If you live in Catalonia, you may have been surprised how over the last few months a small plane flew over wooded areas, at low altitude and without following any apparently defined route. The most surprising thing, however, is not where or how I fly, but what its objective is: neither more nor less than launching laser beams on the tops of the holm oaks, pines and oaks, shrubs, scrub and other vegetation of the region’s forests. . Everything to know them in greater detail.
A revisiting of that old adage “don’t let the trees block you from seeing the forest”, only in a 21st century version, with plane and laser mapping included.
What does that plane look like there? Over the last few months, it is likely that more than one resident of Catalonia, especially those who live closest to wooded areas, have asked themselves that or a similar question. The story is told by El Periódico: for some time now a small aircraft has been flying over the region at low altitude, focusing above all on the groves.
His maneuvers, however, have little mystery, which (eye) is not spectacular. The person in charge of the flights is the Cartographic and Geological Institute of Catalonia (ICGC) and its objective is to collect data from the heights provided by the Center for Ecological Research and Forestry Applications (CREAF).
And how do you get the data? Here’s the most interesting. The technicians who traveled on board the plane are not dedicated to taking pictures or taking notes from a bird’s eye view. The tool they use is much more precise and useful so that scientists can, for example, get an idea of the health of the grove: LiDAR, which stands for Laser Imaging Detection and Ranging.
Its operation is relatively simple, at least on paper: a laser beam is thrown towards an object or surface so that it bounces and then calculates the time it takes to capture its reflection. Thanks to this process, technicians can determine the distance between the emitting source and its “target”.
What is it used for in Catalonia? To get to know its forests better. With the information, the technicians can map the groves, know the relief of the terrain, determine the height of the vegetation and study its condition. “Discovering whether or not there is undergrowth and verifying the heterogeneity or homogeneity of the vegetation is key to assessing the health of each forest,” Jordi Vayreda, from CREAF, acknowledges to El Periódico.
With these data on the table, aspects such as the risk of fire or knowing the vegetation in greater detail can be assessed. It is not your only tool, of course. For other analyses, such as the one focused on the effects of drought, Sentinel is used.
Is it the first time it is used? No. The LISAR has already been used on other occasions in Catalonia, such as in the flights carried out between 2008 and 2011 or from 2015 to 2016 to map the region. “The data allow discrete changes to be mapped at a very high resolution, covering large areas in a uniform and very precise way,” they explain from the ICGC, which clarifies that the shrub cover of Catalan forests is today “a very poorly determined variable “.
“This cover is often responsible for the rapid proliferation of fire and ignorance makes it difficult to carry out good forest management to fight large forest fires or to know the impacts of climate change on the decline of forests or the loss of biodiversity”, the organism abounds. Its technicians have the maps obtained with the LiDARCAT 1 and 2 and IFN4 projects.
Has it only been used in Catalonia? The answer is again no. As highlighted by the Polytechnic University of Madrid, technology, which started with scientific applications already in the 1960s, has played a very relevant role in mapping specific areas. Thanks to her we have discovered a Mayan heritage or expanded our knowledge of Teotihuacán.
Even NASA has turned to LiDAR, both to prepare for exploration of the lunar South Pole and to learn about the planet’s forests. That is the purpose, for example, of the GEDI mission, developed by the agency and the University of Maryland and which precisely uses technology to obtain high-resolution observations of the 3D structure of the Earth and map remote forest areas, an interesting fact for example. to draw up more effective strategies for CO2 capture.
Images: Kees Torn (Flickr) and ICGC
In Xataka: NASA has been launching lasers from the International Space Station for years. There is a good reason behind
