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71.
China has a vast area of mountains that are of great research interest. Chongqing is a typical mountain city in China. In urban construction, a mountain is not only an important limiting condition for urban development, but also an important condition for shaping the urban form. The area from the Yangtze River to the eastern ridge line of Nan Mountain in Nanan District is strongly representative of mountain cities with a complex landform, fragile ecological environment and a long history and culture. In recent years, the construction and optimization of this area are increasingly closely related to the landscape environment. However, due to the special environments of mountain cities, altitude and landform conditions become the key influencing conditions for further development of the cities. Therefore, this paper takes this region as an example, focuses on remote sensing and field measurement data, combines government data with that from scholarly research, and conducts relevant exploration through GIS, ENVI and some chart processing software. At first, from the perspective of the landscape gradient and urban construction, the characteristics of the urban landscape gradient are sorted out, and the developmental status of each urban area is analyzed. Then, the coupling relationships between the landscape features of each gradient and each urban area are analyzed. Finally, based on the analysis results, three major optimization measures are proposed to maintain ecological harmony in the mountainous area, reconstruct the mountain characteristic culture, and create unique mountain aesthetics, all with the hope of providing some guidance for the future development of the study area and similar mountain cities. 相似文献
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73.
A second‐generation, source‐to‐sink cellular automaton‐based model presented here captures and quantifies many of the factors controlling the evolution of aeolian dune‐field patterns by varying only a small number of parameters. The role of sediment supply, sediment availability and transport capacity (together defined as sediment state) in the development and evolution of an aeolian dune‐field pattern over long time scales is quantified from model simulations. Seven dune‐field patterns can be classified from simulation results varying the sediment supply and transport capacity that control the type and frequency of dune interactions, the sediment availability of the system and, ultimately, the development of dune‐field patterns. This model allows predictions to be made about the range of sediment supply and wind strengths required to produce the dune‐field patterns seen in the real world. A new clustered dune‐field pattern is identified from model results and used to propose an alternative mechanism for the formation of superimposed dunes. Bedforms are hypothesized to cluster together, simultaneously forming two spatial scales of bedforms without first developing a large basal dune with small superimposed dunes. Manipulation of boundary conditions produces evolving dune fields with different spatial configurations of sediment supply. Trends of spacing and crest length increase with decreasing variability as the dune field matures. This simple model is a valuable tool which can be used to elucidate the dominant control of aeolian sediment state on the construction and evolution of aeolian dune‐field patterns. 相似文献
74.
本文以济南市泉水补给区为研究对象,利用GIS空间分析方法,在其景观变化分析的基础上,参照中国陆地生态系统的生态服务价值系数,估算了泉水补给区生态服务功能价值变化,重点分析景观变化对研究区生态服务功能的影响,进而为区域可持续发展和城市建设提供理论支持。结果表明:(1)20世纪90年代以来,泉水补给区耕地和草地景观面积呈减少趋势,林地、园地和建设用地景观面积大幅增加,其中,以林地面积增加最大;从景观类型转化看,耕地与其他景观类型相互转化较为密切,特别是与建设用地和园地之间的转化;林地面积的增加主要来源于草地和耕地;(2)泉水补给区生态服务功能价值主要由林地和耕地景观生态服务价值构成,其变化对该研究区生态服务价值变化起决定作用;从生态服务价值构成类型来看,该地区土壤形成与保护服务功能单项价值所占比重最大,约占总服务功能价值的20%;(3)90年代以来,该地区总生态服务价值呈增加趋势;从单项服务价值变化来看,水源涵养、废物处理和食物生产服务功能价值则呈现出减小趋势,其中,以水源涵养减幅最大,为4.01%,主要是由该区建设用地增加,地面硬化面积增多而引起的。研究认为,济南市南部山区作为重要的泉水补给区,其生态服务功能尤为重要,特别是水源涵养功能,因此,研究区水源涵养服务功能价值的降低应在今后南部山区开发过程中得到足够的重视与保护,逐步增加泉水补给区的整体生态效益。 相似文献
75.
Landscape ecological construction and biodiversity protection 总被引:1,自引:0,他引:1
Landscapeecology,producedbyaGermannamedC.Trollin1939,wenttoresurrectioninthe1980safterhavingwaveredforoverfortyyears,andnowithasbeenanimportant,complicatedandcomprehensivecrossdiscipline.Inthe21stcentury,thesocialsustainabledevelopmentwillbethemajo… 相似文献
76.
77.
Saprolite Remnants as Indicators of Pre-Glacial Landform Genesis in Southeast Sweden 总被引:3,自引:0,他引:3
Mats Olvmo Karna Lidmar-Bergström Kerstin Ericson Johan M. Bonow 《Geografiska Annaler: Series A, Physical Geography》2005,87(3):447-460
Twenty‐six sites with remnants of gravelly saprolites (grus) have been located in southeast Sweden. Joint block hills (castle kopjes) and steep rock walls with weathered joints as well as rounded boulders are documented to have an origin in deep weathering and subsequent stripping of saprolites. The saprolite remnants and landforms result from the fragmentation of the re‐exposed sub‐Cambrian peneplain along fracture systems. Only shallow saprolites occur on the elevated intact parts of the sub‐Cambrian peneplain, while saprolites up to 20 m thick are encountered in areas where the sub‐Cambrian peneplain is fractured and dissected. Neogene uplift with reactivation of the weathering system is thought to be the main cause of saprolite formation. Deep weathering is thus judged to have been the major agent of landform formation in the study area, while glacial and glaciofluvial erosion has contributed mainly by stripping saprolites, detaching corestones, and plucking joint blocks along weathered joints. 相似文献
78.
国家风景名胜区景观遗产的三维培育研究--以青海湖为例 总被引:4,自引:0,他引:4
国家风景名胜区以其自然与人文美成为旅游与研究的热点。将国家风景名胜区的景观遗产划分为自然景观遗产、物质性历史文化遗产、非物质及口头文化遗产三维,并且探讨了景观遗产的培育理念。以青海湖国家风景名胜区为例,实证研究了其自然景观遗产的培育、物质性历史文化遗产的培育、非物质及口头文化遗产的培育。最后讨论了三个问题:对资源的重新认识、实证对其他案例的借鉴、三维培育模式的提取。 相似文献
79.
祁连山东段山地景观格局变化及其生态脆弱性分析 总被引:3,自引:1,他引:3
以RS和GIS技术为主要手段,分析了祁连山东段地区1994-2008年的景观格局变化及其生态脆弱性。结果表明:(1)与1994年相比,森林、草地、冰雪带、水域4种景观要素的面积分别减少了5.0%、2.0%、2.2%、2.0%,而灌木和裸地的面积则分别增加了6.8%、5.0%;灌木、草地、冰雪带和裸地景观要素的平均斑块面积分别增加了49.0%、19.0%、1.1%、436.6%,森林和水域平均斑块面积分别减小了9.6%和4.1%。(2)森林、草地、冰雪带、水域4种景观要素的平均最邻近距离增加,聚集度降低,各景观要素内部斑块之间聚集度减小。灌木与森林景观要素之间的空间邻接长度增加了3 867 km,裸地与其他景观要素之间的空间邻接长度增加了5 589 km,嵌缀在其他各种景观要素中的裸地小斑块逐渐融合成大斑块。(3)景观类型脆弱度指数与破碎度指数之间显著正相关,分维数倒数、分离度指数和沙化敏感性指数与景观类型脆弱度指数呈弱度正相关。祁连山东段地区森林和草地退化,面积萎缩、水域干涸,裸地面积增加,各景观要素的空间关系趋于简单,景观破碎化增加。人类活动所引起的景观破碎化是祁连山东段地区景观格局和景观脆弱性变化的决定性因素。 相似文献
80.
The cartography of land covers was used to study fertility and soil evolution in a mountainous Mediterranean area during the anthropocene period ( Crutzen P J 2002 Geology of mankind Nature 415 23). The aim was to determine changes in fertility as agricultural lands were abandoned in the 14 000 hectare area that constitutes Sant Llorenç del Munt Natural Park in a pre-coastal Catalan mountain range (north-eastern Iberian Peninsula). The analysis of land covers using vegetation maps, orthorectified images and aerial photography has allowed us to differentiate six vegetation groups: holm-oak wood, pine grove, oak wood, scrub, active agricultural fields and abandoned agricultural fields. The anthropic covers over the past 100 years were subdivided into five categories: active fields and those abandoned over four time periods. Study variables include field shape (concave, convex, flat), orientation (north, south) and slope (ranging from 12º to 24º). The parameters used for the physical-chemical soil analysis included organic material, phosphorous and potassium; fertility was classified based on groups, types and classes. The results indicate that even when the visual appearance of certain landscapes is similar, the edaphic characteristics may be very different. Changes induced by human disturbance share this phenomenon. Therefore, land management should be considered globally, taking into account vegetation, soils and water as interdependent factors, since it is their interaction that produces landscape and most affects its evolution over time. 相似文献