How are our French forests doing? They cover a third of our territory. A huge area, the fourth in Europe, that experts from the program of the National Institute of Geographic and Forest Information are mapping using high-density Lidar. Europe 1, partner of Le Pèlerin magazine, accompanied them.
Experts from the National Institute for Geographic and Forest Information map the 182,000 km2 covered by metropolitan and overseas forests (excluding Guyana). The goal ? Find out if they are doing well and understand how to better protect them against the vagaries of the weather. For the past year, three airliners have crisscrossed France, equipped with their high-density Lidar (Light Detection And Ranging). A technology that has replaced aerial photography. This laser makes it possible to identify everything that is on the ground in a very fine way.
Data processed by the team of geographic information technicians, of which Guillaume is a member. “We have automatic classifications depending on the angles, depending on what the laser hits. It knows how to recognize what is on the ground, even forest species”, he explains at the microphone of Europe 1.
This method gives a panoramic view of the state of our forests, complementary to the inventories carried out on the ground, according to Magali Jover, forest specialist at the National Institute of Geographic and Forest Information.
A decline in annual organic production
“One might think that the forest is doing well since the inventory tells us that the forest area continues to increase each year. It covers 31% of the national territory. However, this is not the case. annual biological production and increasing mortality”, she laments on Europe 1.
For now, HD Lidar has covered 20% of the territory. Total cost of the operation over five years: 60 million euros with, at the end of the day, crucial data that will be used in particular by researchers and the development of future public policies.