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101.
高山树线交错带的景观格局与生态过程   总被引:1,自引:1,他引:1  
由于对气候变化的敏感性, 近年来高山树线交错带成为全球变化研究中的热点问题。高 山树线交错带所指示的是一个复杂生态系统的特征, 反映出了由低处植被向高山植被的转化, 其 景观格局是综合了种子定居, 树木生长以及树木繁殖等多个树木生态过程和特定高山环境下的 地理特征格局的适应结果。一方面, 树木通过自身生理生态学上的调整对高山极端环境进行适 应。一方面, 高山特定地理环境特征对树线的景观格局进行影响, 因而高山树线交错带成为研究 景观格局- 生态过程相互关系的一个重要载体。通过运用3S 技术, 可以将高山树线交错带研究中 的树线景观结构和生理生态过程结合在一起, 并验证在其景观格局形成过程中地理特征和人为 因子的相对重要性。  相似文献   
102.
基于场所依赖的旅游地景观设计   总被引:1,自引:0,他引:1  
旅游地景观设计中,遵从自然、因地制宜、源于文化、考虑市场、适度设计、注重社区、人性设计等理念已深入人心。但事实上将这些理念付诸实践后,并没有很好地提高游客的回头率和忠诚度。因此,应将场所依赖理论作为一种新理念引入旅游地景观设计,从指导思想、前期调查、景观设计到整体评估全程运用该理论,以提高游客的重游率和忠诚度。  相似文献   
103.
国外景观地理学发展的回顾与展望   总被引:2,自引:0,他引:2  
在辨析景观的地理学及景观地理学的概念的基础上,总结了国外景观地理学发展的主要历程和成就,景观地理学的发展过程反映了人地关系的深化过程。通过对国外景观地理学发展的剖析,分析了其在研究领域及研究方法上的逐渐深化与完善,对新时期新问题下的景观地理学发展趋势及主要研究方向进行了展望。  相似文献   
104.
文化景观是人类活动的产物,文化景观研究是文化地理学的主要研究领域之一,而作为文化景观研究的重要组成部分的文化景观特性研究无疑将推动这一领域研究的进一步发展。运用比较分析方法,根据文化景观的定义,探讨文化景观具有时代性、继承性、叠加性、区域性、民族性等五大特性,并对这些特性进行科学的界定和详细的阐述,展示出这五大特性之间所存在的矛盾统一关系和其内在的紧密联系,进一步说明这些特性的实际意义和利用价值。  相似文献   
105.
利用2003年小江流域的TM影像,结合实地调查,再根据流域地质分布和地貌发育情况,将流域地貌类型划分为岩溶地貌和非岩溶地貌两个一级类型景观,在此基础上,根据地貌发育程度结合高程情况,将岩溶区又划分为6个岩溶景观,非岩溶地貌分为两个二级类型景观。应用景观生态学原理,并通过Fragstats 3.3软件在流域尺度上计算了一些相关指标。结果表明:岩溶区的景观生态特征总体上体现了其生态环境的特殊性和脆弱性,地表水资源溃乏,土层薄、土壤资源零星分布且易流失,造成未利用地面积大,石漠化现象严重,土地利用程度低的特点。非岩溶区景观生态由于耕地和林地占绝对优势,石漠化面积少,香农多样性指数和均匀度低,景观的异质性较低,结构较为简单。  相似文献   
106.
River regulation and river training have been performed for various purposes and negative effects have been shown in numerous cases. In some cases the negative effects are so serious that humans have to consider to "renaturalize" the regulated rivers. Only by using the strategy of integrated river management the diverse river uses and natural fluvial processes and ecological systems may be harmonized. Based on analysis of case studies and data collected from literatures this paper presents the concept of integrated river management and four principles of river training. The integrated river management comprises: 1) taking the watershed, upper stream basin including the tributaries, middle and lower reaches and the estuary as an integrated entity in the planning, design and management; and 2) mitigating or controlling the negative impacts on hydrology, erosion and sedimentation, fluvial processes, land use and river use, environment and ecology while in achieving economic benefit from water resources development, flood safety management and hydropower exploitation. River training and management should be in accordance with the four principles: 1) extending the duration of river water flowing on the continent, which may be achieved by extending the river course or reducing the flow velocity; 2) controlling various patterns of erosions and reducing the sediment transportation in the rivers; 3) increasing the diversity of habitat and enhancing the connectivity between the river and riparian waters; and 4) restoring natural landscapes.  相似文献   
107.
Research in landscape evolution over millions to tens of millions of years slowed considerably in the mid‐20th century, when Davisian and other approaches to geomorphology were replaced by functional, morphometric and ultimately process‐based approaches. Hack's scheme of dynamic equilibrium in landscape evolution was perhaps the major theoretical contribution to long‐term landscape evolution between the 1950s and about 1990, but it essentially ‘looked back’ to Davis for its springboard to a viewpoint contrary to that of Davis, as did less widely known schemes, such as Crickmay's hypothesis of unequal activity. Since about 1990, the field of long‐term landscape evolution has blossomed again, stimulated by the plate tectonics revolution and its re‐forging of the link between tectonics and topography, and by the development of numerical models that explore the links between tectonic processes and surface processes. This numerical modelling of landscape evolution has been built around formulation of bedrock river processes and slope processes, and has mostly focused on high‐elevation passive continental margins and convergent zones; these models now routinely include flexural and denudational isostasy. Major breakthroughs in analytical and geochronological techniques have been of profound relevance to all of the above. Low‐temperature thermochronology, and in particular apatite fission track analysis and (U–Th)/He analysis in apatite, have enabled rates of rock uplift and denudational exhumation from relatively shallow crustal depths (up to about 4 km) to be determined directly from, in effect, rock hand specimens. In a few situations, (U–Th)/He analysis has been used to determine the antiquity of major, long‐wavelength topography. Cosmogenic isotope analysis has enabled the determination of the ‘ages’ of bedrock and sedimentary surfaces, and/or the rates of denudation of these surfaces. These latter advances represent in some ways a ‘holy grail’ in geomorphology in that they enable determination of ‘dates and rates’ of geomorphological processes directly from rock surfaces. The increasing availability of analytical techniques such as cosmogenic isotope analysis should mean that much larger data sets become possible and lead to more sophisticated analyses, such as probability density functions (PDFs) of cosmogenic ages and even of cosmogenic isotope concentrations (CICs). PDFs of isotope concentrations must be a function of catchment area geomorphology (including tectonics) and it is at least theoretically possible to infer aspects of source area geomorphology and geomorphological processes from PDFs of CICs in sediments (‘detrital CICs’). Thus it may be possible to use PDFs of detrital CICs in basin sediments as a tool to infer aspects of the sediments' source area geomorphology and tectonics, complementing the standard sedimentological textural and compositional approaches to such issues. One of the most stimulating of recent conceptual advances has followed the considerations of the relationships between tectonics, climate and surface processes and especially the recognition of the importance of denudational isostasy in driving rock uplift (i.e. in driving tectonics and crustal processes). Attention has been focused very directly on surface processes and on the ways in which they may ‘drive’ rock uplift and thus even influence sub‐surface crustal conditions, such as pressure and temperature. Consequently, the broader geoscience communities are looking to geomorphologists to provide more detailed information on rates and processes of bedrock channel incision, as well as on catchment responses to such bedrock channel processes. More sophisticated numerical models of processes in bedrock channels and on their flanking hillslopes are required. In current numerical models of long‐term evolution of hillslopes and interfluves, for example, the simple dependency on slope of both the fluvial and hillslope components of these models means that a Davisian‐type of landscape evolution characterized by slope lowering is inevitably ‘confirmed’ by the models. In numerical modelling, the next advances will require better parameterized algorithms for hillslope processes, and more sophisticated formulations of bedrock channel incision processes, incorporating, for example, the effects of sediment shielding of the bed. Such increasing sophistication must be matched by careful assessment and testing of model outputs using pre‐established criteria and tests. Confirmation by these more sophisticated Davisian‐type numerical models of slope lowering under conditions of tectonic stability (no active rock uplift), and of constant slope angle and steady‐state landscape under conditions of ongoing rock uplift, will indicate that the Davis and Hack models are not mutually exclusive. A Hack‐type model (or a variant of it, incorporating slope adjustment to rock strength rather than to regolith strength) will apply to active settings where there is sufficient stream power and/or sediment flux for channels to incise at the rate of rock uplift. Post‐orogenic settings of decreased (or zero) active rock uplift would be characterized by a Davisian scheme of declining slope angles and non‐steady‐state (or transient) landscapes. Such post‐orogenic landscapes deserve much more attention than they have received of late, not least because the intriguing questions they pose about the preservation of ancient landscapes were hinted at in passing in the 1960s and have recently re‐surfaced. As we begin to ask again some of the grand questions that lay at the heart of geomorphology in its earliest days, large‐scale geomorphology is on the threshold of another ‘golden’ era to match that of the first half of the 20th century, when cyclical approaches underpinned virtually all geomorphological work. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
108.
景观生态学在城市规划和管理中的应用   总被引:53,自引:2,他引:53  
城市是典型的人工景观,空间结构上属于紧密汇聚型,功能上表现为高能流、高容量和文化上的多样性。城市景观生态研究包括城市空间结构与生态过程,城市景观风貌与城市生态建设,城市景观规划是其最直接的应用。首先论述了城市景观质量与价值评价,包括景观美学评价与景观视觉容量。城市空间结构和景观规划原则是该文论述的主题,包括城市空间布局、城市空间扩展的廊道效应以及城市绿地系统的空间结构分析;以上海和广州市的绿地系统为例进行了重点介绍,最后对于城乡交错带的景观变化进行分析,用景观格局及其动态来描述城乡交错带的城市化过程特点,介绍了上海和沈阳的典型研究。  相似文献   
109.
知识经济与传统的农业经济和工业经济显著不同,由它推动着的社会信息化及经济全球化所带来的地理发展效应,无论是在发展因素的加入上,还是在地域的建造上都愈来愈向着全息化的方向发展。与之相应,世界地理的研究范式,也应该向着更为开放、更为兼容化的方向改进。为此笔者提出全息景观论,并以韩国为例,以展示这种理论的科学解释价值。  相似文献   
110.
The spatial resolution of image data tends to constrain the horizontal length scale of genetic hypotheses that are addressable by those data. No ‘simple’ formula exists when image resolution is sufficient to test a given geomorphic process, which is dependent on what characteristics are diagnostic of the particular process. Genetic hypotheses should be formulated along the lines of the “multiple working hypotheses” concept as described in a classic paper by Chamberlin [J. Geol. 5 (1897) 837]. An essential element of a viable working hypothesis is a clear indication of the characteristics predicted by, or a consequence of, the hypothesis. An untestable hypothesis is not an effective working hypothesis. The history of the study of lunar sinuous rilles is outlined as an illustration of the influence of image resolution and the formulation of genetic hypotheses on the subsequent advancement of understanding of the problem. Sinuous rilles on Venus and Mars, and controversial sinuous ridges on Mars are also reviewed. In the lunar case, the three-order-of-magnitude improvement in spatial resolution provided by Lunar Orbiter photographs over Earth-based telescopic photographs did not result in definitive examination and elimination of published hypotheses for the formation of sinuous rilles. Topographic data obtained from cartographically controlled Apollo orbital photographs, along with important observations and samples obtained by the astronauts on the lunar surface, did test and exclude several hypotheses. The formulation of a genetic hypothesis, including testable consequences of that hypothesis, is a greater determinant of its ultimate utility to the scientific community than is the image resolution available at any given time.  相似文献   
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