Over the past week and a half, we have been prepping for the winter break. We have handed in rough drafts that will be crucial to the completion of our project, such as the GIS Report and the Lab Report, which describes our processes and motivation. We also had our last individual client meeting at the Noord-Brabant Province House in s’Hertogenbosch where we updated our clients on our data findings.
At this point, we have not yet finished our GIS work to show the completed map with areas vulnerable to excess plant growth and a full comparison to previous years. However, we do have a sample map to show. The map on the top left shows the sample area. This photograph is an image we have stitched together using over 100 aerial photographs taken with the drone. Below, this image shows a rough classification of the ground coverage. This was made by comparing the visible colour index of each pixel in the photograph then estimating the vegetation coverage. Each pixel was about 2cm on the ground, but the GIS software could not easily process this amount of information, and because this amount of detail was not needed, we made each pixel equal to 15cm of area on the ground.
Along with the photograph using the visible colour, we also compared an image using infrared imagery. This image shows better displays differentiation between vegetation and the various classes of ground coverage. However, the resolution is much less than the aerial photographs using the drone. This image can be found at the bottom of this blog post.
The image to the right shows the locations where we have taken our samples, before the beginning of last week. The points in green are locations where we have taken samples this year. The points in red are areas taken from 2016. We chose our locations based on ground coverage. This means that different samples were taken on a different types of vegetation coverage.
Following the sample collection, we processed the samples in the lab to find the pH, Total Nitrogen, Total Organic Nitrogen, and Ammonia. These variables were chosen because Nitrogen is the driving force that causes the plants to grow faster than normal. Overall, the samples showed that the areas in sand were lower in Nitrogen and areas with more vegetation coverage contained high amounts of Nitrogen. We believe this to be true because the sandy soils are more porous and allow water to move the Nitrogen and other nutrients away easier. The samples also showed that the soil has a pH ranging from 3.5-5.0. This acidic soil is common in this area, and the plants have adapted here to thrive in these soils.
We will continue to work in the lab and return to the field to gather more information about the park. With this new information that we have processed, we have already begun to develop a management and monitoring plan to our clients!
Our week began on Monday when our group met with our project supervisor, Maurits, to discuss our progress. From here we then planned to return to the field with the drone, but then we received disastrous news. The drone had been used by another student group on a coastal setting, but as they were taking photographs, the weather quickly changed, and a light rain began. The group immediately manoeuvred the drone back home, but after only a few minutes the water had damaged the internal electronics of the drone, and control was lost. The drone then crashed into a sand dune and one propeller suffered a small chip. Although the chip was only the size of a large scratch, this would greatly offset the balance of the drone. This would make controlling the drone be near impossible, as well as waste battery power faster for stabilisation. Aerial photography will have to be postponed for about a week until a new propeller arrives.
On Tuesday, we met with our client, Hans van Dijk from Natuurmonumenten, on Avans campus. Our main goal of this meeting was to update our progress, as well as gain insight on what our management and monitoring plan would be. One idea was that a posted information sign near the entrance could describe the history of the park, and how recent pollution assists with vegetation taking over the sand. Most of the public is unaware of the negative changes within the park, and we believe that this could raise public awareness. If people are interested to learn more about the Loonse en Drunense Duinen Park (as well as other protected areas), there is a surplus of information found on the Natuurmonumenten website. https://www.natuurmonumenten.nl/
Later in the week, both teams met with our second client, Liesbet Dirven from RIVM. Our teams met with Liesbet at the RIVM headquarters, just outside of Utrecht city. Representatives from ANK (Atlas Natural Capital) also joined the meeting to discuss our lab and drone findings. ANK is a partner with RIVM that works to use the natural resources in a sustainable way. The meeting went well, with all parties voicing their questions and opinions about the project. We are now happy to say that we will create a vegetation succession map showing the rate of change in vegetation per year.
After our meeting, Liesbet was able to show us around the large property owned by RIVM. Much of the property is used for research and testing for various experiments. We were even able to view a lab that is used for cancer cell research. Due to security and the confidentiality of these experiments, we were not able to take any photos. However if you are interested in learning more about their work, you can check out their website to read a variety of articles from food safety to antibiotic resistance. http://www.rivm.nl/en
This past week we were finally able to process many of the photos taken with the drone. The photo shown here is a typical photo taken by the drone. The drone is a DJI Phantom 3 Standard, which has a camera attached to the bottom. Before flight, the drone is calibrated by two people in order to keep it balanced in the air. The calibration also allows it to withstand stronger winds above the tree line. We fly our drone at a set height of 80 metres to cover a larger area for each photo that the camera captures. The drone has a sensor within it to calculate its height, which then adjusts as it flies over a changing environment. This is important because the photographs that the drone takes needs to fit together at the correct proportions. In total, we aim to cover a total sampling area of about 340 hectares for our group. This area will be put together with the other team working on the project to create a larger map of the desert. You can also check on the other teams work at http://saving-the-looney-dunes.mozello.com
While processing the GIS photos, we also found time to return to the lab to test for Total Nitrogen in our water samples. We did this by using the Kjeldahl method in the Avans labs. We first started by “digesting” all organic matter in a strong acid at high temperatures. After this, we moved our samples into a machine that distils our samples by adding a base to the solution, then boiling it to collect the nitrogen rich condensation. Finally, we end our process by titrating our samples to calculate the Total Nitrogen. This is a process in which an acid is added until a certain pH is reached. The amount of acid used to reach the desired pH determines the Total Nitrogen. After viewing our results, we discovered that the data was incomprehensible! Emese, our lab specialist, and Phill concluded that the concentrations of Nitrogen in the water were so low that the Kjeldahl method could not properly measure the samples. However, we hypothesised that the soil samples would contain more Nitrogen than the water samples.
We plan to continue using the Kjeldahl method for the soil samples, but we will switch to using Ion Chromatography for a more precise reading on the water samples for next week.
Last week we made our last excursion to the Loonse en Drunense Duinen for the time being, but we will return in a few weeks. Our goal was to put greater focus into planning for our future days working in the lab at Avans and to prepare how to present the data that we find.
At the start of the week, we arrived to the park on an unusually warmer day. We have taken all of our samples from more local points, so we were forced to make a longer journey towards the centre of the park. On this sunny day it began to feel like an actual desert, especially with our thick layers of clothing. The warmer weather also brought in many more visitors too. Many people were curious about our equipment and the drone and asked questions. We are thrilled to see so many people who are interested in work done in the park.
Later in the week we made a quick trip to the lab at Avans University. There we tested for Total Nitrogen in the surface and ground water. We did this by first preparing the sample and adding indicators to the water. After heating the sample for about an hour, we then read the results using the Hach Lange Spectrophotometer. This is a device that sends a specific wavelength through a water sample, and reads the changes of the wavelength on the receiving end. These changes can then be translated into the amount of what you are testing for.
At the end of the week, Lars had to leave for a planned minor surgery. We all hope that he will have a smooth painless recovery!
Windy. Rainy. Frosty. As the months change, we’ve noticed a shift in weather this week compared to the previous. However, this didn’t stop the locals and students from visiting the park and breaking routine. When we arrived for our first day this week, we found ourselves walking past different school groups teaching their students about the park and the values of nature.
After we walked for a few minutes, we located our first sampling location and began drilling. While Phill and Lars were drilling, Magda and Emese began to set up the drone for aerial photographs. However, shortly after take-off, it was apparent that the drone would not be able to fly in the high winds that day. The drone returned just in time, because as it landed the rain began. If the drone is exposed to too much water, it could experience electrical problems.
On our second visit the park this week, the wind and rain subsided enough for us to make our first launch with the drone! The drone works for about 20 minutes with one battery to cover an area roughly 30 hectares. Before the battery is completely drained, we return the drone home to replace it with a new battery. While landing it, a curious dog came running over to see what the strange machine was. Dogs will often attack a drone, but thankfully this pupper only remained as a spectator.
Whenever someone is operating the drone, there is another counterpart drilling for soil and groundwater being done. If we are lucky, the water table is less than two metres deep. However, in some cases, we have to drill over three metres until we reach groundwater. Lars is our tallest member of the team, but even he needs help from someone else sometimes.
After we collect our samples, we store them in refrigerators in Avans University to preserve them until testing. While returning returned one day, we met with another student named Yoko. Yoko is working on another project independently, but used some of our samples in her own research. Her results benefit us too because her findings save us time in the lab! We hope to process some of our results soon and will share with you what we discover!
This past week the team made our first visit to the desert. Here we met our clients and even got a tour of the dunes! Over the tour we saw a lot of action happening around the park from bikers on trails, to families exploring the dunes, to horseback riders wondering the desert.
After the tour we quickly began to collect our soil and groundwater samples. We drilled a borehole over two metres until we reached the water table. Along the way we laid out the soil to see the changes over depth. The uppermost soil was a darker brown, indicating that it contained a lot of organic matter to sustain plant growth. This bad news, as vegetation prevents the natural drifting of the sands and threatens different species, such as the rare European Nightjar. Fortunately, after drilling a few more centimetres we reached the healthy layer of sand.
Half way through our sampling we were ambushed by friendly sheep grazing on the native heather. The sheep were introduced years ago by Natuurmonumenten to help control the spreading of the vegetation. With less vegetation the native species can thrive in their sandy home.
After our visitors continued through the park, we began our next task to collect the groundwater. To do this we inserted a hollow, sieved pole into the borehole we made. When the pole reached the water table, the water entered the centre of the pole but the sand could not fit through the sieves. We then inserted a pump that drew out the water for collection.
As the sun began to set, we made our way back home and stored our samples in our lab back at Avans University. Next week we will begin our tests to see the health of the samples and will also be collecting more from different locations throughout the park. I am excited to return next week and cannot wait to explore more areas of the desert!
This is a blog about the group of Emese Orosz, Magdalena Gorska, Lars van Kleef & Phillip Worster. We have taken on the project to work with Natuurmonumenten, Province Noord-Brabant, and RIVM. Our mission is to investigate the area of Loonse en Drunense Duinen, and to see why vegetation is taking over the protected sandy desert and how to manage it for the future.
During our first days, we met with the representatives from each of our clients. We discussed the requests and needs for this project. Over the next week, our group divided the work into four roles for each member. Emese takes the role of our Laboratory Specialist and the needs around it. Lars will take the role of our GIS specialist and will supervise the map making process. Phill will take the role of the Secretary and will focus on taking minutes and supervises promotional activities. Last but not least, Magda will take the role of out trusted leader and will focus on the schedules, leading meetings, and will act as the contact between our group and our clients. We have also made our Plan of Approach towards this project, as well as other necessary form.
We have only just begun our project but we plan to visit our site with a photography drone next week. Check out next weeks post for more information!