scholarly journals Shrinkage of the tarns in the High Tatras (Slovakia, Poland)

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Juraj Kapista ◽  
František Petrovič ◽  
Juraj HREŠKO ◽  
Zofia RĄCZKOWSKA

This paper assesses the shrinkage of glacial lakes in the High Tatras by analysing the series of historical and actual orthophotomaps from 1949 to 2018. The shoreline dynamics during this period were established by detailed retrospective remote sensing, and the decrease in the former surface of the water was caused by intensive interaction between morphodynamic processes and the lake basins. Herein, we have identified 38 tarns with an assumed decline in the area. This assumption was based on a comparison of initial visual analysis of the historical aerial photographs and the current orthophotomaps which capture all High Tatras tarns. We selected ten tarns with the largest or most representative changes and performed detailed cartographic analysis on them. We also attempted this analysis over shorter periods whenever possible and herein we established from 2.5 to 32.2% decrease in lake water surface area during the monitored period. This decrease in shallow lake basins was accompanied by the presence of accumulated debris flows, fine fraction fluvial-proluvial deposits, and vegetation. The shallow glacial lake basins are sensitive indicators of irreversible changes in their catchment areas and this study, therefore, highlights the effectiveness of combining detailed orthophotomaps and historical aerial photos and GIS tools in researching glacial lakes shoreline dynamics in the alpine landscape. Retrospective shoreline analysis facilitates the assessment of the effects of morphodynamic processes on the development of tarns from the postglacial period until today.

Author(s):  
Adam Choiński ◽  
Mariusz Ptak ◽  
Agnieszka Strzelczak

AbstractThis study presents the directions and the rate of changes occurring in the coastal lakes Jamno and Bukowo, located in northern Poland. Based on the cartographic materials and aerial photographs of those water bodies, it was established that in 1909–2012, the area of the lakes decreased by 183.6 ha (7.7%) and 250.7 ha (13.6%) for Jamno and Bukowo, respectively. Another component of lake disappearance — shallowing of lake basins — was analyzed using bathymetric plans. It turned out that water supplies of Jamno during more than 100 years decreased by 2.4 million m3 (5.9%), while in the case of Bukowo, it was 5.9 million (17.5%). Unfavorable location (inflow of pollutants from the basin) and morphometry of both lakes should be considered as the main causes of such major changes. The lakes are polymictic with a considerable area of the shallowest zone (1 m depth). This favors the vegetation succession and, consequently, shallowing of the lake basins. Moreover, direct connection with the Baltic Sea contributes to the fact that the materials of marine origin deposited in the form of a reverse delta also contribute to a decrease in the open water surface area.


2010 ◽  
Vol 10 (11) ◽  
pp. 2235-2240 ◽  
Author(s):  
D. G. Hadjimitsis

Abstract. The aim of this study is to quantify the actual urbanization activity near the catchment area in the urban area of interest located in the vicinity of the Agriokalamin River area of Kissonerga Village in Paphos District. Remotely sensed data such as aerial photos, Landsat-5/7 TM/ETM+ and Quickbird image data have been used to track the urbanization activity from 1963 to 2008. In-situ GPS measurements have been used to locate in-situ the boundaries of the catchment area. The results clearly illustrate that tremendous urban development has taken place ranging from 0.9 to 33% from 1963 to 2008, respectively. A flood risk assessment and hydraulic analysis were also performed.


Author(s):  
Kateryna Deineka ◽  
Yurii Naumenko

The influence of the structure of a two-fraction polygranular feed of the chamber on the value of the drum rotation speed at auto-excitation of self-excited oscillations with a maximum swing is considered. Such a pulsating mode of movement of the charge is used in the self-oscillating process of grinding in a tumbling mill. The coarse fraction simulated the grinding bodies was steel bullets with a relative size ψdb=0.026. The fine fraction, simulated the particles of the crushed material, was a cement clinker with a relative particle size ψdm=0.00013. Variable factors of experimental studies were: the degree of filling the chamber in the state of rest κbr=0.25; 0.29; 0.33 and the degree of filling the gaps between the particles of the coarse fraction with particles of the fine fraction κmbgr=0.0625; 0.375; 0.6875; 1. The method of visual analysis of transient processes of self-oscillating modes of feed behavior in the cross section of the rotating drum chamber is applied. Measurements of the speed limits of the drum rotation were carried out with auto-excitation of self-oscillations of the filling. The magnitude of the self-oscillation swing was estimated by the increase in the difference between the maximum and minimum values of the filling dilatancy for one period of pulsations. An increase in the upper limit of the speed range ψω2 with a decrease in κbr and κmbgr was established. The growth rate of ψω2 increases at low values of κbr and κmbgr. Some increase in the lower limit of the ψω1 range with a decrease in κbr and κmbgr was revealed. An increase in the range of speeds of rotation was recorded at the maximum range of self-oscillations ψω1–ψω2 with a decrease in the connected interaction of the intra-mill filling. This coherent interaction is due to an increase in κbr and κmbgr. The value of the ψω1–ψω2 range varies from 1.01–1.03 at κbr=0.33 and κmbg=1 to 1.22–1.66 at κbr=0.25 and κmbgr=0.0625. The range gets its maximum value with fine and superfine grinding


Author(s):  
Tamara Vieira Pascoto ◽  
Simone Andrea Furegatti ◽  
Anna Silvia Palcheco Peixoto

There are several factors that directly or indirectly influence erosion processes. In order to properly understand the behavior of these processes, some factors need to be analyzed together. Determining them wrongly can compromise the study resulting in wrong actions. For this reason, methodologies are always sought to measure them quantitatively and qualitatively in the most accurate possible way. Land use is one of the main factors liable to inaccuracies in its determination. To use this parameter in mapping erosive processes, researchers need to delimit it, classify it, and measure it. In order to better understand the complexity of considering this parameter, the present study analyzed an erosive feature that, although stabilized, has a component in constant development. Initially, a visual analysis indicated the same classification of land use for both conditions, despite having different behaviors, leading to the need for a detailed analysis. Such analysis comprised a historical survey through aerial photos and interviews with residents and employees of the city hall about the evolution of the feature from 2008 to 2019. It also included the analysis of other influencing factors that could be responsible for this difference in behavior in the area. Two different traces of the contribution areas of the gully and branch were also considered. One considering only aerial images, and the other considering the knowledge acquired during the research about the evolution of the feature. It was concluded, then, that an analysis of the use-only occupation factor based on aerial images can accentuate the inaccuracy of the measurement of this factor.


2010 ◽  
Vol 47 (3) ◽  
pp. 273-290 ◽  
Author(s):  
Sojan Mathew ◽  
Robin G.D. Davidson-Arnott ◽  
Jeff Ollerhead

Greenwich Dunes, Prince Edward Island National Park, is a sandy mainland and barrier spit beach–dune complex stretching for about 10 km along the northeast shore of Prince Edward Island, Canada. In October 1923, surge associated with an intense storm produced catastrophic overwash along the whole length of the study area. Subsequent evolution of the system was quantified from historic aerial photographs taken in 1936, 1953, 1971, 1997, and 2005. Orthophoto mosaics were generated for each photo set using PCI Geomatica OrthoEngine, a digital photogrammetric software. Linear changes in shoreline position and areal changes in geomorphic units were evaluated for each photo set. In addition, digital elevation models (DEMs) were extracted from the 1953, 1971, and 1997 aerial photos, enabling analysis of topographic and volumetric changes. The 1936 photos show complete destruction of all foredunes, with overwash and transgressive dunes extending 300 to 600 m inland. A descriptive model of the stages of evolution of the system is proposed based on the processes controlling overwash healing and dune stabilization. Detailed topographic and volumetric changes associated with the development of an extensive transgressive dunefield and subsequent stabilization as a result of reduced sand supply due to the growth of a new vegetated foredune complex and vegetation colonization are doccumented for each stage. It was nearly 40 years before a continuous foredune system was re-established and a further 30 years before the inland transgressive dunes became completely stabilized.


2020 ◽  
Author(s):  
Ji Won Suh ◽  
William Ouimet

<p>Orthomosaics from aerial photographs play a pivotal role in understanding land-use/land cover in broad area and the advent of image processing technology allows us to produce orthoimagery. However, recent advanced technologies are seldom applied to produce historical orthophotos from early or mid 20C old aerial photos in broad extent since they have limited information (e.g. camera position, flying altitude, and yaw) which is critical information for orthomosaics. In this context, this study aims to orthomosaic and georectify historical aerial photographs and validate the horizontal accuracy of orthomosacicked outputs. In order to achieve this, firstly, we collected 117 aerial photographs of 1934 (scale 1:12,000) and 68 of 1951 (scale 1:20,000) from UConn air photo achieve focused on Woodstock town in Connecticut, USA. Secondly, we created GCPs (Ground Control Points) as referenced points where they have not changed over time by overlaying multiple datasets such as LiDAR DEM, hillshade map, recent orthoimagery. Thirdly, we align photos with Control Points (CPs), build a mesh, and build orthomosaics of 1934 and 1951, respectively, using Agisoft Photoscan 1.5. Lastly, calculating RMSE (Root Mean Square Error) and offsets comparing between set of GCPs and CPs from Lidar DEM and set of them digitized from orthomosaics. As a result, RMSE values of GCPs and CPs between 1934 and 1951 mostly show that output of this work is acceptable to use for standard mapping and GIS work or visualization based on ASPRS 1990 horizonal accuracy standard. In addition, we found several factors affect horizontal accuracy of orthomosaics; resolution of aerial photos, spatial distribution of GCPs and CPs, the number of CPs and GCPs, the percentage of lateral overlapping area along flight strips, and margin area. Overall, applying automated orthomosaicking image processing to historical aerial photographs has the potential to represent historical landscape and even detect its change in broad extent.</p>


2018 ◽  
Vol 2 (1) ◽  
pp. 102-107
Author(s):  
Indreswari Suroso ◽  
Erwhin Irmawan

In the world of photography is very closely related to the unmanned aerial vehicle called drones. Drones mounted camera so that the plane is pilot controlled from the mainland. Photography results were seen by the pilot after the drone aircraft landed. Drones are unmanned drones that are controlled remotely. Unmanned Aerial Vehicle (UAV), is a flying machine that operates with remote control by the pilot. Methode for this research are preparation assembly of drone, planning altitude flying, testing on ground, camera of calibration, air capture, result of aerial photos and analysis of result aerial photos. There are two types of drones, multicopter and fixed wing. Fixed wing  has an airplane like shape with a wing system. Fixed wing use bettery 4000 mAh . Fixed wing drone in this research used   mapping in  This drone has a load ability of 1 kg and operational time is used approximately 30 minutes for an areas 20 to 50 hectares with a height of 100 m  to 200 m and payload 1 kg  above ground level. The aerial photographs in Kotabaru produce excellent aerial photographs that can help mapping the local government in the Kotabaru region.


2013 ◽  
Vol 44 (2s) ◽  
Author(s):  
Maria Nicolina Ripa ◽  
Francesco Ciapanna ◽  
Goffredo Filibeck ◽  
Federica Gobattoni ◽  
Antonio Leone ◽  
...  

Aerial photos represent the main existent database providing evidence of landscape changes with high detail. The analysis of land cover changes plays a key role in understanding a great variety of phenomena in several research fields. Landscapes are made by society and reflect the changing society and attitude towards the environment. The reorientation of farming system, the practical results of planning processes, the rate and magnitude of the changes in the landscape are some of the most important factors relating to the evolution of our landscapes and are very helpful for the understanding of evolution processes and consequently for the design of landscape-orientated policies. Pressures upon the landscape and values of our landscapes can be defined according to their traditional characteristics; traditional landscapes can be defined as those landscapes having a distinct and recognizable structure, which reflect relations between the composing elements and have a significance for natural, cultural or aesthetical values. In most cases, such landscapes evolved slowly and took centuries to form their values. Sometimes land changes happen fast and spread in vast areas so that some agricultural or natural landscapes, widely perceived as traditional, have very recent origin. In this paper, some preliminary observation and case-studies performed on a set of historical photos are dealt with. In 1935, the Italian Land Register Department commissioned SARA company to survey Viterbo province between 1935-1938 through aerial photographs. During the survey, 5,000 photographs on glass plates were taken at a very low altitude, featuring a very high resolution. Thus, they represents a valuable source of information for documenting past and present land-use practices, local cultural heritage and changes in the landscape. Processing this set of historical photos has started, aimed to quantitatively and qualitatively analyse the 1935-1938 landscape patterns and their role in the development of nowadays landscapes.


2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Maher Ibrahim Sameen ◽  
Biswajeet Pradhan ◽  
Omar Saud Aziz

Classification of aerial photographs relying purely on spectral content is a challenging topic in remote sensing. A convolutional neural network (CNN) was developed to classify aerial photographs into seven land cover classes such as building, grassland, dense vegetation, waterbody, barren land, road, and shadow. The classifier utilized spectral and spatial contents of the data to maximize the accuracy of the classification process. CNN was trained from scratch with manually created ground truth samples. The architecture of the network comprised of a single convolution layer of 32 filters and a kernel size of 3 × 3, pooling size of 2 × 2, batch normalization, dropout, and a dense layer with Softmax activation. The design of the architecture and its hyperparameters were selected via sensitivity analysis and validation accuracy. The results showed that the proposed model could be effective for classifying the aerial photographs. The overall accuracy and Kappa coefficient of the best model were 0.973 and 0.967, respectively. In addition, the sensitivity analysis suggested that the use of dropout and batch normalization technique in CNN is essential to improve the generalization performance of the model. The CNN model without the techniques above achieved the worse performance, with an overall accuracy and Kappa of 0.932 and 0.922, respectively. This research shows that CNN-based models are robust for land cover classification using aerial photographs. However, the architecture and hyperparameters of these models should be carefully selected and optimized.


1965 ◽  
Vol 2 (4) ◽  
pp. 247-269 ◽  
Author(s):  
S. C. Zoltai

The surficial deposits, ice movements, and glacial lakes are described within an area of 25 000 square miles in northwestern Ontario. Field studies and subsequent interpretation of aerial photographs suggest the existence of two major and one minor ice mass during late Wisconsin glaciation. Movements by the various ice masses are shown and correlated. The extent of several glacial lakes and their drainage channels are described. A reconstruction of the sequence of events, based on morphological features, allows a tentative correlation of Glacial Lake Agassiz in the west with Glacial Lake Minong stages in the Superior basin. A radiocarbon date of 9 380 ± 150 years B.P. (GSC No. 287) was obtained from wood buried in a post-Minong beach.


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