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2021 ◽  
Vol 4 ◽  
pp. 1-8
Author(s):  
Jean-François Girres ◽  
Martine Assenat ◽  
Veysel Malıt

Abstract. The structure of the historical center of the city of Diyarbakır is largely inherited from the Roman city of Amida, through numerous testimonies still present in certain urban elements, such as buildings or cadastral parcels. The detailed analysis of the orientation of these urban elements in the current urban plan of Diyarbakır can contribute in particular to a better understanding of the different eras of foundation of the city of Amida and their spatial extensions. This research proposes to compare two methods of extraction of orientations from urban elements of the city of Diyarbakır. First, historians carried out a manual survey of the orientations from an aerial photograph, which made it possible to bring out two frames corresponding to two eras of the founding of the Roman city of Amida. These orientations were then compared with those extracted automatically from the geographic databases of cadastral parcels and built-up urban elements captured at a large scale. If the results obtained with the two methods converge, they also show differences, both on the orientation values and on the spatial extension of the two frames observed. These differences may contradict the initial observations, but are also sources of new perspectives of research on the spatial extension of the different periods of foundation of the Roman city of Amida. Finally, the results of this research tend to show that the two approaches prove to be complementary in detecting ancient urban structures in a contemporary city plan.


2021 ◽  
Vol 72 ◽  
pp. 177-190
Author(s):  
Afiq F.A. Rahim ◽  
◽  
Abd Rasid Jaapar ◽  
Zakaria Mohamad ◽  
◽  
...  

Relatively cool tropical climate with high annual rainfall experienced in mountainous tropical region creates favorable agricultural areas where intensive agricultural practices often correlate with increasing landslide events. While it has long been associated with landslides, agricultural practice in such areas especially in Cameron Highlands, Malaysia continues to flourish with minimal regard to environmental sustainability and safety. Therefore, this study aims to confirm the relationship between human activities and landslide occurrences and identify human practices that directly or indirectly cause landslides. Aerial photograph was used to identify landslides and anthropogenic features while other remotely sensed data including Interferometric Synthetic Aperture Radar (IFSAR) were used to establish the geomorphology of study area. A total of 207 landslides were identified in a 25 km2 area from remote sensing study and field mapping. They were superimposed over several potential contributing factors including geology, slope gradient and human activities. This study found that landslides are more likely to occur in areas greater than 15° of slope angle. The main factor, however, is the human factor where 164 landslides (79.22% of total identified landslides) were located in agricultural lands. Poorly planned and engineered agricultural farms were identified as the main causal factors for landslide occurrences at the study area, either directly or indirectly. These issues were observed through remote sensing study using aerial photograph which were then verified through site observations. New district development plan called for a stricter regulations in new tourism and agricultural developments. Improvements should also be implemented on existing agricultural activities where most of these landslides were located at this area. Therefore, in addition to controlling new developments, improving of existing agricultural practices in Cameron Highlands shall be a major focus in ensuring slope safety and their sustainability.


2021 ◽  
Author(s):  
◽  
David Olson

<p>Mixed Sand and Gravel (MSG) Beach research in recent decades has overwhelmingly focussed on open-oceanic environments, however, those found in fetch limited settings remain poorly understood. This thesis has examined spatial and temporal morphological change through such a system in Eastbourne, Wellington Harbour, New Zealand. This site has only recently prograded following several decades of erosion. This accretion has been the result of a northward migrating gravel front, which is introducing gravel sized sediment into the previously sandy system resulting in significant changes in beach morphology and volume. The aim of this study is to quantify these spatial and temporal changes and to assess shoreline stability on a decadal timescale. Additionally it aims to ascertain whether the current progradation is a long term change to the system or the result of a short term sediment increase. This assessment has been conducted in the form of topographic surveying, grain size and aerial photograph analysis. The topographic surveying and grain size analysis provides an accurate description of beach morphology. This is compared to the established MSG beach morphology models for the open coast, but operating on a smaller scale because of the lower energy fetch-limited environment of the study area. Aerial photograph analysis is used to show the longer term changes in beach width and the northern migration of the gravel fraction of the sediment supply regime. The spatial analysis results show that the beach morphology is highly variable. In the embayments that are more exposed to oceanic swell waves beach profiles are broad and steep, and in the beaches in the northern sections of the coastline which are more sheltered from oceanic swell waves, profiles are flat and narrow. The temporal results show that the coastal accretion observed through the study area has been initially rapid, followed by sustained increased beach width. These results suggest that the morphological variation on this coastline is part of a long term adjustment to a change in sediment supply, initiated by tectonic uplift and subsequently driven by longshore sediment transport. The observed mechanism of longshore transport has been suggested to be a function of sediment properties, relative wave energy and bathymetry/topography. The findings of this research are used to develop a conceptual model of shoreline evolution for the study area in response to changes that have occurred over the last 154 years.</p>


2021 ◽  
Author(s):  
◽  
David Olson

<p>Mixed Sand and Gravel (MSG) Beach research in recent decades has overwhelmingly focussed on open-oceanic environments, however, those found in fetch limited settings remain poorly understood. This thesis has examined spatial and temporal morphological change through such a system in Eastbourne, Wellington Harbour, New Zealand. This site has only recently prograded following several decades of erosion. This accretion has been the result of a northward migrating gravel front, which is introducing gravel sized sediment into the previously sandy system resulting in significant changes in beach morphology and volume. The aim of this study is to quantify these spatial and temporal changes and to assess shoreline stability on a decadal timescale. Additionally it aims to ascertain whether the current progradation is a long term change to the system or the result of a short term sediment increase. This assessment has been conducted in the form of topographic surveying, grain size and aerial photograph analysis. The topographic surveying and grain size analysis provides an accurate description of beach morphology. This is compared to the established MSG beach morphology models for the open coast, but operating on a smaller scale because of the lower energy fetch-limited environment of the study area. Aerial photograph analysis is used to show the longer term changes in beach width and the northern migration of the gravel fraction of the sediment supply regime. The spatial analysis results show that the beach morphology is highly variable. In the embayments that are more exposed to oceanic swell waves beach profiles are broad and steep, and in the beaches in the northern sections of the coastline which are more sheltered from oceanic swell waves, profiles are flat and narrow. The temporal results show that the coastal accretion observed through the study area has been initially rapid, followed by sustained increased beach width. These results suggest that the morphological variation on this coastline is part of a long term adjustment to a change in sediment supply, initiated by tectonic uplift and subsequently driven by longshore sediment transport. The observed mechanism of longshore transport has been suggested to be a function of sediment properties, relative wave energy and bathymetry/topography. The findings of this research are used to develop a conceptual model of shoreline evolution for the study area in response to changes that have occurred over the last 154 years.</p>


Author(s):  
Teresa Romão ◽  
António S. Câmara ◽  
Mathilde Molendijk ◽  
Henk Scholten

2021 ◽  
Vol 45 (1) ◽  
pp. 56
Author(s):  
Dwiko Budi Permadi ◽  
Nafiatul Umami ◽  
Ananto Triyogo ◽  
Rini Pujiarti ◽  
Bekti Larasati ◽  
...  

The successful rehabilitation of Wanagama teaching forests, which began in the late of 1960s, has created a distinctive forest ecosystem. Currently the forests become the habitat of Apis cerana, enterprised by the surrounding villagers to produce natural forest honey as a non-timber forest product. This paper aims to explore the adoption of smallholder beekeeping of A. cerana, the beekeepers’ socio-economic characteristics, the potential and value of forest honey production, the distribution of bee-boxes inside the forests and potential tree sources of nectar and pollen. Data collection was carried out in July - September 2019 with in-depth interview techniques to 38 beekeepers. Field observations and ground checks were carried out on the sites where beekeepers were placing the bee-boxes in the forest. In addition, an analysis of aerial photograph images taken with drone was also carried out to identify the area of trees as sources of nectar and pollen. The results show that between 1982 and 2019 the development of the adoption of the A. cerana beekeeping increased significantly. The total production of honey from 506 bee-boxes reached 658 liters or 894.9 kg in year of 2018/2019. The number of bee-boxes placed in Wanagama was mainly distributed inside Compartment of 13, 17, 14, 16, 5, and 18. Acacia mangium, eucalyptus, cajuput and mahogany were the main types of nectar-producing trees, in addition to the abundance of flowering undergrowth plants. Many of the challenges faced by honey beekeepers included climate change, the shortage of nectar and pollen sources, pests and diseases and human disturbances. This research suggests the need for a social, institutional and technical approaches to increase the forest productivity as sources of nectar and pollen. It is suggested encouraging the smallholders to adopt beekeeping as the main livelihood alternatives in future and planting more trees in Wanagama forests.


Author(s):  
Kei HIRASHIMA ◽  
Noritaka SHIGEI ◽  
Satoshi SUGIMOTO ◽  
Yoichi ISHIZUKA ◽  
Hiromi MIYAJIMA

2021 ◽  
Vol 8 ◽  
Author(s):  
Timothy A. Stahl ◽  
Nathan A. Niemi ◽  
Jaime E. Delano ◽  
Franklin D. Wolfe ◽  
Michael P. Bunds ◽  
...  

The Basin and Range province in the western United States hosts numerous low-slip-rate normal faults with diffuse and subtle surface expressions. Legacy aerial photographs, widely available across the region, can be used to generate high-resolution digital elevation models of these previously uncharacterized fault systems. Here, we test the limits and utility of aerial photograph-derived elevation products on the Drum Mountains fault zone—a virtually unstudied and enigmatic fault system in the eastern Basin and Range province of central Utah. We evaluate a new 2-m digital surface model produced from aerial photographs against other remotely sensed and field survey data and assess the various factors that contribute to noise, artifacts, and distortions. Despite some challenges, the new elevation model captures the complex array of cross-cutting fault scarps well. We demonstrate that the fault zone has variable net east- or west-down sense of displacement across a c. 8-km-wide zone of antithetic and synthetic traces. Optically stimulated luminescence ages and scarp profiles are used to constrain net extension rates across two transects and reveal that the Drum Mountains fault zone has average extension rates of c. 0.1–0.4 mm yr−1 over the last c. 35 ka. These rates are both faster than previously estimated and faster than most other faults in the region, and could be an order of magnitude higher if steep faults at the surface sole into a detachment at depth. Several models have been proposed for local and regional faulting at depth, but our data show that the offsets, rates, and geometries of faulting can be generated by the reactivation of pre-existing, cross-cutting faults in a structurally complex zone between other fault systems. This study highlights how legacy aerial-photograph-derived elevation products, in lieu of other high-resolution topographic datasets, can be used to study active faults, especially in remote regions where diffuse deformation would otherwise remain undetected.


2020 ◽  
Vol 6 (1) ◽  
pp. 417-433
Author(s):  
Vasiliki Lysandrou ◽  
Athos Agapiou

AbstractThis study deals with the investigation of the Eastern necropolis of Nea Paphos in western Cyprus, employing archival and recent aerial photographs for the identification of surface/near-surface ancient architectural remains. The analysis of the primary archival aerial photograph employed for this study reveals the archaeological visibility of the site as it had been captured approximately 15 years before its rescue excavation in the 1980s. The outcomes from the enhancement and interpretation of the archival aerial photograph supplement known archaeological information of the area and elucidate the understanding of the spatial distribution of the tombs as well as the geographic extent of the necropolis.


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