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3D RGB drape rendered as .gif file, Miellejohka, Abisko Scientific Research Station. A high resolution version can be downloaded further down. 3D RGB drape rendered as .gif file, Miellejohka, Abisko Scientific Research Station. A high resolution version can be downloaded further down.
A new dataset called ‘3D RGB Drape’ is defined and tested for UAV (drone) images available for SITES stations. Shangharsha Thapa from SITES Spectral describes this new product.

Images from Unmanned Aerial Vehicle (UAV) present a way to generate accurate and high-resolution topographic products such as orthomosaics (combination of aerial photograph or satellite imagery of a large area) and digital surface models (DSMs) in a fast and economical way. However, the orthomosaics and DSMs that are obtained after processing the UAV images may be quite heavy in terms of file size, which makes them challenging to disseminate to users. A 2D orthomosaic and elevation map can be a very good way of presenting the land use and topography within the flight area (Figure 1). However, to prepare and disseminate such maps, one must have prior basic knowledge of GIS and also access to available GIS applications (such as ArcGIS and QGIS).
Figure 1: RGB Orthomosaic (Left) and DEM (Right) of UAV flight conducted at Miellejohka location, Abisko Scientific Research Station on 2018-07-28.
Figure 1: RGB Orthomosaic (Left) and DEM (Right) of UAV flight conducted at Miellejohka location, Abisko Scientific Research Station on 2018-07-28.
So, to make the data visualization and dissemination simple, realistic, easy to handle, and GIS platform-independent, a new dataset called ‘3D RGB Drape’ has been defined and tested for UAV images available for SITES stations. In this new dataset, the RGB orthomosaics are draped on top of the 3D surfaces (digital terrain model, DTM) to give  a more realistic appearance.

There is a wide range of techniques or applications that offer 3D solutions. Qgis2threejs, Blender GIS, Mayavi, Rayshader, and ArcGIS are some examples. The first four packages are open-source platforms, while the last one is commercial. All these platforms were tested to generate 3D RGB drapes, and it was found that the R-package Rayshader offered the best results, both in terms of quality and high-resolution data handling.

Rayshader is an open-source package for producing 2D and 3D hill shaded maps of elevation matrices using a combination of raytracing, spherical texture mapping, overlays, and ambient occlusion (adopted from Dr. Tyler Morgan’s website). The process of rendering a 3D scene begins with plotting an elevation matrix. A hillshade is generated and plotted from the elevation matrix with a Z-scale factor ranging from 0.05 to 0.2 depending on the elevation variation within the area. The shadow layers are successively added on the plotted hillshade, and the result is printed on the screen with OpenGL (Figure 2).
Figure 2: Hillshade for DEM of Miellejohka location, Abisko Scientific Research Station.
Figure 2: Hillshade for DEM of Miellejohka location, Abisko Scientific Research Station.
Now, that the 3D hill shaded surface is ready, it is time for overlaying RGB orthomosaics on top of it. Before draping the orthomosaic, one must ensure that the overlay image dimensions match the elevation data dimensions. Below is an example of one of the static rendered snapshots of orthomosaics from the flight area at Abisko, but locally one can interact with the 3D plot at this stage.
Figure 3: 3D RGB Drape of Miellejohka UAV flight area, Abisko Scientific Research Station.
Figure 3: 3D RGB Drape of Miellejohka UAV flight area, Abisko Scientific Research Station.
One of the most eye-catching features of Rayshader is its ability to export the rendered 3D surface into a different file format such as .mp4, .obj, and .gif. An .obj file is a standard 3D image format that can be viewed by various 3D image viewers. There are several functions available within the Rayshader package for the creation of any of these file formats. The function allows capturing the user-defined number of snapshots of the rendered 3D from different angles. All these snapshots are looped to stitch them into an .mp4, .obj, or .gif file (Figure 4). The .gif file is easier to attach to websites for visualization, in PowerPoint presentations, and has several different applications. With the use of a simple few lines of code, one can come up with exciting 3D maps to help bring the UAV photogrammetric products to life.
Abisko Scientific Research Station. Photo: Thomas Westin. Abisko Scientific Research Station. Photo: Thomas Westin.
At SITES stations, work aimed at reducing the negative environmental impact is ongoing. One station that is trying to lead by example is Abisko Research Station. Station Manager Magnus Augner reports on the current environmental development in Abisko.

"We all have the three major tasks to carry out and/or support research and education, as well as doing “outreach”. But as government bodies, maybe we should try to go the extra mile and be role models when it comes to reducing climate and environmental impact?
 
When the Abisko Scientific Research Station was built, electricity was cheap, and all heating was done through electrical radiators. Today, that is not the best technology, climate-wise or money-wise. For some years now, a limited part of the station’s main building has been heated through geothermal heating. Right now, the National Property Board Sweden (Statens fastighetsverk) is planning for extending this to all of the main building during 2022. For the other building we are, house by house, replacing the direct electric heating with air source heat pumps.
 
The new heating regimes still need electricity, but much less so. And this summer we have put up solar panels, so that we at least during the summertime can produce part of our electricity needs. We have also purchased an electric car (Skoda Enyaq). This may seem like a bit of a gamble given the long cold winters in Abisko, but it will mainly be used by visiting researchers during the field season. And as most of the distances driven are quite short (10-20 km), an electric car should be ideal."
SITES enables multi-disciplinary and integrative research on terrestrial and aquatic ecosystems, including long-term effects of land use change, climate change, biodiversity loss. SITES enables multi-disciplinary and integrative research on terrestrial and aquatic ecosystems, including long-term effects of land use change, climate change, biodiversity loss.
The Swedish Infrastructure for Ecosystem Science (SITES) has been awarded continued funding for the grant period 2023-2027, under the Swedish Research Council’s (VR) call for research infrastructures of national interest.

SITES was launched in 2013 and now approaches the end of the second VR funding period. With the new funding, SITES can look forward to continuing operations during a third funding period where SITES will continue to promote high-quality research across Sweden linked to the research stations.

In the coming funding period, SITES will deepen the collaboration with other relevant research infrastructures and networks across Sweden, e.g. ICOS (Integrated Carbon Observation System) and ACTRIS (The Aerosol, Clouds and Trace Gases Research Infrastructure), and also engage internationally within the eLTER (European Long-Term Ecosystem Research) network.
 
“The continued funding is a recognition of the high quality and scientific impact of the support provided by our infrastructure”, says SITES Director Stefan Bertilsson, and adds that the new funding will both secure long-term monitoring programs within the station network and enable the infrastructure to develop in order to meet the future needs of researchers and other stakeholders. 

The current funding period started in 2018 and runs until the end of 2022. The funding details for the next period (2023-2027) and the terms of reference will be finalized later this year in dialog with VR.
Carbon dynamics and wetland restoration is among the topics focused on at Trollberget experimental area, part of Svartberget Research Station. Photo: Blaize Denfeld. Carbon dynamics and wetland restoration is among the topics focused on at Trollberget experimental area, part of Svartberget Research Station. Photo: Blaize Denfeld.
Research at SITES stations Skogaryd and Svartberget was recently highlighted in the science show Vetenskapens värld on Swedish television.

Several of SITES stations conduct research about forests and forestry, and related topics such as climate change. A recent television program on Swedish television included footage from Skogaryd and Svartberget, and researchers connected to SITES, including two of SITES previous Directors Anders Lindroth and Tomas Lundmark.

Watch the program online at SVT.se (In Swedish): Vetenskapens värld: Slaget om skogen. Svartberget is featured in the first episode and Skogaryd in episode 4.

Skogaryd was also included in another television program last week, where docent Åsa Kasimir explained about managed wetlands and their contribution to  greenhouse gas emissions: Uppdrag granskning: Klimatbomben (in Swedish). Svartberget is also active in this field, with ongoing research at Trollberget investigating wetland restoration and buffer management on the carbon dynamics and water quality.
Agroecology students at a field walk at Lönnstorp Research Station in late September. Photo: Marie-Claire Feller. Agroecology students at a field walk at Lönnstorp Research Station in late September. Photo: Marie-Claire Feller.
Finally! Students are back at SITES Lönnstorp. During September several different student activities took place.

The Agroecology and the Horticultural students took a field walk around the research station during two different occasions. The field walks were mainly focused on the SAFE (SITES Agroecological Field Experiment) infrastructure but the students were also shown and told about other experiments that are ongoing at the station (e.g. Strip-till establishment, Flower strips 2.0, and Tree seedling establishment).

Students attending the course Sustainable soil management in agroecosystems also had activities at SITES Lönnstorp. They, among other things, used different kinds of equipment (e.g. TDRs, lysimeters and penetrometers) to measure and assess different types of soil characteristics.

Lönnstorp Research Station also hosted students from Lund University, who took a field walk as well as set up and performed eddy covariance measurements at the station. Furthermore, Daniel Brainard, a professor in sustainable agriculture and ecological weed management at Michigan State University (USA), also paid the station a visit in September.

– We hope that more researchers, students, companies, organizations, and the public will visit us during the coming months, says Johannes Albertsson, SITES Station manager at Lönnstorp.

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