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561.
传统聚落文化景观基因的符号机制 总被引:3,自引:1,他引:2
传统聚落文化景观基因是解读传统聚落景观蕴含的深层次地学特征的重要切入点。然而该理论目前尚未从符号学的视角探索文化景观基因的符号机制。对此,本文首先从符号哲学的视角系统地分析了文化景观基因的特征:① 文化景观基因是宏观的聚落意象与微观的细节特征、物质外观表征与内在文化寓意、整体性特征与局部自我更新、定性与定量分析方法、优势性与内涵丰富性的辩证统一;② 文化景观基因有着多样的形态特征和复杂的空间结构,具有非线性、自组织和自迭代的重要特征。其次,论文探索了文化景观基因符号机制的概念,论述了文化景观基因的符号特征、分类和相应的表达方法,明确了构建文化景观基因符号的理论依据。最后,运用VC#.net程序语言开发了文化景观基因符号库原型程序,并给出了相应的实例。本文研究工作表明,开展文化景观基因符号机制的探索,对于完善传统聚落文化景观基因理论,促进文化景观基因资源的数字化等深化应用,具有重要的意义。 相似文献
562.
Development of a new index for integrating landscape patterns with ecological processes at watershed scale 总被引:12,自引:3,他引:9
Understanding the relationship between landscape patterns and ecological processes has been a central yet challenging research theme in landscape ecology. Over the past decades, many landscape metrics have been proposed but few directly incorporated ecological processes. In this paper, we developed a landscape index, namely, location-weighted landscape index (LWLI) to highlight the role of landscape type in ecological processes, such as nutrient losses and soil erosion. Within the framework of the Lorenz curve theory, we develop this index by integrating landscape pattern and point-based measurements at a watershed scale. The index can be used to characterize the contribution of landscape pattern to ecological processes (e.g. nutrient losses) with respect to a specific monitoring point in a watershed. Through a case study on nutrient losses in an agricultural area in northeastern China, we found that nutrient losses tended to be higher for a watershed with a higher LWLI value, and vice versa. It implied that LWLI can be used to evaluate the potential risk of nutrient losses or soil erosion by comparing their values across watersheds. In addition, this index can be extended to characterize ecological processes, such as the effect of landscape pattern on wildlife inhabitation and urban heat island effect. Finally, we discuss several problems that should be paid attention to when applying this index to a heterogeneous landscape site. 相似文献
563.
The spatial distribution of meteorological elements is important for understanding the regional meteorology and climate changes. However, previous studies rarely focused on the daily changes of the spatial patterns of meteorological elements due to the limitation of remote sensing (RS) techniques and traditional meteorological methods. In this paper, the regional meteorological elements were simulated by the fifth-generation non-hydrostatic Mesoscale Model (MM5), and the spatial patterns of meteorological elements and their diurnal variations were analyzed in landscape level over the Pearl (Zhujiang) River Delta (PRD), China. The results showed that there were several centers of urban heat islands, cold islands, dry islands, wet islands, high wind over the PRD at noon. The diurnal changes of Moran I of meteorological elements were obvious and they reached the extremum at noon and 2-3 hours after the sunrise. The landscape indices of meteorological elements, such as area-weighted mean Fractal Dimension Index (FRAC_AM), Landscape Shape Index (LSI), Shannon's Diversity Index (SHDI) and Contagion Index (CONTAG), were more variable at about the sunrise, noon and sunset. The occurrence of wave crests and vales of landscape indices was affected by the surface net radiation, turbulence and local circumfluence. The spatial patterns of meteorological elements correlated well with the land surface, thermal exchanges and local circumfluence. A new approach combining GIS, RS and numerical simulatious technologies and the landscape ecology method was presented to analyze spatial patterns of meteorological elements, which may be useful for studying global and regional climate changes. 相似文献
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566.
The goal of land consolidation in China is still to develop agricultural production. The study of landscapeeffects of land consolidation projects (LCPs) faces many difficulties because of the lack of government's interest anddata. This paper, taking Tianmen City of Hubei Province in Central China as an example, presents a methodology foranalyzing landscape effects of LCPs by GIS and Fragstats3.3. It describes landscape effects with indexes of PatchDensity (PD), Largest Patch Index (LPI), Landscape Shape Index (LSI), Interspersion and Juxtaposition Index (IJI),Aggregation Index (AI), and Shannon's Diversity Index (SHDI), showing more regular shape, simpler structure andless habitat diversity after LCPs. It computes ten landscape indexes of four categories of patches including CultivatedLand, Road, Water Channel, and River and Pond. The indexes show that 1) cultivated land becomes more fragmentalin patch area, less irregular in patch shape and more concentrated in block; 2) the transport capacity of roads and irri-gation and drainage capacity of water channels have been improved; 3) the landscape change of river and pond can besummarized as decreasing scale, more regular shape, reducing connectivity and diversity of the class. LCPs can facili-tate agricultural production as well as protect cultivated land and food security. However, it is doubted that the increaseof cultivated land from LCPs results from the reducing in landscape diversity of water area. 相似文献
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569.
景观格局与生态过程的耦合途径分析 总被引:20,自引:3,他引:20
景观生态学自诞生以来在理论和实践方面已经取得了众多进展, 然而在景观格局与生态 过程关系方面还有很多问题值得深入研究。本文阐述了景观格局和生态过程的有关概念和方法, 揭示了其中存在的一些问题和开展耦合研究的必要性, 进而总结了耦合研究的一般方法, 并在此 基础上提出了耦合研究的理论框架, 即以一定区域为依托和一定目标为导向进行土地单元或生 态系统类型划分, 通过土地评价和模型集成将小尺度观测研究和大尺度空间动态模拟相结合, 在 实现区域目标的基础上, 构建具有良好适应性的耦合模型系统。 相似文献
570.
借助1997年二类调查数据,在AreInfo的支持下,运用典范对应分析(CCA)法,对吉林省汪清林业局金沟岭林场的森林景观要素空间分布与环境关系进行了研究。结果表明:在金沟岭林场范围内,坡度和土层厚度对景观格局分布的影响极为有限,景观要素空间格局更多地受海拔和坡向综合控制,海拔是控制景观要素空间分布格局的主要因素,其次是坡向;森林景观总体分布是从河谷地低海拔榆杂林和杨桦林到高海拔红松云冷杉林;CCA排序图可将整个林场森林划分6组景观类型:榆树林景观、阔叶混交林景观、杨桦林景观、针阔混交林景观、阔叶红松林景观、人工纯林景观。 相似文献