scholarly journals Erosion Prediction Model using Fractional Vegetation Cover

2020 ◽  
Vol 5 (1) ◽  
pp. 125-132
Author(s):  
Nursida Arif ◽  
Projo Danoedoro ◽  
Hartono Hartono ◽  
Andrew Mulabbi
Keyword(s):  
Prediction Model ◽  
Vegetation Cover ◽  
Input Data ◽  
Medium Density ◽  
Vegetation Density ◽  
Erosion Model ◽  
Fractional Vegetation Cover ◽  
Erosion Prediction ◽  
Digital Elevation ◽  
Elevation Model

The purpose of this study was to  create an erosion prediction model in Serang Watershed, Indonesia. The erosion model used two input data, namely the slope derivied from Digital Elevation Model (DEM) data, and Fractional Vegetation Cover (FVC) from SPOT images. Assessment of the model was carried out using questionnaires and interviews with several experts by presenting the results of the model and its supporting data. Based on the DEM data, the level of slope steepness in the study area is very varied namely; flat (52.77%), sloping (7.62%), and rather steep to very steep (39.59%). Vegetation density according to the FVC results is dominated by medium density. The results of the analysis of the two input models can provide predictions of the level of erosion with an accuracy of 67.92%. Evaluation of the model was done by experts with conclusions that the method was very flexible and can be adapted to similar watersheds elsewhere.

A Load Balanced Parallel Ground Visualization Tool

1997 ◽  
Vol 11 (07) ◽  
pp. 1113-1127
Author(s):  
Sylvain Contassot-Vivier
Keyword(s):  
Input Data ◽  
Parallel Implementation ◽  
Point Of View ◽  
Visualization Tool ◽  
Rectangular Region ◽  
Raster Image ◽  
Digital Elevation ◽  
Elevation Model ◽  
The Cost ◽  
Load Balanced

We propose in this paper, a parallel implementation of a ground visualization algorithm. Our input data consist in a Digital Elevation Model (DEM) covering a rectangular region, together with a raster image of the same area (the texture). The goal of the algorithm is to compute in parallel, images of the DEM from any point of view while mapping the texture onto the surface. The main originality of our approach concerns the distribution of the data, leading to a load-balanced and scalable parallel algorithm. We use a workload estimation to partition the output image, and then redistribute the input data according to this division. Special attention is paid on the data structures used for minimizing the cost of communications.

scholarly journals Scenario of Vegetation Density for an Erosion Prediction Model

2020 ◽  
Vol 437 ◽  
pp. 012057
Author(s):  
Sudarto ◽  
Lily Montarcih Limantara ◽  
Very Dermawan ◽  
Agus Suharyanto
Keyword(s):  
Prediction Model ◽  
Vegetation Density ◽  
Erosion Prediction

scholarly journals Kajian Potensi Erosi Di Daerah Aliran Sungai Babon Menggunakan Permodelan GeoWEPP

G - SMART ◽  
2021 ◽  
Vol 3 (2) ◽  
pp. 98
Author(s):  
Revangga Dandha Pratama ◽  
Dimas Jalu Setyawan ◽  
Budi Santosa
Keyword(s):  
Erosion Rate ◽  
River Flow ◽  
Water Erosion ◽  
Climate Data ◽  
Erosion Prediction ◽  
Digital Elevation ◽  
Water Erosion Prediction Project ◽  
Type Data ◽  
Hazard Level ◽  
Elevation Model

At the time of the high intensity of rainfall in Semarang, the water contained in the Babon River had overflowed, resulting in flooding of parts of the area adjacent to the Babon river flow. This matter has many factors, there are erosion and sediment produced. This study aims to study erosion potential in the Babon watershed, using the Geospatial Interface for Water Erosion Prediction Project (GeoWEPP) modeling. The results of the modeling are the amount of erosion rate and erosion distribution in the study area. The erosion prediction period in this study is in 2006 - 2015. Data needed in GeoWEPP operation are Digital Elevation Model, climate data, land use data, and soil type data. Based on the GeoWEPP process in the Babon watershed the erosion rate was 36.1 tons / ha / year and the sediment yield was 26075.2 tons / year. From the results of the erosion rate produced divided by the reasonable erosion rate get the Erosion Hazard Level index (TBE) of 3.6 or including medium TBE. Based on the distribution of erosion maps produced, the area experienced the greatest erosion rate in the Ungaran region. This is due to the fact that it belongs to the highlands and has a high slope value.

Matters of choosing the pixel size in topographic aerial photography

2021 ◽  
Vol 977 (11) ◽  
pp. 27-39
Author(s):  
V.I. Yurchenko
Keyword(s):  
Aerial Photography ◽  
Input Data ◽  
Large Scale ◽  
Aerial Survey ◽  
Minimum Size ◽  
Digital Cameras ◽  
Pixel Size ◽  
Digital Elevation ◽  
Elevation Model ◽  
Navigation Equipment

The existing regulatory documents on photogrammetric works are technologically outdated. They neither take into account the peculiarities of aerial photography with digital cameras, the navigation equipment used and modern image processing methods, nor regulate the technique of calculating the pixel size on the ground. In order to select the pixel size in the terrain for aerial photography with topographic requirements concerning to the results, the method of multivariate analysis of the input data is proposed. It is supposed to ensure the minimum pixel size on the ground according to such criteria as the accuracy of the aerial triangulation results, the accuracy of building a digital elevation model for orthotransformation, the possibility of the objects interpretation with a specified minimum size and consideration of camera exposure parameters. To determine the accuracy criteria, we used formulas for pre- calculation of spatial phototriangulation accuracy with multiple choice of parameters. Examples of pixel size selection in the terrain at designing aerial photography by an amateur camera for the purposes of large-scale mapping are considered. Conclusions on the necessity of solving the issues of selecting parameters of large scale aerial photography, taking into account multiple input data and used aerial survey equipment are made.

scholarly journals Beach ridges detection on the Dolgaya Spit based on remote sensing data

2021 ◽  
Vol 27 (1) ◽  
pp. 330-338
Author(s):  
Valerii Kulygin ◽  
Samir Misirov
Keyword(s):  
Remote Sensing ◽  
Digital Elevation Model ◽  
Vegetation Cover ◽  
Remote Sensing Data ◽  
Statistical Characteristics ◽  
Beach Ridges ◽  
Sensing Data ◽  
Sparse Vegetation ◽  
Digital Elevation ◽  
Elevation Model

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.

scholarly journals Relational Modelling of the Earth's Surface Topography Impact on Vegetation Density Using RS and GIS: Rawnduz as a Model

2021 ◽  
Vol 16 (4) ◽  
pp. 435-444
Author(s):  
Ameer Mohammed Khalaf ◽  
Zuhair Jaber Mushref ◽  
Ismael Mohammed Khaleefah ◽  
Salah Othman Abed
Keyword(s):  
Plant Density ◽  
Research Area ◽  
Average Density ◽  
Vegetation Coverage ◽  
Vegetation Density ◽  
Search Area ◽  
Rs And Gis ◽  
Ndvi Index ◽  
Digital Elevation ◽  
Elevation Model

Through the analysis of the digital elevation model (DEM) of the search area, it was found that the search area is located within a mountainous region with a complex twisting, as the surface has been classified into five regions of elevations, among which the first region represents the lowest elevation lands, and extends an area of 118.7 km2 It equates to (22.6%) of the total area, while the largest region is the second region, occupying an area of (187.9) km2, 36% of the total area of the region, while the regression categories were divided into five levels depending on the classification of (Zink) It turns out that the Fifth Region is the most complex of the regions, and it includes the summit of Mount Hendrin, the summit of Mount Karukh. As for the characteristics of the direction of the slopes, nine slope directions of varying areas were found. As for the density of vegetation coverage according to (NDVI), we find that the NDVI index in the research area is divided into three levels of plant density, as the second level, i.e. average density, recorded the largest area at about (344.8) km2, equivalent to (66.1%) of the area the college. Which is characterized by the topological complexity of the surface, which makes it the most suitable areas for pastoral activity, while the higher density in relation to vegetation coverage was more widespread in the first and second steep categories by about (2.5, 9.8) km2, i.e. (21.6%, 24.3%) of the total area.

Caracteristici morfometrice ale reliefului bazinului râului Bucovăț

2019 ◽  
Author(s):  
Andrei Craciun ◽  
◽  
Iurie Bejan ◽  
Keyword(s):  
Digital Elevation Model ◽  
Input Data ◽  
General Information ◽  
Virtual Space ◽  
Digital Terrain ◽  
Digital Elevation ◽  
Elevation Model ◽  
Digital Terrain Modeling ◽  
Geomorphometric Parameters ◽  
Topographical Attributes

In the sense of digital terrain modeling, there is a set of techniques for obtaining a Digital Elevation Model (DEM). But, as expected, modeling the terrestrial surface, its representation in a virtual space, involves certain problems that are related to the surface specificity itself and our way of measuring it. Numerical altitude models, once performed, find their usefulness as input data for derivation of some topographical attributes of geomorphometric parameters, morphometric variables or general information about the land respectively.

scholarly journals High Resolution Apparent Thermal Inertia Mapping on Mars

2021 ◽  
Vol 13 (18) ◽  
pp. 3692
Author(s):  
Marta Ciazela ◽  
Jakub Ciazela ◽  
Bartosz Pieterek
Keyword(s):  
High Resolution ◽  
Significant Influence ◽  
Input Data ◽  
High Spatial Resolution ◽  
Resistance To Change ◽  
Incidence Angle ◽  
Thermal Inertia ◽  
Surficial Geology ◽  
Digital Elevation ◽  
Elevation Model

Thermal inertia, which represents the resistance to change in temperature of the upper few centimeters of the surface, provides information to help understand the surficial geology and recent processes that are potentially still active today. It cannot be directly measured on Mars and is therefore usually modelled. We present a new analytical method based on Apparent Thermal Inertia (ATI), a thermal inertia proxy. Calculating ATI requires readily available input data: temperature, incidence angle, visible dust opacity, and a digital elevation model. Because of the high spatial resolution, the method can be used on sloping terrains, which makes possible thermal mapping using THEMIS in nearly any area of Mars. Comparison with results obtained by other approaches using modeled data shows similarity in flat areas and illustrates the significant influence of slope and aspect on albedo and diurnal temperature differences.

scholarly journals Impacts of spatial data resolution on simulated discharge, a case study of Xitiaoxi catchment in South China

2009 ◽  
Vol 21 ◽  
pp. 131-137 ◽  
Author(s):  
G. J. Zhao ◽  
G. Hörmann ◽  
N. Fohrer ◽  
J. F. Gao
Keyword(s):  
Land Use ◽  
Cell Size ◽  
Digital Elevation Model ◽  
South China ◽  
Spatial Data ◽  
Input Data ◽  
Grid Size ◽  
Digital Elevation ◽  
Data Resolution ◽  
Elevation Model

Abstract. In this paper we analyse the effects of different spatial input data resolution on water balance simulation using a simple distributed hydrological model: PCR-XAJ model. A data set consisting of land use and digital elevation model at 25 m resolution of Xitiaoxi catchment in South China is used for investigation. The model was first calibrated and validated at 50 m cell size, thereafter an aggregation of the digital elevation model (DEM) and land use maps at 100 m, 200 m, 300 m, 500 m and 1 km are applied to evaluate the effects of spatial data resolution on simulated discharge. The simulation results at a grid size of 50 m show a good correlation between measured and simulated daily flows at Hengtangcun station with Nash-Suttcliffe efficiency larger than 0.75 for both calibration and validation periods. In contrast, the model performs slightly worse at Fanjiacun station. The increasing grid size affects the characteristics of the slope and land use aggregation and causes important information loss. The aggregation of input data does not lead to significant errors up to a grid of 1 km. Model efficiencies decrease slightly with cell size increasing, and more significantly up to the grid size of 1 km.

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