基于系统保护规划理论的广西海域优先保护格局分析     

李潇  刘昭阳  王晓莉  吴玥  左国成  陶以军 《海洋通报》2021,40(2):189-197

基于广西海域红树林、珊瑚礁、海草床等生境数据,在系统保护规划理论框架下,利用Marxan软件构建了广西海域优先保护格局以识别保护空缺.结果 表明:广西海域优先保护区集中在三娘湾、合浦、涠洲岛海域,部分区域游离在现有保护体系外.与广西海洋生态红线对比,保护空缺主要分布在沿岸滩涂分布区、红树林分布区和涠洲岛珊瑚礁分布区.本...  相似文献   

湛江市区环境地质问题及其防治对策   总被引：1，自引：0，他引：1  

罗树文  张林生 《地质灾害与环境保护》2006,17(3):10-13

湛江市区主要有崩(坍)塌、滑坡、地面沉降、地裂缝、环境水污染、水土流失、膨胀土地基变形、软土地基变形、土地沙化、风暴潮和港口淤积等环境地质问题,其形成与发展固然与自然地质环境相关,但基础设施建设、经济建设和较大规模的资源开发等人类工程活动是其主要控制因素。环境地质问题制约了该市地方经济和社会的可持续发展步伐,也为此而付出了较大的代价。这些环境地质问题均可通过有效的防治措施避免、减轻或得以治理,从而恢复其良好的生态环境。  相似文献   

A building label placement method for 3D visualizations based on candidate label evaluation and selection     

Jiangfeng She  Xinchi Li  Yaqian Chen  Junzhong Tan 《International journal of geographical information science》2019,33(10):2033-2054

Adding building labels greatly improves the recognizability of buildings and the readability of three-dimensional (3D) city scenes. However, building label placement is much more complex in 3D scenes than in two-dimensional (2D) maps. The annotation effect is influenced by the attributes of the 3D label, building visibility, and the spatial relationship between the building and viewpoint. In this context, automatically generating building labels for 3D scenes during interactions requires highly complex computations. By contrast, evaluating candidate labels and then selecting the suitable label for each building can be effectively implemented. This paper introduces an approach for labeling buildings in 3D scenes based on evaluations of label candidates. The proposed method predefines a candidate label set for each building. These candidates are then evaluated in terms of their attributes and the relationship between the labels and viewpoint at runtime. The best candidate label, or a situational alternative for each building, is then placed in order of comprehensive label priority to avoid annotation conflicts. A series of experiments demonstrate that this method effectively enhances the correlation of labels and buildings, improves interactive efficiency, and realizes a viable global label layout.  相似文献   

模糊层次分析法在山区大农业发展决策中的应用     

尹东 《山地学报》2005,23(3):348-352

采用模糊层次分析方法,综合考虑自然资源条件和市场需求,分析并提出陇南山区白龙江流域各垂直气候层中农业各部门的优先发展顺序,为山区大农业发展提供决策依据。  相似文献   

一种自适应快速曝光控制方法   总被引：2，自引：0，他引：2  

王雷斌  张爱武  叶泽田  侯明辉  曲文乾 《测绘科学》2009,34(2)

针对在快速运动中连续高速地获取高质量的图像信息,提出了一种基于光圈优先的自动曝光控制方法。通过对初始图像的评估,确定当前景物亮度下最佳光圈大小,进而获得此光圈下不同景物亮度的曝光时间,由此建立景物亮度与曝光时间的关系模型。在实际运用中根据关系模型,通过跟踪当前景物亮度动态调整曝光时间以达到获取最佳曝光量的目的。该方法具有实时、快速、成像质量高和控制精确可靠的特点,并在实际应用中得到验证。  相似文献   

自动综合算法库的构建     

钱海忠 《测绘科学》2009,34(6)

要提高自动综合的自动化水平,不但要开发自动化、智能化程度高的自动综合算法,同时需要对自动综合算法进行有效地管理和使用。目前国内外研究重点在于前者,而对后者研究较少。本文提出了自动综合算法元数据的概念,并从自动综合算法的适用范围、算法功能、算法参数等关键信息,以及算法基本信息、经验信息、改进信息和综合评价指标等辅助信息,以及自动综合算法优先权等方面着手,分步骤、分层次地设计并构建了自动综合算法的元数据管理体系,从而实现了方便、有效地管理与调用自动综合算法,为提高自动综合的自动化程度和水平提供了有力支持。  相似文献   

陆面过程研究的现状与发展趋势   总被引：25，自引：4，他引：25  

牛国跌  洪钟祥 《地球科学进展》1997,12(1):20-25

对目前陆面过程研究的现状及存在的问题进行了总结,并且提出了与边界层研究有关的几个前沿方向:①非均匀下垫面地表湍流通量的参数化及中尺度通量的参数化方法;②边界层理论在复杂地形条件下的应用,以及次网格地形对通量输送的影响;③进一步改进GCM中冠层地表水文参数化;④边界层的层云和层积云的参数化。  相似文献   

遥感尺度问题研究进展   总被引：56，自引：3，他引：56  

苏理宏  李小文  黄裕霞 《地球科学进展》2001,16(4):544-548

尺度是与空间现象有关的术语，在地学研究中更是一个重要的概念，忽视遥感观测的尺度效应，使得对地观测难以获得精确的地表参数，这一问题已经引起国际遥感界的重视，遥感物理建模和遥感数据应用都有尺度问题，像元尺度上地表参数的定量描述是建立遥感尺度转换模型和信息转换模型的基础，试图从尺度的定义，遥感尺度问题所涉及的内容和遥感尺度效应研究常用的技术方法等三个方面论述遥感尺度问题的研究进展，像元尺度上地表参数的定量描述是遥感信息尺度转换的基础。  相似文献   

A review of the ecohydrology discipline: Progress,challenges, and future directions in China     

XIA Jun  ZHANG Yongyong  MU Xingmin  ZUO Qiting  ZHOU Yujian  ZHAO Guangju 《地理学报(英文版)》2021,31(8):1085-1101

In recent decades,the ecohydrology discipline was developed to provide theoretical and technical foundations for the protection and restoration of complex ecological systems(e.g.,mountains,rivers,forests,farmlands,and lakes),and to further ecological civilization construction and green development in China.In this study,the progress and challenges of the ecohydrology discipline are elaborated,and the future development directions are pro-posed according to international scientific frontiers and national ecological civilization con-struction demands.Overall,the main discipline directions are to develop new ecohydrological monitoring methods,to comprehensively understand ecohydrological mechanisms and their basic theories,to promote integration of multi-scale and multi-variable models by considering both terrestrial and aquatic ecosystems,and to encourage multidisciplinary integration,par-ticularly with the social sciences.Furthermore,the future research interests in China include:combining multi-source information,constructing comprehensive monitoring systems,study-ing spatiotemporal patterns of key ecohydrological variables and their variation characteris-tics,developing integrated models of ecological,hydrological,and economic processes,es-timating their uncertainty;and conducting interdisciplinary studies that include the natural and social sciences.The application prospects in China are further explored for a variety of eco-systems,including forests,grasslands,rivers,lakes,wetlands,farmlands,and cities.This study will provide a reference to support the development of the ecohydrology discipline in China,and will provide a solid theoretical and technical foundation for the implementation of national ecological civilization construction.  相似文献   

Strategies of Successful Anti-Dam Movements: Evidence from Myanmar and Thailand     

Julian Kirchherr 《社会与自然资源》2018,31(2):166-182

Scholars are rarely able to examine anti-dam movements that result in project suspensions or cancellations since these cases are rare empirically. Yet, they are central to understanding how anti-dam movements can succeed. This paper analyzes the movements against Myanmar’s Myitsone Dam and Thailand’s Kaeng Suea Ten Dam. Likely the most successful anti-dam movements in Southeast Asia in recent years, they achieved suspension over 6 and 37 years, respectively. The research is based on 60 semistructured interviews carried out over a period of 8 months. Leveraging thinking from both the constructionist and structural schools within the field of social movement studies, it is found that the framing of the Myitsone Dam as a project threatening the national cultural heritage of Myanmar (in combination with political change in the country in 2010/2011) largely explains the movement’s success. Meanwhile, the set of sophisticated tactics (including inter alia demonstrations, Thai Baan research, 24/7 monitoring of the dam site, and spiritual activities) was decisive for the efficacy of the movement against Thailand’s Kaeng Suea Ten Dam.  相似文献