基于InSAR识别的黄土高原活动性地质灾害发育规律分析

地震、 降雨、 人类工程活动诱发的活动性地质灾害在黄土高原频现,但由于其地域广阔、 构造活跃、 地貌类型多样、 各地黄土特性差异较大,一直以来缺乏活动性地质灾害发育分布的系统认识.InSAR技术具有大范围观测地表变形的能力,文章利用2019年1月1日至2020年3月31日期间40期Sentinal-1 SAR数据,计算...     

Airborne laser scanning of forest resources: An overview of research in Italy as a commentary case study

This article reviews the recent literature concerning airborne laser scanning for forestry purposes in Italy, and presents the current methodologies used to extract forest characteristics from discrete return ALS (Airborne Laser Scanning) data. Increasing interest in ALS data is currently being shown, especially for remote sensing-based forest inventories in Italy; the driving force for this interest is the possibility of reducing costs and providing more accurate and efficient estimation of forest characteristics. This review covers a period of approximately ten years, from the first application of laser scanning for forestry purposes in 2003 to the present day, and shows that there are numerous ongoing research activities which use these technologies for the assessment of forest attributes (e.g., number of trees, mean tree height, stem volume) and ecological issues (e.g., gap identification, fuel model detection). The basic approaches – such as single tree detection and area-based modeling – have been widely examined and commented in order to explore the trend of methods in these technologies, including their applicability and performance. Finally this paper outlines and comments some of the common problems encountered in operational use of laser scanning in Italy, offering potentially useful guidelines and solutions for other countries with similar conditions, under a rather variable environmental framework comprising Alpine, temperate and Mediterranean forest ecosystems.     

A GIS-based glacier inventory for the Antarctic Peninsula and the South Shetland Islands —A first case study on King George Island

The aim of the international project “Global Land Ice Measurements from Space (GLIMS)” headed by the US Geological Survey is to establish a world wide glacier inventory based on satellite imagery. This data set will form a first digital baseline study for future glacier monitoring. The presented GIS-based glacier inventory for King George Island is a case study for the area of the Antarctic Peninsula. In the database of the glacier inventory topographic information, specific glaciological parameters as well as metadata will be included. The topographic data consists of drainage basin limits, basin areas, altitudinal ranges, perimeters and mean lengths. Glaciological data sets should comprise information on glacier retreat in different periods, glacier velocities, ice thickness and bedrock topography as well as derived parameters. Modelled and measured mass balance parameters could be included as additional data layers. In particular, these metadata records must comprise background information on data accuracy and data sources and should be compatible with a future data model for the King George Island GIS (KGIS). Three examples illustrate that the GLIMS database will not only contain information valuable for glaciological applications, but also other environmental studies on the island will benefit from this standardised remote sensing data sets. Therefore, a very close link between the data models of KGIS and GLIMS has to be established to enable these synergisms. Finally, better access to historic aerial photography would enable a continuous record of glacier retreat from the beginning of the 1950's onward.     

广西桂广滑石矿龙胜矿区新选厂2号滑坡分析与综合治理

文章从地层岩性、地质构造、水文地质条件等方面阐述该滑坡的基本特征,并对滑坡进行了稳定性分析与评价。根据滑坡特征及稳定性分析,提出采用预应力锚索、抗滑桩、挡土墙相结合的防治方案,具有较高的实践和理论意义。治理后经监测,未发生变形,处于稳定状态,表明该滑坡采用综合处治技术完全达到了预期,治理效果良好。     

云南省大关县滑坡灾害特征分析

介绍该县堆积面滑坡和层面滑坡两种典型滑坡的发育特征,分析其形成条件和机理.在此基础上,利用分形分维理论,分析研究区水系特征对滑坡分布和发育特征的影响.     

松江河石龙电站边坡加固工程施工技术

在松江河石龙电站边坡加固工程中,采用小直径抗滑桩加锚杆的桩锚联合支护体系,替代单纯的大直径抗滑桩,解决了陡峭边坡大型设备无法使用问题。采用潜孔锤跟管钻进工艺,解决了人工填石层钻孔坍塌及不能用水做循环介质的问题。介绍了该边坡治理方案及其施工技术,对陡峭边坡灾害治理工程有实用参考价值。     

南海北部神狐陆坡限制型滑塌体特征及成因机理

滑塌体是深水沉积的重要组成部分,研究滑塌体沉积有助于揭示深水沉积过程。利用高精度多道地震资料,首次在南海北部神狐陆坡段发现了规模逾千平方千米的限制型滑塌体,它在顺坡滑塌时,未能超越下坡地层的围限,突然终止于下坡未变形地层中,因此陡冲斜坡两侧的地震相特征发生截然的变化。滑塌体整体呈楔形,内部呈杂乱反射,前端存在逆冲断层以及挤压褶皱。由于顺坡滑塌距离较短,因此与非限制型滑塌体相比,限制型滑塌体内部地层连续性较好。结合神狐滑塌体地震反射特征并通过与世界典型滑塌体的对比,可知滑塌体的厚度、地形坡度二者共同控制了神狐滑塌体的发育类型,前端地形突起对其发育没有影响。     

降雨型浅层滑坡危险性预测模型

通过分析SHALSTAB和TRIGRS等浅层滑坡物理确定性模型存在的问题,提出了基于降雨入渗动态守恒的瞬态降雨入渗模型,该模型考虑了初期降雨过程、降雨历程以及饱和非饱和入渗过程,证明了SHALSTAB模型是该模型的特殊形式,并克服了TRIGRS模型参数繁多及一维入渗路径的问题.将无限边坡模型、瞬态降雨入渗模型和GIS进行耦合,研发了可用于大范围降雨型浅层滑坡危险性预测的集成系统,根据边坡的地质条件、地形参数和降雨特征即可对降雨条件下浅层滑坡的危险性进行评估.     

上海广粤路原垃圾堆场植被护坡探讨

上海虹口区广粤路垃圾堆场地处中心城区,是垃圾堆场改造成景的成功案例,但近年常受大暴雨影响发生小型滑坡。植被是经济和有效的水土保持和固坡方式。本文简述植被护坡机理与作用,针对广粤路垃圾堆场实际情况,探讨植被护坡的合理运用,以改善和提高城区环境面貌。     

基于SBAS/PS-InSAR技术的滑坡遥感监测对比研究

以2015~2019年12景ALOS-2 PALSAR2影像和2018~2019年38景Sentinel-1A影像为主要数据源,利用PS-InSAR和SBAS-InSAR技术提取西藏江达县波罗乡白格滑坡点的形变信息,并对处理结果进行交叉验证。研究得到以下结论：1）PS-InSAR技术条件下,ALOS-2数据和Sentinel-1A数据的平均形变速率范围为-68.9~37.9 mm/a和-64.5~24.2 mm/a;SBAS-InSAR技术条件下,ALOS-2数据和Sentinel-1A数据的平均形变速率范围为-84.2~-40.0 mm/a和-84.0~-13.0 mm/a。2）对2种数据结果中提取的4个特征点进行时序分析和定量分析显示,2种InSAR技术结果变化趋势较为一致,验证了两者在滑坡监测中的可靠性和准确性。