机性和结构的不稳定性,热点区域切换频繁,没有明显的地理集中现象.江苏经济空间格局连续性和自组织性越来越强,空间分异格局中的随机成份在不断降低,而由空间自相关引起的结构化分异越来越显著,东北-西南方向经济发展的空间差异较小,而东南-西北方向经济发展空间差异最大.最后,将江苏省经济格局演化的驱动力归结为3个方面:历史发展基础、经济区位和区域发展政策. 相似文献
6.
Borders are often portrayed in stark terms, perhaps as national‐scale threats, or as sites of suffering, or conversely as hosts to socio‐cultural symbiosis. Yet borders are many things all at once. In this paper, we use the comparative context of the US–Mexico border and the Mexico‐Guatemala border to critique what we call the ‘border as hegemony’, a borderscape constructed through obstructions, punitive policing and reinforcing the limits of state control. Instead, we propose a model of the ‘border as discord’. In our heuristic framework, diverse mobilities are embraced, interests of borderlanders are acknowledged and prioritized, and borders are interpreted not as a security threat but as a resource for change. 相似文献
7.
中国东部亚热带丘陵山地土地退化评价指标体系研究* 总被引：8，自引：0，他引：8
中国东部亚热带地区流水侵蚀所引起土地退化的形成,是由其生态环境自身的脆弱性决定的。土地退化不仅表现为土壤退化,还表现为植被退化和土地状况恶化,其发展过程是植被退化-土壤退化-地表状况恶化过程多重循环的结果。据此,提出了中国东部亚热带丘陵山地土地退化评价指标。 相似文献
8.
华北地文期命名之新见 总被引：1，自引：2，他引：1
依据山地侵蚀与平原堆积是一个地文期的两种不同表现形式，以山地侵蚀期与平原粗(包括底部的不整合面)、细(包括表层的风化壳或古土壤)粒物质堆积期相关的原则，对华北地区新生代地文期进行重新命名。晚白垩纪地文期是北台期侵蚀一卢沟桥、无极期堆积，早第三纪地文期是甸子梁期侵蚀—孔店、沙河街期堆积，晚第三纪地文期是唐县期侵蚀—馆陶、明化镇期堆积，早更新世地文期是汾河期侵蚀一固安期堆积，中更新世地文期是湟水期侵蚀—杨柳青期堆积，晚更新世地文期是清水期侵蚀一欧庄期堆积，早、中全新世地文期是板桥期侵蚀—杨家寺、高湾期堆积，晚全新世地文期是段曲期侵蚀一岐口期堆积。 相似文献
9.
Mandarine essential oils are extracted from green unripened fruits as well as from red fruits at ripening,both oils having specific uses as natural additives in the food industry.Two processes of production,pressing and peeling,are currently adopted in their production.Capillary gas chromatography with flameionization detection has been suggested as a sensitive method for the fractionation of volatile componentsof the essential oils.Principal component analysis was proposed as an exploratory chemometric methodfor the differentiation of essential oils from fruits at different degrees of ripening,taking into accountthe processes of production.Product-moment correlations between variables(concentrations of 17components)were used as starting matrices and the explained variance was adopted as a criterion foreigenvalue selection.Bi-plots and three-dimensional plots of unrotated principal component scores weresystematically used as well as those of orthogonally rotated factor scores.The 17 variables were reducedto four principal components,which explained 87% of the total variance.Projection on the first threeeigenvectors of all data as unrotated component scores allowed for a tentative differentiation of 59 oilsaccording to their degree of ripening.The two processes of production were also differentiated in asample of 55 oils. 相似文献
10.
典型黄土地貌类型区的地形复杂度分形研究 总被引：9，自引：0，他引：9
黄土高原地貌形态与地形复杂度自南向北有序变化,构成了举世瞩目的独特的地理景观。选择陕西省南北剖面六个典型黄土地貌样区为基本实验区,以其1∶1万栅格DEM为数据源,探讨典型黄土地貌类型区的地形复杂度分形与空间分异特征。首先提出的元分维模型方法,以计算得到的DEM元分维值作为特征指标,研究样区的地形复杂度问题。这种通过滑动窗口的扩展分维分析方法,既可以用于分析该区域不同尺度下的地形复杂度变化情况,也可以探讨区域的局部单元复杂程度及其空间分布,从而不再局限于对全区域的单一分维评价。以此为基础,进一步应用元分维谱方法,研究地貌网格单元的元分维分级分布情况。实验结果表明:以绥德和延川为代表的黄土峁状丘陵沟壑区最为复杂,以宜君和甘泉为代表的梁状丘陵沟壑区居中,而以淳化为代表的黄土塬区和以神木为代表的风沙黄土过渡区最为平缓。实验进一步证明了扩展分形方法在黄土地貌研究中的可行性。 相似文献
11.
Video observations of the underside of arctic sea ice-features and morphology on medium and small scales 总被引：2，自引：0，他引：2
Morphological structures and the occurrence of sea-ice sediments and ice-related algae at the ice floe-water column interface were studied by video observations in summer 1995. Recordings at twelve stations in the northern Laptev Sea and the adjacent Arctic Ocean showed large variations. On a medium-scale (metres), level ice and deformed floes as well as whole rafted and stacked floes were found. At the underside of floes, small-scale structures (centimetres such as bulges, depressions and holes were observed. The surface and sides of rafted floes sometimes had downward running grooves. Sediment inclusions occurred in diffuse or concentrated forms as well as in parallel streaks. Ice-related algae were visible as green areas at the underside of floes or as threads haniging into the water column. The distribution of sediments and algae was patchy. Some processes which might lead to the observed structures are suggested. 相似文献
12.
13.
区域旅游开发模式研究综述 总被引：6，自引：0，他引：6
近20年的时间里，区域旅游业开发经历了资源导向、市场导向、产品导向、形象导向等4个阶段。对以上4种开发模式的概念、特点、研究进展以及相互关系等问题进行综述、分析和评价，以便更深入更系统地研究区域旅游业开发模式的演化规律；不同区域旅游业的开发必须在综合分析区域旅游资源、旅游市场、旅游产品以及旅游形象等诸项特征的基础上，因地制宜地采取不同的开发模式； 相似文献
14.
川藏公路龙胆溪1#滑坡的演变 总被引：3，自引：0，他引：3
特大型滑坡如同其它事物一样经历着从发育、成长到灭亡以致循环往复的演变过程。本文从代表性的川藏公路龙胆溪特大型滑坡的发育机理研究出发,分别通过地质力学模型试验、数值计算、工程结构与滑坡的相互作用分析、大规模立体原位测试等多种手段,模拟、数据展现和结构调控了该滑坡的发育演变过程。为藏区的减灾环保和我国西部建设的发展作一些科学的储备。 相似文献
15.
L. M. Korytny 《Geography and Natural Resources》2017,38(2):111-121
The main development stages of the basin concept: from landscape hydrology to nature management are considered. It is shown that the river, lake and sea drainage basins are the most widespread natural complexes on and surface, with a high degree of integrity and with clear-cut watershed divides having a powerful integrating factor, the water flow. The substantiation is provided for the concepts of the basis as a geosystem, the runoff-producing complexes and the hydrological functions of landscape as well as for the principles of hydrological, water-resources and water-protection regionalization and zoning. On this basis, a classification of hazardous hydrological processes is developed. The structural patterns of the river network within the framework of structural geography are used for indication of the mean long-term discharge and its mapping, and for a classification of river systems according to their size. It is demonstrated that the integrating properties of the water flow permit the basin to be regarded as an integral system entity not only from the perspective of hydrology but also in terms of geomorphology, biogeocenology, landscape geochemistry as well as in complex physical geography as functionally integral natural complexes thereby creating the natural basis for nature management. On the other hand, many basins are socioeconomic and ethnodemographic entities. Ten principles are formulated for the theoretical justification of the basin concept of nature management where the basin is treated as an integral natural and economic system. It is suggested that such an approach should be used in governance of nature management, especially in international basins, as well as in reforming the system of administrative-territorial division of Russia. 相似文献
16.
高校旅游的开发模式及对策研究--以上海市高校旅游开发为例 总被引：5，自引：0，他引：5
在分析上海市高校旅游资源以及高校旅游客源市场特点的基础上,指出目前上海市高校旅游存在政校企合作的开发模式、高校自主开发模式、游客自发游览模式等3种开发模式.上海市高校旅游开发中存在的主要问题是尚未形成良好的开发氛围、缺乏市场化运作、旅游产品和旅游项目单一.最后提出上海市高校旅游的开发对策,包括转变观念、充分重视高校旅游、建立政府主导型多方合作的开发模式、丰富旅游产品的形式和内容、采取灵活多样的营销策略. 相似文献
17.
Estimates of the number of undiscovered deposits offer a unique perspective on the nation's undiscovered mineral resources. As part of the 1998 assessment of undiscovered deposits of gold, silver, copper, lead, and zinc, estimates of the number of deposits were made for 305 of the 447 permissive tracts delineated in 19 assessment regions of the country. By aggregating number of undiscovered deposits by deposit type and by assessment region, a picture of the nation's undiscovered resources has emerged. For the nation as a whole, the mean estimate for the number of undiscovered deposits is 950. There is a 90% chance there are at least 747 undiscovered deposits and a 10% chance there are as many as 1,160 undiscovered deposits. For Alaska, the mean estimate for the number of undiscovered deposits is 281. There is a 90% chance there are at least 168 undiscovered deposits and a 10% chance there are as many as 402 undiscovered deposits. Assuming that the majority of deposits used to create the grade and tonnage models that formed the basis for estimating the number of undiscovered deposits are significant deposits, there remain about as many undiscovered deposits as have already been discovered. Consideration of the number of undiscovered deposits as part of national assessments carried out on a recurring basis serves as a leading indicator of the nation's total mineral resources. 相似文献
18.
现象学着重关注人的经验问题。在绅士化失所研究领域里,当研究视角从关注物质空间转变为空间经验时,“生活世界”成为了基本的出发点,这体现为从“直接性失所”往“间接性失所”的转变。以列斐伏尔的“表征的空间”为基础,围绕象征要素对失所经验展开定性分析则成为主要的研究路径。以此方法论,对重庆市下浩历史文化社区经历绅士化凸显出的失所经验进行分析,发现：1）失所经验在社区原住民、移民与游客群体中具有不同的表现方式。原住民的失所经验体现为其世代传承地方要素的丧失,导致“存在内部性”的丧失;移民的失所经验表现为移情载体的消失,导致其自由生活方式的丧失;游客的失所经验体现为彻底商业化导致其寻根体验地的消亡。2）移民在社区中开展的文化商业活动起到了嫁接内部本真社会空间与外部消费空间的作用,导致本真“社会空间”被中产阶级消费空间所置换。 相似文献
19.
《Urban geography》2013,34(8):771-793
In this paper, I examine how urban entrepreneurs socially construct nature to promote tourism and growth. Using textual analyses and interviews, I study one state-sponsored booster in Tucson, Arizona as it sells the city as "natural" landscape. The literatures on entrepreneurialism and place promotion are replete with cities sold as culture and history, suburbs sold as the pastoral, or rural spaces sold as countryside. There is another alternative, however: a metropolis "themed" as pristine desert. In response, this paper offers two modest contributions. The first is a detailed study of place marketing in a scenery-obsessed city. Second, I consider the possible contradictions of selling a growing city with images of its desert periphery. Only by understanding the "eco-entrepreneurial city" might we better theorize the ironies of a Tucson sold as "Real. Natural. Arizona." 相似文献
20.
Particle size and sorting characteristics of sand in transport on the stoss slope of a small reversing dune 总被引：2，自引：0，他引：2
Studies of the particle size and sorting characteristics of sand on the stoss slope of a 6-m high reversing dune show that the sand in transport is generally finer and better sorted than surface sand at the same position on the slope. The sand in transport becomes coarser and more poorly sorted as wind speed and rates of mass transport increase toward the dune crest. These patterns reflect changes in the competence of the wind, which is capable of transporting larger grains and a wider range of grain sizes as its speed increases in space and time. Our field observations suggest that the particle size and sorting characteristics of surface sand are highly dependent on antecedent wind conditions and are not an invariant property of the dune, as is widely assumed. The wide range of particle sizes on the surface, as well as its change through time, also has important implications for modeling sediment transport on dunes. Transport thresholds may vary by as much as 30% on the stoss slope of the study dune. 相似文献