32 research outputs found
GIS-based evaluation of diagnostic areas in landslide susceptibility analysis of Bahluieț River Basin (Moldavian Plateau, NE Romania). Are Neolithic sites in danger?
© 2018 Elsevier BV. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 24 month embargo from date of publication (April 2018) in accordance with the publisher’s archiving policy.The aim of this study is to compare the predictive strenghtness of different diagnostic areas in determining landslide susceptibility using frequency ratio (FR), statistical index (SI), and analytic hierarchy process (AHP) models in a catchment from the northeastern part of Romania. Scarps (point), landslide areas (polygon), and middle of the landslide (point) have been tested and checked in regards to their performance. The three statistical models have been employed to assess the landslide susceptibility using eleven conditioning factors (slope angle, elevation, curvature, lithology, precipitations, land use, topographic wetness index (TWI), landforms, aspect, plan curvature and distance to river). The three models were validated using the receiver operating characteristic (ROC) curves and the seed cell area index (SCAI) methods. The predictive capability of each model was established from the area under the curve (AUC), for FR, SI and AHP; the values are 0.75, 0.81 and 0.78 (using polygon as diagnostic area), respectively. Among the three methods used, SI had a better predictability. When it comes to the predictability values regarding the diagnostic areas, the landslide area (polygon) proves to have the highest values. This results from the entire surface of the landslide being taken into account when validating the data. Approximately 70% of the Neolithic sites are located in areas with high and very high susceptibility to landslides, meaning that they are in danger of being destroyed in the future. The final susceptibility maps are useful in hazard mitigation, risk reduction, a sustainable land use planning, evaluation of cultural heritage integrity, and to highlight the most endangered sites that are likely to be destroyed in the future
A glimpse into the northernmost thermo-erosion gullies in Svalbard archipelago and their implications for Arctic cultural heritage
First geophysical investigations to study a fragile Pomor cultural heritage site at Russekeila – Kapp Linné), Svalbard
With climate warming, the cultural heritage sites of the Arctic are in great danger. Extensive research is needed to study such sites. The archaeological site at Russekeila – Kapp Linné, Svalbard was selected for the survey as previous research had highlighted its vulnerability to cryospheric hazards. The main objectives of the survey were (i) to register the precise surface and subsurface locations of cultural heritage (CH) (remains of an 18th century Russian Pomor trapper's hut) objects within the study area, (ii) to determine the impact of coastal erosion on the CH objects and (iii) to understand the near-surface stratigraphy of the site. The geophysical surveys were carried out using a Ground Penetrating Radar (GPR) instrument with two shielded antennas of 500 MHz and 800 MHz centre frequencies. Only weak anomalies were observed at the intersections with wooden drifts, which can be explained by the low contrast between the relative dielectric constant values of the driftwood and the background soil. The depth extent of the driftwood within the soil was understood from the processed GPR data to a depth of approximately 25 cm. A near-surface stratigraphy of the site morphology, including thaw depth, saturated and unsaturated sediments and soil cover, was established based on multiple reflectors observed to 2 m depth. Loose sediments are indicated by reflectors to a depth of approximately 20 cm. Unsaturated fine sediments, which show a stronger signal compared to the underlying saturated sand layers, can be observed from about 1.2 m depth. No reflectors are shown below the thaw depth.First geophysical investigations to study a fragile Pomor cultural heritage site at Russekeila – Kapp Linné), SvalbardpublishedVersio
Is Overgrazing Really Influencing Soil Erosion?
Soil erosion is a serious problem spread over a variety of climatic areas around the world. The main purpose of this paper is to produce gully erosion susceptibility maps using different statistical models, such as frequency ratio (FR) and information value (IV), in a catchment from the northeastern part of Romania, covering a surface of 550 km2. In order to do so, a total number of 677 gullies were identified and randomly divided into training (80%) and validation (20%) datasets. In total, 10 conditioning factors were used to assess the gully susceptibility index (GSI); namely, elevation, precipitations, slope angle, curvature, lithology, drainage density, topographic wetness index, landforms, aspect, and distance from rivers. As a novelty, overgrazing was added as a conditioning factor. The final GSI maps were classified into four susceptibility classes: low, medium, high, and very high. In order to evaluate the two models prediction rate, the AUC (area under the curve) method was used. It has been observed that adding overgrazing as a contributing factor in calculating GSI does not considerably change the final output. Better predictability (0.87) and success rate (0.89) curves were obtained with the IV method, which proved to be more robust, unlike FR method, with 0.79 value for both predictability and success rate curves. When using sheepfolds, the value decreases by 0.01 in the case of the FR method, and by 0.02 in the case of the success rate curve for the IV method. However, this does not prove the fact that overgrazing is not influencing or accelerating soil erosion. A multi-temporal analysis of soil erosion is needed; this represents a future working hypothesis
Is digital shoreline analysis system “fit” for gully erosion assessment?
Gully erosion represents one of the most destructive geomorphological processes at a global level. Modern methods of gully erosion measurement are typically derived from earlier techniques that have since become outdated. The increasing capabilities of technology had led to new ways of quantifying soil erosion processes (e.g. gully erosion) which must be used in erosion assessment. A tool designed to assess coastal erosion – Digital Shoreline Analysis System (DSAS), is applied to the analysis of gully erosion. To assess the usefulness of this technique, three different types of gullies were chosen (dendritic, linear, and linear that became dendritic) from the Moldavian Plateau of Romania were chosen. Different parameters (SCE, EPR, NSM, and LRR) were tested and analysed. The best results were obtained in the case of dendritic gullies with specific adjustments to the processing values (smoothing distance set to >1000 and transect spacing at values >5 m). In the case of linear gullies, the smoothing distance needs to be set to lower values compared to dendritic gullies (1000) and transect spacing values >10 m. The average erosion rates obtained with the help of DSAS are very close to the ones from the literature of gully erosion on the Moldavian Plateau in Romania (over – 1.5 m/yr and under – 1 m/yr for gullies cut in sandy and clay deposits, respectively). This leads us to the conclusion that the DSAS tool is “fit” for gully erosion assessment. However, like any other software, it has limitations and possible disadvantages. The tool can be successfully used and applied in the field of soil erosion mitigation, disaster risk reduction, environmental and cultural heritage protection and in reaching the UNSDG
Photogrammetric Measurement of Erosion at the Sabbath Point Beothuk Site in Central Newfoundland, Canada
© 2020 by the authors. Erosion at archaeological sites in Central Newfoundland, Canada is a major concern, which is compounded by the fact that there has been a dearth of archaeological research in this region. While more than 70 house pits are known, very few excavations have examined whole features in the Exploits River Valley (ERV), and the archaeology of many has not been examined yet. The aim of this study is to examine the rate of erosion at the Sabbath Point house pit, a recently recorded archaeological site, located on the bank of Red Indian Lake (RIL), and to describe a low-cost methodology for analysing site level bank changes. This site is particularly important, as it represents an example of a late Beothuk residential feature about lifeways practiced in this region. The surveys employed here were carried out using image-based modelling. GRASS GIS was used to measure the diachronic difference between bank edges. The Digital Elevation Models (DEMs) were then compared, and the differences were measured using a transect based method. The erosion measurement has shown that Sabbath Point is in danger of being completely eroded. This shows that a salvage excavation program covering the entire feature is necessary within the next few years, as the feature itself will begin to erode
GIS-based Landform Classification of Eneolithic Archaeological Sites in the Plateau-plain Transition Zone (NE Romania): Habitation Practices vs. Flood Hazard Perception
The landforms of the Earth’s surface ranging from large-scale features to local topography are factors that influence human behavior in terms of habitation practices. The ability to extract geomorphological settings using geoinformatic techniques is an important aspect of any environmental analysis and archaeological landscape approach. Morphological data derived from DEMs with high accuracies (e.g., LiDAR data), can provide valuable information related to landscape modelling and landform classification processes. This study applies the first landform classification and flood hazard vulnerability of 730 Eneolithic (ca. 5000–3500 BCE) settlement locations within the plateau-plain transition zone of NE Romania. The classification was done using the SD (standard deviation) of TPI (Topographic Position Index) for the mean elevation (DEV) around each archaeological site, and HEC-RAS flood hazard pattern generated for 0.1% (1000 year) discharge insurance. The results indicate that prehistoric communities preferred to place their settlements for defensive purposes on hilltops, or in the close proximity of a steep slope. Based on flood hazard pattern, 8.2% out of the total sites had been placed in highly vulnerable areas. The results indicate an eco-cultural niche connected with habitation practices and flood hazard perception during the Eneolithic period in the plateau-plain transition zone of NE Romania and contribute to archaeological predictive modelling
Land use changes and dynamics over the last century around churches of Moldavia, Bukovina, Northern Romania – Challenges and future perspectives
In this study, the land use around the Churches of Moldavia, UNESCO WH (World Heritage) sites, has been analysed using photo interpretation and GIS. The cartographic analysis used historical maps and modern orthophotos to highlight the main changes that took place over the last century in the area surrounding the sites, which has been extended to 1 km buffer. Historical maps and orthophotos of the years 1917, 2005, and 2016 have been processed to identify the present and historical changes in one of the most well-known historical areas of Eastern Europe. Monuments have a significant universal, national, and local value, contributing to the touristic development of the area. The most important processes that can affect the integrity of the monuments are the deforestations and the anthropogenic environmental changes. Significant changes took place around Probota, Humor, Patrauti and Arbore churches, while Sucevita, Voronet and Moldovita churches still preserve the natural landscape specific to the Bukovina historical area; Suceava church is part of a strongly urbanised landscape
Climate change impacts on immovable cultural heritage in polar regions: A systematic bibliometric review
Over the past decade, research on the impacts of climate change on immovable cultural heritage (ICH) in the polar regions (Arctic and Antarctica) has slowly increased. This article offers a systematic review and synthesis of the publications about climate change impacts on the diverse ICH and climate change adaptation in the polar regions. Gray literature was not included in the study. Arctic countries like Sweden, Finland, Iceland, and Russia, and their associated research organizations, are under-represented in this literature when compared with the USA, Canada, Denmark, and Norway. More than half of the analyzed literature is published in the last 3 years (2019, 2020, and 2021) with a focus on coastal erosion and ICH degradation (cryospheric hazards). ICH is at risk from biological degradation, coastal erosion, debris flow, and thaw slumping. Nearly half of the studies report on the need for climate change adaptation planning and implementation for ICH. This study shows that advances in research on climate change impacts and adaptation responses are needed to improve decision- and policy-maker capacity to support effective adaptation policies and to contribute to the achievement of SDGs in polar regions. The polar regions' vulnerable landscapes and ICH sites can be used to communicate a larger message about the climate change challenges and adaptation measures. This article is categorized under: Assessing Impacts of Climate Change > Observed Impacts of Climate Change Vulnerability and Adaptation to Climate Change > Learning from Cases and Analogies Climate and Development > Sustainability and Human Well-Being.History & Complexit
Thaw slump inventory of Nordenskiöld Land (Svalbard Archipelago)
We present a comprehensive inventory of thaw slumps (landslides developed in the Arctic and sub-Arctic areas) in Nordenskiöld Land (Svalbard Archipelago). We used the most recent orthophotos (5 x 5 m pixel size) acquired in 2009-2011 from the Web Map Services (WMS) of the Norwegian Polar Institute. The thaw slumps were identified and digitised on-screen as polygons in the WGS_1984_UTM_Zone_33N coordinate reference system. We identified a number of 562 thaw slumps, that will be used along with the thermo-erosion gullies inventory to provide the first multi-hazard predictive model in the Arctic