scholarly journals МАСШТАБНО-ЗАВИСИМЫЕ ЭФФЕКТЫ В СТРУКТУРЕ ЭКОЛОГИЧЕСКОЙ НИШИ ЛЕБЕДЯ-ШИПУНА CYGNUSOLOR (GMELIN, 1803) В ПЕРИОД ЗИМОВКИ В ПРЕДЕЛАХ ЗАЛИВА СИВАШ

Author(s):  
A. Yu. Andrushenko ◽  
A. V. Zhukov

<p>The assessment of the information value of ecogeographical predictors based on remote sensing data from satellites to reflect features of the ecological niche of the Swan-mute <em>Cygnus up</em> (Gmelina, 1803) in wintering within the Gulf Sivash have been presented. Two groups predictors of ecogeographical landscape data have been considered. The first group is assigned digital elevation model and its derivatives. The second set of classified vegetation indices obtained from Landsat 8 image. Ecological niche has been described using ENFA-procedure. The procedure of random distribution of the pseudo-absent points which range from the presence points restricted by some distance has been applied to assess the role of scale in ecological niche. Ecological niche of Swan mute has been shown to be described in terms of landscape ecogeographical variables. The properties of the ecological niche of the Swan-mute have been found to be depends upon the scale of its consideration. Under various boundary ranges we can get an entirely different, but statistically valid, assess the structure of the ecological niche of the Swan-mute based landscape ecogeographical predictors. The role of the various ecogeographical predictors depending on the scale can vary greatly.</p>

2020 ◽  
pp. 69-77
Author(s):  
Anju Jangra ◽  
Anurag Airon ◽  
Ram Niwas

Forest is an essential part or backbone of the earth ecological system. In a country like India, the people and the economy of nation is mainly relies on the diversity of natural resources. In today's world degradation of forest resources is a prime concern for many of the scientists and environmentalists because the canvas had been transformed from last few decades to cultivated and non-cultivated land. In India, Haryana state has lowest forest cover i.e. 3.59% followed by Punjab 3.65%. Over the several decades, the advancement of Remote Sensing and Geographical Information System (GIS) technique has emerged as an efficient tool to monitor and analyse deforestation rate in hilly areaor over a variety of location. Remote sensing based vegetation indices show better sensitivity than individual band reflectance and hence are more preferred for assessment and monitoring of tress. The aim of the present study was to analyse the deforestation in hilly areas in Haryana State (India) by remote sensing data with a special focus on Panchkula and Yamunanagar. The information was collected through the LANDSAT 8 satellite of NASA. The result revealed that the deforestation rate is high in Hilly areas of Haryana. The study shows that the forest cover in hilly areas of Haryana in 2013 was 50,879.07 hectares and in 2019 it was 44,445.51 hectares of land. Thereby decrease in forest cover of 6,433.56 hectares had been observed in the study period of 2013-2019 i.e. 6 years. Spatial variations in deforestation were also mapped in GIS for the hilly areas in Panchkula and Yamunanagar districts of Haryana.  


Geosciences ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 248 ◽  
Author(s):  
Mariaelena Cama ◽  
Calogero Schillaci ◽  
Jan Kropáček ◽  
Volker Hochschild ◽  
Alberto Bosino ◽  
...  

Soil erosion represents one of the most important global issues with serious effects on agriculture and water quality, especially in developing countries, such as Ethiopia, where rapid population growth and climatic changes affect widely mountainous areas. The Meskay catchment is a head catchment of the Jemma Basin draining into the Blue Nile (Central Ethiopia) and is characterized by high relief energy. Thus, it is exposed to high degradation dynamics, especially in the lower parts of the catchment. In this study, we aim at the geomorphological assessment of soil erosion susceptibilities. First, a geomorphological map was generated based on remote sensing observations. In particular, we mapped three categories of landforms related to (i) sheet erosion, (ii) gully erosion, and (iii) badlands using a high-resolution digital elevation model (DEM). The map was validated by a detailed field survey. Subsequently, we used the three categories as dependent variables in a probabilistic modelling approach to derive the spatial distribution of the specific process susceptibilities. In this study we applied the maximum entropy model (MaxEnt). The independent variables were derived from a set of spatial attributes describing the lithology, terrain, and land cover based on remote sensing data and DEMs. As a result, we produced three separate susceptibility maps for sheet and gully erosion as well as badlands. The resulting susceptibility maps showed good to excellent prediction performance. Moreover, to explore the mutual overlap of the three susceptibility maps, we generated a combined map as a color composite where each color represents one component of water erosion. The latter map yields useful information for land-use managers and planning purposes.


Author(s):  
Andrew N. Beshentsev ◽  
◽  
Alexander A. Ayurzhanaev ◽  
Bator V. Sodnomov ◽  
◽  
...  

The article is aimed at the development of methodological foundations for the creation of geoin-formation resources of transboundary territories based on cartographic materials and remote sensing data, as well as physical and geographical zoning of the transboundary Russian-Mongolian territory. The methodological basis of the study is cartographic and statistical research methods, geoinformation technology, as well as processing and analysis of remote sensing data. As a result, the study deter-mines the features of geoinformation resources, presents their characteristics, develops a classification and substantiates their integrating value in making interstate territorial decisions. The article gives the physical and geographical characteristics of the territory, determines the scale of mapping, establishes the basic units of geoinformation mapping and modeling, creates the coverage of the basin division, and proposes a scheme for creating basic geoinformation resources for the physical and geographical zoning of the territory. Based on the analysis of the digital elevation model, the territory was zoned according to the morphometric parameters of the relief. As a result of processing and analysis of Landsat images at different times, the territory was zoned in terms of the amount of photosynthetically active biomass (NDVI). As a result of zoning, 6 physical-geographical regions and 33 physical-geographical areas were identified.


2021 ◽  
Author(s):  
mageswaran thangaraj ◽  
Sachithanandam V ◽  
Sridhar R ◽  
Manik Mahapatra ◽  
R Purvaja ◽  
...  

Abstract We report here a four decades of shoreline changes and possible sea level rise (SLR) impact on landuse/landcover (LULC) in Little Andaman Island by using remote sensing (RS) and GIS techniques. A total of six remote sensing data sets covering years between 1976 and 2018 were used to understand the shoreline changes. Moreover, a Digital Shoreline Analysis System (DSAS) was used to estimate short- and long- term shoreline changes from ArcGIS environment. Besides, the Island vulnerability due to SLR was studied through using digital elevation model (DEM). As a result of Sumatra earthquake (2004), the results were showed a significant variation in shorline upliftment and subsidence. The land subsidence was noticed in the range of 1042-3077 ha with sea level rise between 1 and 5 m. Hence, we conclude that Little Andaman Island is vulnerable to SLR and overwhelm low elvation coastal zone.


2020 ◽  
Vol 954 (12) ◽  
pp. 20-30
Author(s):  
Yu.V. Vanteeva ◽  
Е.А. Rasputina ◽  
S.V. Solodyankina

The authors present the results of geoinformation mapping the Primorskiy Ridge landscapes using Landsat 8 satellite images, the digital elevation model SRTM and the factor-dynamic classification of geosystems. At the first stage, the remote sensing data for different seasons were classified using the ISODATA method. Then, using the digital elevation model, the landforms were classified basing upon the topographic position index. According to combining the classification parameters of one of the space images and digital elevation model, each polygon is automatically assigned to a certain preliminary type of landscapes using boolean expressions. Legend adjustments were made basing upon the fieldwork materials. As a result, a digital landscape map of the southern part of the Primorsky Ridge was created; it reflects the landscape structure at the level of facies groups and contains attributive information about the landform, altitude, slope and aspect, topographic wetness index. The analysis of the landscape pattern showed a high fragmentation of landscape polygons, formed due to overlay operations, which indicates the need for generalization of landscape contours.


2021 ◽  
Vol 70 (1) ◽  
pp. 29-38
Author(s):  
Robert Schiestl

Abstract. The Butic Canal – a Roman period transversal route across the northern Nile Delta – was the longest artificial watercourse in the Nile Delta, yet it remains very poorly understood. To date, the canal has not yet been verified by archeological excavations. The route of the eastern section of the canal has been indirectly identified based on a linear elevated feature most likely representing earth from the excavation of the canal. This study combines the analysis of historical sources and remote sensing data, such as satellite imagery and the TanDEM-X digital elevation model, in order to discuss its date of construction, route, and functions. Based on the data of the digital elevation model, new constructional features are visible in the eastern delta providing the first detailed route of a Roman-era artificial watercourse in Egypt. It is suggested that the canal's construction is placed in the context of imperial investments in the infrastructure of the eastern part of the Roman empire.


2007 ◽  
Vol 79 (4) ◽  
pp. 693-711 ◽  
Author(s):  
Clauzionor L. Silva ◽  
Norberto Morales ◽  
Alvaro P. Crósta ◽  
Solange S. Costa ◽  
Jairo R. Jiménez-Rueda

An investigation of the tectonic controls of the fluvial morphology and sedimentary processes of an area located southwest of Manaus in the Amazon Basin was conducted using orbital remote sensing data. In this region, low topographic gradients represent a major obstacle for morphotectonic analysis using conventional methods. The use of remote sensing data can contribute significantly to overcome this limitation. In this instance, remote sensing data comprised digital elevation model (DEM) acquired by the Shuttle Radar Topographic Mission (SRTM) and Landsat Thematic Mapper images. Advanced image processing techniques were employed for enhancing the topographic textures and providing a three-dimensional visualization, hence allowing interpretation of the morphotectonic elements. This led to the recognition of main tectonic compartments and several morphostructural features and landforms related to the neotectonic evolution of this portion of the Amazon Basin. Features such as fault scarps, anomalous drainage patterns, aligned ridges, spurs and valleys, are expressed in the enhanced images as conspicuous lineaments along NE-SW, NW-SE, E-W and N-S directions. These features are associated to the geometry of alternated horst and graben structures, the latter filled by recent sedimentary units. Morphotectonic interpretation using this approach has proven to be efficient and permitted to recognize new tectonic features that were named Asymmetric Ariaú Graben, Rombohedral Manacapuru Basin and Castanho-Mamori Graben.


2018 ◽  
Vol 53 (3) ◽  
pp. 332-341 ◽  
Author(s):  
André Geraldo de Lima Moraes ◽  
Daniel Fonseca de Carvalho ◽  
Mauro Antonio Homem Antunes ◽  
Marcos Bacis Ceddia

Abstract: The objective of this work was to evaluate the relationship between different remote sensing data, derived from satellite images, and interrill soil losses obtained in the field by using a portable rainfall simulator. The study was carried out in an area of a hydrographic basin, located in Médio Paraíba do Sul, in the state of Rio de Janeiro - one of the regions most affected by water erosion in Brazil. Evaluations were performed for different vegetation indices (NDVI, Savi, EVI, and EVI2) and fraction images (FI), derived from linear spectral mixture analysis (LSMA), obtained from RapidEye, Sentinel2A, and Landsat 8 OLI images. Vegetation indices are more adequate to predict soil loss than FI, highlighting EVI2, whose exponential model showed R2 of 0.74. The best prediction models are generated from the RapidEye image, which shows the highest spatial resolution among the sensors evaluated.


Author(s):  
Valerii Kulygin ◽  
Samir Misirov

The study of the ridge systems’ morphology on accumulative coastal land forms makes it possible to reconstruct their development. The spatial orientation and height of the beach ridges provide information on the predominance of certain processes at different time intervals. The Dolgaya Spit, which is one of the largest accumulative forms of the Sea of Azov, is characterized by the presence of well-distinguishable generation of sand-shell ridges. The article discusses the possibility of using various remote sensing data to identify beach ridges on the Dolgaya Spit. In this study the data of ground measurements of elevation points performed during the expedition in the summer of 2020 are used. The statistical characteristics of the ridges on the investigated area of the spit are given. The analysis of the possibility of identifying beach ridges on the spit based on high-resolution satellite optical images has been done. It was concluded that it is impossible to unambiguously determine the ridges, since the optical characteristics of the soil and vegetation cover on the Dolgaya Spit do not allow separation of the microrelief forms. The second source of remote sensing data was aerial photography of a part of the Dolgaya Spit using the unmanned aerial vehicle “Phantom 3 PRO”, followed by photogrammetric processing of the obtained digital images. The stages of processing the survey results for the construction of a digital elevation model and an orthomosaic of the investigated area are considered. The quality of the obtained digital elevation model was assessed by comparison with ground measurements of elevation points. The article discusses the source of errors in the obtained digital elevation model. It is noted that the construction of a digital elevation model with acceptable quality is possible only for the spit’s regions with sparse vegetation cover.


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