Low-cost drones fly to the rescue of the world's forests

February 22, 2019, CORDIS
Credit: Filipe Frazao, Shutterstock

Almost 1.6 billion people – more than a quarter of the global population – rely on forests for their livelihood. Of this number, it's said that around 60 million indigenous people are almost entirely dependent on forests to survive. Forests not only help these people to subsist, they also provide a number of essential services. They protect the soil, regulate water and support biodiversity. Equally important, they also store carbon, playing an important role in the fight against climate change.

Deforestation and forest degradation are responsible for about 17 % of emitting more CO2 than the world's entire transportation sector. Each year around 7 million hectares of forest are lost to deforestation. Initiatives such as REDD+ offer incentives to countries to reduce their emissions by keeping their forests standing. Countries receive payments based on the amount of carbon stored in their forests. However accurate measuring and monitoring of biomass (the quantity of living plant material) and hence carbon stock can be expensive and difficult to achieve. This is especially true for Brazil's vast forests where biomass mapping via is challenging due to cloud cover.

To address this challenge a research team comprising members from Brazil and six European countries launched the EU-funded project COREGAL in 2015. Using a technique called Global Navigation Satellite System-Reflectometry (GNSS-R) the team developed low-cost drones that map biomass as they fly over the forest. "If you can measure the biomass you can measure the carbon and get a number which has value for a country" says satellite and flight system expert Pedro Freire da Silva of project coordinator Deimos Engenharia in an article posted on 'Phys.org'.

How do the drones work?

The automated drones have a special receiver, called a combined Position-Reflectometry Galileo receiver, that's used to determine position and as a biomass sensor. The signals transmitted by the GNSS satellite are reflected on the forest ground and then received by the biomass sensor. These reflected signals are distorted and weakened as they pass through tree canopies, branches and leaves. "The more leaves you have, the more power (from GPS and Galileo) is lost," says da Silva. This means that the weaker the signal received by the drone is, the more biomass there is in the below. "If you combine this data with we get a more accurate map of biomass than either would (alone)," he adds.

Project partners conducted flight trials for their in Portugal as a stepping stone to improving biomass mapping in Brazil, which is home to a third of the world's rainforests. Now closed, COREGAL (Combined Positioning-Reflectometry Galileo Code Receiver for Forest Management) aimed to provide wide-scale and high-accuracy biomass mapping in worldwide regions with forests.

Explore further: Drones and satellite imaging to make forest protection pay

More information: COREGAL project website: www.coregalproject.com/

Related Stories

Drones and satellite imaging to make forest protection pay

December 17, 2018

Every year 7 million hectares of forest are cut down, chipping away at the 485 gigatonnes of carbon dioxide (CO2) stored in trees around the world, but low-cost drones and new satellite imaging could soon protect these carbon ...

GNSS technology for better biomass mapping

June 10, 2016

The EU-funded COREGAL project combines traditional positioning technology with reflected global navigation satellite system (GNSS) signals to let land management professionals see through thick tree canopies and better understand ...

Image: Biomass Earth Explorer satellite

February 13, 2019

Set to fly in 2022, ESA's Biomass Earth Explorer satellite with its 12-m diameter radar antenna will pierce through woodland canopies to perform a global survey of Earth's forests – and see how they change over the course ...

New approach to measuring carbon in forests

March 26, 2008

CSIRO is collaborating in a NASA-funded project, using a CSIRO-designed instrument, to help develop new methods of measuring forest carbon stores on a large scale.

Earth's northern biomass mapped and measured

June 27, 2013

The biomass of the northern hemisphere's forests has been mapped with greater precision than ever before thanks to satellites, improving our understanding of the carbon cycle and our prediction of Earth's future climate.

Recommended for you

Galactic center visualization delivers star power

March 21, 2019

Want to take a trip to the center of the Milky Way? Check out a new immersive, ultra-high-definition visualization. This 360-movie offers an unparalleled opportunity to look around the center of the galaxy, from the vantage ...

Physicists reveal why matter dominates universe

March 21, 2019

Physicists in the College of Arts and Sciences at Syracuse University have confirmed that matter and antimatter decay differently for elementary particles containing charmed quarks.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.