scholarly journals Lifelong training program on QGIS tools for earth observation sciences in south-east Europe

2021 ◽  
Vol 12 (3) ◽  
pp. 88-102
Author(s):  
Bashkim IDRIZI ◽  
◽  
Lyubka PASHOVA ◽  
Pal NIKOLLI ◽  
◽  
...  

Earth Observation (EO) data are an indispensable source of useful geospatial information, which can be efficiently combined with other data within the latest released open-source QGIS software. This paper aims: i) to present a general overview of the QGIS EO plugins; ii) to promote the Lifelong Learning (LLL) courses for open-source QGIS software tools provided by the Geo-SEE Institute from Skopje; iii) to appreciate the advantages of open-source QGIS for developing and improving EO applications. The training objectives are to enhance the research, development tools and technologies of QGIS and stimulate the obtaining and disseminating knowledge to utilize the open-source GIS software. Furthermore, there is a growing need to increase the number of well-educated professionals on issues related to the EO sciences in South-East Europe (SEE), who are better prepared for the labor market in today's digital revolution by using QGIS tools and plugins combined with other related GIS software platforms provided by the OSGeo family.

Poljoprivreda ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 52-59
Author(s):  
Mladen Jurišić ◽  
◽  
Dorijan Radočaj ◽  
Ivan Plaščak ◽  
Irena Rapčan

Fertilization is one of the most important components of precision agriculture, ensuring high and stable crop yields. The process of spatial interpolation of soil sample data is recognized as a reliable method of determining the prescription rates for precise fertilization. However, the application of a free open-source geographic information system (GIS) software was often overlooked in the process. In this study, a method of precise fertilization prescription map creation was developed using an open-source GIS software to enable a wider and cheaper availability of its application. The study area covered three independent locations in Osijek-Baranja County. A method was developed for the fertilization of sugar beet with phosphorous pentoxide, but its application is universal with regard to the crop type. An ordinary kriging was determined as an optimal interpolation method for spatial interpolation, with the mean RMSE of 1.8754 and R2of 0.6955. By comparing the precision fertilization prescription rates to a conventional approach, the differences of 4.1 kg ha-1 for Location 1, 15.8 kg ha-1 for Location 2, and 11.2 kg ha-1 for Location 3 were observed. These values indicate a general deficit in soil phosphorous pentoxide, and precise fertilization could ensure its optimal content in the future sowing seasons.


Author(s):  
Shahriar Shams

There has been a significant development in the area of free and open source geospatial software. Research has flourished over the decades from vendor-dependent software to open source software where researchers are paying increasing attention to maximize the value of their data. It is often a difficult task to choose particular open source GIS (OGIS) software among a number of emerging OGIS software. It is important to characterise the projects according to some unified criteria. Each software has certain advantages and disadvantages and it is always time consuming to identify exactly which software to select for a specific purpose. This chapter focuses on the assessment criteria enabling developers, researchers, and GIS users to select suitable OGIS software to meet their requirements for analysis and design of geospatial application in multidisciplinary fields. This chapter highlights the importance of assessment criteria, followed by an explanation of each criteria and their significance with examples from existing OGIS software.


Fisheries ◽  
2014 ◽  
Vol 39 (5) ◽  
pp. 217-217
Author(s):  
Thom Litts

2020 ◽  
Author(s):  
Valerio Baiocchi ◽  
Roberta Onori ◽  
Felicia Monti ◽  
Francesca Giannone

<p>High and very high resolution satellite images are now an irreplaceable resource for earth observation in general and for the extraction of hydrogeological information in particular. In order to use them correctly and compare them with previous surveys and maps, they must be treated geometrically to remove the distortions introduced by the acquisition process. Orthorectification is not a simple georeferencing because the process must take into account the three-dimensional acquisition geometry of the sensor. For this reason orthorectification must be performed within specific commercial software with additional costs compared to image acquisition which, in some cases, is currently free of charge.<br>Some orthorectification algorithms, mainly based on the RPC approach, are available in open source GIS software such as QGIS. OTB (Orpheus toolbox) for QGIS contains some of these algorithms but its interfaces are not clear and there are some incomprehensible limitations such as the impossibility to input three-dimensional ground control points (GCPs). This severely limits the final achievable accuracy because it does not allow to correctly estimate the influence of different ground morphologies on the acquisition geometry. To get around these limitations you can make a "pseudo DEM" and other expedients to complete the whole process obtaining absolute results comparable if not better than those of commercial software.<br>The proposed procedure may not be the fastest but it can be a valid alternative for those who use satellite images as a tool in their research work.</p><p> </p>


2018 ◽  
Author(s):  
Luís Moreira de Sousa

The volume and coverage of spatial data has increased dramatically in recent years, with Earth observation programmes producing dozens of GB of data on a daily basis. The term Big Spatial Data is now applied to data sets that impose real challenges to researchers and practitioners alike. The difficulties are partly related to a lack of tools supporting appropriate Coordinate Reference Systems (CRS). As rule, these data are provided in highly irregular geodesic grids, defined along equal intervals of latitude and longitude. Compounding the problem, users of such data end up taking geodesic coordinates in these grids as a Cartesian system, implicitly applying Marinus of Tyre's projection. A first approach towards the compactness of global geo-spatial data is to work in a Cartesian system produced by an equal-area projection. There are a good number to choose from, but those commonly supported by GIS software invariably relate to the sinusoidal or pseudo-cylindrical families, that impose important distortions of shape and distance. The land masses of Antarctica, Alaska, Canada, Greenland and Russia are particularly distorted with such projections. A more effective approach is to store and work with data in modern cartographic projections, in particular those defined with the Platonic and Archimedean solids. In spite of various attempts at open source software supporting these projections, in practice they remain today largely out of reach to GIS practitioners. This communication reviews persisting difficulties in working with worldwide big spatial data, current strategies to address such difficulties, the compromises they impose and the remaining gaps in open source software.


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