ISPRS International Journal of Geo-Information / Extraction of terraces on the loess plateau from high-resolution DEMs and imagery utilizing object-based image analysis

Terraces are typical artificial landforms on the Loess Plateau, with ecological functions in water and soil conservation, agricultural production, and biodiversity. Recording the spatial distribution of terraces is the basis of monitoring their extent and understanding their ecological effects. The current terrace extraction method mainly relies on high-resolution imagery, but its accuracy is limited due to vegetation coverage distorting the features of terraces in imagery. High-resolution topographic data reflecting the morphology of true terrace surfaces are needed. Terraces extraction on the Loess Plateau is challenging because of the complex terrain and diverse vegetation after the implementation of “vegetation recovery”. This study presents an automatic method of extracting terraces based on 1 m resolution digital elevation models (DEMs) and 0.3 m resolution Worldview-3 imagery as auxiliary information used for object-based image analysis (OBIA). A multi-resolution segmentation method was used where slope, positive and negative terrain index (PN), accumulative curvature slope (AC), and slope of slope (SOS) were determined as input layers for image segmentation by correlation analysis and Sheffield entropy method. The main classification features based on DEMs were chosen from the terrain features derived from terrain factors and texture features by gray-level co-occurrence matrix (GLCM) analysis; subsequently, these features were determined by the importance analysis on classification and regression tree (CART) analysis. Extraction rules based on DEMs were generated from the classification features with a total classification accuracy of 89.96%. The red band and near-infrared band of images were used to exclude construction land, which is easily confused with small-size terraces. As a result, the total classification accuracy was increased to 94%. The proposed method ensures comprehensive consideration of terrain, texture, shape, and spectrum characteristics, demonstrating huge potential in hilly-gully loess region with similarly complex terrain and diverse vegetation covers.(VLID)219512

Geomorphometry 2020. Conference Proceedings

Geomorphometry is the science of quantitative land surface analysis. It gathers various mathematical, statistical and image processing techniques to quantify morphological, hydrological, ecological and other aspects of a land surface. Common synonyms for geomorphometry are geomorphological analysis, terrain morphometry or terrain analysis and land surface analysis. The typical input to geomorphometric analysis is a square-grid representation of the land surface: a digital elevation (or land surface) model. The first Geomorphometry conference dates back to 2009 and it took place in Zürich, Switzerland. Subsequent events were in Redlands (California), Nánjīng (China), Poznan (Poland) and Boulder (Colorado), at about two years intervals. The International Society for Geomorphometry (ISG) and the Organizing Committee scheduled the sixth Geomorphometry conference in Perugia, Italy, June 2020. Worldwide safety measures dictated the event could not be held in presence, and we excluded the possibility to hold the conference remotely. Thus, we postponed the event by one year - it will be organized in June 2021, in Perugia, hosted by the Research Institute for Geo-Hydrological Protection of the Italian National Research Council (CNR IRPI) and the Department of Physics and Geology of the University of Perugia. One of the reasons why we postponed the conference, instead of canceling, was the encouraging number of submitted abstracts. Abstracts are actually short papers consisting of four pages, including figures and references, and they were peer-reviewed by the Scientific Committee of the conference. This book is a collection of the contributions revised by the authors after peer review. We grouped them in seven classes, as follows: • Data and methods (13 abstracts) • Geoheritage (6 abstracts) • Glacial processes (4 abstracts) • LIDAR and high resolution data (8 abstracts) • Morphotectonics (8 abstracts) • Natural hazards (12 abstracts) • Soil erosion and fluvial processes (16 abstracts) The 67 abstracts represent 80% of the initial contributions. The remaining ones were either not accepted after peer review or withdrawn by their Authors. Most of the contributions contain original material, and an extended version of a subset of them will be included in a special issue of a regular journal publication

Cartografía semi-automática de terrazas de cultivo a partir de datos LiDAR

The mountain systems surrounding the Mediterranean suffered a huge transformation related with the agriculture, mainly as a consequence of the agricultural terraces construction. These structures modify the topography and soils distribution, and, as a consequence, the drainage basins hydro-erosive dynamics. The massive land abandonment especially during the second half of the 20th century conduced to an afforestation associated with the occurrence of wild fires. The combination of fires and the collapse of the terraces walls has accelerated soil erosion processes. Actual sources of topographical data –mainly the airborne LiDAR- and the image analysis tools, offers an adequate resolution to get the land surface elements patters and map landforms such terrace steps. This paper explores the possibilities of such data sources and tools and pretends mapping the terrace walls both active and abandoned for the agricultural practices. Two small catchments have been selected in Mallorca and Castelló as samples characterised by the massive presence of agricultural terraces and using airborne LiDAR data has applied a procedure that produced satisfactory results. The maps have been check by means of photointerpretation and field work, and an exploratory work has been done analysing the influence of the terraces over the erosion processes by means of the study of the structural connectivity applying to the DTMs a Connectivity Index (IC)

Land-Surface Parameters for Spatial Predictive Mapping and Modeling

Land-surface parameters derived from digital land surface models (DLSMs) (for example, slope, surface curvature, topographic position, topographic roughness, aspect, heat load index, and topographic moisture index) can serve as key predictor variables in a wide variety of mapping and modeling tasks relating to geomorphic processes, landform delineation, ecological and habitat characterization, and geohazard, soil, wetland, and general thematic mapping and modeling. However, selecting features from the large number of potential derivatives that may be predictive for a specific feature or process can be complicated, and existing literature may offer contradictory or incomplete guidance. The availability of multiple data sources and the need to define moving window shapes, sizes, and cell weightings further complicate selecting and optimizing the feature space. This review focuses on the calculation and use of DLSM parameters for empirical spatial predictive modeling applications, which rely on training data and explanatory variables to make predictions of landscape features and processes over a defined geographic extent. The target audience for this review is researchers and analysts undertaking predictive modeling tasks that make use of the most widely used terrain variables. To outline best practices and highlight future research needs, we review a range of land-surface parameters relating to steepness, local relief, rugosity, slope orientation, solar insolation, and moisture and characterize their relationship to geomorphic processes. We then discuss important considerations when selecting such parameters for predictive mapping and modeling tasks to assist analysts in answering two critical questions: What landscape conditions or processes does a given measure characterize? How might a particular metric relate to the phenomenon or features being mapped, modeled, or studied? We recommend the use of landscape- and problem-specific pilot studies to answer, to the extent possible, these questions for potential features of interest in a mapping or modeling task. We describe existing techniques to reduce the size of the feature space using feature selection and feature reduction methods, assess the importance or contribution of specific metrics, and parameterize moving windows or characterize the landscape at varying scales using alternative methods while highlighting strengths, drawbacks, and knowledge gaps for specific techniques. Recent developments, such as explainable machine learning and convolutional neural network (CNN)-based deep learning, may guide and/or minimize the need for feature space engineering and ease the use of DLSMs in predictive modeling tasks

Remote Sensing of Natural Hazards

Each year, natural hazards such as earthquakes, cyclones, flooding, landslides, wildfires, avalanches, volcanic eruption, extreme temperatures, storm surges, drought, etc., result in widespread loss of life, livelihood, and critical infrastructure globally. With the unprecedented growth of the human population, largescale development activities, and changes to the natural environment, the frequency and intensity of extreme natural events and consequent impacts are expected to increase in the future.Technological interventions provide essential provisions for the prevention and mitigation of natural hazards. The data obtained through remote sensing systems with varied spatial, spectral, and temporal resolutions particularly provide prospects for furthering knowledge on spatiotemporal patterns and forecasting of natural hazards. The collection of data using earth observation systems has been valuable for alleviating the adverse effects of natural hazards, especially with their near real-time capabilities for tracking extreme natural events. Remote sensing systems from different platforms also serve as an important decision-support tool for devising response strategies, coordinating rescue operations, and making damage and loss estimations.With these in mind, this book seeks original contributions to the advanced applications of remote sensing and geographic information systems (GIS) techniques in understanding various dimensions of natural hazards through new theory, data products, and robust approaches

Young tectonic evolution of the Northern Alpine Foreland Basin, southern Germany, based on linking geomorphology and structural geology

The Northern Alpine Foreland Basin (NAFB) formed as a result of alpine continental collision in Oligocene time. Tectonic shortening has been slow since the Miocene, implying that the NAFB subsidence has come to rest. The scope of this thesis is to find evidence that yield information regarding the recent vertical tectonic activity and a potentially ongoing basin inversion. The identification of such an active inversion can be accomplished by studying the landscape evolution. This is possible, because the earth’s surface contains information about tectonic and erosional processes. In order to understand and quantify the underlying mechanisms forming the landscape, both surface and subsurface information can be linked. Especially when geophysical or similar data are insufficient, geomorphological analyses provide new insights. The NAFB is a low-strain sedimentary basin, where historic subsurface data confirm subsidence, while the present-day erosional relief indicates uplift. The basin has a long prospection history and geometries of basement faults are well known, but their link to topography is ambiguous and the landscape is regarded as climatically controlled. In this context, dense population and energy exploration call for a fundamental understanding, if the basin is uplifting and whether or not faults could potentially be reactivated. This thesis aims at characterizing geomorphotectonic indicators of uplift, potentially indicating NAFB inversion. Related to this process, vertical motion of a few hundred meters to a few kilometers is expected to have been taking place during the Plio- Pleistocene. My study addresses the Quaternary geomorphology and distribution of sediments across the NAFB. To assess a potential link between asymmetric valleys and underlying basement faults in the NE portion of the basin (Tertiary Hills region), I analyzed high-resolution space-borne imagery and carried out geologic fieldwork. Results in distinct geomorphological response of the NAFB are (a) regional scale erosion of sediments, (b) fluvial incision, (c) reactivation of documented faults and (d) regional scale tilting of paleo-geodetic markers. 1In the NE portion of the NAFB, the geometry of a detected high-angle geologic subsurface contact associated with a surface escarpment, potentially originated from young surface faulting, while landscape morphology is intensely overprinted by climatic processes and anthropogenic land use. The investigation of mid-Miocene coastal features of the Swabian Alb cliff line addresses the landscape evolution along the marginal area of the NAFB. The particular questions here are, if coastal outcrops are part of the same coast, and which mechanisms have caused their different present-day elevations. I investigated marine features in a geologic field survey and compiled stratigraphic data to infer the regional response to uplift. The results show that two sites represent temporally and spatially different coastal sections, and both have been intensely modified by multiple erosional processes. The data can be explained by invoking a combination of surface erosion and possible lithospheric scale uplift. My study of well data and geomorphic markers, to infer NAFB Quaternary sediment budgets, yields a remarkable erosion of sediments along the central E-W basin axis and fluvial networks in disequilibrium. I examined erosion rates across different timescales, using sediment yields from NAFB catchments and basin sediment flux. On the Pleistocene timescale, geomorphic indicators of fluvial systems are investigated while for the Holocene, archeological data provide constraints on local erosion. The results of this study reveal a distinct oval-shaped erosion pattern across the NAFB, which can explain the modern erosional relief of the region, and further implies active inversion of the basin. Similar results are derived from drainage pattern and river steepness estimates. The results of this thesis imply that the Quaternary landscape in the NAFB has been significantly influenced by tectonic activity. Further, the timing for the NAFB transition from subsidence to uplift is likely to originate at the Pliocene – Quaternary boundary, and continues. Therefore, the possibility of future fault reactivation, controlled by lithospheric scale uplift, cannot be ruled out

Young tectonic evolution of the Northern Alpine Foreland Basin, southern Germany, based on linking geomorphology and structural geology

The Northern Alpine Foreland Basin (NAFB) formed as a result of alpine continental collision in Oligocene time. Tectonic shortening has been slow since the Miocene, implying that the NAFB subsidence has come to rest. The scope of this thesis is to find evidence that yield information regarding the recent vertical tectonic activity and a potentially ongoing basin inversion. The identification of such an active inversion can be accomplished by studying the landscape evolution. This is possible, because the earth’s surface contains information about tectonic and erosional processes. In order to understand and quantify the underlying mechanisms forming the landscape, both surface and subsurface information can be linked. Especially when geophysical or similar data are insufficient, geomorphological analyses provide new insights. The NAFB is a low-strain sedimentary basin, where historic subsurface data confirm subsidence, while the present-day erosional relief indicates uplift. The basin has a long prospection history and geometries of basement faults are well known, but their link to topography is ambiguous and the landscape is regarded as climatically controlled. In this context, dense population and energy exploration call for a fundamental understanding, if the basin is uplifting and whether or not faults could potentially be reactivated. This thesis aims at characterizing geomorphotectonic indicators of uplift, potentially indicating NAFB inversion. Related to this process, vertical motion of a few hundred meters to a few kilometers is expected to have been taking place during the Plio- Pleistocene. My study addresses the Quaternary geomorphology and distribution of sediments across the NAFB. To assess a potential link between asymmetric valleys and underlying basement faults in the NE portion of the basin (Tertiary Hills region), I analyzed high-resolution space-borne imagery and carried out geologic fieldwork. Results in distinct geomorphological response of the NAFB are (a) regional scale erosion of sediments, (b) fluvial incision, (c) reactivation of documented faults and (d) regional scale tilting of paleo-geodetic markers. 1In the NE portion of the NAFB, the geometry of a detected high-angle geologic subsurface contact associated with a surface escarpment, potentially originated from young surface faulting, while landscape morphology is intensely overprinted by climatic processes and anthropogenic land use. The investigation of mid-Miocene coastal features of the Swabian Alb cliff line addresses the landscape evolution along the marginal area of the NAFB. The particular questions here are, if coastal outcrops are part of the same coast, and which mechanisms have caused their different present-day elevations. I investigated marine features in a geologic field survey and compiled stratigraphic data to infer the regional response to uplift. The results show that two sites represent temporally and spatially different coastal sections, and both have been intensely modified by multiple erosional processes. The data can be explained by invoking a combination of surface erosion and possible lithospheric scale uplift. My study of well data and geomorphic markers, to infer NAFB Quaternary sediment budgets, yields a remarkable erosion of sediments along the central E-W basin axis and fluvial networks in disequilibrium. I examined erosion rates across different timescales, using sediment yields from NAFB catchments and basin sediment flux. On the Pleistocene timescale, geomorphic indicators of fluvial systems are investigated while for the Holocene, archeological data provide constraints on local erosion. The results of this study reveal a distinct oval-shaped erosion pattern across the NAFB, which can explain the modern erosional relief of the region, and further implies active inversion of the basin. Similar results are derived from drainage pattern and river steepness estimates. The results of this thesis imply that the Quaternary landscape in the NAFB has been significantly influenced by tectonic activity. Further, the timing for the NAFB transition from subsidence to uplift is likely to originate at the Pliocene – Quaternary boundary, and continues. Therefore, the possibility of future fault reactivation, controlled by lithospheric scale uplift, cannot be ruled out

Rainwater Harvesting in Rural Jordan: A GIS and remote sensing-based analysis of ancient and modern adaptations to water scarcity in a changing environment

This study investigates the topic of rainwater harvesting on the Karak Plateau located in rural Jor-dan. The term rainwater harvesting describes various methods and structures employed for the collection, storage and use of rainwater and resulting (on-site) surface runoff. Within the scope of traditional water management, over millennia, many of these techniques were developed, refined and applied in Jordan, as well as in other, especially semiarid, regions of the world. This tradition is rooted in the natural water shortage of the plateau and frequent absence of other reliable sources of fresh water. Today, population growth, climate change and local effects of globalization and global change are leading to growing water shortages in the MENA region (Middle East and North Africa) and many other parts of the world. In the search for sustainable solutions for this problem, traditional as well as new strategies of rainwater harvesting have recently been receiving increasing interest. The present study contributes to an enhanced understanding of the applicability and the potential of some of the most widely-used, traditional rainwater harvesting methods, especially the use of cisterns. The mapped structures were examined taking into account the settlement history and the respective circumstances of the natural and human environment. Possible determining factors concerning site preferences and resulting patterns in the spatial distribution of rainwater harvesting sites have been detected. The diachronic comparative analysis revealed changes in human-environment-interactions, particularly with regard to the significance and management of local water resources under natural shortage. The collected data enabled the detailed estimation of the rainwater harvesting potential and the suggestion of possible ways to improve and expand current rainwater harvesting schemes and efforts. The integration and possible role of rainwater harvesting strategies were discussed with regard to modern, sustainable water management and supply. Additionally, the applicability of modern geoinformation techniques was evaluated. Remote sensing techniques and methods of image analysis, particularly with regard to the interpretation of satellite images of very high resolution, were examined especially. The combination of ground truth and other information from fieldwork and remote sensing-based data and techniques has proven most suitable and efficient. The mostly remote sensing-based mapping of rainwater harvesting structures and the establishment of a comprehensive database formed the basis for all subsequent analysis and possible further, sustainable planning steps. The semiautomatic analysis of the satellite imagery provided detailed information on land use/land cover and building rooftops and thus decisively contributed to the improvement of the (input) data basis. All in all, the collected data enabled a significantly enhanced, quantitative estimation of the rainwater harvesting potential of the study area. Many of the gained findings and insights can be transferred onto other dry areas and regions with similar environmental or socio-economic conditions

Comparison of Job Satisfaction Prediction Models for Construction Workers: CART vs. Neural Network

To establish a suitable prediction model of construction workers\u27 job satisfaction, this study chooses the widely used models CART (Classification and Regression Tree) and NN (Neural network) in the prediction model to make a comparison and finds out the main influencing factors of construction workers\u27 job satisfaction in occupational health and safety training. Through the investigation and analysis of 280 cases of empirical data, it is found that the CART model based on Kappa value and Accuracy of categorical variables have a better prediction effect, and the main factors affecting job satisfaction are job categories, working days per week and the latest training time. The main innovation of this paper is to add the actual value set of empirical data on the basis of the usual training set, verification set, test set and prediction set, and draw a conclusion by comparing the predicted value with the actual value of kappa