Trees outside forests

Research combining Machine Learning, Remote Sensing and Geography to discover unprecedented knowledge at the level of individual trees



Terrestrial ecosystems are defined in large part by their woody plants. Grasslands, shrublands, savannahs, woodlands and forests represent a series of gradations in tree and shrub density, from ecosystems with low-density, low-stature woody plants to those with taller trees and overlapping canopies. Accurate information on the woody-vegetation structure of ecosystems is, therefore, fundamental to our understanding of global-scale ecology, biogeography and the biogeochemical cycles of carbon, water and other nutrients. 

The spatial resolution of most satellite data is relatively coarse, which has forced researchers in the field of Earth observation to focus on measuring bulk properties, such as the proportion of a landscape covered by tree canopies when viewed from above (a measurement known as canopy cover).

During the past two decades, a variety of commercial satellites have begun to collect data at a higher spatial resolution, capable of capturing ground objects measuring one square metre or less. This resolution improvement places the field of terrestrial remote sensing on the threshold of a fundamental leap forward: from focusing on aggregate landscape-scale measurements to having the potential to map the location and canopy size of every tree over large regional or global scales. This revolution in observational capabilities will undoubtedly drive fundamental changes in how we think about, monitor, model and manage global terrestrial ecosystems.

(Hanan & Anchang, 2020: https://www.nature.com/articles/d41586-020-02830-3)

Trees outside forests in global drylands (TOFDRY)

ERC starting grant

TOFDRY aims to quantify the worlds non-forest trees by using PlanetScope satellite imagery and a deep learning technique which is able to identify objects within imagery at unprecedented accuracy.


Country-scale assessment of individual trees in Africa

DFF Sapere Aude Danish Research Leader Grant in collaboration with NASA

Mapping individual trees in Africa

Image by David Clode

Tree biomass in European Forests

In collaboration with Kayrros and LSCE

This project aims at assessing biomass of individual trees in European forests.

Image by Geran de Klerk

The Carbon Sink of Southern China

in collaboration with the Institute of Subtropical Agriculture, Changsha, China

We investigate the impact of afforestation projects on the karst landscapes of Southern China.


Global carbon stock and vegetation monitoring

Together with INRAE and LSCE

Coarse scale monitoring of global carbon sinks and vegetation dynamics, and what biotic and abiotic factors drive them.

Image by Sebastian Unrau