基于IMAGIS二维矢量数据的城市三维景观构建方法

研究了二维矢量数据在IMAGIS环境下,没有建模区DEM数据,利用等高线半自动赋值重新生成DEM和用等高线给山体建模构建城市三维景观的特殊方法。     

Assessing the effects of land use spatial structure on urban heat islands using HJ-1B remote sensing imagery in Wuhan,China

Urban heat islands (UHIs) have attracted attention around the world because they profoundly affect biological diversity and human life. Assessing the effects of the spatial structure of land use on UHIs is essential to better understanding and improving the ecological consequences of urbanization. This paper presents the radius fractal dimension to quantify the spatial variation of different land use types around the hot centers. By integrating remote sensing images from the newly launched HJ-1B satellite system, vegetation indexes, landscape metrics and fractal dimension, the effects of land use patterns on the urban thermal environment in Wuhan were comprehensively explored. The vegetation indexes and landscape metrics of the HJ-1B and other remote sensing satellites were compared and analyzed to validate the performance of the HJ-1B. The results have showed that land surface temperature (LST) is negatively related to only positive normalized difference vegetation index (NDVI) but to Fv across the entire range of values, which indicates that fractional vegetation (Fv) is an appropriate predictor of LST more than NDVI in forest areas. Furthermore, the mean LST is highly correlated with four class-based metrics and three landscape-based metrics, which suggests that the landscape composition and the spatial configuration both influence UHIs. All of them demonstrate that the HJ-1B satellite has a comparable capacity for UHI studies as other commonly used remote sensing satellites. The results of the fractal analysis show that the density of built-up areas sharply decreases from the hot centers to the edges of these areas, while the densities of water, forest and cropland increase. These relationships reveal that water, like forest and cropland, has a significant effect in mitigating UHIs in Wuhan due to its large spatial extent and homogeneous spatial distribution. These findings not only confirm the applicability and effectiveness of the HJ-1B satellite system for studying UHIs but also reveal the impacts of the spatial structure of land use on UHIs, which is helpful for improving the planning and management of the urban environment.     

Political memories of conflict,economic land concessions,and political landscapes in the Lao People’s Democratic Republic

Political memories—which are crucial for establishing and maintaining ‘political capital’, based on individual and group positioning during past conflict and wars, but also in relation to presentday politics—are important when considering varied outcomes from negotiations and other interactions that occur in the Lao People’s Democratic Republic in relation to large-scale economic land concessions. This paper continues to expand on the idea of political memories of past conflicts and wars by considering the concept in relation to the theoretical framework proposed by Hall et al. (2011) in their book Powers of Exclusion, which stresses the importance of interactions between regulation, force, the market and legitimation for understanding different types of exclusionary processes, especially those linked to land access. I argue that political memories are particularly relevant when it comes to legitimation, but that expanding the concept so as to include political memories is important. In relation to large-scale plantation, mining and hydropower dam concessions, I also stress the importance of political memories in (re)shaping understandings of landscapes, thus creating particular varieties of memory laden political landscapes, which too are constituted by the past but are also politically mobilized in the present.     

Holocene landscape evolution and geoarcheology of low-order streams in the Rio Grande basin,San Juan Mountains,Colorado, USA

This geoarcheological study investigates soil stratigraphy and geochronology of alluvial deposits to determine Holocene landscape evolution within the Hot Creek, La Jara Creek, and Alamosa River drainage basins in the San Juan Mountains of Colorado. Geomorphic mapping and radiocarbon dating indicate synchronicity in patterns of erosion, deposition, and stability between drainage basins. In all three basins, the maximum age of mapped alluvial terraces and fans is ~ 3300 cal yr BP. A depositional period seen at both Hot Creek and the Alamosa River begins ~ 3300 to 3200 cal yr BP. Based on soil development, short periods of stability followed by alluvial fan aggradation occur in the Alamosa River basin ~ 2200 cal yr BP. A period of landscape stability at Hot Creek before ~ 1100 cal yr BP is followed by a period of rapid aggradation within all three drainages between ~ 1100 and 850 cal yr BP. A final aggradation event occurred between ~ 630 and 520 cal yr BP at La Jara Creek. These patterns of landscape evolution over the past ~ 3300 yr provide the framework for an archeological model that predicts the potential for buried and surficial cultural materials in the research area.     

张掖丹霞暨彩色丘陵地质成因分析

利用实际调查测试资料和已有研究成果,在简述丹霞暨彩色丘陵区自然地理条件、地层构造及分布特征的基础上,全面阐述了祁连造山带前古生代、古生代—中生代地质构造发展变化过程。认为丹霞暨彩色丘陵成景地层大约形成于中生代末期100～140Ma BP前后的早白垩纪,沉积环境为河流—湖泊相红色及杂色层状碎屑岩沉积,总厚度大于5 000m。以青藏高原隆升为契机,宏观分析了新生代以来喜马拉雅、青藏、昆(仑山)黄(河)、共和4大构造运动及其由此引起的外动力条件的变化对丹霞暨彩色丘陵地貌各个阶段的演化并最终成型的影响和控制。认为喜马拉雅构造运动末期8Ma BP前后,隆升效应波及到祁连山区,成景地层受到挤压抬升和变形缩短,进而发生轻微褶曲并被长期风蚀、水侵及夷平;6～7Ma BP上新世,丹霞暨彩色丘陵地貌的雏形基本形成;昆(仑山)黄(河)运动结束后,大约0.2～0.4Ma BP中更新世,张掖丹霞暨彩色丘陵地貌已完全形成;共和运动期间丹霞暨彩色丘陵地貌区祁连山平均上升幅度为1.32～2.34mm/a。微观分析了幼年期、中年期、老年期及消亡期丹霞地貌的形成机理和外观特征;从沉积物Fe3+/Fe2+含量及当时环境下的氧化—还原程度诠释了彩色地层的形成原因。     

关于丹霞地貌概念和分类的探讨

现代丹霞地貌研究始于20世纪二、三十年代,地质学家冯景兰先生和陈国达教授是最早命名并进行丹霞地貌研究的科学家,也是从那时候丹霞地貌这一地貌术语正式由我国地学家首先命名和定义,但是对丹霞地貌概念的理解达数十种之多,各有侧重。本文基于大地构造运动和新构造运动的认识提出了典型和扩展丹霞地貌的概念和分类,在前人工作的基础上对丹霞地貌的准确定义和适用范围进行了进一步的研究和探讨。     

剑门关丹霞地貌晚侏罗—早白垩系沉积相的马尔科夫链特征

丹霞地貌是我国五大地貌之一,具有极大的科研和观赏价值。剑门关丹霞地貌具有年代新、类型多、分布较集中等特点,主要形成于侏罗—白垩纪,沉积岩层自下而上包括上侏罗统的遂宁组、莲花口组和下白垩统的剑门关组。根据沉积序列与旋回研究,将剑门关丹霞地貌沉积相划分为山麓-洪积扇、河流、湖泊、三角洲沉积相,运用马尔科夫链法建立丹霞地貌的沉积相序,形成沉积相模式,对研究剑门关丹霞地貌的古地理和古环境具有重要意义。     

城市湿地景观建设及原则

城市湿地是城市景观单元中最重要的近自然空间,在城市湿地景观建设中协调湿地的自然生态功能与经济、文化功能之间关系,是城市景观生态建设的重要内容,也是促进城市可持续发展的重要因素。本文在分析城市湿地生态功能的基础上,对比国内外在城市湿地景观建设实践上的差异,运用景观生态学原理,提出了城市湿地景观建设应该遵循的4个原则,即生态性、连续性和整体性、乡土性和美学的原则。     

龙虎山丹霞地貌"旅游景观价值-游客审美感知"探讨

通过对龙虎山丹霞地貌类型及其地质遗迹、人文景观的分析,按景区空间组合及代表性景观构建了旅游景观谱系。对这些景观进行评价和游客感知度调查,形成游客感知率与景观评价值矩阵,并用坐标法将矩阵划分为4个象限,分析其间的耦合性、差异性和产生机理。结果显示,总体上符合景观赋分值高、游客感知度高,景观赋分值低、游客感知度低的规律,但对一些典型地质遗迹,专家的评价与游客的感知度相差较大。游客仍以直观的山水审美为主,对其蕴含的科学性认知不够。地质遗迹科考产品和科普产品开发不足,尚未形成大众产品。比较不同游客群体的审美感知差异,为旅游产品的市场细分提供依据,并提出丹霞地貌景区建设建议。     

基于RS和GIS的阜阳市土地利用变化分析

以阜阳市区为研究对象,利用1987年、2000年和2009年的Landsat TM/ETM+遥感影像,结合GIS技术提取分析阜阳市区1987-2009年间土地利用动态变化信息。运用Fragstats3.3软件对研究区土地利用景观格局特征进行分析,在此基础上探讨其变化的驱动因素,为今后阜阳市区土地的可持续利用与城市发展规划提供了参考。