[1] Lithology describes the geochemical, mineralogical, and physical properties of rocks. It plays a key role in many processes at the Earth surface, especially the fluxes of matter to soils, ecosystems, rivers, and oceans. Understanding these processes at the global scale requires a high resolution description of lithology. A new high resolution global lithological map (GLiM) was assembled from existing regional geological maps translated into lithological information with the help of regional literature. The GLiM represents the rock types of the Earth surface with 1,235,400 polygons. The lithological classification consists of three levels. The first level contains 16 lithological classes comparable to previously applied definitions in global lithological maps. The additional two levels contain 12 and 14 subclasses, respectively, which describe more specific rock attributes. According to the GLiM, the Earth is covered by 64% sediments (a third of which are carbonates), 13% metamorphics, 7% plutonics, and 6% volcanics, and 10% are covered by water or ice. The high resolution of the GLiM allows observation of regional lithological distributions which often vary from the global average. The GLiM enables regional analysis of Earth surface processes at global scales. A gridded version of the GLiM is available at the PANGEA Database (http://dx.doi.org/10.1594/PANGAEA.788537).

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2012GC004370

The new global lithological map database GLiM: A representation of rock properties at the Earth surface

Shallow landslides are a significant hazard in steep, soil-mantled landscapes. During intense rainfall events, the distribution of shallow landslides is controlled by variations in landscape gradient, the frictional and cohesive properties of soil and roots, and the subsurface hydrologic response. While gradients can be estimated from digital elevation models, information on soil and root properties remains sparse. We investigated whether geomorphically controlled variations in ecology affect the spatial distribution of root cohesion by measuring the distribution and tensile strength of roots from soil pits dug downslope of 15 native trees in the southern Appalachian Mountains, North Carolina, United States. Root tensile strengths from different hardwood tree species were similar and consistently higher than the only native shrub species measured (Rhododendron maximum). Roots were stronger in trees found on noses (areas of divergent topography) relative to those in hollows (unchanneled, convergent topography) coincident with the variability in cellulose content. This cellulose variability is likely related to topographic differences in soil water potential. For all species, roots were concentrated close to the soil surface, with roots in hollows being more evenly distributed in the soil column than those on noses. Trees located on noses had higher mean root cohesion than those in hollows because of a higher root tensile force. R. maximum had the shallowest, weakest roots suggesting that recent expansion of this species due to fire suppression has likely lowered the root cohesion of some hollows. Quantification of this feedback between physiologic controls on root growth and slope hydrology has allowed us to create a curvature-based model of root cohesion that is a significant improvement on current models that assume a spatially averaged value.

/pdf/topographic-and-ecologic-controls-on-root-reinforcement-51scdwd19m.pdf

Topographic and ecologic controls on root reinforcement

With the emergence and development of unmanned aerial vehicles (UAVs), different sensors have become more miniaturized and intelligent. UAVs equipped with various sensors are now an important approach for acquiring spatial data. Many advantages, such as low cost, short revisiting cycle, flexibility and high precision, have made UAVs powerful tools in geological, agricultural, ecological and forestry growth monitoring, as well as evaluation. Now, UAVs are a hotspot in scientific research. Their application in mining areas (MA), although still in its infancy, is developing rapidly in terms of speed, scale and service scope. This research examines aspects such as UAV platforms, different sensors and their application fields, as well as reviewing the advances of scientific research in MA at the present time. By combining current research and the functions of multiple sensors, an application framework for UAV monitoring in MA is constructed. Finally, the challenge and prospects for the development of UAVs and sensors are also considered. This research hopes to provide a technical reference, expanding the knowledge and recognition of UAV monitoring in MA, as well as an assessment of applications in mining, reclamation and environment.

/pdf/a-review-of-uav-monitoring-in-mining-areas-current-status-4vpximvkzq.pdf

A review of UAV monitoring in mining areas: current status and future perspectives

The increasing availability of remotely sensed data offers a new opportunity to address landslide hazard assessment at larger spatial scales. A prototype global satellite-based landslide hazard algorithm has been developed to identify areas that may experience landslide activity. This system combines a calculation of static landslide susceptibility with satellite-derived rainfall estimates and uses a threshold approach to generate a set of ‘nowcasts’ that classify potentially hazardous areas. A recent evaluation of this algorithm framework found that while this tool represents an important first step in larger-scale near real-time landslide hazard assessment efforts, it requires several modifications before it can be fully realized as an operational tool. This study draws upon a prior work’s recommendations to develop a new approach for considering landslide susceptibility and hazard at the regional scale. This case study calculates a regional susceptibility map using remotely sensed and in situ information and a database of landslides triggered by Hurricane Mitch in 1998 over four countries in Central America. The susceptibility map is evaluated with a regional rainfall intensity–duration triggering threshold and results are compared with the global algorithm framework for the same event. Evaluation of this regional system suggests that this empirically based approach provides one plausible way to approach some of the data and resolution issues identified in the global assessment. The presented methodology is straightforward to implement, improves upon the global approach, and allows for results to be transferable between regions. The results also highlight several remaining challenges, including the empirical nature of the algorithm framework and adequate information for algorithm validation. Conclusions suggest that integrating additional triggering factors such as soil moisture may help to improve algorithm performance accuracy. The regional algorithm scenario represents an important step forward in advancing regional and global-scale landslide hazard assessment.

/pdf/advances-in-landslide-nowcasting-evaluation-of-a-global-and-307t06z9ak.pdf

Advances in Landslide Nowcasting: Evaluation of a Global and Regional Modeling Approach

Diversity declines in Microstegium vimineum (Japanese stiltgrass) patches

For areas of the world that do not have access to lidar, fine-scale digital elevation models (DEMs) can be photogrammetrically created using globally available high-spatial resolution stereo satell...

Creating high-resolution bare-earth digital elevation models (DEMs) from stereo imagery in an area of densely vegetated deciduous forest using combinations of procedures designed for lidar point cloud filtering

Geology of the Chesapeake and Ohio Canal National Historical Park and Potomac River Corridor, District of Columbia, Maryland, West Virginia, and Virginia; A, Geologic map and GIS files (disc 1); B, Geologic report and figures (disc 2)

Multi-scale 46-year remote sensing change detection of diamond mining and land cover in a conflict and post-conflict setting

A sub-national scale geospatial analysis of diamond deposit lootability: The case of the Central African Republic

Increasing urbanization and suburban growth in cities globally has highlighted the importance of land planning using detailed geomorphologic maps that depict anthropogenic landform changes. Such ma...

https://www.tandfonline.com/doi/pdf/10.1080/17445647.2020.1746419

Geomorphological mapping and anthropogenic landform change in an urbanizing watershed using structure-from-motion photogrammetry and geospatial modeling techniques

Peter G. Chirico

Papers

Creating high-resolution bare-earth digital elevation models (DEMs) from stereo imagery in an area of densely vegetated deciduous forest using combinations of procedures designed for lidar point cloud filtering

Geology of the Chesapeake and Ohio Canal National Historical Park and Potomac River Corridor, District of Columbia, Maryland, West Virginia, and Virginia; A, Geologic map and GIS files (disc 1); B, Geologic report and figures (disc 2)

Multi-scale 46-year remote sensing change detection of diamond mining and land cover in a conflict and post-conflict setting

A sub-national scale geospatial analysis of diamond deposit lootability: The case of the Central African Republic

Geomorphological mapping and anthropogenic landform change in an urbanizing watershed using structure-from-motion photogrammetry and geospatial modeling techniques