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371.
针对传统的城市园林绿化资源调查方式的弊端,提出了城市园林绿化资源一体化调查的解决方案。详细介绍了一体化调查技术的总体思路和调查内容,探讨了一体化调查技术实现的关键技术和作业流程。通过实际应用,验证了一体化调查技术的合理性和可操作性,为各地园林信息化的建设提供了较好的参考和借鉴。 相似文献
372.
The paper examines the history of human interactions with the specific plateau and cuesta morphology developed upon Cretaceous sedimentary sequences in the Middle Sudetes, Central Europe (Poland, Czech Republic). Lithological contrasts influence relief at regional and local scale, providing diverse opportunities and limits to human activities since medieval times until the present. As a result a complex cultural landscape underpinned by geomorphology evolved through time, illustrating the concept of ‘sandstone phenomenon’. The following interactions with the physical landscape are identified: avoidance, adaptation, modification, and withdrawal. Although early modifications occurred in the late medieval period, adaptation rather than direct human impact typified the area until the mid-18th century. The expansion of settlement network in later times, along with forest clearance, development of quarrying and growth of tourism have led to substantial modifications of the geomorphological landscape and the origin of a suite of anthropic landforms. Depopulation of the region, particularly on the now Polish side, amplified after World War II, resulted in land use changes and renaturalization of many areas. Many previously occupied areas have been abandoned and various forms of nature and landscape protection now provide limitations to further development. Modification is tightly controlled, while re-adaptation is preferred and promoted, driven not by physical constraints anymore but by changing attitudes and increasing environmental awareness. 相似文献
373.
374.
福建泰宁世界地质公园丹霞红层研究 总被引:2,自引:0,他引:2
福建省泰宁世界地质公园以典型的年青期丹霞地貌为其地质特色,丹霞地貌由晚白垩世沙县组和崇安组红层构成。考察确认在金湖风洞一带的崇安组红层底部含较厚的流纹质火山岩夹层,这在福建全省境内是唯一的,从而为确定丹霞红层的准确时代提供了可能。研究表明,崇安组底部的火山岩由两次流纹质岩浆爆发性喷发形成,测得其锆石LAICP-MSU-Pb法年龄为98.52±0.96Ma,说明丹霞红层主体的形成时代为早、晚白垩世之交,而非以往认为的晚白垩世中—晚期,因此对华南丹霞红层的形成时代及其地质背景应重新审视,这一新认识对国内其他以丹霞地貌为特色的地质公园也同样有参考价值。 相似文献
375.
景观敏感度与阀值评价研究 总被引:33,自引:1,他引:33
景观敏戚度是景观被注意到的程度的量度,景观阀值是景观对外界干扰的抵御能力的量度,它们是风景旅游区景观保护规划的基本依据。以南太行山峡谷景观为例,文章探讨了景观敏感度和景观阀值的评价原理与方法,以及基于达两项评价的景观保护规划。 相似文献
376.
Relationships between landscape-scale geomorphology and aspects of the human environment (including heritage and material cultures) are best examined in landscapes with a strong geomorphological imprint of past climatic and environmental changes, and where human activity has been present for a long period of time. In Cornwall, southwest England, a strong geomorphological signature is imparted by weathering of granite bedrock under cold Quaternary climates, and a strong cultural and heritage imprint is manifested in material and nonmaterial ways through archaeology, art, literature and folklore, and is illustrated in this paper through examples of Bodmin Moor (north Cornwall) and West Penwith (west Cornwall). Landscapes of Bodmin Moor include wide valleys with underfit rivers and upland summits with prominent tors, resulting from granite weathering and slope processes during the Tertiary and Quaternary. Pollen records show how human activity has changed on the moor over time, with a peak of settlement during the Bronze Age, and expansion of grazing into the Iron Age. Daphne du Maurier's novels, set on or adjacent to Bodmin Moor, emphasize the moor's relationship to unstable and intense human emotions and crises. In West Penwith, which is geomorphological similar to Bodmin Moor, geomorphology–culture relations are demonstrated in different ways but through a similar sense of place and regional identity. The St Ives School of early 20th Century art, including the local artist Peter Lanyon and the sculptor Barbara Hepworth, draws inspiration from the local land and seascapes. The oral traditions and folklore of Zennor emphasize the importance of witchcraft and superstition that are in part founded on the wildness of upland summits and stormy coastline. Across West Penwith, tin mining and the mining trade exerted a strong impact on regional socioeconomic and cultural development from the Bronze Age until the end of the 19th Century, seen through settlement patterns, scientific innovation and Nonconformism. Today these geomorphology–culture relations are memorialized in the Cornwall and West Devon Mining Landscape World Heritage Site. 相似文献
377.
Kathleen C. Parker 《自然地理学》2013,34(4):322-335
Patterns of association of three columnar cactus species with potential nurse plants and rocks were examined in Organ Pipe Cactus National Monument, Arizona. Close spatial associates of cacti are often called “nurses” because they provide a less extreme microclimate for cactus seedlings, which improves survival rates. Of the three cacti, Carnegiea gigantea had the greatest frequency of association with nurse plants. Stenocereus thurberi, which is common on steep hillslopes where rocks and crevices offer numerous protected microsites for seedling establishment, was associated with nurse rocks more frequently than were the other two species. Lophocereus schottii showed the lowest frequency of association with nurses. In the Monument, L. schottii reproduces primarily through vegetative propagation, which reduces the need of small cacti for protection from nurses. Species most frequently associated with the three cacti were among the dominant species where each cactus occurred except that sparsely foliated species were associated with cacti less frequently than expected. This pattern supports previous claims that structural characteristics are more important than species identification in providing cacti with enhanced chances for survival. It also suggests that at a landscape scale, population dynamics of columnar cacti are more closely linked to patterns of overall vegetation change than to population fluctuations of a particular species that acts as a nurse. [Key words: northern Sonoran Desert, cactus establishment, nurse plants.] 相似文献
378.
STEPHEN WISE 《International journal of geographical information science》2013,27(2):111-120
Abstract The need for rapid access to large amounts of data is one of the central problems in the field of geographical information systems. This paper describes the use of a hardware solution to this problem, in the particular case of selecting digitized boundary data from a very large file. The hardware is International Computers'(ICL's) award winning Contents Addressable Filestore (CAFS) which is a special unit fitted to ICL disc drives allowing the fast selection of records from large files. By reformatting the boundary data, it was possible to perform searches using CAFS. A command-driven package was written to allow users to select the boundaries for any named zone or zones, display them on a graphics terminal and write them out in a format suitable for input to the GIMMS package. This package was tested on a file containing the boundaries of all the wards of Great Britain. After reformatting, this file was 6 Mbytes in size, but by means of CAFS could be searched interactively with response times of the order of 5-10 seconds. 相似文献
379.
Spatial contiguity is an important and fundamental landscape property in land allocation, habitat design, and forest management. The agreed upon notion of contiguity in the literature suggests shapelessness. However, existing approaches for measuring/promoting contiguity use proxies that either favour a particular shape or ignore inter‐patch relationships in fragmented landscapes. We propose an unbiased relative measure of contiguity ranging from zero to one based on graph theory and spatial interaction. The new measure reflects intra‐patch and inter‐patch relationships by quantifying contiguity within patches and potential contiguity among patches. Empirical analysis suggests that this measure of contiguity is reliable, consistent, and insensitive to sub‐region shape. 相似文献
380.
Morten Rasch Niels Nielsen Christian Christiansen Thomas Balstrøm Robert Gilbert Joseph Desloges 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):1-11
Measurements of discharge and suspended sediment and organic matter yield from nine different drainage basins on the island Disko in central West Greenland were carried out in the period 19–30 July 1997. A series of landscape properties (glacier cover, altitude, slope, aspect and vegetation cover) were measured for each drainage basin from a digital elevation model and a satellite image. Principal Component Analysis and regression statistics have been used to examine which landscape parameters dominate the measured discharges and yields. It is concluded that differences in suspended sediment and organic matter yield between the drainage basins can be explained by the measured morphometric properties while differences in water run-off can not. Glacier cover percentage and percent area above 800 m a.s.l. were the most important parameters influencing suspended sediment and organic matter yield in the drainage basins on Disko during the study period. 相似文献