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In late autumn, work at SITES station Grimsö mainly comprises of digitalization and compilation of data from the earlier peak season, and lab work to specify ticks sampled from voles etc. However, outdoor activities still run in autumn, one of which is the hazel grouse survey.

A hazel grouse male in its typical habitat, dense spruce forest mixed with deciduous trees, preferably alder (Alnus spp.) Photo: Cecilia Di Bernardi A hazel grouse male in its typical habitat, dense spruce forest mixed with deciduous trees, preferably alder (Alnus spp.) Photo: Cecilia Di Bernardi

The hazel grouse (Bonasa bonasia) survey at SITES Grimsö started in 1987 as part of a conventional research project. This quite anonymous species is strongly connected to specific habitat features and the data obtained during the initial project showed to be interesting, and unique for Sweden. Thus, the annual counts continued as a monitoring program after the initial project ended. The hazel grouse is included in some of the national bird monitoring programs, but the large-scale and long-term survey designed only for hazel grouse at Grimsö, is rare also at the international level.

The survey is conducted as territorial mapping in part of the research area, and the method includes the use of a whistle imitating the territorial song of a male hazel grouse. A systematic and dense network of whistle points are applied throughout the study area, so all territory holders, either just the male or a male and female together, are found. In the last Decades, hazel grouse have shown strong declines in southern Sweden, which is also mirrored in our survey. This highlights the importance of long-term and detailed data which improves the understanding of causes and effects behind population trends.

As part of the work to prevent and monitor forest damage, the government has invested money in a National Center for Forest Damage. The Center is a collaboration program, where SLU’s Skogsskadecentrum (Forest Damage Center) has participated in several projects in collaboration with other actors.

Ground trap used to catch Hylastes. Photo: Kristina Wallertz Ground trap used to catch Hylastes. Photo: Kristina Wallertz

SLU’s Unit for Field-based Forest Research received a small sum to start up a number of pilot experiments, one of which is at SITES Asa Research Station, focused on developing a method for catching black bark beetles (Hylastes) in ground traps. 

Hylastes can cause severe damage to newly planted seedlings by eating the bark of the roots, sometimes severe enough to kill the seedlings. The damage seems to have increased in recent years in southern Sweden. At Asa, experiments investigating the damage of Hylastes on seedlings have been conducted. However, since Hylastes mainly feed on roots in the ground, it is necessary to harvest the seedlings in order to investigate the damage, which is a very labor-intensive and costly effort. Therefore, the study was designed to catch the insects in ground traps. A standardized method monitoring the presence of Hylastes with ground traps increases knowledge about occurrence, species variation, etc.

Here, the experimental parks are an excellent resource for broadening the monitoring and contributing with long-time series in a wider geographic area. 
However before investigating on such a larger scale, the methodology needs to be tested and staff trained.

Pilot project at Asa

A Hylastes spotted on a tree branch during the experiment. Photo: Kristina Wallertz A Hylastes spotted on a tree branch during the experiment. Photo: Kristina Wallertz

In the present pilot project, insects were collected from eight different clear-cuts near Asa experimental park. Ten ground traps per location were placed and emptied at regular intervals during June-August 2021. All insects were stored for later species identification.

Åke Lindelöw, field entomologist with long-term experience and well-known knowledge of Hylastes, helped to train the team to distinguish between the different species found in the traps. During the season, 3791 Hylastes were collected from the traps of which about 7% were Hylastes brunneus and 93 % Hylastes cunicularius.

“We have learned a lot from the study, both in terms of species determination and methodology. With small changes, we can make collection both easier and more efficient. We also think we are quite good at distinguishing between the two species of Hylastes and excluding other species from the catches. Now we only hope for a positive message for future financing which makes it possible to continue but also expand this monitoring of Hylastes.” - Kristina Wallertz

Sydvatten at Lake Bolmen, has joined with VA SYD Källby Water Workshop and NSVA RecoLab, on a collaborative Vinnova funded test bed to develop online drinking water quality monitoring. The Testbed project was presented during the National Drinking Water conference, 26 of October, in Malmö.

Lake Bolmen, Skåne's most important drinking water source. Lake Bolmen, Skåne's most important drinking water source.

Sydvatten research station, situated at Lake Bolmen, in association with VA SYD Källby Water Workshop, in Lund, and NSVA RecoLab in Helsingborg, have initiated a Vinnova funded test bed. The collaboration aids in developing methods which will enable online quality monitoring and hence, contribute to safer drinking water management. This will provide operating personnel more time to react  in the event of incidents, such as leakage or contamination, thus reducing the risk to the public. 

Although the organizations involved are all linked within the water industry, they individually represent different phases of drinking water management through the consumption of this most precious resource. The Research Station Bolmen mainly focuses on the raw product, which in this case is the surface water of Lake Bolmen, one of the major drinking water sources for South Sweden. Källby Water Workshop focuses on both the quality and delivery of drinking water. RecoLab, an urban wastewater testbed with access to sorted wastewater streams, allows for testing on different types of wastewaters, as well as testing water at different steps during the treatment process.

The Testbed project was presented during the National Drinking Water conference, 26 of October, in Malmö. Guests were invited to make a digital visit to the test beds here. The presentation was hosted by Markus Fröjd, a research leader at Sweden Water Research and Esmeralda Frihammar, development engineer at VA SYD.
 
Together, these collaborating test beds, offer prospective developers a collective experience and expertise through the entire water cycle – all the way from raw water, through drinking water, to the recycled wastewater 

More about the project can be found here.  
 

An overview diagram of the collaborative funded test bed to develop online drinking water quality monitoring.
An overview diagram of the collaborative funded test bed to develop online drinking water quality monitoring.

SITES AquaNet plans for a coordinated mesocosm experiment on the effect of run-off variability in five lakes next summer. A call for researchers and students to participate will open soon.

SITES AquaNet Mesocosm enclosure at Skogaryd Research Catchment (Photo: Leif Klemedtsson) SITES AquaNet Mesocosm enclosure at Skogaryd Research Catchment (Photo: Leif Klemedtsson)

SITES AquaNet will soon launch a call within the EU project AQUACOSM-plus to invite research groups, individual researchers and students to apply to join a coordinated mesocosm experiment at all five SITES stations participating in the AquaNet Program. The experiment aims to involve many national and international researcher and students in the planning, implementation and analysis of the experiment.
 
The scientific focus of the experiment will be to investigate how differences in run-off variability during summer precipitation events impact the transport of resources, such as organic matter and nutrients, into lakes, and thus affect the composition and function of lake communities. This is important to study as nutrient pulse variability is expected to increase in the future as precipitation events will become more extreme, due to stronger and flashier rainfall, floods, and extended periods with droughts. To address such questions, spatially coordinated experiments that look at responses to standardized manipulations with standardized equipment and methods are crucial tools. SITES AquaNet is well suited in this regard since the program is designed to implement standardized experiments across lakes. Moreover, the mesocosms at each station allow for temporal high-frequency measurements of phytoplankton and cyanobacterial biomass and ecosystem metabolism, such as primary production and respiration.
 
You are welcome to apply to join us in this exciting mission of running a large, coordinated experiment! AQUACOSM-plus provides Transnational Access (TA) free of charge to approved users to at least one of the partner facilities, including costs for travel, housing and meal expenses. Applications will soon be accepted for the 2022 SITES AquaNet-AQUACOSM-plus project.

More information about the experimental set-up and the application.

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.

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