This report summarizes the discovery of ca. 200 linear mounds along 40 km of the Des Moines River in central Iowa. Many of these mounds were mapped and recorded piecemeal over a century, but their ...full extents were not known until recent high-resolution lidar mapping. General insights about the age and significance of the mounds can be inferred from nearby archaeological sites and surface finds, as well as comparisons with regional mounds. Limited archaeological evidence suggests the linear mound concentration may be associated with a long stable Woodland occupation of the region, culminating in the Late Woodland Great Oasis manifestation.
For thousands of years, humans have altered the movement of water through construction of earthworks. These earthworks remain in landscapes, where they continue to alter hydrology, even where ...structures have long since been abandoned. Management of lands containing earthworks requires an understanding of how the earthworks impact hydrology and knowledge of where the structures are located in the landscape. Various methods for detecting topographic features exist in the literature, including a set of rule and threshold‐based techniques and machine learning methods. These tools are either labor‐intensive or require special pre‐processing or a priori assumptions about structures that limit generalizability. Here, we test a topological analysis tool called “persistence” to determine if it is useful for earthwork detection in rangelands. We found that persistence can be used to detect earthworks with 83% precision and 64% accuracy. Breached berms and berms with significant upslope sedimentation are most likely not to be detected using persistence. These results indicate that persistence can be useful for terrain analysis, and it has the potential to substantially reduce manual effort in feature detection by identifying regions where berms may be found.
Plain Language Summary
The shape of landscapes controls how water moves over the surface. Humans have modified landscapes by building earthen structures to direct water for thousands of years. The legacy of human water management systems remains in many places around the world, and land managers need to understand how these structures impact hydrology and where they are in order to support management decisions. Earthen dams, berms, and stock ponds dot the southwestern United States. High‐resolution elevation maps and imagery are increasingly available, and although man‐made structures are readily visible to the eye, automatic detection remains a challenge. In this study, a method from the mathematical field of topology called “persistence” was applied to automatically detect berms and stock ponds from elevation arrays. This method identifies features from a series of binary images generated from the same elevation map at consecutive threshold values. Results demonstrate that persistence is able to detect well‐defined berms. While not all berms are detected, these results are still promising since berms are generally found in groups. Thus, detection of even two thirds of the berms substantially narrows down regions for manual inspection.
Key Points
Persistent cohomology can be used to summarize topographic information
A persistence threshold is adequate to identify berms and stock ponds from focused regions
A set of criteria calculated from persistence can detect 64% of observed berms
In francese la parola “terril” indica delle colline artificiali composte da residui minerari formatesi in seguito all’attività estrattiva. I terrils costituiscono un paesaggio letteralmente ...collaterale, essendo il risultato, non del tutto atteso, di un’era industriale ormai estintasi e della quale essi ne rappresentano al contempo un residuo ma anche un monumento. Negli ultimi decenni diverse iniziative pubbliche e private hanno dimostrato come i terrils possano ritrovare un ruolo nel paesaggio e soprattutto come essi possano caricarsi di un nuovo significato. Episodi che raccontano di una graduale riappropriazione di questi luoghi, prima da parte delle popolazioni locali e in seguito dalla cultura di massa. Un lento processo che ha visto queste “colline” trasformarsi da stigmate di un passato del quale ci si voleva dimenticare, a paesaggi protetti dall’Unesco. / In French the word "terril" denominates artificial hills composed of mining residues that amass after extractions activities. The terrils literally constitute a collateral landscape, being the not entirely expected result of an extinct industrial age of which they simultaneously are a remnant and a monument. In recent decades, several public and private initiatives have shown how the terrils may find again a role in the landscape, particularly by charging them with new meanings. Episodes that narrate of a gradual re-appropriation of these places, first by the local population and ultimately also by mainstream culture. A slow process that has seen these "hills" transform themselves from a scar of a past we tried to forget, to UNESCO-protected landscapes.
Transportation geotechnics associated with constructing and maintaining properly functioning transportation infrastructure is a very resource intensive activity. Large amounts of materials and ...natural resources are required, consuming proportionately large amounts of energy and fuel. Thus, the implementation of the principles of sustainability is important to reduce energy consumption, carbon footprint, greenhouse gas emissions, and to increase material reuse/recycling, for example. This paper focusses on some issues and activities relevant to sustainable earthwork construction aimed at minimising the use of energy and the production of CO2 while improving the in-situ ground to enable its use as a foundation without the consumption of large amounts of primary aggregate as additional foundation layers. The use of recycled materials is discussed, including steel slag and tyre bales, alongside a conceptual framework for evaluating the utility of applications for recycled materials in transportation infrastructure.
Dedicated to an articulation of the earth from broadly ecological perspectives, eco art is a vibrant subset of contemporary art that addresses the widespread public concern with rapid climate change ...and related environmental issues. In Landscape into Eco Art , Mark Cheetham systematically examines connections and divergences between contemporary eco art, land art of the 1960s and 1970s, and the historical genre of landscape painting.
Through eight thematic case studies that illuminate what eco art means in practice, reception, and history, Cheetham places the form in a longer and broader art-historical context. He considers a wide range of media—from painting, sculpture, and photography to artists’ films, video, sound work, animation, and installation—and analyzes the work of internationally prominent artists such as Olafur Eliasson, Nancy Holt, Mark Dion, and Robert Smithson. In doing so, Cheetham reveals eco art to be a dynamic extension of a long tradition of landscape depiction in the West that boldly enters into today’s debates on climate science, government policy, and our collective and individual responsibility to the planet.
An ambitious intervention into eco-criticism and the environmental humanities, this volume provides original ways to understand the issues and practices of eco art in the Anthropocene. Art historians, humanities scholars, and lay readers interested in contemporary art and the environment will find Cheetham’s work valuable and invigorating.
Second Site Nisbet, James
2021, 20211130, 2021-11-16, Volume:
4
eBook
A meditation on how environmental change and the passage
of time transform the meaning of site-specific art In the
decades after World War II, artists and designers of the land art
movement used the ...natural landscape to create monumental
site-specific artworks. Second Site offers a powerful
meditation on how environmental change and the passage of time
alter and transform the meanings-and sometimes appearances-of works
created to inhabit a specific place. James Nisbet offers fresh
approaches to well-known artworks by Ant Farm, Rebecca Belmore,
Nancy Holt, Richard Serra, and Robert Smithson. He also examines
the work of less recognized artists such as Agnes Denes, Bonnie
Devine, and herman de vries. Nisbet tracks the vicissitudes wrought
by climate change and urban development on site-specific artworks,
taking readers from the plains of Amarillo, Texas, to a field of
volcanic rock in Mexico City, to abandoned quarries in Finland.
Providing vital perspectives on what it means to endure in an
ecologically volatile world, Second Site challenges
long-held beliefs about the permanency of site-based art, with
implications for the understanding and conservation of artistic
creation and cultural heritage.
Railway track support conditions affect ground-borne vibration generation and propagation. Therefore this paper presents a combined experimental and numerical study into high speed rail vibrations ...for tracks on three types of support: a cutting, an embankment and an at grade section. Firstly, an experimental campaign is undertaken where vibrations and in-situ soil properties are measured at three Belgian rail sites. A finite element model is then developed to recreate the complex ground topology at each site. A validation is performed and it is found that although the at-grade and embankment cases show a correlation with the experimental results, the cutting case is more challenging to replicate. Despite this, each site is then analysed to determine the effect of earthworks profile on ground vibrations, with both the near and far fields being investigated. It is found that different earthwork profiles generate strongly differing ground-borne vibration characteristics, with the embankment profile generating lower vibration levels in comparison to the cutting and at-grade cases. Therefore it is concluded that it is important to consider earthwork profiles when undertaking vibration assessments.
Display omitted
•Field experiments undertaken on 3 high speed lines with different track profiles.•A numerical prediction numerical model is is developed and validated for all the three cases.•Predicted at-grade vibration levels are most accurately reproduced.•Accuracy of predicted embankment vibration levels is shown to be acceptable.•Predicted cutting vibration levels are most challenging to reproduce.
At the construction site, the topography changes daily due to embankment and cut, and the amount of change is measured using surveying instruments to check the progress of construction. In the ...large-scale reconstruction work after the Great East Japan Earthquake, hundreds of thousands of cubic meters of earth and sand will be moved. In order to manage the process of such construction, we frequently and accurately grasp the progress with respect to the design soil volume. We used UAV photogrammetry to manage the progress of the construction site in order to accurately and easily measure the topographical changes at the construction site. In other words, by taking aerial photographs with the UAV and creating point cloud data by SfM / MVS processing, the accurate topography was grasped in a plane. By comparing the design data and the measurement data and finding the time-series change of the measurement data, it is possible to find the daily amount of earth and sand transported and the amount of work in the future. We confirmed the effectiveness of this method by applying it in the field. In addition, at such sites, the terrain will be rich in undulations as the construction of embankments and cuts progresses. Therefore, in order to keep the GSD of aerial photographs constant, we are also devising ways to control the flight altitude of the UAV. This method can be useful not only for construction work, but also for grasping changes in the ground surface after a landslide disaster and for subsequent restoration.
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